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Sample records for general relativistic equilibrium

  1. General Relativistic Equilibrium Models of Magnetized Neutron Stars

    CERN Document Server

    Pili, A G; Del Zanna, L

    2013-01-01

    Magnetic fields play a crucial role in many astrophysical scenarios and, in particular, are of paramount importance in the emission mechanism and evolution of Neutron Stars (NSs). To understand the role of the magnetic field in compact objects it is important to obtain, as a first step, accurate equilibrium models for magnetized NSs. Using the conformally flat approximation we solve the Einstein's equations together with the GRMHD equations in the case of a static axisymmetryc NS taking into account different types of magnetic configuration. This allows us to investigate the effect of the magnetic field on global properties of NSs such as their deformation.

  2. Cosmology and stellar equilibrium using Newtonian hydrodynamics with general relativistic pressure

    CERN Document Server

    Baqui, P O; Piattella, O F

    2015-01-01

    We revisit the analysis made by Hwang and Noh [JCAP 1310 (2013)] aiming the construction of a Newtonian set of equations incorporating pressure effects typical of General Relativity theory. We perform in an explicit way the deduction of the Hwang-Noh equations, comparing it with similar computations found in the literature. Later, we investigate stellar equilibrium and cosmology, at background and perturbative levels, using the new set of equations. It is shown that, in this context, the predictions for the background evolution of the universe are deeply changed with respect to the full relativistic theory: the acceleration of the universe is achieved with positive pressure. The properties of neutron stars are reproduced qualitatively, but the upper mass is at least one order of magnitude higher than that obtained in General Relativity. However, the perturbed cosmological equations at small scales reproduce those found in the relativistic context. We argue that this last result may open new possibilities for ...

  3. GENERAL EQUILIBRIUM

    Directory of Open Access Journals (Sweden)

    Monique Florenzano

    2008-09-01

    Full Text Available General equilibrium is a central concept of economic theory. Unlike partial equilibrium analysis which study the equilibrium of a particular market under the clause “ceteris paribus” that revenues and prices on the other markets stay approximately unaffected, the ambition of a general equilibrium model is to analyze the simultaneous equilibrium in all markets of a competitive economy. Definition of the abstract model, some of its basic results and insights are presented. The important issues of uniqueness and local uniqueness of equilibrium are sketched; they are the condition for a predictive power of the theory and its ability to allow for statics comparisons. Finally, we review the main extensions of the general equilibrium model. Besides the natural extensions to infinitely many commodities and to a continuum of agents, some examples show how economic theory can accommodate the main ideas in order to study some contexts which were not thought of by the initial model

  4. BOOK REVIEW: Relativistic Figures of Equilibrium

    Science.gov (United States)

    Mars, M.

    2009-08-01

    Compact fluid bodies in equilibrium under its own gravitational field are abundant in the Universe and a proper treatment of them can only be carried out using the full theory of General Relativity. The problem is of enormous complexity as it involves two very different regimes, namely the interior and the exterior of the fluid, coupled through the surface of the body. This problem is very challenging both from a purely theoretical point of view, as well as regarding the obtaining of realistic models and the description of their physical properties. It is therefore an excellent piece of news that the book 'Relativistic Figures of Equilibrium' by R Meinel, M Ansorg, A Kleinwächter, G Neugebauer and D Petroff has been recently published. This book approaches the topic in depth and its contents will be of interest to a wide range of scientists working on gravitation, including theoreticians in general relativity, mathematical physicists, astrophysicists and numerical relativists. This is an advanced book that intends to present some of the present-day results on this topic. The most basic results are presented rather succinctly, and without going into the details, of their derivations. Although primarily not intended to serve as a textbook, the presentation is nevertheless self-contained and can therefore be of interest both for experts on the field as well as for anybody wishing to learn more about rotating self-gravitating compact bodies in equilibrium. It should be remarked, however, that this book makes a rather strong selection of topics and concentrates fundamentally on presenting the main results obtained by the authors during their research in this field. The book starts with a chapter where the fundamental aspects of rotating fluids in equilibrium, including its thermodynamic properties, are summarized. Of particular interest are the so-called mass-shedding limit, which is the limit where the body is rotating so fast that it is on the verge of starting

  5. Relativistic perfect fluids in local thermal equilibrium

    CERN Document Server

    Coll, Bartolomé; Sáez, Juan Antonio

    2016-01-01

    The inverse problem for conservative perfect fluid energy tensors provides a striking result. Namely that, in spite of its name, its historic origin or its usual conceptualization, the notion of {\\em local thermal equilibrium} for a perfect fluid is a {\\em purely hydrodynamic}, not thermodynamic, notion. This means that it may be thought, defined and detected using exclusively hydrodynamic quantities, without reference to temperature or any other thermodynamic concept, either of equilibrium or irreversible: a relativistic perfect fluid evolves in local thermal equilibrium if, and only if, its hydrodynamic variables evolve keeping a certain relation among them. This relation fixes, but only fixes, a precise fraction of the thermodynamics of the fluid, namely that relating the speed of its sound waves to the hydrodynamic variables. All thermodynamic schemes (sets of thermodynamic variables and their mutual relations) compatible with such a relation on the sole hydrodynamic variables are obtained. This hydrodyna...

  6. Relativistic electron ring equilibrium with angular momentum spread

    Energy Technology Data Exchange (ETDEWEB)

    Croitoru, M.; Grecu, D. (Institutul de Fizica si Inginerie Nucleara, Bucharest (Romania))

    1980-01-01

    The equilibrium properties of a relativistic electron ring are determined by solving in a consistent way the Vlasov-Maxwell equations for a distribution function with an angular momentum spread. In the thin ring approximation there have been deduced general formulae for the electron density and the current density. A general theorem concerning the sharp form in space of the electron density is also obtained for the case of a microcanonical distribution function both in energy and angular momentum.

  7. Cosmological particle production and generalized thermodynamic equilibrium

    CERN Document Server

    Zimdahl, W

    1998-01-01

    With the help of a conformal, timelike Killing-vector we define generalized equilibrium states for cosmological fluids with particle production. For massless particles the generalized equilibrium conditions require the production rate to vanish and the well known ``global'' equilibrium of standard relativistic thermodynamics is recovered as a limiting case. The equivalence between the creation rate for particles with nonzero mass and an effective viscous fluid pressure follows as a consequence of the generalized equilibrium properties. The implications of this equivalence for the cosmological dynamics are discussed, including the possibility of a power-law inflationary behaviour. For a simple gas a microscopic derivation for such kind of equilibrium is given on the basis of relativistic kinetic theory.

  8. Newtonian view of general relativistic stars

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, A.M. [Instituto Federal do Espirito Santo (IFES), Grupo de Ciencias Ambientais e Recursos Naturais, Guarapari (Brazil); Velten, H.E.S.; Fabris, J.C. [Universidade Federal do Espirito Santo (UFES), Departamento de Fisica, Vitoria (Brazil); Salako, I.G. [Institut de Mathematiques et de Sciences Physiques (IMSP), Porto-Novo (Benin)

    2014-11-15

    Although general relativistic cosmological solutions, even in the presence of pressure, can be mimicked by using neo-Newtonian hydrodynamics, it is not clear whether there exists the same Newtonian correspondence for spherical static configurations. General relativity solutions for stars are known as the Tolman-Oppenheimer-Volkoff (TOV) equations. On the other hand, the Newtonian description does not take into account the total pressure effects and therefore cannot be used in strong field regimes. We discuss how to incorporate pressure in the stellar equilibrium equations within the neo-Newtonian framework. We compare the Newtonian, neo-Newtonian, and the full relativistic theory by solving the equilibrium equations for both three approaches and calculating the mass-radius diagrams for some simple neutron stars' equations of state. (orig.)

  9. General Search Market Equilibrium

    OpenAIRE

    Albrecht, James W.; Axell, Bo

    1982-01-01

    In this paper we extend models of “search market equilibrium” to incorporate general equilibrium considerations. The model we treat is one with a single product market and a single labor market. Imperfectly informed individuals follow optimal strategies in searching for a suitably low price and high wage. For any distribution of price and wage offers across firms these optimal strategies generate product demand and labor supply schedules. Firms then choose prices and wages to maximize expecte...

  10. Quantum relativistic fluid at global thermodynamic equilibrium in curved spacetime

    CERN Document Server

    Becattini, F

    2015-01-01

    We present a new approach to the problem of the thermodynamical equilibrium of a quantum relativistic fluid in a curved spacetime in the limit of small curvature. We calculate the mean value of local operators by expanding the four-temperature Killing vector field in Riemann normal coordinates about the same spacetime point and we derive corrections with respect to the flat spacetime expressions. Thereby, we clarify the origin of the terms proportional to Riemann and Ricci tensors introduced in general hydrodynamic expansion of the stress-energy tensor.

  11. Relativistic non-equilibrium thermodynamics revisited

    CERN Document Server

    García-Colin, L S

    2006-01-01

    Relativistic irreversible thermodynamics is reformulated following the conventional approach proposed by Meixner in the non-relativistic case. Clear separation between mechanical and non-mechanical energy fluxes is made. The resulting equations for the entropy production and the local internal energy have the same structure as the non-relativistic ones. Assuming linear constitutive laws, it is shown that consistency is obtained both with the laws of thermodynamics and causality.

  12. General relativistic neutron stars with twisted magnetosphere

    CERN Document Server

    Pili, A G; Del Zanna, L

    2014-01-01

    Soft Gamma-Ray Repeaters and Anomalous X-Ray Pulsars are extreme manifestations of the most magnetized neutron stars: magnetars. The phenomenology of their emission and spectral properties strongly support the idea that the magnetospheres of these astrophysical objects are tightly twisted in the vicinity of the star. Previous studies on equilibrium configurations have so far focused on either the internal or the external magnetic field configuration, without considering a real coupling between the two fields. Here we investigate numerical equilibrium models of magnetized neutron stars endowed with a confined twisted magnetosphere, solving the general relativistic Grad-Shafranov equation both in the interior and in the exterior of the compact object. A comprehensive study of the parameters space is provided to investigate the effects of different current distributions on the overall magnetic field structure.

  13. General equilibrium without utility functions

    DEFF Research Database (Denmark)

    Balasko, Yves; Tvede, Mich

    2010-01-01

    How far can we go in weakening the assumptions of the general equilibrium model? Existence of equilibrium, structural stability and finiteness of equilibria of regular economies, genericity of regular economies and an index formula for the equilibria of regular economies have been known not to re......How far can we go in weakening the assumptions of the general equilibrium model? Existence of equilibrium, structural stability and finiteness of equilibria of regular economies, genericity of regular economies and an index formula for the equilibria of regular economies have been known...... and the diffeomorphism of the equilibrium manifold with a Euclidean space; (2) the diffeomorphism of the set of no-trade equilibria with a Euclidean space; (3) the openness and genericity of the set of regular equilibria as a subset of the equilibrium manifold; (4) for small trade vectors, the uniqueness, regularity...

  14. General relativity and relativistic astrophysics

    CERN Document Server

    Mukhopadhyay, Banibrata

    2016-01-01

    Einstein established the theory of general relativity and the corresponding field equation in 1915 and its vacuum solutions were obtained by Schwarzschild and Kerr for, respectively, static and rotating black holes, in 1916 and 1963, respectively. They are, however, still playing an indispensable role, even after 100 years of their original discovery, to explain high energy astrophysical phenomena. Application of the solutions of Einstein's equation to resolve astrophysical phenomena has formed an important branch, namely relativistic astrophysics. I devote this article to enlightening some of the current astrophysical problems based on general relativity. However, there seem to be some issues with regard to explaining certain astrophysical phenomena based on Einstein's theory alone. I show that Einstein's theory and its modified form, both are necessary to explain modern astrophysical processes, in particular, those related to compact objects.

  15. On Generalized Vector Equilibrium Problems

    Institute of Scientific and Technical Information of China (English)

    An-hua Wan; Jun-yi Fu; Wei-hua Mao

    2006-01-01

    A new generalized vector equilibrium problem involving set-valued mappings and the proper quasi-concavity of set-valued mappings in topological vector spaces are introduced; its existence theorems and the convexity of the solution sets are established.

  16. On general relativistic uniformly rotating white dwarfs

    CERN Document Server

    Boshkayev, Kuantay; Ruffini, Remo; Siutsou, Ivan

    2012-01-01

    Uniformly rotating white dwarfs (RWDs) are analyzed within the framework of general relativity. The Hartle's formalism is applied to construct self-consistently the internal and external solutions to the Einstein equations. The relativistic Feynman-Metropolis-Teller EoS that generalizes the Salpeter's one taking fully into account the finite size of nuclei, the Coulomb interactions as well as electroweak equilibrium in a self-consistent relativistic fashion is used to describe the WD matter. The mass, radius, angular momentum, eccentricity and quadrupole moment of RWDs are calculated as a function of the central density and rotation angular velocity. We construct the region of stability of RWDs taking into account the mass-shedding limit, inverse beta-decay instability, and the boundary established by the turning points of constant angular momentum sequences that separates stable from secularly unstable configurations. We found the minimum rotation periods 0.3, 0.5, 0.7 and 2.2 seconds and maximum masses 1.50...

  17. Equilibrium and non-equilibrium properties of a relativistic gas at the transition temperature

    Science.gov (United States)

    Chacón-Acosta, Guillermo

    2016-11-01

    The Jüttner distribution function for equilibrium relativistic fluids has two well-known limits, the non-relativistic limit at low temperatures and ultra-relativistic limit for high temperatures. Recently, the description of this transition in velocity space in the system, from a gaussian to a bimodal distribution was made by Mendoza et al. Physically, it is a transition between a regime where the relativistic energy is dominated by kinetic to another where the rest energy dominates. It has been found that the critical temperature at which the relativistic corrections becomes relevant, depends just on the dimension of the system, this allowed a description in terms of the theory of critical points (Montakhab et al.). In this contribution a review of the thermodynamic quantities that are only dependent on the ratio between temperature and critical temperature, and the dimension is made. We will also analyze the effects of critical temperature on dissipative processes in simple special relativistic fluids. Particularly, purely relativistic terms that are usually proportional to the number density gradient are studied. The transport coefficients can be written in terms of the transition temperature, this will allow us to identify the lower order relativistic effects just in terms of the dimension of the system.

  18. General relativistic Boltzmann equation, I: Covariant treatment

    NARCIS (Netherlands)

    Debbasch, F.; van Leeuwen, W.A.

    2009-01-01

    This series of two articles aims at dissipating the rather dense haze existing in the present literature around the General Relativistic Boltzmann equation. In this first article, the general relativistic one-particle distribution function in phase space is defined as an average of delta functions.

  19. General relativistic corrections and non-Gaussianity

    CERN Document Server

    Villa, Eleonora; Matarrese, Sabino

    2014-01-01

    General relativistic cosmology cannot be reduced to linear relativistic perturbations superposed on an isotropic and homogeneous (Friedmann-Robertson-Walker) background, even though such a simple scheme has been successfully applied to analyse a large variety of phenomena (such as Cosmic Microwave Background primary anisotropies, matter clustering on large scales, weak gravitational lensing, etc.). The general idea of going beyond this simple paradigm is what characterises most of the efforts made in recent years: the study of second and higher-order cosmological perturbations including all general relativistic contributions -- also in connection with primordial non-Gaussianities -- the idea of defining large-scale structure observables directly from a general relativistic perspective, the various attempts to go beyond the Newtonian approximation in the study of non-linear gravitational dynamics, by using e.g., Post-Newtonian treatments, are all examples of this general trend. Here we summarise some of these ...

  20. Relativistic Hydrodynamics and Non-Equilibrium Steady States

    CERN Document Server

    Spillane, Michael

    2015-01-01

    We review recent interest in the relativistic Riemann problem as a method for generating a non-equilibrium steady state. In the version of the problem under con- sideration, the initial conditions consist of a planar interface between two halves of a system held at different temperatures in a hydrodynamic regime. The new double shock solutions are in contrast with older solutions that involve one shock and one rarefaction wave. We use numerical simulations to show that the older solutions are preferred. Briefly we discuss the effects of a conserved charge. Finally, we discuss deforming the relativistic equations with a nonlinear term and how that deformation affects the temperature and velocity in the region connecting the asymptotic fluids.

  1. General equilibrium of an ecosystem.

    Science.gov (United States)

    Tschirhart, J

    2000-03-07

    Ecosystems and economies are inextricably linked: ecosystem models and economic models are not linked. Consequently, using either type of model to design policies for preserving ecosystems or improving economic performance omits important information. Improved policies would follow from a model that links the systems and accounts for the mutual feedbacks by recognizing how key ecosystem variables influence key economic variables, and vice versa. Because general equilibrium economic models already are widely used for policy making, the approach used here is to develop a general equilibrium ecosystem model which captures salient biological functions and which can be integrated with extant economic models. In the ecosystem model, each organism is assumed to be a net energy maximizer that must exert energy to capture biomass from other organisms. The exerted energies are the "prices" that are paid to biomass, and each organism takes the prices as signals over which it has no control. The maximization problem yields the organism's demand for and supply of biomass to other organisms as functions of the prices. The demands and supplies for each biomass are aggregated over all organisms in each species which establishes biomass markets wherein biomass prices are determined. A short-run equilibrium is established when all organisms are maximizing and demand equals supply in every biomass market. If a species exhibits positive (negative) net energy in equilibrium, its population increases (decreases) and a new equilibrium follows. The demand and supply forces in the biomass markets drive each species toward zero stored energy and a long-run equilibrium. Population adjustments are not based on typical Lotka-Volterra differential equations in which one entire population adjusts to another entire population thereby masking organism behavior; instead, individual organism behavior is central to population adjustments. Numerical simulations use a marine food web in Alaska to

  2. Local thermodynamical equilibrium and the β frame for a quantum relativistic fluid

    OpenAIRE

    Becattini, Francesco; Bucciantini, Leda; Grossi, Eduardo; Tinti, Leonardo

    2015-01-01

    We discuss the concept of local thermodynamical equilibrium in relativistic hydrodynamics in flat spacetime in a quantum statistical framework without an underlying kinetic description, suitable for strongly interacting fluids. We show that the appropriate definition of local equilibrium naturally leads to the introduction of a relativistic hydrodynamical frame in which the four-velocity vector is the one of a relativistic thermometer at equilibrium with the fluid, parallel to the inverse tem...

  3. Risk premia in general equilibrium

    DEFF Research Database (Denmark)

    Posch, Olaf

    This paper shows that non-linearities can generate time-varying and asymmetric risk premia over the business cycle. These (empirical) key features become relevant and asset market implications improve substantially when we allow for non-normalities in the form of rare disasters. We employ explicit...... solutions of dynamic stochastic general equilibrium models, including a novel solution with endogenous labor supply, to obtain closed-form expressions for the risk premium in production economies. We find that the curvature of the policy functions affects the risk premium through controlling the individual......'s effective risk aversion....

  4. Generalized magnetofluid connections in relativistic magnetohydrodynamics.

    Science.gov (United States)

    Asenjo, Felipe A; Comisso, Luca

    2015-03-20

    The concept of magnetic connections is extended to nonideal relativistic magnetohydrodynamical plasmas. Adopting a general set of equations for relativistic magnetohydrodynamics including thermal-inertial, thermal electromotive, Hall, and current-inertia effects, we derive a new covariant connection equation showing the existence of generalized magnetofluid connections that are preserved during the dissipationless plasma dynamics. These connections are intimately linked to a general antisymmetric tensor that unifies the electromagnetic and fluid fields, allowing the extension of the magnetic connection notion to a much broader concept.

  5. On generalized operator quasi-equilibrium problems

    Science.gov (United States)

    Kum, Sangho; Kim, Won Kyu

    2008-09-01

    In this paper, we will introduce the generalized operator equilibrium problem and generalized operator quasi-equilibrium problem which generalize the operator equilibrium problem due to Kazmi and Raouf [K.R. Kazmi, A. Raouf, A class of operator equilibrium problems, J. Math. Anal. Appl. 308 (2005) 554-564] into multi-valued and quasi-equilibrium problems. Using a Fan-Browder type fixed point theorem in [S. Park, Foundations of the KKM theory via coincidences of composites of upper semicontinuous maps, J. Korean Math. Soc. 31 (1994) 493-519] and an existence theorem of equilibrium for 1-person game in [X.-P. Ding, W.K. Kim, K.-K. Tan, Equilibria of non-compact generalized games with L*-majorized preferences, J. Math. Anal. Appl. 164 (1992) 508-517] as basic tools, we prove new existence theorems on generalized operator equilibrium problem and generalized operator quasi-equilibrium problem which includes operator equilibrium problems.

  6. General relativistic observables of the GRAIL mission

    CERN Document Server

    Turyshev, Slava G; Sazhin, Mikhail V

    2012-01-01

    We present a realization of astronomical relativistic reference frames in the solar system and its application to the GRAIL mission. We model the necessary spacetime coordinate transformations for light-trip time computations and address some practical aspects of the implementation of the resulting model. We develop all the relevant relativistic coordinate transformations that are needed to describe the motion of the GRAIL spacecraft and to compute all observable quantities. We take into account major relativistic effects contributing to the dual one-way range observable, which is derived from one-way signal travel times between the two GRAIL spacecraft. We develop a general relativistic model for this fundamental observable of GRAIL, accurate to 1 $\\mu$m. We develop and present a relativistic model for another key observable of this experiment, the dual one-way range-rate, accurate to 1 $\\mu$m/s. The presented formulation justifies the basic assumptions behind the design of the GRAIL mission. It may also be ...

  7. Local Thermal Equilibrium States in Relativistic Quantum Field Theory

    CERN Document Server

    Gransee, Michael

    2016-01-01

    It is well-known that thermal equilibrium states in quantum statistical mechanics and quantum field theory can be described in a mathematically rigorous manner by means of the so-called Kubo-Martin-Schwinger (KMS) condition, which is based on certain analyticity and periodicity properties of correlation functions. On the other hand, the characterization of non-equilibrium states which only locally have thermal properties still constitutes a challenge in quantum field theory. We discuss a recent proposal for characterization of such states by a generalized KMS condition. The connection of this proposal to a proposal by D. Buchholz, I. Ojima and H.-J. Roos for characterizing local thermal equilibrium states in quantum field theory is discussed.

  8. Stochastic oscillations of general relativistic disks

    CERN Document Server

    Harko, Tiberiu

    2012-01-01

    We analyze the general relativistic oscillations of thin accretion disks around compact astrophysical objects interacting with the surrounding medium through non-gravitational forces. The interaction with the external medium (a thermal bath) is modeled via a friction force, and a random force, respectively. The general equations describing the stochastically perturbed disks are derived by considering the perturbations of trajectories of the test particles in equatorial orbits, assumed to move along the geodesic lines. By taking into account the presence of a viscous dissipation and of a stochastic force we show that the dynamics of the stochastically perturbed disks can be formulated in terms of a general relativistic Langevin equation. The stochastic energy transport equation is also obtained. The vertical oscillations of the disks in the Schwarzschild and Kerr geometries are considered in detail, and they are analyzed by numerically integrating the corresponding Langevin equations. The vertical displacement...

  9. General Relativistic Effects in Atom Interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Dimopoulos, Savas; /Stanford U., Phys. Dept.; Graham, Peter W.; /SLAC /Stanford U., Phys. Dept.; Hogan, Jason M.; Kasevich, Mark A.; /Stanford U., Phys. Dept.

    2008-03-17

    Atom interferometry is now reaching sufficient precision to motivate laboratory tests of general relativity. We begin by explaining the non-relativistic calculation of the phase shift in an atom interferometer and deriving its range of validity. From this we develop a method for calculating the phase shift in general relativity. This formalism is then used to find the relativistic effects in an atom interferometer in a weak gravitational field for application to laboratory tests of general relativity. The potentially testable relativistic effects include the non-linear three-graviton coupling, the gravity of kinetic energy, and the falling of light. We propose experiments, one currently under construction, that could provide a test of the principle of equivalence to 1 part in 10{sup 15} (300 times better than the present limit), and general relativity at the 10% level, with many potential future improvements. We also consider applications to other metrics including the Lense-Thirring effect, the expansion of the universe, and preferred frame and location effects.

  10. General relativistic neutrino transport using spectral methods

    Science.gov (United States)

    Peres, Bruno; Penner, Andrew Jason; Novak, Jérôme; Bonazzola, Silvano

    2014-02-01

    We present a new code, Lorene's Ghost (for Lorene's gravitational handling of spectral transport) developed to treat the problem of neutrino transport in supernovae with the use of spectral methods. First, we derive the expression for the nonrelativistic Liouville operator in doubly spherical coordinates (r, θ, ϕ, ɛ, Θ, Φ), and further its general relativistic counterpart. We use the 3 + 1 formalism with the conformally flat approximation for the spatial metric, to express the Liouville operator in the Eulerian frame. Our formulation does not use any approximations when dealing with the angular arguments (θ, ϕ, Θ, Φ), and is fully energy-dependent. This approach is implemented in a spherical shell, using either Chebyshev polynomials or Fourier series as decomposition bases. It is here restricted to simplified collision terms (isoenergetic scattering) and to the case of a static fluid. We finish this paper by presenting test results using basic configurations, including general relativistic ones in the Schwarzschild metric, in order to demonstrate the convergence properties, the conservation of particle number and correct treatment of some general relativistic effects of our code. The use of spectral methods enables to run our test cases in a six-dimensional setting on a single processor.

  11. Generalized One-Dimensional Point Interaction in Relativistic and Non-relativistic Quantum Mechanics

    CERN Document Server

    Shigehara, T; Mishima, T; Cheon, T; Cheon, Taksu

    1999-01-01

    We first give the solution for the local approximation of a four parameter family of generalized one-dimensional point interactions within the framework of non-relativistic model with three neighboring $\\delta$ functions. We also discuss the problem within relativistic (Dirac) framework and give the solution for a three parameter family. It gives a physical interpretation for so-called high energy substantially differ between non-relativistic and relativistic cases.

  12. Relativistic astrophysics

    CERN Document Server

    Demianski, Marek

    2013-01-01

    Relativistic Astrophysics brings together important astronomical discoveries and the significant achievements, as well as the difficulties in the field of relativistic astrophysics. This book is divided into 10 chapters that tackle some aspects of the field, including the gravitational field, stellar equilibrium, black holes, and cosmology. The opening chapters introduce the theories to delineate gravitational field and the elements of relativistic thermodynamics and hydrodynamics. The succeeding chapters deal with the gravitational fields in matter; stellar equilibrium and general relativity

  13. Leibnizian relationalism for general relativistic physics

    CERN Document Server

    Vassallo, Antonio

    2016-01-01

    An ontology of Leibnizian relationalism, consisting in distance relations among sparse matter points and their change only, is well recognized as a serious option in the context of classical mechanics. In this paper, we investigate how this ontology fares when it comes to general relativistic physics. Using a Humean strategy, we regard the gravitational field as a means to represent the overall change in the distance relations among point particles in a way that achieves the best combination of being simple and being informative.

  14. Local thermodynamical equilibrium and the β frame for a quantum relativistic fluid

    Energy Technology Data Exchange (ETDEWEB)

    Becattini, Francesco; Grossi, Eduardo [Universita di Firenze, Florence (Italy); INFN, Florence (Italy); Bucciantini, Leda [Dipartimento di Fisica, Universita di Pisa (Italy); INFN, Pisa (Italy); Tinti, Leonardo [Jan Kochanowski University, Kielce (Poland)

    2015-05-15

    We discuss the concept of local thermodynamical equilibrium in relativistic hydrodynamics in flat spacetime in a quantum statistical framework without an underlying kinetic description, suitable for strongly interacting fluids. We show that the appropriate definition of local equilibrium naturally leads to the introduction of a relativistic hydrodynamical frame in which the four-velocity vector is the one of a relativistic thermometer at equilibrium with the fluid, parallel to the inverse temperature four-vector β, which then becomes a primary quantity. We show that this frame is the most appropriate for the expansion of the stress-energy tensor from local thermodynamical equilibrium and that therein the local laws of thermodynamics take on their simplest form. We discuss the difference between the β frame and Landau frame and present an instance where they differ. (orig.)

  15. Local thermodynamical equilibrium and the β frame for a quantum relativistic fluid

    Energy Technology Data Exchange (ETDEWEB)

    Becattini, Francesco, E-mail: becattini@fi.infn.it [Università di Firenze and INFN Sezione di Firenze, Florence (Italy); Bucciantini, Leda, E-mail: leda.bucciantini@df.unipi.it [Dipartimento di Fisica dell’Università di Pisa and INFN, 56127, Pisa (Italy); Grossi, Eduardo, E-mail: grossi@fi.infn.it [Università di Firenze and INFN Sezione di Firenze, Florence (Italy); Tinti, Leonardo, E-mail: dr.leonardo.tinti@gmail.com [Jan Kochanowski University, Kielce (Poland)

    2015-05-05

    We discuss the concept of local thermodynamical equilibrium in relativistic hydrodynamics in flat spacetime in a quantum statistical framework without an underlying kinetic description, suitable for strongly interacting fluids. We show that the appropriate definition of local equilibrium naturally leads to the introduction of a relativistic hydrodynamical frame in which the four-velocity vector is the one of a relativistic thermometer at equilibrium with the fluid, parallel to the inverse temperature four-vector β, which then becomes a primary quantity. We show that this frame is the most appropriate for the expansion of the stress-energy tensor from local thermodynamical equilibrium and that therein the local laws of thermodynamics take on their simplest form. We discuss the difference between the β frame and Landau frame and present an instance where they differ.

  16. A Constructive Generalization of Nash Equilibrium

    CERN Document Server

    Huang, Xiaofei

    2009-01-01

    In a society of multiple individuals, if everybody is only interested in maximizing his own payoff, will there exist any equilibrium for the society? John Nash proved more than 50 years ago that an equilibrium always exists such that nobody would benefit from unilaterally changing his strategy. Nash Equilibrium is a central concept in game theory, which offers the mathematical foundation for social science and economy. However, the original definition is declarative without including a solution to find them. It has been found later that it is computationally difficult to find a Nash equilibrium. Furthermore, a Nash equilibrium may be unstable, sensitive to the smallest variation of payoff functions. Making the situation worse, a society with selfish individuals can have an enormous number of equilibria, making it extremely hard to find out the global optimal one. This paper offers a constructive generalization of Nash equilibrium to cover the case when the selfishness of individuals are reduced to lower level...

  17. General relativistic neutrino transport using spectral methods

    CERN Document Server

    Peres, Bruno; Novak, Jerome; Bonazzola, Silvano

    2014-01-01

    We present a new code, Lorene's Ghost (for Lorene's gravitational handling of spectral transport) developed to treat the problem of neutrino transport in supernovae with the use of spectral methods. First, we derive the expression for the nonrelativistic Liouville operator in doubly spherical coordinates (r, theta, phi, epsilon, Theta, Phi)$, and further its general relativistic counterpart. We use the 3 + 1 formalism with the conformally flat approximation for the spatial metric, to express the Liouville operator in the Eulerian frame. Our formulation does not use any approximations when dealing with the angular arguments (theta, phi, Theta, Phi), and is fully energy-dependent. This approach is implemented in a spherical shell, using either Chebyshev polynomials or Fourier series as decomposition bases. It is here restricted to simplified collision terms (isoenergetic scattering) and to the case of a static fluid. We finish this paper by presenting test results using basic configurations, including general r...

  18. OPTIMAL RESOURCE ALLOCATION IN GENERAL COURNOTCOMPETITIVE EQUILIBRIUM

    OpenAIRE

    Ervik, Inger Sommerfelt; Soegaard, Christian

    2013-01-01

    Conventional economic theory stipulates that output in Cournot competition is too low relative to that which is attained in perfect competition. We revisit this result in a General Cournot-competitive Equilibrium model with two industries that di er only in terms of productivity. We show that in general equilibrium, the more ecient industry produces too little and the less ecient industry produces too much compared to an optimal scenario with perfect competition.

  19. A General Quadrature Solution for Relativistic, Non-relativistic, and Weakly-Relativistic Rocket Equations

    CERN Document Server

    Bruce, Adam L

    2015-01-01

    We show the traditional rocket problem, where the ejecta velocity is assumed constant, can be reduced to an integral quadrature of which the completely non-relativistic equation of Tsiolkovsky, as well as the fully relativistic equation derived by Ackeret, are limiting cases. By expanding this quadrature in series, it is shown explicitly how relativistic corrections to the mass ratio equation as the rocket transitions from the Newtonian to the relativistic regime can be represented as products of exponential functions of the rocket velocity, ejecta velocity, and the speed of light. We find that even low order correction products approximate the traditional relativistic equation to a high accuracy in flight regimes up to $0.5c$ while retaining a clear distinction between the non-relativistic base-case and relativistic corrections. We furthermore use the results developed to consider the case where the rocket is not moving relativistically but the ejecta stream is, and where the ejecta stream is massless.

  20. Radial equilibrium of relativistic particle bunches in plasma wakefield accelerators

    CERN Document Server

    Lotov, K V

    2016-01-01

    Drive particle beams in linear or weakly nonlinear regimes of the plasma wakefield accelerator quickly reach a radial equilibrium with the wakefield, which is described in detail for the first time. The equilibrium beam state and self-consistent wakefields are obtained by combining analytical relationships, numerical integration, and first-principle simulations. In the equilibrium state, the beam density is strongly peaked near the axis, the beam radius is constant along the beam, and longitudinal variation of the focusing strength is balanced by varying beam emittance. The transverse momentum distribution of beam particles depends on the observation radius and is neither separable, nor Gaussian.

  1. Status of Chemical Equilibrium in Relativistic Heavy Ion Collisions

    CERN Document Server

    Cleymans, Jean

    2009-01-01

    Recent work on chemical equilibrium in heavy ion collisions is reviewed. The energy dependence of thermal parameters is discussed. The centrality dependence of thermal parameters at SPS energies is presented.

  2. Status of chemical equilibrium in relativistic heavy-ion collisions

    Indian Academy of Sciences (India)

    J Cleymans

    2003-04-01

    Recent work on chemical equilibrium in heavy-ion collisions is reviewed. The energy dependence of thermal parameters is discussed. The centrality dependence of thermal parameters at SPS energies is presented.

  3. Slowly Rotating General Relativistic Superfluid Neutron Stars

    CERN Document Server

    Andersson, N

    2001-01-01

    We present a general formalism to treat slowly rotating general relativistic superfluid neutron stars. As a first approximation, their matter content can be described in terms of a two-fluid model, where one fluid is the neutron superfluid, which is believed to exist in the core and inner crust of mature neutron stars, and the other fluid represents a conglomerate of all other constituents (crust nuclei, protons, electrons, etc.). We obtain a system of equations, good to second-order in the rotational velocities, that determines the metric and the matter variables, irrespective of the equation of state for the two fluids. In particular, allowance is made for the so-called entrainment effect, whereby the momentum of one constituent (e.g. the neutrons) carries along part of the mass of the other constituent. As an illustration of the developed framework, we consider a simplified equation of state for which the two fluids are described by different polytropes. We determine numerically the effects of the two flui...

  4. Relativistic Arquimedes law for fast moving bodies and the general-relativistic resolution of the "submarine paradox"

    CERN Document Server

    Matsas, G E A

    2003-01-01

    We investigate and solve in the context of General Relativity the apparent paradox which appears when bodies floating in a background fluid are set in relativistic motion. Suppose some macroscopic body, say, a submarine designed to lie just in equilibrium when it rests (totally) immersed in a certain background fluid. The puzzle arises when different observers are asked to describe what is expected to happen when the submarine is given some high velocity parallel to the direction of the fluid surface. On the one hand, according to observers at rest with the fluid, the submarine would contract and, thus, sink as a consequence of the density increase. On the other hand, mariners at rest with the submarine using an analogous reasoning for the fluid elements would reach the opposite conclusion. The general relativistic extension of the Arquimedes law for moving bodies shows that the submarine sinks.

  5. General Equilibrium Models: Improving the Microeconomics Classroom

    Science.gov (United States)

    Nicholson, Walter; Westhoff, Frank

    2009-01-01

    General equilibrium models now play important roles in many fields of economics including tax policy, environmental regulation, international trade, and economic development. The intermediate microeconomics classroom has not kept pace with these trends, however. Microeconomics textbooks primarily focus on the insights that can be drawn from the…

  6. Micro Data and General Equilibrium Models

    DEFF Research Database (Denmark)

    Browning, Martin; Hansen, Lars Peter; Heckman, James J.

    1999-01-01

    Dynamic general equilibrium models are required to evaluate policies applied at the national level. To use these models to make quantitative forecasts requires knowledge of an extensive array of parameter values for the economy at large. This essay describes the parameters required for different ...

  7. A SOLUTION OF A GENERAL EQUILIBRIUM PROBLEM

    Institute of Scientific and Technical Information of China (English)

    H.R. SAHEBI; A. RAZANI

    2013-01-01

    Under the framework of a real Hilbert space, we introduce a new iterative method for finding a common element of the set of solution of a general equilibrium problem and the set of fixed points of a nonexpansive semigroup. Moreover, a numerical example is presented. This example grantee the main result of the paper.

  8. General Relativistic Simulations of the Collapsar Scenario

    CERN Document Server

    DeBrye, N; Aloy, M A; Font, J A

    2013-01-01

    We are exploring the viability of the collapsar model for long-soft gamma-ray bursts. For this we perform state-of-the-art general relativistic hydrodynamic simulations in a dynamically evolving space-time with the CoCoNuT code. We start from massive low metallicity stellar models evolved up to core gravitational instability, and then follow the subsequent evolution until the system collapses forming a compact remnant. A preliminary study of the collapse outcome is performed by varying the typical parameters of the scenario, such as the initial stellar mass, metallicity, and rotational profile of the stellar progenitor. 1D models (without rotation) have been used to test our newly developed neutrino leakage scheme. This is a fundamental piece of our approach as it allows the central remnant (in all cases considered, a metastable high-mass neutron star) to cool down, eventually collapsing to a black hole. In two dimensions, we show that sufficiently fast rotating cores lead to the formation of Kerr black holes...

  9. Generalized Convective Quasi-Equilibrium Closure

    Science.gov (United States)

    Yano, Jun-Ichi; Plant, Robert

    2016-04-01

    Arakawa and Schubert proposed convective quasi-equilibrium as a basic principle for closing their spectrum mass-flux convection parameterization. In deriving this principle, they show that the cloud work function is a key variable that controls the growth of convection. Thus, this closure hypothesis imposes a steadiness of the cloud work function tendency. This presentation shows how this principle can be generalized so that it can also encompasses both the CAPE and the moisture-convergence closures. Note that the majority of the current mass-flux convection parameterization invokes a CAPE closure, whereas the moisture-convergence closure was extremely popular historically. This generalization, in turn, includes both closures as special cases of convective quasi-equilibrium. This generalization further suggests wide range of alternative possibilities for convective closure. In general, a vertical integral of any function depending on both large-scale and convective-scale variables can be adopted as an alternative closure variables, leading to an analogous formulation as Arakawa and Schubert's convective quasi-equilibrium formulation. Among those, probably the most fascinating possibility is to take a vertical integral of the convective-scale moisture for the closure. Use of a convective-scale variable for closure has a particular appeal by not suffering from a loss of predictability of any large-scale variables. That is a main problem with any of the current convective closures, not only for the moisture-convergence based closure as often asserted.

  10. General relativistic observables for the ACES experiment

    CERN Document Server

    Turyshev, Slava G; Toth, Viktor T

    2015-01-01

    We develop a high-precision model for relativistic observables of the Atomic Clock Ensemble in Space (ACES) experiment on the International Space Station (ISS). We develop all relativistic coordinate transformations that are needed to describe the motion of ACES in Earth orbit and to compute observable quantities. We analyze the accuracy of the required model as it applies to the proper-to-coordinate time transformations, light time equation, and spacecraft equations of motion. We consider various sources of nongravitational noise and their effects on ACES. We estimate the accuracy of orbit reconstruction that is needed to satisfy the ACES science objectives. Based on our analysis, we derive models for the relativistic observables of ACES, which also account for the contribution of atmospheric drag on the clock rate. We include the Earth's oblateness coefficient $J_2$ and the effects of major nongravitational forces on the orbit of the ISS. We demonstrate that the ACES reference frame is pseudo-inertial at th...

  11. General relativistic tidal heating for Moller pseudotensor

    CERN Document Server

    So, Lau Loi

    2015-01-01

    Thorne elucidated that the relativistic tidal heating is the same as the Newtonian theory. Moreover, Thorne also claimed that the tidal heating is independent of how one localizes gravitational energy and is unambiguously given by a certain formula. Purdue and Favata calculated the tidal heating for different classical pseudotensors including Moller and obtained the results all matched with the Newtonian perspective. After re-examined this Moller pseudotensor, we find that there does not exist any tidal heating value. Thus we claim that the relativistic tidal heating is pseudotensor independent under the condition that if the peusdotensor is a Freud typed superpotential.

  12. Immigration and Outsourcing: A General Equilibrium Analysis

    OpenAIRE

    Subhayu Bandoyopadhyay; Wall, Howard J.

    2006-01-01

    This paper analyzes the issues of immigration and outsourcing in a general-equilibrium model of international factor mobility. In our model, legal immigration is controlled through a quota, while outsourcing is determined both by the firms (in response to market conditions) and through policy-imposed barriers. A loosening of the immigration quota reduces outsourcing, enriches capitalists, leads to losses for native workers, and raises national income. If the nation targets an exogenously dete...

  13. General relativistic aspects of ferromagneto-fluid

    Energy Technology Data Exchange (ETDEWEB)

    Asgekar, G.G.; Patwardhan, C.G.

    1988-03-01

    The implications of Bianchi identities pertaining to the spacetime of relativistic ferrofluid with infinite conductivity and variable magnetic permeability are investigated. Some kinematical and dynamical corollaries emerging out of a preferred geometrical symmetry called an isometry with respect to the flow vector and the magnetic field vector are developed.

  14. General relativistic aspects of ferromagneto-fluid.

    Science.gov (United States)

    Asgekar, G. G.; Patwardhan, C. G.

    1988-03-01

    The implications of Bianchi identities pertaining to the spacetime of relativistic ferrofluid with infinite conductivity and variable magnetic permeability are investigated. Some kinematical and dynamical corollaries emerging out of a preferred geometrical symmetry called an isometry with respect to the flow vector and the magnetic field vector are developed.

  15. General relativistic spectra of accretion disks around rotating neutron stars

    CERN Document Server

    Bhattacharya, S; Thampan, A V

    2000-01-01

    General relativistic spectra from accretion disks around rotating neutron stars in the appropriate space-time geometry for several different equation of state, spin rates and mass of the compact object have been computed. The analysis involves the computation of the relativistically corrected radial temperature profiles and the effect of Doppler and gravitational red-shifts on the spectra. Light bending effects have been omitted for simplicity. The relativistic spectrum is compared with the Newtonian one and it is shown that the difference between the two is primarily due to the different radial temperature profile for the relativistic and Newtonian disk solutions. To facilitate direct comparison with observations, a simple empirical function has been presented which describes the numerically computed relativistic spectra well. This empirical function (which has three parameters including normalization) also describes the Newtonian spectrum adequately. Thus the function can in principle be used to distinguish...

  16. Cosmological Measurements with General Relativistic Galaxy Correlations

    CERN Document Server

    Raccanelli, Alvise; Bertacca, Daniele; Doré, Olivier; Durrer, Ruth

    2015-01-01

    We investigate the cosmological dependence and the constraining power of large-scale galaxy correlations, including all redshift-distortions, wide-angle, lensing and gravitational potential effects on linear scales. We analyze the cosmological information present in the lensing convergence and in the gravitational potential terms describing the so-called "relativistic effects," and we find that, while smaller than the information contained in intrinsic galaxy clustering, it is not negligible. We investigate how neglecting them does bias cosmological measurements performed by future spectroscopic and photometric large-scale surveys such as SKA and Euclid. We perform a Fisher analysis using the CLASS code, modified to include scale-dependent galaxy bias and redshift-dependent magnification and evolution bias. Our results show that neglecting relativistic terms introduces an error in the forecasted precision in measuring cosmological parameters of the order of a few tens of percent, in particular when measuring ...

  17. Newtonian and General Relativistic Models of Spherical Shells

    CERN Document Server

    Vogt, D

    2009-01-01

    A family of spherical shells with varying thickness is derived by using a simple Newtonian potential-density pair. Then, a particular isotropic form of a metric in spherical coordinates is used to construct a General Relativistic version of the Newtonian family of shells. The matter of these relativistic shells presents equal azimuthal and polar pressures, while the radial pressure is a constant times the tangential pressure. We also make a first study of stability of both the Newtonian and relativistic families of shells.

  18. A new three-dimensional general-relativistic hydrodynamics code

    Science.gov (United States)

    Baiotti, L.; Hawke, I.; Montero, P. J.; Rezzolla, L.

    We present a new three-dimensional general relativistic hydrodynamics code, the Whisky code. This code incorporates the expertise developed over the past years in the numerical solution of Einstein equations and of the hydrodynamics equations in a curved spacetime, and is the result of a collaboration of several European Institutes. We here discuss the ability of the code to carry out long-term accurate evolutions of the linear and nonlinear dynamics of isolated relativistic stars.

  19. A new three-dimensional general-relativistic hydrodynamics code

    CERN Document Server

    Baiotti, Luca; Montero, Pedro J; Rezzolla, Luciano

    2010-01-01

    We present a new three-dimensional general relativistic hydrodynamics code, the Whisky code. This code incorporates the expertise developed over the past years in the numerical solution of Einstein equations and of the hydrodynamics equations in a curved spacetime, and is the result of a collaboration of several European Institutes. We here discuss the ability of the code to carry out long-term accurate evolutions of the linear and nonlinear dynamics of isolated relativistic stars.

  20. General Relativistic Mean Field Theory for rotating nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Madokoro, Hideki [Kyushu Univ., Fukuoka (Japan). Dept. of Physics; Matsuzaki, Masayuki

    1998-03-01

    The {sigma}-{omega} model Lagrangian is generalized to an accelerated frame by using the technique of general relativity which is known as tetrad formalism. We apply this model to the description of rotating nuclei within the mean field approximation, which we call General Relativistic Mean Field Theory (GRMFT) for rotating nuclei. The resulting equations of motion coincide with those of Munich group whose formulation was not based on the general relativistic transformation property of the spinor fields. Some numerical results are shown for the yrast states of the Mg isotopes and the superdeformed rotational bands in the A {approx} 60 mass region. (author)

  1. HEROIC: 3D General Relativistic Radiative Postprocessor with Comptonization for Black Hole Accretion Discs

    CERN Document Server

    Narayan, Ramesh; Psaltis, Dimitrios; Sadowski, Aleksander

    2015-01-01

    We describe HEROIC, an upgraded version of the relativistic radiative post-processor code HERO described in a previous paper, but which now Includes Comptonization. HEROIC models Comptonization via the Kompaneets equation, using a quadratic approximation for the source function in the short characteristics radiation solver. It employs a simple form of accelerated lambda iteration to handle regions of high scattering opacity. In addition to solving for the radiation field, HEROIC also solves for the gas temperature by applying the condition of radiative equilibrium. We present benchmarks and tests of the Comptonization module in HEROIC with simple 1D and 3D scattering problems. We also test the ability of the code to handle various relativistic effects using model atmospheres and accretion flows in a black hole space-time. We present two applications of HEROIC to general relativistic MHD simulations of accretion discs. One application is to a thin accretion disc around a black hole. We find that the gas below ...

  2. A general relativistic signature in the galaxy bispectrum

    CERN Document Server

    Umeh, Obinna; Maartens, Roy; Clarkson, Chris

    2016-01-01

    Next-generation galaxy surveys will increasingly rely on the galaxy bispectrum to improve cosmological constraints, especially on primordial non-Gaussianity. A key theoretical requirement that remains to be developed is the analysis of general relativistic effects on the bispectrum, which arise from observing galaxies on the past lightcone. Here we compute for the first time all the local relativistic corrections to the bispectrum, from Doppler, gravitational potential and higher-order effects. For the galaxy bispectrum, the problem is much more complex than for the power spectrum, since we need the lightcone corrections at second order. Mode-coupling contributions at second order mean that relativistic corrections can be non-negligible at smaller scales than in the case of the power spectrum. In a primordial Gaussian universe, we show that the relativistic bispectrum for a moderately squeezed shape can differ from the Newtonian prediction by $\\sim 30\\%$ when the short modes are at the equality scale. For the...

  3. General equilibrium shape equations of polymer chains.

    Science.gov (United States)

    Zhang, Shengli; Zuo, Xianjun; Xia, Minggang; Zhao, Shumin; Zhang, Erhu

    2004-11-01

    The general equilibrium shape equations of polymer chains are analytically derived in this paper. This provides a unified description for many models, such as the well-known wormlike chain (WLC) model, the wormlike rod chain (WLRC) model, carbon nanotubes, and so on. Using the WLC model, we find that the pitch-to-radius ratio of coils, 4.443, agrees with Z-DNA, and the pitch-to-radius ratio from WLRC agrees with the data of B-DNA qualitatively. Using the general shape equations, we discuss a chiral model in which the solutions of straight, helical, and circular biopolymers are given, respectively. We also find that the model suggested by Helfrich [Langmuir 7, 567 (1991)] is very appropriate to describe B-DNA (or other biopolymers) if we choose the four phenomenological parameters as A=50 nm , C=60 nm(2) , alpha=40 nm(3) , and beta=50 nm(2) .

  4. Generalized Relativistic Chapman-Enskog Solution of the Boltzmann Equation

    CERN Document Server

    García-Perciante, A L; García-Colin, L S

    2007-01-01

    The Chapman-Enskog method of solution of the relativistic Boltzmann equation is generalized in order to admit a time-derivative term associated to the thermodynamic force in its first order solution. Both existence and uniqueness of such a solution are proved based on the standard theory of integral equations. The mathematical implications of the generalization here introduced are briefly explored.

  5. General relativistic polytropes with a repulsive cosmological constant

    Science.gov (United States)

    Stuchlík, Zdeněk; Hledík, Stanislav; Novotný, Jan

    2016-11-01

    Spherically symmetric equilibrium configurations of perfect fluid obeying a polytropic equation of state are studied in spacetimes with a repulsive cosmological constant. The configurations are specified in terms of three parameters—the polytropic index n , the ratio of central pressure and central energy density of matter σ , and the ratio of energy density of vacuum and central density of matter λ . The static equilibrium configurations are determined by two coupled first-order nonlinear differential equations that are solved by numerical methods with the exception of polytropes with n =0 corresponding to the configurations with a uniform distribution of energy density, when the solution is given in terms of elementary functions. The geometry of the polytropes is conveniently represented by embedding diagrams of both the ordinary space geometry and the optical reference geometry reflecting some dynamical properties of the geodesic motion. The polytropes are represented by radial profiles of energy density, pressure, mass, and metric coefficients. For all tested values of n >0 , the static equilibrium configurations with fixed parameters n , σ , are allowed only up to a critical value of the cosmological parameter λc=λc(n ,σ ). In the case of n >3 , the critical value λc tends to zero for special values of σ . The gravitational potential energy and the binding energy of the polytropes are determined and studied by numerical methods. We discuss in detail the polytropes with an extension comparable to those of the dark matter halos related to galaxies, i.e., with extension ℓ>100 kpc and mass M >1 012 M⊙ . For such largely extended polytropes, the cosmological parameter relating the vacuum energy to the central density has to be larger than λ =ρvac/ρc˜10-9. We demonstrate that the extension of the static general relativistic polytropic configurations cannot exceed the so-called static radius related to their external spacetime, supporting the idea

  6. A generally-relativistic gauge classification of the Dirac fields

    CERN Document Server

    Fabbri, Luca

    2016-01-01

    We consider generally-relativistic gauge transformations for the spinorial fields finding two mutually exclusive but together exhaustive classes in which fermions are placed adding supplementary information to the results obtained by Lounesto, and identifying quantities analogous to the momentum vector and the Pauli-Lubanski axial vector we discuss how our results are similar to those obtained by Wigner; by taking into account the most general Dirac equations we will investigate the consequences for the dynamics: and in particular we shall address the problem of getting the non-relativistic approximation in a consistent way. We are going to comment on extensions.

  7. Convex Decompositions of Thermal Equilibrium for Non-interacting Non-relativistic Particles

    Science.gov (United States)

    Chenu, Aurelia; Branczyk, Agata; Sipe, John

    2016-05-01

    We provide convex decompositions of thermal equilibrium for non-interacting non-relativistic particles in terms of localized wave packets. These quantum representations offer a new tool and provide insights that can help relate to the classical picture. Considering that thermal states are ubiquitous in a wide diversity of fields, studying different convex decompositions of the canonical ensemble is an interesting problem by itself. The usual classical and quantum pictures of thermal equilibrium of N non-interacting, non-relativistic particles in a box of volume V are quite different. The picture in classical statistical mechanics is about (localized) particles with a range of positions and velocities; in quantum statistical mechanics, one considers the particles (bosons or fermions) associated with energy eigenstates that are delocalized through the whole box. Here we provide a representation of thermal equilibrium in quantum statistical mechanics involving wave packets with a localized coordinate representation and an expectation value of velocity. In addition to derive a formalism that may help simplify particular calculations, our results can be expected to provide insights into the transition from quantum to classical features of the fully quantum thermal state.

  8. General relativistic Boltzmann equation, II: Manifestly covariant treatment

    NARCIS (Netherlands)

    Debbasch, F.; van Leeuwen, W.A.

    2009-01-01

    In a preceding article we presented a general relativistic treatment of the derivation of the Boltzmann equation. The four-momenta occurring in this formalism were all on-shell four-momenta, verifying the mass-shell restriction p(2) = m(2)c(2). Due to this restriction, the resulting Boltzmann equati

  9. General relativistic Boltzmann equation, II: Manifestly covariant treatment

    NARCIS (Netherlands)

    Debbasch, F.; van Leeuwen, W.A.

    2009-01-01

    In a preceding article we presented a general relativistic treatment of the derivation of the Boltzmann equation. The four-momenta occurring in this formalism were all on-shell four-momenta, verifying the mass-shell restriction p(2) = m(2)c(2). Due to this restriction, the resulting Boltzmann

  10. General Relativistic Radiative Transfer and GeneralRelativistic MHD Simulations of Accretion and Outflows of Black Holes

    Energy Technology Data Exchange (ETDEWEB)

    Fuerst, Steven V.; /KIPAC, Menlo Park; Mizuno, Yosuke; /USRA, Huntsville; Nishikawa, Ken-Ichi; /USRA, Huntsville /Alabama U., Huntsville; Wu, Kinwah; /Mullard Space Sci.

    2007-01-05

    We calculate the emission from relativistic flows in black hole systems using a fully general relativistic radiative transfer formulation, with flow structures obtained by general relativistic magneto-hydrodynamic simulations. We consider thermal free-free emission and thermal synchrotron emission. Bright filament-like features protrude (visually) from the accretion disk surface, which are enhancements of synchrotron emission where the magnetic field roughly aligns with the line-of-sight in the co-moving frame. The features move back and forth as the accretion flow evolves, but their visibility and morphology are robust. We propose that variations and drifts of the features produce certain X-ray quasi-periodic oscillations (QPOs) observed in black-hole X-ray binaries.

  11. Cherenkov loss factor of short relativistic bunches:general approach

    CERN Document Server

    Baturin, S S

    2013-01-01

    The interaction of short relativistic charged particle bunches with waveguides and other accelerator system components is a critical issue for the development of X-ray FELs (free electron lasers) and linear collider projects. Wakefield Cherenkov losses of short bunches have been studied previously for resistive wall, disk-loaded, corrugated and dielectric loaded waveguides. It was noted in various publications [1] that if the slowdown layer is thin, the Cherenkov loss factor of a short bunch does not depend on the guiding system material and is a constant for any given transverse cross section dimensions of the waveguides. In this paper, we consider a new approach to the analysis of loss factors for relativistic short bunches and formulate a general integral relation that allows calculation of the loss factor for a short relativistic bunch passing an arbitrary waveguide system. The loss factors calculated by this new method for various types of waveguides with arbitrary thickness slowdown layers, including in...

  12. General Equilibrium in a Nutshell: An Explicit Function Example.

    Science.gov (United States)

    Yunker, James A.

    1998-01-01

    Describes a general equilibrium model that fills the gap between the general function models described in price-theory textbooks and the numerical practice of general equilibrium analysis used in contemporary policy assessment. This model uses explicit mathematical forms but general parameter values. Includes graphs and statistical tables. (MJP)

  13. Causal Stability Conditions for General Relativistic Spacetimes

    CERN Document Server

    Howard, E M

    2016-01-01

    A brief overview of some open questions in general relativity with important consequences for causality theory is presented, aiming to a better understanding of the causal structure of the spacetime. Special attention is accorded to the problem of fundamental causal stability conditions. Several questions are raised and some of the potential consequences of recent results regarding the causality problem in general relativity are presented. A key question is whether causality violating regions are locally allowed. The new concept of almost stable causality is introduced; meanwhile, related conditions and criteria for the stability and almost stability of the causal structure are discussed.

  14. TOPICAL REVIEW: General relativistic boson stars

    CERN Document Server

    Schunck, Franz E

    2008-01-01

    There is accumulating evidence that (fundamental) scalar fields may exist in Nature. The gravitational collapse of such a boson cloud would lead to a boson star (BS) as a new type of a compact object. Similarly as for white dwarfs and neutron stars, there exists a limiting mass, below which a BS is stable against complete gravitational collapse to a black hole. According to the form of the self-interaction of the basic constituents and the spacetime symmetry, we can distinguish mini-, axidilaton, soliton, charged, oscillating and rotating BSs. Their compactness prevents a Newtonian approximation, however, modifications of general relativity, as in the case of Jordan-Brans-Dicke theory as a low energy limit of strings, would provide them with gravitational memory. In general, a BS is a compact, completely regular configuration with structured layers due to the anisotropy of scalar matter, an exponentially decreasing 'halo', a critical mass inversely proportional to constituent mass, an effective radius, and a ...

  15. TOPICAL REVIEW: General relativistic boson stars

    Science.gov (United States)

    Schunck, Franz E.; Mielke, Eckehard W.

    2003-10-01

    There is accumulating evidence that (fundamental) scalar fields may exist in nature. The gravitational collapse of such a boson cloud would lead to a boson star (BS) as a new type of a compact object. As with white dwarfs and neutron stars, a limiting mass exists similarly, below which a BS is stable against complete gravitational collapse to a black hole. According to the form of the self-interaction of the basic constituents and spacetime symmetry, we can distinguish mini-, axidilaton, soliton, charged, oscillating and rotating BSs. Their compactness prevents a Newtonian approximation; however, modifications of general relativity, as in the case of Jordan Brans Dicke theory as a low-energy limit of strings, would provide them with gravitational memory. In general, a BS is a compact, completely regular configuration with structured layers due to the anisotropy of scalar matter, an exponentially decreasing 'halo', a critical mass inversely proportional to the constituent mass, an effective radius and a large particle number. Due to the Heisenberg principle, a completely stable branch exists, and as a coherent state, it allows for rotating solutions with quantized angular momentum. In this review, we concentrate on the fascinating possibilities of detecting the various subtypes of (excited) BSs: possible signals include gravitational redshift and (micro-)lensing, emission of gravitational waves, or, in the case of a giant BS, its dark matter contribution to the rotation curves of galactic halos.

  16. Entropy Production and Equilibrium Conditions of General-Covariant Spin Systems

    Directory of Open Access Journals (Sweden)

    Wolfgang Muschik

    2015-12-01

    Full Text Available In generalizing the special-relativistic one-component version of Eckart’s continuum thermodynamics to general-relativistic space-times with Riemannian or post-Riemannian geometry as presented by Schouten (Schouten, J.A. Ricci-Calculus, 1954 and Blagojevic (Blagojevic, M. Gauge Theories of Gravitation, 2013 we consider the entropy production and other thermodynamical quantities, such as the entropy flux and the Gibbs fundamental equation. We discuss equilibrium conditions in gravitational theories, which are based on such geometries. In particular, thermodynamic implications of the non-symmetry of the energy-momentum tensor and the related spin balance equations are investigated, also for the special case of general relativity.

  17. General Relativistic White Dwarfs and Their Astrophysical Implications

    CERN Document Server

    Boshkayev, Kuantay; Ruffini, Remo; Siutsou, Ivan

    2014-01-01

    We consider applications of general relativistic uniformly-rotating white dwarfs to several astrophysical phenomena related to the spin-up and the spin-down epochs and to delayed type Ia supernova explosions of super-Chandrasekhar white dwarfs, where we estimate the "spinning down" lifetime due to magnetic-dipole braking. In addition, we describe the physical properties of Soft Gamma Repeaters and Anomalous X-Ray Pulsars as massive rapidly-rotating highly-magnetized white dwarfs. Particularly we consider one of the so-called low-magnetic-field magnetars SGR 0418+5729 as a massive rapidly-rotating highly-magnetized white dwarf and give bounds for the mass, radius, moment of inertia, and magnetic field by requiring the general relativistic uniformly-rotating configurations to be stable.

  18. General relativistic white dwarfs and their astrophysical implications

    Energy Technology Data Exchange (ETDEWEB)

    Boshkayev, Kuantay [Al-Farabi Kazakh National University, Almaty (Kazakhstan); Rueda, Jorge A.; Ruffini, Remo [Sapienza University of Rome, Rome (Italy); Siutsou, Ivan [ICRANet, Square of Republic, Pescara (Italy)

    2014-09-15

    We consider applications of general relativistic uniformly-rotating white dwarfs to several astrophysical phenomena related to the spin-up and the spin-down epochs and to delayed type Ia supernova explosions of super-Chandrasekhar white dwarfs, where we estimate the 'spinning down' lifetime due to magnetic-dipole braking. In addition, we describe the physical properties of Soft Gamma Repeaters and Anomalous X-Ray Pulsars as massive rapidly-rotating highly-magnetized white dwarfs. Particularly we consider one of the so-called low-magnetic-field magnetars SGR 0418+5729 as a massive rapidly-rotating highly- magnetized white dwarf and give bounds for the mass, radius, moment of inertia, and magnetic field by requiring the general relativistic uniformly rotating configurations to be stable.

  19. General Relativistic Transfer Equation on a Kerr Black Hole

    Science.gov (United States)

    Zannias, T.

    1998-12-01

    The general relativistic transfer equation describing the interaction of a massless gas with a hot plasma is analyzed on the background of a Kerr black hole. On physical grounds we single out two natural orthonormal frames relative to which the radiative transfer equation takes its simplest form. First the field of the local rest frame defined by the plasma and secondly the local rest frame associated with Bardeens-ZAMOS observers. Applications of the formalism to accretion problems will also briefly discussed.

  20. A new spherically symmetric general relativistic hydrodynamical code

    CERN Document Server

    Romero, J V; Martí, J M; Miralles, J A; Romero, Jose V; Ibanez, Jose M; Marti, Jose M; Miralles, Juan A

    1995-01-01

    In this paper we present a full general relativistic one-dimensional hydro-code which incorporates a modern high-resolution shock-capturing algorithm, with an approximate Riemann solver, for the correct modelling of formation and propagation of strong shocks. The efficiency of this code in treating strong shocks is demonstrated by some numerical experiments. The interest of this technique in several astrophysical scenarios is discussed.

  1. A General Thermal Equilibrium Discharge Flow Model

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Min-fu; ZHANG; Dong-xu; LV; Yu-feng

    2015-01-01

    In isentropic and thermal equilibrium assumptions,a discharge flow model was derived,which unified the rules of normal temperature water discharge,high temperature and high pressure water discharge,two-phase critical flow,saturated steam and superheated steam critical

  2. The system of generalized set-valued equilibrium problems

    Directory of Open Access Journals (Sweden)

    Peng Jian-Wen

    2006-01-01

    Full Text Available We introduce new and interesting model of system of generalized set-valued equilibrium problems which generalizes and unifies the system of set-valued equilibrium problems, the system of generalized implicit vector variational inequalities, the system of generalized vector and vector-like variational inequalities introduced by Ansari et al. (2002, the system of generalized vector variational inequalities presented by Allevi et al. (2001, the system of vector equilibrium problems and the system of vector variational inequalities given by Ansari et al. (2000, the system of scalar variational inequalities presented by Ansari Yao (1999, 2000, Bianchi (1993, Cohen and Caplis (1988, Konnov (2001, and Pang (1985, the system of Ky-Fan variational inequalities proposed bt Deguire et al. (1999 as well as a variety of equilibrium problems in the literature. Several existence results of a solution for the system of generalized set-valued equilibrium problems will be shown.

  3. Magnetic structures propagating in non-equilibrium relativistic plasma of pulsar wind nebulae

    Science.gov (United States)

    Petrov, A. E.; Bykov, A. M.

    2016-11-01

    The kinetic model of highly non-equilibrium relativistic electron-positron plasma is used to study dynamical magnetic structures in pulsar wind nebulae (PWNe). The evolution equation which describes a propagation of a long-wavelength magnetosonic type perturbation of small but finite amplitude is derived. The wavelength is assumed to be longer than the scattering length of the background positrons and electrons. The rates of scattering of electrons and positrons by the stochastic magnetic field fluctuations are distinguished but the difference is supposed to be small compared with the gyrofrequencies of particles. The phase velocity, the dissipation rate and the dispersion length of the magnetic pulse are studied as the functions of plasma parameters and the scattering rates of electrons and positrons. The model being confronted to observations can help to determine the pulsar wind composition, particle distribution and non-thermal pressure in PWNe.

  4. Relativistic heavy ion collisions with realistic non-equilibrium mean fields

    CERN Document Server

    Fuchs, C; Wolter, H H

    1996-01-01

    We study the influence of non-equilibrium phase space effects on the dynamics of heavy ion reactions within the relativistic BUU approach. We use realistic Dirac-Brueckner-Hartree-Fock (DBHF) mean fields determined for two-Fermi-ellipsoid configurations, i.e. for colliding nuclear matter, in a local phase space configuration approximation (LCA). We compare to DBHF mean fields in the local density approximation (LDA) and to the non-linear Walecka model. The results are further compared to flow data of the reaction Au on Au at 400 MeV per nucleon measured by the FOPI collaboration. We find that the DBHF fields reproduce the experiment if the configuration dependence is taken into account. This has also implications on the determination of the equation of state from heavy ion collisions.

  5. Strong Duality and Optimality Conditions for Generalized Equilibrium Problems

    Directory of Open Access Journals (Sweden)

    D. H. Fang

    2013-01-01

    Full Text Available We consider a generalized equilibrium problem involving DC functions. By using the properties of the epigraph of the conjugate functions, some sufficient and/or necessary conditions for the weak and strong duality results and optimality conditions for generalized equilibrium problems are provided.

  6. Parameter Estimation for a Computable General Equilibrium Model

    DEFF Research Database (Denmark)

    Arndt, Channing; Robinson, Sherman; Tarp, Finn

    2002-01-01

    We introduce a maximum entropy approach to parameter estimation for computable general equilibrium (CGE) models. The approach applies information theory to estimating a system of non-linear simultaneous equations. It has a number of advantages. First, it imposes all general equilibrium constraints...

  7. General Economic Equilibrium: Purpose, Analytic Techniques, Collective Choice

    Science.gov (United States)

    The lecture is designed to survey modern development of the theory of general equilibrium in a competitive economy and its role in the allocation of...by an evaluation of the needs for further development. The differing general equilibrium tradition in the German-language literature is summarized.

  8. Parameter Estimation for a Computable General Equilibrium Model

    DEFF Research Database (Denmark)

    Arndt, Channing; Robinson, Sherman; Tarp, Finn

    We introduce a maximum entropy approach to parameter estimation for computable general equilibrium (CGE) models. The approach applies information theory to estimating a system of nonlinear simultaneous equations. It has a number of advantages. First, it imposes all general equilibrium constraints...

  9. Description of the General Equilibrium Model of Ecosystem Services (GEMES)

    Science.gov (United States)

    Travis Warziniack; David Finnoff; Jenny Apriesnig

    2017-01-01

    This paper serves as documentation for the General Equilibrium Model of Ecosystem Services (GEMES). GEMES is a regional computable general equilibrium model that is composed of values derived from natural capital and ecosystem services. It models households, producing sectors, and governments, linked to one another through commodity and factor markets. GEMES was...

  10. General factorization scheme with application to relativistic Hermite polynomials

    CERN Document Server

    Rosu, H C; Obregón, O; Reyes, Marco A; Obregon, Octavio

    1995-01-01

    We present a sufficiently general factorization scheme of second-order linear differential equations having discrete (polynomial) indeces both in the coefficient of the first-derivative term and of the derivative-free one. We apply it to the relativistic Hermite equation in order to perform the factorization with respect to the polynomial degree confirming the factorization of Aldaya, Bisquert and Navarro-Salas, but also obtaining another slightly modified factorization, and to the Gegenbauer equation for the factorization with respect to the order. Moreover, by making use of Nagel's relation between Gegenbauer and relativistic Hermite polynomials we write down ladder-like operations with respect to the order for the latter ones, which are another interesting result of the paper.

  11. General Relativistic Smoothed Particle Hydrodynamics code developments: A progress report

    Science.gov (United States)

    Faber, Joshua; Silberman, Zachary; Rizzo, Monica

    2017-01-01

    We report on our progress in developing a new general relativistic Smoothed Particle Hydrodynamics (SPH) code, which will be appropriate for studying the properties of accretion disks around black holes as well as compact object binary mergers and their ejecta. We will discuss in turn the relativistic formalisms being used to handle the evolution, our techniques for dealing with conservative and primitive variables, as well as those used to ensure proper conservation of various physical quantities. Code tests and performance metrics will be discussed, as will the prospects for including smoothed particle hydrodynamics codes within other numerical relativity codebases, particularly the publicly available Einstein Toolkit. We acknowledge support from NSF award ACI-1550436 and an internal RIT D-RIG grant.

  12. Equation of State in a Generalized Relativistic Density Functional Approach

    CERN Document Server

    Typel, Stefan

    2015-01-01

    The basic concepts of a generalized relativistic density functional approach to the equation of state of dense matter are presented. The model is an extension of relativistic mean-field models with density-dependent couplings. It includes explicit cluster degrees of freedom. The formation and dissolution of nuclei is described with the help of mass shifts. The model can be adapted to the description of finite nuclei in order to study the effect of $\\alpha$-particle correlations at the nuclear surface on the neutron skin thickness of heavy nuclei. Further extensions of the model to include quark degrees of freedom or an energy dependence of the nucleon self-energies are outlined.

  13. HARM A Numerical Scheme for General Relativistic Magnetohydrodynamics

    CERN Document Server

    Gammie, C F; Tóth, G; Gammie, Charles F.; Kinney, Jonathan C. Mc

    2003-01-01

    We describe a conservative, shock-capturing scheme for evolving the equations of general relativistic magnetohydrodynamics. The fluxes are calculated using the Harten, Lax, and van Leer scheme. A variant of constrained transport, proposed earlier by T\\'oth, is used to maintain a divergence free magnetic field. Only the covariant form of the metric in a coordinate basis is required to specify the geometry. We describe code performance on a full suite of test problems in both special and general relativity. On smooth flows we show that it converges at second order. We conclude by showing some results from the evolution of a magnetized torus near a rotating black hole.

  14. General Equilibrium without Utility Functions: How far to go?

    DEFF Research Database (Denmark)

    Balasko, Yves; Tvede, Mich

    How far can we go in weakening the assumptions of the general equilibrium model? Existence of equilibrium, structural stability and finiteness of equilibria of regular economies, genericity of regular economies and an index formula for the equilibria of regular economies have been known not to re......How far can we go in weakening the assumptions of the general equilibrium model? Existence of equilibrium, structural stability and finiteness of equilibria of regular economies, genericity of regular economies and an index formula for the equilibria of regular economies have been known...... and the diffeomorphism of the equilibrium manifold with a Euclidean space; 2) the diffeomorphism of the set of no-trade equilibria with a Euclidean space; 3) the openness and genericity of the set of regular equilibria as a subset of the equilibrium manifold; 4) for small trade vectors, the uniqueness, regularity...

  15. General Equilibrium Theory with Market Frictions. Part I. Quantity Equilibrium with Rational Expectations.

    Science.gov (United States)

    1978-09-01

    general equilibrium model of an economy with market fritions. A market is said to have frictions if buyers and sellers have trouble finding each other, if it is costly for them to search for each other, and if it is costly to wait to buy or sell. Equilibrium is a stationary probability distribution over the set of possible time paths of states of the economy. This equilibrium reflects rational expectations if all agents know the stationary distribution of the variables they observe and if they exploit this information. Prices are fixed and are not necessarily equilibrium

  16. PEMAHAMAN DASAR ANALISIS MODEL COMPUTABLE GENERAL EQUILIBRIUM (CGE

    Directory of Open Access Journals (Sweden)

    Mardiyah Hayati

    2013-11-01

    Full Text Available Simple paper about basic understanding of computable general equilibrium aimed to give basic understanding about CGE. It consist of history of CGE, assumption of CGE model, excess and lack of CGE model, and creation of simple CGE model for closed economy. CGE model is suitable to be used for seeing impact of new policy implementation. It is because CGE model use general equilibrium in which this theory of general equilibrium explaining about inter-relation among markets in the economy system. CGE model was introduced in 1960s known as Johansen model. Next, it is expanded into various models such as: ORANI Model, General Trade Analysis Project (GTAP Model, and Applied General Equilibrium (AGE Model. In Indonesia, there are CGE ORANI Model, Wayang, Indonesia-E3 and IRCGE. CGE Model is created by assumption of perfect competition. Consumer maximizes utility, producer maximizes profit, and company maximizes zero profit condition.

  17. HERO - A 3D general relativistic radiative post-processor for accretion discs around black holes

    Science.gov (United States)

    Zhu, Yucong; Narayan, Ramesh; Sadowski, Aleksander; Psaltis, Dimitrios

    2015-08-01

    HERO (Hybrid Evaluator for Radiative Objects) is a 3D general relativistic radiative transfer code which has been tailored to the problem of analysing radiation from simulations of relativistic accretion discs around black holes. HERO is designed to be used as a post-processor. Given some fixed fluid structure for the disc (i.e. density and velocity as a function of position from a hydrodynamic or magnetohydrodynamic simulation), the code obtains a self-consistent solution for the radiation field and for the gas temperatures using the condition of radiative equilibrium. The novel aspect of HERO is that it combines two techniques: (1) a short-characteristics (SC) solver that quickly converges to a self-consistent disc temperature and radiation field, with (2) a long-characteristics (LC) solver that provides a more accurate solution for the radiation near the photosphere and in the optically thin regions. By combining these two techniques, we gain both the computational speed of SC and the high accuracy of LC. We present tests of HERO on a range of 1D, 2D, and 3D problems in flat space and show that the results agree well with both analytical and benchmark solutions. We also test the ability of the code to handle relativistic problems in curved space. Finally, we discuss the important topic of ray defects, a major limitation of the SC method, and describe our strategy for minimizing the induced error.

  18. Generalized Equilibrium Problems Related to Ky Fan Inequalities

    Directory of Open Access Journals (Sweden)

    Ionel Rovenţa

    2014-01-01

    Full Text Available We study a generalized equilibrium problem by using a nonsymmetric extension of Ky Fan’s inequality. As an application, we present a fixed point type algorithm inspired by a model from Tada and Takahashi (2007.

  19. Optimal resource allocation in General Cournot-competitive equilibrium

    OpenAIRE

    Sommerfelt Ervik, Inger; Soegaard, Christian

    2013-01-01

    Conventional economic theory stipulates that output in Cournot competition is too low relative to that which is attained in perfect competition. We revisit this result in a General Cournot-competitive Equilibrium model with two industries that differ only in terms of productivity. We show that in general equilibrium, the more efficient industry produces too little and the less efficient industry produces too much compared to an optimal scenario with perfect competition.

  20. The Chaotic General Economic Equilibrium Model and Monopoly

    Directory of Open Access Journals (Sweden)

    Vesna D. Jablanovic

    2012-09-01

    Full Text Available The basic aim of this study is to construct a relatively simple chaotic general economic equilibrium growth model that is capable of generating stable equilibrium, cycles, or chaos. An important example of general economic equilibrium is provided by monopolies. A key hypothesis of this study is based on the idea that the coefficient π = b mRS/m (α-1 (1+1/e mRT plays a crucial role in explaining local stability of the general equilibrium output, where, b: The coefficient of the quadratic marginal-cost function, m: The coefficient of the inverse demand function, mRS: The marginal rate of substitution, mRT: Marginal rate of transformation, α: The coefficient of the monopoly price growth, e: The coefficient of the price elasticity of demand.

  1. HEROIC: 3D general relativistic radiative post-processor with comptonization for black hole accretion discs

    Science.gov (United States)

    Narayan, Ramesh; Zhu, Yucong; Psaltis, Dimitrios; Saḑowski, Aleksander

    2016-03-01

    We describe Hybrid Evaluator for Radiative Objects Including Comptonization (HEROIC), an upgraded version of the relativistic radiative post-processor code HERO described in a previous paper, but which now Includes Comptonization. HEROIC models Comptonization via the Kompaneets equation, using a quadratic approximation for the source function in a short characteristics radiation solver. It employs a simple form of accelerated lambda iteration to handle regions of high scattering opacity. In addition to solving for the radiation field, HEROIC also solves for the gas temperature by applying the condition of radiative equilibrium. We present benchmarks and tests of the Comptonization module in HEROIC with simple 1D and 3D scattering problems. We also test the ability of the code to handle various relativistic effects using model atmospheres and accretion flows in a black hole space-time. We present two applications of HEROIC to general relativistic magnetohydrodynamics simulations of accretion discs. One application is to a thin accretion disc around a black hole. We find that the gas below the photosphere in the multidimensional HEROIC solution is nearly isothermal, quite different from previous solutions based on 1D plane parallel atmospheres. The second application is to a geometrically thick radiation-dominated accretion disc accreting at 11 times the Eddington rate. Here, the multidimensional HEROIC solution shows that, for observers who are on axis and look down the polar funnel, the isotropic equivalent luminosity could be more than 10 times the Eddington limit, even though the spectrum might still look thermal and show no signs of relativistic beaming.

  2. Observability of the General Relativistic Precession of Periastra in Exoplanets

    CERN Document Server

    Jordan, Andres

    2008-01-01

    The general relativistic precession rate of periastra in close-in exoplanets can be orders of magnitude larger than the magnitude of the same effect for Mercury. The realization that some of the close-in exoplanets have significant eccentricities raises the possibility that this precession might be detectable. We explore in this work the observability of the periastra precession using radial velocity and transit light curve observations. Our analysis is independent of the source of precession, which can also have significant contributions due to additional planets and tidal deformations. We find that precession of the periastra of the magnitude expected from general relativity can be detectable in timescales of <~ 10 years with current observational capabilities by measuring the change in the primary transit duration or in the time difference between primary and secondary transits. Radial velocity curves alone would be able to detect this precession for super-massive, close-in exoplanets orbiting inactive ...

  3. Equilibrium and stability of relativistic stars in extended theories of gravity

    Energy Technology Data Exchange (ETDEWEB)

    Wojnar, Aneta [Maria Curie-Sklodowska University, Institute of Physics, Lublin (Poland); Univ. di Monte S. Angelo, Napoli (Italy); Universita' di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Dipartimento di Fisica ' ' E. Pancini' ' , Naples (Italy); INFN, Napoli (Italy); Velten, Hermano [Universidade Federal do Espirito Santo (UFES), Vitoria (Brazil)

    2016-12-15

    We study static, spherically symmetric equilibrium configurations in extended theories of gravity (ETG) following the notation introduced by Capozziello et al. We calculate the differential equations for the stellar structure in such theories in a very generic form i.e., the Tolman-Oppenheimer-Volkoff generalization for any ETG is introduced. Stability analysis is also investigated with special focus on the particular example of scalar-tensor gravity. (orig.)

  4. Equilibrium and stability of relativistic stars in extended theories of gravity

    CERN Document Server

    Wojnar, Aneta

    2016-01-01

    We study static, spherically symmetric equilibrium configurations in extended theories of gravity (ETG) following the notation introduced by Capozziello et {\\it al}. We calculate the differential equations for the stellar structure in such theories in a very generic form i.e., the Tolman-Oppenheimer-Volkoff generalization for any ETG is introduced. Stability analysis is also investigated with special focus on the particular example of scalar-tensor gravity.

  5. Sedimentation equilibrium and the generalized Archimedes' principle.

    Science.gov (United States)

    Parola, Alberto; Buzzaccaro, Stefano; Secchi, Eleonora; Piazza, Roberto

    2013-03-21

    The buoyancy concept is critically re-examined for applications to dispersions of nano-particles, such as colloids, proteins, or macromolecules. It is shown that when the size of the buoyant particle is not too different (say, at most a factor of ten) from the size of the dispersed particles, new intriguing phenomena emerge, leading to the violation of the Archimedes' principle. The resulting buoyancy force depends not only on the volume of the particle and on the mass density of the dispersion, but also on the relative size of the particles, on their geometry, and on the interactions between the buoyant particle and the fluid. Explicit expressions for such a generalized Archimedes' principle are obtained and the results are tested against targeted experiments in colloidal dispersions.

  6. Sedimentation equilibrium and the generalized Archimedes' principle

    Science.gov (United States)

    Parola, Alberto; Buzzaccaro, Stefano; Secchi, Eleonora; Piazza, Roberto

    2013-03-01

    The buoyancy concept is critically re-examined for applications to dispersions of nano-particles, such as colloids, proteins, or macromolecules. It is shown that when the size of the buoyant particle is not too different (say, at most a factor of ten) from the size of the dispersed particles, new intriguing phenomena emerge, leading to the violation of the Archimedes' principle. The resulting buoyancy force depends not only on the volume of the particle and on the mass density of the dispersion, but also on the relative size of the particles, on their geometry, and on the interactions between the buoyant particle and the fluid. Explicit expressions for such a generalized Archimedes' principle are obtained and the results are tested against targeted experiments in colloidal dispersions.

  7. A Comment On Gintis's "The Dynamics of General Equilibrium"

    OpenAIRE

    Ennio Bilancini; Fabio Petri

    2008-01-01

    Gintis (2007, 'The Dynamics of General Equilibrium'', Economic Journal 117 (523) , 1280–1309) provides an agent-based model of a Walrasian economy where the tâtonnement is replaced by imitation. His simulations show that the economy converges to the Walrasian equilibrium. Gintis concludes that 1) his stability results provide some justification for the importance placed upon the Walrasian model, and 2) models allowing agents to imitate successful others lead to an economy with a reasonable le...

  8. Modelling general relativistic perfect fluids in field theoretic language

    CERN Document Server

    Mitskievich, N V

    1999-01-01

    Skew-symmetric massless fields, their potentials being $r$-forms, are close analogues of Maxwell's field (though the non-linear cases also should be considered). We observe that only two of them ($r=$2 and 3) automatically yield stress-energy tensors characteristic to normal perfect fluids. It is shown that they naturally describe both non-rotating ($r=2$) and rotating (then a combination of $r=2$ and $r=3$ fields is indispensable) general relativistic perfect fluids possessing every type of equations of state. Meanwile, a free $r=3$ field is completely equivalent to appearance of the cosmological term in Einstein's equations. Sound waves represent perturbations propagating on the background of the $r=2$ field. Some exotic properties of these two fields are outlined.

  9. General Relativistic Simulations of Magnetized Binary Neutron Stars

    Science.gov (United States)

    Giacomazzo, Bruno

    2011-04-01

    Binary neutron stars are among the most important sources of gravitational waves which are expected to be detected by the current or next generation of gravitational wave detectors, such as LIGO and Virgo, and they are also thought to be at the origin of very important astrophysical phenomena, such as short gamma-ray bursts. I will report on some recent results obtained using the fully general relativistic magnetohydrodynamic code Whisky in simulating equal-mass binary neutron star systems during the last phases of inspiral, merger and collapse to black hole surrounded by a torus. I will in particular describe how magnetic fields can affect the gravitational wave signal emitted by these sources and their possible role in powering short gamma-ray bursts.

  10. General Relativistic Simulations of Binary Neutron Star Mergers

    Science.gov (United States)

    Giacomazzo, Bruno; Rezzolla, Luciano; Baiotti, Luca; Link, David; Font, José A.

    2011-08-01

    Binary neutron star mergers are one of the possible candidates for the central engine of short gamma-ray bursts (GRBs) and they are also powerful sources of gravitational waves. We have used our fully general relativistic hydrodynamical code Whisky to investigate the merger of binary neutron star systems and we have in particular studied the properties of the tori that can be formed by these systems, their possible connection with the engine of short GRBs and the gravitational wave signals that detectors such as advanced LIGO will be able to detect. We have also shown how the mass of the torus varies as a function of the total mass of the neutron stars composing the binary and of their mass ratio and we have found that tori sufficiently massive to power short GRBs can indeed be formed.

  11. WhiskyMHD: Numerical Code for General Relativistic Magnetohydrodynamics

    Science.gov (United States)

    Baiotti, Luca; Giacomazzo, Bruno; Hawke, Ian; et al.

    2010-10-01

    Whisky is a code to evolve the equations of general relativistic hydrodynamics (GRHD) and magnetohydrodynamics (GRMHD) in 3D Cartesian coordinates on a curved dynamical background. It was originally developed by and for members of the EU Network on Sources of Gravitational Radiation and is based on the Cactus Computational Toolkit. Whisky can also implement adaptive mesh refinement (AMR) if compiled together with Carpet. Whisky has grown from earlier codes such as GR3D and GRAstro_Hydro, but has been rewritten to take advantage of some of the latest research performed here in the EU. The motivation behind Whisky is to compute gravitational radiation waveforms for systems that involve matter. Examples would include the merger of a binary system containing a neutron star, which are expected to be reasonably common in the universe and expected to produce substantial amounts of radiation. Other possible sources are given in the projects list.

  12. General Relativistic Effects in the Core Collapse Supernova Mechanism

    CERN Document Server

    Bruenn, S W; Mezzacappa, A

    2001-01-01

    We apply our recently developed code for spherically symmetric, fully general relativistic (GR) Lagrangian hydrodynamics and multigroup flux-limited diffusion neutrino transport to examine the effects of GR on the hydrodynamics and transport during collapse, bounce, and the critical shock reheating phase of core collapse supernovae. Comparisons of models computed with GR versus Newtonian hydrodynamics show that collapse to bounce takes slightly less time in the GR limit, and that the shock propagates slightly farther out in radius before receding. After a secondary quasistatic rise in the shock radius, the shock radius declines considerably more rapidly in the GR simulations than in the corresponding Newtonian simulations. During the shock reheating phase, core collapse computed with GR hydrodynamics results in a substantially more compact structure from the center out to the stagnated shock. The inflow speed of material behind the shock is also increased. Comparisons also show that the luminosity and rms ene...

  13. Code Development of Three-Dimensional General Relativistic Hydrodynamics with AMR(Adaptive-Mesh Refinement) and Results From Special and General Relativistic Hydrodynamic

    CERN Document Server

    Donmez, O

    2004-01-01

    In this paper, the general procedure to solve the General Relativistic Hydrodynamical(GRH) equations with Adaptive-Mesh Refinement (AMR) is presented. In order to achieve, the GRH equations are written in the conservation form to exploit their hyperbolic character. The numerical solutions of general relativistic hydrodynamic equations are done by High Resolution Shock Capturing schemes (HRSC), specifically designed to solve non-linear hyperbolic systems of conservation laws. These schemes depend on the characteristic information of the system. The Marquina fluxes with MUSCL left and right states are used to solve GRH equations. First, different test problems with uniform and AMR grids on the special relativistic hydrodynamics equations are carried out to verify the second order convergence of the code in 1D, 2D and 3D. Results from uniform and AMR grid are compared. It is found that adaptive grid does a better job when the number of resolution is increased. Second, the general relativistic hydrodynamical equa...

  14. General-equilibrium approach to energy/environmental economic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Groncki, P J

    1978-08-01

    This paper presents a brief critique of the use of fixed-coefficient input-output models for use in energy/environmental modeling systems, a shortcoming of input-output models that has been often been noted. Then, given the existence of aggregate, general-equilibrium, variable-coefficient growth models, a methodology is presented for using this information to adjust a recent disaggregated input-output table. This methodology takes into account all of the general-equilibrium aspects of the aggregate model in making the changes in the disaggregate model. The use of various weighting schemes and the implicit technological change biases they embody are examined. The methodology is being tested on historical tables for the United States, and preliminary results are discussed. This methodology's ability to fully capture the general-equilibrium nature of the economy should enhance the usefulness of input-output models in energy/environmental modeling systems.

  15. Constructing balanced equations of motion for particles in general relativistic theories: the general case

    CERN Document Server

    Gallo, Emanuel

    2016-01-01

    We present a general approach for the formulation of equations of motion for compact objects in general relativistic theories. The particle is assumed to be moving in a geometric background which in turn is asymptotically flat. By construction, the model incorporates the back reaction due to gravitational radiation generated by the motion of the particle. Our approach differs from other constructions tackling the same kind of problem.

  16. On relativistic generalization of Perelman's W-entropy and thermodynamic description of gravitational fields and cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Vacaru, Olivia [National College of Iasi (Romania); Vacaru, Sergiu I. [Quantum Gravity Research, Topanga, CA (United States); University ' ' Al.I. Cuza' ' Iasi, Project IDEI, Iasi (Romania); Werner-Heisenberg-Institute, Max-Planck-Institute for Physics, Munich (Germany); Leibniz University of Hannover, Institute for Theoretical Physics (Germany); Ruchin, Vyacheslav

    2017-03-15

    Using double 2 + 2 and 3 + 1 nonholonomic fibrations on Lorentz manifolds, we extend the concept of W-entropy for gravitational fields in general relativity (GR). Such F- and W-functionals were introduced in the Ricci flow theory of three dimensional (3-d) Riemannian metrics by Perelman (the entropy formula for the Ricci flow and its geometric applications. arXiv:math.DG/0211159). Non-relativistic 3-d Ricci flows are characterized by associated statistical thermodynamical values determined by W-entropy. Generalizations for geometric flows of 4-d pseudo-Riemannian metrics are considered for models with local thermodynamical equilibrium and separation of dissipative and non-dissipative processes in relativistic hydrodynamics. The approach is elaborated in the framework of classical field theories (relativistic continuum and hydrodynamic models) without an underlying kinetic description, which will be elaborated in other work. The 3 + 1 splitting allows us to provide a general relativistic definition of gravitational entropy in the Lyapunov-Perelman sense. It increases monotonically as structure forms in the Universe. We can formulate a thermodynamic description of exact solutions in GR depending, in general, on all spacetime coordinates. A corresponding 2 + 2 splitting with nonholonomic deformation of linear connection and frame structures is necessary for generating in very general form various classes of exact solutions of the Einstein and general relativistic geometric flow equations. Finally, we speculate on physical macrostates and microstate interpretations of the W-entropy in GR, geometric flow theories and possible connections to string theory (a second unsolved problem also contained in Perelman's work) in Polyakov's approach. (orig.)

  17. Generalized Predator-Prey Oscillations in Ecological and Economic Equilibrium

    Science.gov (United States)

    Samuelson, Paul A.

    1971-01-01

    The standard predator-prey model is generalized beyond the Volterra linear-log form. Conservative oscillations are deduced and also conversion to a variational Hamiltonian form. Generalization to more than two species is also castable into Hamiltonian form, with small vibrations around equilibrium being of undamped sinusoidal type by virtue of associated characteristic exponents all being pure imaginaries. However, introduction into ecological equilibrium of a recognition of limited space and inorganic matter destroys the autonomous periodicity of the motions and makes inapplicable the elegant formalisms of classical statistical mechanics. Introduction of simple diminishing returns leads to damped motions that are kept cyclically alive by shocks of the weather and other exogenous stochastic elements. Introduction of increasing returns solely in an interval near equilibrium leads to autonomous self-exciting oscillations near a stable limit cycle; under stochastic forcing functions, a long-run ergodic state becomes predictable. PMID:5280532

  18. HERO: A 3D General Relativistic Radiative Postprocessor for Accretion Discs around Black Holes

    CERN Document Server

    Zhu, Yucong; Sadowski, Aleksander; Psaltis, Dimitrios

    2015-01-01

    HERO (Hybrid Evaluator for Radiative Objects) is a 3D general relativistic radiative transfer code which has been tailored to the problem of analyzing radiation from simulations of relativistic accretion discs around black holes. HERO is designed to be used as a postprocessor. Given some fixed fluid structure for the disc (i.e. density and velocity as a function of position from a hydrodynamics or magnetohydrodynamics simulation), the code obtains a self-consistent solution for the radiation field and for the gas temperatures using the condition of radiative equilibrium. The novel aspect of HERO is that it combines two techniques: 1) a short characteristics (SC) solver that quickly converges to a self consistent disc temperature and radiation field, with 2) a long characteristics (LC) solver that provides a more accurate solution for the radiation near the photosphere and in the optically thin regions. By combining these two techniques, we gain both the computational speed of SC and the high accuracy of LC. W...

  19. Municipal solid waste management problems: an applied general equilibrium analysis

    NARCIS (Netherlands)

    Bartelings, H.

    2003-01-01

    Keywords: Environmental policy; General equilibrium modeling; Negishi format; Waste management policies; Market distortions.

    About 40% of the entire budget spent on environmental problems in theNetherlan

  20. An applied general equilibrium model for Dutch agribusiness policy analysis

    NARCIS (Netherlands)

    Peerlings, J.

    1993-01-01

    The purpose of this thesis was to develop a basic static applied general equilibrium (AGE) model to analyse the effects of agricultural policy changes on Dutch agribusiness. In particular the effects on inter-industry transactions, factor demand, income, and trade are of interest.

  1. Municipal solid waste management problems: an applied general equilibrium analysis

    NARCIS (Netherlands)

    Bartelings, H.

    2003-01-01

    Keywords: Environmental policy; General equilibrium modeling; Negishi format; Waste management policies; Market distortions.

    About 40% of the entire budget spent on environmental problems in the

  2. An applied general equilibrium model for Dutch agribusiness policy analysis

    NARCIS (Netherlands)

    Peerlings, J.

    1993-01-01

    The purpose of this thesis was to develop a basic static applied general equilibrium (AGE) model to analyse the effects of agricultural policy changes on Dutch agribusiness. In particular the effects on inter-industry transactions, factor demand, income, and trade are of

  3. Financial Intermediation, Competition, and Risk : A General Equilibrium Exposition

    NARCIS (Netherlands)

    Di Nicolo, G.; Lucchetta, M.

    2010-01-01

    We study a simple general equilibrium model in which investment in a risky technology is subject to moral hazard and banks can extract market power rents. We show that more bank competition results in lower economy-wide risk, lower bank capital ratios, more efficient production plans and Pareto-rank

  4. Pricing decisions in an experimental dynamic stochastic general equilibrium economy

    NARCIS (Netherlands)

    Noussair, C.N.; Pfajfar, D.; Zsiros, J.

    2015-01-01

    We construct experimental economies, populated with human subjects, with a structure based on a nonlinear version of the New Keynesian dynamic stochastic general equilibrium (DSGE) model. We analyze the behavior of firms’ pricing decisions in four different experimental economies. We consider how we

  5. An applied general equilibrium model for Dutch agribusiness policy analysis.

    NARCIS (Netherlands)

    Peerlings, J.H.M.

    1993-01-01

    The purpose of this thesis was to develop a basic static applied general equilibrium (AGE) model to analyse the effects of agricultural policy changes on Dutch agribusiness. In particular the effects on inter-industry transactions, factor demand, income, and trade are of interest.The model is fairly

  6. Pricing decisions in an experimental dynamic stochastic general equilibrium economy

    NARCIS (Netherlands)

    Noussair, C.N.; Pfajfar, D.; Zsiros, J.

    We construct experimental economies, populated with human subjects, with a structure based on a nonlinear version of the New Keynesian dynamic stochastic general equilibrium (DSGE) model. We analyze the behavior of firms’ pricing decisions in four different experimental economies. We consider how

  7. Gyrokinetic simulations with a general equilibrium distribution function

    Science.gov (United States)

    Wilkie, George; Highcock, Edmund; Abel, Ian; Dorland, William

    2013-10-01

    Applying the gyrokinetic framework to study the dynamics of fast particles requires a transport-scale equilibrium distribution that is not Maxwellian, and whose functional form may not be known a priori. The GS2 gyrokinetics code has been modified to accommodate an arbitrary equilibrium distribution and this capability has been validated. The need to resolve the tail of the distribution for fast particles introduces numerical challenges that are resolved by implementing a generalized quadrature scheme that retains spectral accuracy of velocity-space integrals. Preliminary simulation results are presented.

  8. General Equilibrium Property of Spherical Torus Configurations with Large Triangularity

    Institute of Scientific and Technical Information of China (English)

    SHIBingren

    2003-01-01

    In magnetic fusion research, two sorts of axi-symmetric toroidal equilibrium configuration are mostly interested. One is the conventional tokamak that has an aspect ratio 2. 8generally observed that equilibrium configurations with large triangular deformation usually has the merit of stabilizing higher beta plasma and better confinement scaling so that higher βN/li value can be attained. This was also verified theoretically in the ballooning mode analysis.

  9. Generalized Langevin equation description of the stochastic oscillations of general relativistic disks

    CERN Document Server

    Leung, Chun Sing; Harko, Tiberiu

    2013-01-01

    We consider a description of the stochastic oscillations of the general relativistic accretion disks around compact astrophysical objects based on the generalized Langevin equation, which accounts for the general retarded effects of the frictional force, and on the fluctuation-dissipation theorems. The vertical displacements, velocities and luminosities of the stochastically perturbed disks are explicitly obtained for both the Schwarzschild and the Kerr cases. The Power Spectral Distribution of the luminosity it is also obtained, and it is shown that it has non-standard values. The theoretical predictions of the model are compared with the observational data for the luminosity time variation of the BL Lac S5 0716+714 object.

  10. Generalized Langevin Equation Description of Stochastic Oscillations of General Relativistic Disks

    Indian Academy of Sciences (India)

    Chun Sing Leung; Gabriela Mocanu; Tiberiu Harko

    2014-09-01

    We consider a description of the stochastic oscillations of the general relativistic accretion disks around compact astrophysical objects based on the generalized Langevin equation, which accounts for the general retarded effects of the frictional force, and on the fluctuation–dissipation theorems. The vertical displacements, velocities and luminosities of the stochastically perturbed disks are explicitly obtained for both the Schwarzschild and Kerr cases. The power spectral distribution of the luminosity is also obtained, and it is shown that it has non-standard values. The theoretical predictions of the model are compared with the observational data for the luminosity time variation of the BL Lac S5 0716+714 object.

  11. General relativistic simulations of magnetized binary neutron star mergers

    CERN Document Server

    Liu, Yuk Tung; Etienne, Zachariah B; Taniguchi, Keisuke

    2008-01-01

    Binary neutron stars (NSNS) are expected to be among the leading sources of gravitational waves observable by ground-based laser interferometers and may be the progenitors of short-hard gamma ray bursts. We present a series of general relativistic NSNS coalescence simulations both for unmagnetized and magnetized stars. We adopt quasiequilibrium initial data for circular, irrotational binaries constructed in the conformal thin-sandwich (CTS) framework. We adopt the BSSN formulation for evolving the metric and a high-resolution shock-capturing scheme to handle the magnetohydrodynamics. Our simulations of unmagnetized binaries confirm the results of Shibata, Taniguchi and Uryu (2003). In cases in which the mergers result in a prompt collapse to a black hole, we are able to use puncture gauge conditions to extend the evolution and determine the mass of the material that forms a disk. We find that the disk mass is less than 2% of the total mass in all cases studied. We then add a small poloidal magnetic field to t...

  12. Relativistic Configuration Interaction Treatment of Generalized Oscillator Strength for Krypton

    Institute of Scientific and Technical Information of China (English)

    WANG Huang-Chun; QU Yi-Zhi; LIU Chun-Hua

    2007-01-01

    A fully relativistic configuration interaction method is developed to investigate the transition energies and general oscillator strengths of the lower lying states of krypton, for both optically allowed and optically forbidden transitions. The calculated results are in agreement with the recent experimental measurements. The calculated transition energies for the 5s and 5s' transitions are 9.970 and 10.717eV, which agree with the experimental data of 10.033 and 10.643 eV. The calculated oscillator strengths are 0.211 and 0.170, comparable with the experimental results 0.214(±0.012) and 0.194 (±0.012), respectively. The momentum transfer positions ( K2 in a.u.) of the minimum and maximum GOSs in the 4s24p6 → 4s24p5 (5s + 5s') transitions are 1.105 and 2.225, comparable with the measurements results 1.24 and 2.97 [Phys. Rev. A 67 (2003) 062708].

  13. General relativistic magnetohydrodynamic simulations of collapsars: Rotating black hole cases

    Energy Technology Data Exchange (ETDEWEB)

    Mizuno, Y. [Kyoto Univ., Kyoto (Japan). Department of Astronomy; Yamada, S. [Waseda Univ., Tokyo (Japan). Science and Engineering; Koide, S. [Toyama Univ., Toyama (Japan). Department of Engineering; Shibata, K. [Kyoto Univ., Kyoto (Japan). Kwasan and Hida Observatory

    2005-06-01

    We have performed 2.5-dimensional general relativistic magnetohydrodynamic (MHD) simulations of coIIapsars including a rotating black hole. InitiaIIy, we assume that the care collapse has failed in this star. A rotating black hole of a few solar masses is inserted by hand into the calculation. The simulation results show the formation of a diskIike structure and the generation of a jetIike outflow near the central black hole. The jetIike outflow propagates and accelerated mainly by the magnetic field. The total jet velocity is {approx} 0.3c. When the rotation of the black hole is faster, the magnetic field is twisted strongly owing to the frame-dragging effect. The magnetic energy stored by the twisting magnetic field is directly converted to kinetic energy of the jet rather than propagating as an Alfven wave. Thus, as the rotation of the black hole becomes faster, the poloidal velocity of the jet becomes faster.

  14. A general framework for ion equilibrium calculations in compacted bentonite

    Science.gov (United States)

    Birgersson, Martin

    2017-03-01

    An approach for treating chemical equilibrium between compacted bentonite and aqueous solutions is presented. The treatment is based on conceptualizing bentonite as a homogeneous mixture of water and montmorillonite, and assumes Gibbs-Donnan membrane equilibrium across interfaces to external solutions. An equation for calculating the electrostatic potential difference between bentonite and external solution (Donnan potential) is derived and solved analytically for some simple systems. The solutions are furthermore analyzed in order to illuminate the general mechanisms of ion equilibrium and their relation to measurable quantities. A method is suggested for estimating interlayer activity coefficients based on the notion of an interlayer ionic strength. Using this method, several applications of the framework are presented, giving a set of quantitative predictions which may be relatively simply tested experimentally, e.g.: (1) the relative amount of anions entering the bentonite depends approximately on the square-root of the external concentration for a 1:2 salt (e.g. CaCl2). For a 1:1 salt (e.g. NaCl) the dependence is approximately linear, and for a 1:2 salt (e.g. Na2SO4) the dependence is approximately quadratic. (2) Bentonite contains substantially more nitrate as compared to chloride if equilibrated with the two salt solutions at equal external concentration. (3) Potassium bentonite generally contains more anions as compared to sodium bentonite if equilibrated at the same external concentration. (4) The anion concentration ratio in two bentonite samples of different cations (but with the same density and cation exchange capacity) resembles the ion exchange selectivity coefficient for that specific cation pair. The results show that an adequate treatment of chemical equilibrium between interlayers and bulk solutions are essential when modeling compacted bentonite, and that activity corrections generally are required for relevant ion equilibrium calculations. It

  15. A Penalty Approach for Generalized Nash Equilibrium Problem

    Institute of Scientific and Technical Information of China (English)

    HOU JIAN; LAI JUN-FENG

    2012-01-01

    The generalized Nash equilibrium problem (GNEP) is a generalization of the standard Nash equilibrium problem (NEP),in which both the utility function and the strategy space of each player depend on the strategies chosen by all other players.This problem has been used to model various problems in applications.However,the convergent solution algorithms are extremely scare in the literature.In this paper,we present an incremental penalty method for the GNEP,and show that a solution of the GNEP can be found by solving a sequence of smooth NEPs.We then apply the semismooth Newton method with Armijo line search to solve latter problems and provide some results of numerical experiments to illustrate the proposed approach.

  16. The direction of migration: a dynamic general equilibrium model.

    Science.gov (United States)

    Lee, K S

    1984-11-01

    A two-sector dynamic general equilibrium model is developed "to investigate the direction of migration in response to differing demographic and consumption demand behavior, as well as variations in production conditions." The model, which involves a rural sector and an urban sector, incorporates "returns to scale and the natural rate of sectoral population growth as important determinants of the direction of migration, in addition to price and income elasticities, and the sectoral technical change rate with which...previous studies dealt."

  17. Differential topology and general equilibrium with complete and incomplete markets

    CERN Document Server

    Villanacci, Antonio; Benevieri, Pierluigi; Battinelli, Andrea

    2002-01-01

    General equilibrium In this book we try to cope with the challenging task of reviewing the so called general equilibrium model and of discussing one specific aspect of the approach underlying it, namely, market completeness. With the denomination "general equilibrium" (from now on in short GE) we shall mainly refer to two different things. On one hand, in particular when using the expression "GE approach", we shall refer to a long established methodolog­ ical tradition in building and developing economic models, which includes, as of today, an enormous amount of contributions, ranging in number by several 1 thousands • On the other hand, in particular when using the expression "stan­ dard differentiable GE model", we refer to a very specific version of economic model of exchange and production, to be presented in Chapters 8 and 9, and to be modified in Chapters 10 to 15. Such a version is certainly formulated within the GE approach, but it is generated by making several quite restrictive 2 assumptions •...

  18. General equilibrium characteristics of a dual-lift helicopter system

    Science.gov (United States)

    Cicolani, L. S.; Kanning, G.

    1986-01-01

    The equilibrium characteristics of a dual-lift helicopter system are examined. The system consists of the cargo attached by cables to the endpoints of a spreader bar which is suspended by cables below two helicopters. Results are given for the orientation angles of the suspension system and its internal forces, and for the helicopter thrust vector requirements under general circumstances, including nonidentical helicopters, any accelerating or static equilibrium reference flight condition, any system heading relative to the flight direction, and any distribution of the load to the two helicopters. Optimum tether angles which minimize the sum of the required thrust magnitudes are also determined. The analysis does not consider the attitude degrees of freedom of the load and helicopters in detail, but assumes that these bodies are stable, and that their aerodynamic forces in equilibrium flight can be determined independently as functions of the reference trajectory. The ranges of these forces for sample helicopters and loads are examined and their effects on the equilibrium characteristics are given parametrically in the results.

  19. Generalizations of the Nash Equilibrium Theorem in the KKM Theory

    Directory of Open Access Journals (Sweden)

    Park Sehie

    2010-01-01

    Full Text Available The partial KKM principle for an abstract convex space is an abstract form of the classical KKM theorem. In this paper, we derive generalized forms of the Ky Fan minimax inequality, the von Neumann-Sion minimax theorem, the von Neumann-Fan intersection theorem, the Fan-type analytic alternative, and the Nash equilibrium theorem for abstract convex spaces satisfying the partial KKM principle. These results are compared with previously known cases for -convex spaces. Consequently, our results unify and generalize most of previously known particular cases of the same nature. Finally, we add some detailed historical remarks on related topics.

  20. Generalizations of the Nash Equilibrium Theorem in the KKM Theory

    Directory of Open Access Journals (Sweden)

    Sehie Park

    2010-01-01

    Full Text Available The partial KKM principle for an abstract convex space is an abstract form of the classical KKM theorem. In this paper, we derive generalized forms of the Ky Fan minimax inequality, the von Neumann-Sion minimax theorem, the von Neumann-Fan intersection theorem, the Fan-type analytic alternative, and the Nash equilibrium theorem for abstract convex spaces satisfying the partial KKM principle. These results are compared with previously known cases for G-convex spaces. Consequently, our results unify and generalize most of previously known particular cases of the same nature. Finally, we add some detailed historical remarks on related topics.

  1. Investment Irreversibility and Precautionary Savings in General Equilibrium

    DEFF Research Database (Denmark)

    Ejarque, João

    Partial equilibrium models suggest that when uncertainty increases, agents increase savings and at the same time reduce investment in irreversible goods. This paper characterizes this problem in general equilibrium with technology shocks, additive output shocks and shocks to the marginal efficiency...... if the shocks affect the marginal efficiency of investment. For all types of shocks, when concavity of the utility function is moderate or high, the irreversibility constraint never binds and the increase in variance has a negligible impact. Persistence in the shock process induces precautionary savings rather...... than irreversibility effects. If shocks are idiosyncratic and affect a cross section of agents over capital, an increase in their variance may induce an increase in aggregate investment even if all agents have an incentive to invest less, because zero investment is now an active lower bound for part...

  2. A new iterative method for solving a system of generalized equilibrium problems, generalized mixed equilibrium problems and common fixed point problems in Hilbert spaces

    Directory of Open Access Journals (Sweden)

    Benjawan Rodjanadid

    2013-12-01

    Full Text Available In this paper, we introduce an iterative method for finding a common element of the set of solutions of a generalized mixed equilibrium problem (GMEP, the solutions of a general system of equilibrium problem and the set of common fixed points of a finite family of nonexpansive mappings in a real Hilbert space. Then, we prove that the sequence converges strongly to a common element of the above three sets. Furthermore, we apply our result to prove four new strong convergence theorems in fixed point problems, mixed equilibrium problems, generalized equilibrium problems , equilibrium problems and variational inequality.

  3. Waves in General Relativistic Two-fluid Plasma around a Schwarzschild Black Hole

    CERN Document Server

    Rahman, M Atiqur

    2010-01-01

    Waves propagating in the relativistic electron-positron or ions plasma are investigated in a frame of two-fluid equations using the 3+1 formalism of general relativity developed by Thorne, Price and Macdonald (TPM). The plasma is assumed to be freefalling in the radial direction toward the event horizon due to the strong gravitational field of a Schwarzschild black hole. The local dispersion relations for transverse and longitudinal waves have been derived, in analogy with the special relativistic formulation as explained in an earlier paper, to take account of relativistic effects due to the event horizon using WKB approximation

  4. Generalized quantum similarity in atomic systems: A quantifier of relativistic effects

    Science.gov (United States)

    Martín, A. L.; Angulo, J. C.; Antolín, J.; López-Rosa, S.

    2017-02-01

    Quantum similarity between Hartree-Fock and Dirac-Fock electron densities reveals the depth of relativistic effects on the core and valence regions in atomic systems. The results emphasize the relevance of differences in the outermost subshells, as pointed out in recent studies by means of Shannon-like functionals. In this work, a generalized similarity functional allows us to go far beyond the Shannon-based analyses. The numerical results for systems throughout the Periodic Table show that discrepancies between the relativistic and non-relativistic descriptions are patently governed by shell-filling patterns.

  5. General relativistic radiation hydrodynamics of accretion flows - II. Treating stiff source terms and exploring physical limitations

    Science.gov (United States)

    Roedig, C.; Zanotti, O.; Alic, D.

    2012-10-01

    We present the implementation of an implicit-explicit (IMEX) Runge-Kutta numerical scheme for general relativistic (GR) hydrodynamics coupled to an optically thick radiation field in two existing GR-(magneto)hydrodynamics codes. We argue that the necessity of such an improvement arises naturally in most astrophysically relevant regimes where the optical thickness is high as the equations become stiff. By performing several simple 1D tests, we verify the codes' new ability to deal with this stiffness and show consistency. Then, still in one spatial dimension, we compute a luminosity versus accretion rate diagram for the set-up of spherical accretion on to a Schwarzschild black hole and find good agreement with previous work which included more radiation processes than we currently have available. Lastly, we revisit the supersonic Bondi-Hoyle-Lyttleton (BHL) accretion in two dimensions where we can now present simulations of realistic temperatures, down to T ˜ 106 K or less. Here we find that radiation pressure plays an important role, but also that these highly dynamical set-ups push our approximate treatment towards the limit of physical applicability. The main features of radiation hydrodynamics BHL flows manifest as (i) an effective adiabatic index approaching γeff ˜ 4/3; (ii) accretion rates two orders of magnitude lower than without radiation pressure, but still super-Eddington; (iii) luminosity estimates around the Eddington limit, hence with an overall radiative efficiency as small as ηBHL˜10-2; (iv) strong departures from thermal equilibrium in shocked regions; (v) no appearance of the flip-flop instability. We conclude that the current optically thick approximation to the radiation transfer does give physically substantial improvements over the pure hydro also in set-ups departing from equilibrium, and, once accompanied by an optically thin treatment, is likely to provide a fundamental tool for investigating accretion flows in a large variety of

  6. Choreographic solution to the general-relativistic three-body problem.

    Science.gov (United States)

    Imai, Tatsunori; Chiba, Takamasa; Asada, Hideki

    2007-05-18

    We reexamine the three-body problem in the framework of general relativity. The Newtonian N-body problem admits choreographic solutions, where a solution is called choreographic if every massive particle moves periodically in a single closed orbit. One is a stable figure-eight orbit for a three-body system, which was found first by Moore (1993) and rediscovered with its existence proof by Chenciner and Montgomery (2000). In general relativity, however, the periastron shift prohibits a binary system from orbiting in a single closed curve. Therefore, it is unclear whether general-relativistic effects admit choreography such as the figure eight. We examine general-relativistic corrections to initial conditions so that an orbit for a three-body system can be choreographic and a figure eight. This illustration suggests that the general-relativistic N-body problem also may admit a certain class of choreographic solutions.

  7. Corotation resonance and overstable oscillations in black-hole accretion discs: general-relativistic calculations

    CERN Document Server

    Horak, Jiri

    2013-01-01

    We study the dynamics of spiral waves and oscillation modes in relativistic rotating discs around black holes. Generalizing the Newtonian theory, we show that wave absorption can take place at the corotation resonance, where the pattern frequency of the wave matches the background disc rotation rate. We derive the general relativistic expression for the disc vortensity (vorticity divided by surface density), which governs the behaviour of density perturbation near corotation. Depending on the gradient of the generalized disc vortensity, corotational wave absorption can lead to the amplification or damping of the spiral wave. We apply our general theory of relativistic wave dynamics to calculate the non-axisymmetric inertial-acoustic modes (also called p-modes) trapped in the inner-most region of a black hole accretion disc. Because general relativity changes the profiles of the radial epicyclic frequency and disc vortensity near the inner disc edge close to the black hole, these p-modes can become overstable ...

  8. Generalized Relativistic Wave Equations with Intrinsic Maximum Momentum

    CERN Document Server

    Ching, Chee Leong

    2013-01-01

    We examine the nonperturbative effect of maximum momentum on the relativistic wave equations. In momentum representation, we obtain the exact eigen-energies and wavefunctions of one-dimensional Klein-Gordon and Dirac equation with linear confining potentials, and the Dirac oscillator. Bound state solutions are only possible when the strength of scalar potential are stronger than vector potential. The energy spectrum of the systems studied are bounded from above, whereby classical characteristics are observed in the uncertainties of position and momentum operators. Also, there is a truncation in the maximum number of bound states that is allowed. Some of these quantum-gravitational features may have future applications.

  9. Generalized relativistic wave equations with intrinsic maximum momentum

    Science.gov (United States)

    Ching, Chee Leong; Ng, Wei Khim

    2014-05-01

    We examine the nonperturbative effect of maximum momentum on the relativistic wave equations. In momentum representation, we obtain the exact eigen-energies and wave functions of one-dimensional Klein-Gordon and Dirac equation with linear confining potentials, and the Dirac oscillator. Bound state solutions are only possible when the strength of scalar potential is stronger than vector potential. The energy spectrum of the systems studied is bounded from above, whereby classical characteristics are observed in the uncertainties of position and momentum operators. Also, there is a truncation in the maximum number of bound states that is allowed. Some of these quantum-gravitational features may have future applications.

  10. Generalized Information Equilibrium Approaches to EEG Sleep Stage Discrimination

    Directory of Open Access Journals (Sweden)

    Todd Zorick

    2016-01-01

    Full Text Available Recent advances in neuroscience have raised the hypothesis that the underlying pattern of neuronal activation which results in electroencephalography (EEG signals is via power-law distributed neuronal avalanches, while EEG signals are nonstationary. Therefore, spectral analysis of EEG may miss many properties inherent in such signals. A complete understanding of such dynamical systems requires knowledge of the underlying nonequilibrium thermodynamics. In recent work by Fielitz and Borchardt (2011, 2014, the concept of information equilibrium (IE in information transfer processes has successfully characterized many different systems far from thermodynamic equilibrium. We utilized a publicly available database of polysomnogram EEG data from fourteen subjects with eight different one-minute tracings of sleep stage 2 and waking and an overlapping set of eleven subjects with eight different one-minute tracings of sleep stage 3. We applied principles of IE to model EEG as a system that transfers (equilibrates information from the time domain to scalp-recorded voltages. We find that waking consciousness is readily distinguished from sleep stages 2 and 3 by several differences in mean information transfer constants. Principles of IE applied to EEG may therefore prove to be useful in the study of changes in brain function more generally.

  11. Generalized Information Equilibrium Approaches to EEG Sleep Stage Discrimination

    Science.gov (United States)

    Smith, Jason

    2016-01-01

    Recent advances in neuroscience have raised the hypothesis that the underlying pattern of neuronal activation which results in electroencephalography (EEG) signals is via power-law distributed neuronal avalanches, while EEG signals are nonstationary. Therefore, spectral analysis of EEG may miss many properties inherent in such signals. A complete understanding of such dynamical systems requires knowledge of the underlying nonequilibrium thermodynamics. In recent work by Fielitz and Borchardt (2011, 2014), the concept of information equilibrium (IE) in information transfer processes has successfully characterized many different systems far from thermodynamic equilibrium. We utilized a publicly available database of polysomnogram EEG data from fourteen subjects with eight different one-minute tracings of sleep stage 2 and waking and an overlapping set of eleven subjects with eight different one-minute tracings of sleep stage 3. We applied principles of IE to model EEG as a system that transfers (equilibrates) information from the time domain to scalp-recorded voltages. We find that waking consciousness is readily distinguished from sleep stages 2 and 3 by several differences in mean information transfer constants. Principles of IE applied to EEG may therefore prove to be useful in the study of changes in brain function more generally. PMID:27516806

  12. Relativistic corrections to the central force problem in a generalized potential approach

    CERN Document Server

    Singh, Ashmeet

    2014-01-01

    We present a novel technique to obtain the relativistic corrections to the central force problem in the Lagrangian formulation, using a generalized potential energy. Throughout the paper, we focus on the attractive inverse square law central force. The generalised potential can be made a part of the regular classical lagrangian which can reproduce the relativistic force equation upto second order in $|\\vec{v}|/c$. We then go on to derive the relativistically corrected Hamiltonian from the Lagrangian and estimate the corrections to the total energy of the system. We employ our methodology to calculate the relativistic correction to the circular orbit in attractive gravitational force. We also estimate to the first order energy correction in the ground state of the hydrogen atom in the semi-classical approach. Our predictions in both problems give the reasonable agreement with the known results. Thus we feel that this work has pedagogical value and can be used by undergraduate students to better understand the ...

  13. A NEW CLASS OF BILEVEL GENERALIZED MIXED EQUILIBRIUM PROBLEMS IN BANACH SPACES

    Institute of Scientific and Technical Information of China (English)

    Ding Xieping

    2012-01-01

    A new class of bilevel generalized mixed equilibrium problems involving setvalued mappings is introduced and studied in a real Banach space.By using the auxiliary principle technique,new iterative algorithms for solving the generalized mixed equilibrium problems and bilevel generalized mixed equilibrium problems involving set-valued mappings are suggested and analyzed.Existence of solutions and strong convergence of the iterative sequences generated by the algorithms are proved under quite mild conditions.The behavior of the solution set of the generalized mixed equilibrium problems and bilevel generalized mixed equilibrium problems is also discussed.These results are new and generalize some recent results in this field.

  14. Exploring Chemical Equilibrium with Poker Chips: A General Chemistry Laboratory Exercise

    Science.gov (United States)

    Bindel, Thomas H.

    2012-01-01

    A hands-on laboratory exercise at the general chemistry level introduces students to chemical equilibrium through a simulation that uses poker chips and rate equations. More specifically, the exercise allows students to explore reaction tables, dynamic chemical equilibrium, equilibrium constant expressions, and the equilibrium constant based on…

  15. Exploring Chemical Equilibrium with Poker Chips: A General Chemistry Laboratory Exercise

    Science.gov (United States)

    Bindel, Thomas H.

    2012-01-01

    A hands-on laboratory exercise at the general chemistry level introduces students to chemical equilibrium through a simulation that uses poker chips and rate equations. More specifically, the exercise allows students to explore reaction tables, dynamic chemical equilibrium, equilibrium constant expressions, and the equilibrium constant based on…

  16. Heat flux in the presence of a gravitational field in a simple dilute fluid: an approach based in general relativistic kinetic theory to first order in the gradients

    CERN Document Server

    Brun-Battistini, D; Sandoval-Villalbazo, A

    2016-01-01

    Richard C. Tolman analyzed the relation between a temperature gradient and a gravitational field in an equilibrium situation. In 2012, Tolman\\textquoteright s law was generalized to a non-equilibrium situation for a simple dilute relativistic fluid. The result in that scenario, obtained by introducing the gravitational force through the molecular acceleration, couples the heat flux with the metric coefficients and the gradients of the state variables. In the present paper it is shown, by \\textquotedblleft suppressing\\textquotedblright{} the molecular acceleration in Boltzmann\\textquoteright s equation, that a gravitational field drives a heat flux. This procedure corresponds to the description of particle motion through geodesics, in which a Newtonian limit to the Schwarzschild metric is assumed. The effect vanishes in the non-relativistic regime, as evidenced by the direct evaluation of the corresponding limit.

  17. Comment on "General equilibrium shape equations of polymer chains".

    Science.gov (United States)

    Thamwattana, Ngamta; Hill, James M

    2008-07-01

    In this Comment, we point out that the Euler-Lagrange equations, which are referred to as the general equilibrium shape equations presented by Zhang et al. [Phys. Rev. E 70, 051902 (2004)] are incorrect, along with equations derived from them. The correct equations are provided here and they are cross-checked using certain energy functions previously presented in the literature. Further, with the use of the correct equations, we present new numerical results, which for the values of the constants given by Zhang et al. do not give rise to the physical behavior observed for DNA by those authors. However, the correct equations can be consistent with sensible behavior for different values of the constants.

  18. Financial Structure and Economic Welfare: Applied General Equilibrium Development Economics.

    Science.gov (United States)

    Townsend, Robert

    2010-09-01

    This review provides a common framework for researchers thinking about the next generation of micro-founded macro models of growth, inequality, and financial deepening, as well as direction for policy makers targeting microfinance programs to alleviate poverty. Topics include treatment of financial structure general equilibrium models: testing for as-if-complete markets or other financial underpinnings; examining dual-sector models with both a perfectly intermediated sector and a sector in financial autarky, as well as a second generation of these models that embeds information problems and other obstacles to trade; designing surveys to capture measures of income, investment/savings, and flow of funds; and aggregating individuals and households to the level of network, village, or national economy. The review concludes with new directions that overcome conceptual and computational limitations.

  19. General equilibrium effects of increasing carbon taxes in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, G.W. [South Carolina Univ., Columbia, SC (United States). Dept. of Economics, College of Business Administration; Kristroem, B. [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Forest Economics

    1997-09-01

    Sweden was one of the first countries to introduce carbon taxes, and is currently evaluating further carbon taxes. The authors were asked to advise a government commission charged with undertaking the official Swedish evaluation. We did so by constructing and simulating a computable general equilibrium model of Sweden. In this report, the carbon tax debate in Sweden is first reviewed, then our model is described and the main results presented. The conclusion from the cost-benefit analysis is clear, the benefits of increasing the carbon tax in Sweden are a tiny fraction of the costs that consumers must pay in the form of higher prices and reduced incomes. Although we do not put much credence in the gross benefit numbers, they do serve to highlight the basis of our conclusion that carbon tax increases are not currently justifiable in Sweden. 35 refs., 13 tabs.

  20. Financial Structure and Economic Welfare: Applied General Equilibrium Development Economics

    Science.gov (United States)

    Townsend, Robert

    2010-01-01

    This review provides a common framework for researchers thinking about the next generation of micro-founded macro models of growth, inequality, and financial deepening, as well as direction for policy makers targeting microfinance programs to alleviate poverty. Topics include treatment of financial structure general equilibrium models: testing for as-if-complete markets or other financial underpinnings; examining dual-sector models with both a perfectly intermediated sector and a sector in financial autarky, as well as a second generation of these models that embeds information problems and other obstacles to trade; designing surveys to capture measures of income, investment/savings, and flow of funds; and aggregating individuals and households to the level of network, village, or national economy. The review concludes with new directions that overcome conceptual and computational limitations. PMID:21037939

  1. The dynamics of general relativistic isotropic stellar cluster models -- Do relativistic extensions of the Plummer model exist?

    CERN Document Server

    De Rijcke, Sven; Boelens, Thomas

    2014-01-01

    We show that the general relativistic theory of the dynamics of isotropic stellar clusters can be developed essentially along the same lines as the Newtonian theory. We prove that the distribution function can be derived from any isotropic momentum moment and that every higher-order moment of the distribution can be written as an integral over a zeroth-order moment. We propose a mathematically simple expression for the distribution function of a family of isotropic general relativistic cluster models and investigate their dynamical properties. In the Newtonian limit, these models obtain a distribution function of the form F(E) ~ (E-E_0)^alpha, with E binding energy and E_0 a constant that determines the model's outer radius. The slope alpha sets the steepness of the distribution function and the corresponding radial density and pressure profiles. We show that the field equations only yield solutions with finite mass for alpha3.5, only Newtonian models exist. In other words: within the context of this family o...

  2. General relativistic polytropes with a repulsive cosmological constant

    CERN Document Server

    Stuchlík, Zdeněk; Novotný, Jan

    2016-01-01

    Spherically symmetric equilibrium configurations of perfect fluid obeying a polytropic equation of state are studied in spacetimes with a repulsive cosmological constant. The configurations are specified in terms of three parameters---the polytropic index $n$, the ratio of central pressure and central energy density of matter $\\sigma$, and the ratio of energy density of vacuum and central density of matter $\\lambda$. The static equilibrium configurations are determined by two coupled first-order nonlinear differential equations that are solved by numerical methods with the exception of polytropes with $n=0$ corresponding to the configurations with a uniform distribution of energy density, when the solution is given in terms of elementary functions. The geometry of the polytropes is conveniently represented by embedding diagrams of both the ordinary space geometry and the optical reference geometry reflecting some dynamical properties of the geodesic motion. The polytropes are represented by radial profiles of...

  3. General-Relativistic Resistive Magnetohydrodynamics in three dimensions: formulation and tests

    CERN Document Server

    Dionysopoulou, Kyriaki; Palenzuela, Carlos; Rezzolla, Luciano; Giacomazzo, Bruno

    2013-01-01

    We present a new numerical implementation of the general-relativistic resistive magnetohydrodynamics (MHD) equations within the Whisky code. The numerical method adopted exploits the properties of Implicit-Explicit Runge-Kutta numerical schemes to treat the stiff terms that appear in the equations for small electrical conductivities. Using tests in one, two, and three dimensions, we show that our implementation is robust and recovers the ideal-MHD limit in regimes of very high conductivity. Moreover, the results illustrate that the code is capable of describing physical setups in all ranges of conductivities. In addition to tests in flat spacetime, we report simulations of magnetized nonrotating relativistic stars, both in the Cowling approximation and in dynamical spacetimes. Finally, because of its astrophysical relevance and because it provides a severe testbed for general-relativistic codes with dynamical electromagnetic fields, we study the collapse of a nonrotating star to a black hole. We show that als...

  4. Teaching Chemical Equilibrium and Thermodynamics in Undergraduate General Chemistry Classes.

    Science.gov (United States)

    Banerjee, Anil C.

    1995-01-01

    Discusses some of the conceptual difficulties encountered by undergraduate students in learning certain aspects of chemical equilibrium and thermodynamics. Discusses teaching strategies for dealing with these difficulties. (JRH)

  5. Local equilibrium solutions in simple anisotropic cosmological models, as described by relativistic fluid dynamics

    CERN Document Server

    Shogin, Dmitry

    2015-01-01

    We test the physical relevance of the full and truncated versions of the Israel-Stewart theory of irreversible thermodynamics in a cosmological setting. Using a dynamical systems method, we determine the asymptotic future of plane symmetric Bianchi type I spacetimes filled with a viscous {\\gamma}-fluid, keeping track of the magnitude of relative dissipative fluxes, which determines the applicability of the Israel-Stewart theory. We consider the situations when the dissipative mechanisms of shear and bulk viscosity are involved separately and simultaneously. Also, we apply two different temperature models in the full version of the theory in order to compare the results. We demonstrate that the only case when the fluid asymptotically approaches local equilibrium, and the underlying assumptions of the IS theory are therefore not violated, is that of a dissipative fluid with vanishing bulk viscosity. The truncated Israel-Stewart equations for shear viscosity are found to produce solutions which manifest patholog...

  6. Computable general equilibrium model fiscal year 2013 capability development report

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Brian Keith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rivera, Michael Kelly [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Boero, Riccardo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-17

    This report documents progress made on continued developments of the National Infrastructure Simulation and Analysis Center (NISAC) Computable General Equilibrium Model (NCGEM), developed in fiscal year 2012. In fiscal year 2013, NISAC the treatment of the labor market and tests performed with the model to examine the properties of the solutions computed by the model. To examine these, developers conducted a series of 20 simulations for 20 U.S. States. Each of these simulations compared an economic baseline simulation with an alternative simulation that assumed a 20-percent reduction in overall factor productivity in the manufacturing industries of each State. Differences in the simulation results between the baseline and alternative simulations capture the economic impact of the reduction in factor productivity. While not every State is affected in precisely the same way, the reduction in manufacturing industry productivity negatively affects the manufacturing industries in each State to an extent proportional to the reduction in overall factor productivity. Moreover, overall economic activity decreases when manufacturing sector productivity is reduced. Developers ran two additional simulations: (1) a version of the model for the State of Michigan, with manufacturing divided into two sub-industries (automobile and other vehicle manufacturing as one sub-industry and the rest of manufacturing as the other subindustry); and (2) a version of the model for the United States, divided into 30 industries. NISAC conducted these simulations to illustrate the flexibility of industry definitions in NCGEM and to examine the simulation properties of in more detail.

  7. Perturbation to Lie Symmetry and Generalized Hojman Adiabatic Invariants for Relativistic Hamilton System

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-Sheng; ZHANG Xiao-Ni; YUAN Bao-He; FANG Jian-Hui; YANG Guo-Hong; LIN Peng; PANG Ting

    2008-01-01

    Based on the concept of higher-order adiabatic invariants of mechanical system with action of a small perturbation, the perturbation to Lie symmetry and generalized Hojman adiabatic invariants for the relativistic Hamilton system are studied. Perturbation to Lie symmetry is discussed under general infinitesimal transformation of groups in which time is variable. The form and the criterion of generalized Hojman adiabatic invariants for this system are obtained. Finally, an example is given to illustrate the results.

  8. Local equilibrium solutions in simple anisotropic cosmological models, as described by relativistic fluid dynamics

    Science.gov (United States)

    Shogin, Dmitry; Amund Amundsen, Per

    2016-10-01

    We test the physical relevance of the full and the truncated versions of the Israel–Stewart (IS) theory of irreversible thermodynamics in a cosmological setting. Using a dynamical systems method, we determine the asymptotic future of plane symmetric Bianchi type I spacetimes with a viscous mathematical fluid, keeping track of the magnitude of the relative dissipative fluxes, which determines the applicability of the IS theory. We consider the situations where the dissipative mechanisms of shear and bulk viscosity are involved separately and simultaneously. It is demonstrated that the only case in the given model when the fluid asymptotically approaches local thermal equilibrium, and the underlying assumptions of the IS theory are therefore not violated, is that of a dissipative fluid with vanishing bulk viscosity. The truncated IS equations for shear viscosity are found to produce solutions which manifest pathological dynamical features and, in addition, to be strongly sensitive to the choice of initial conditions. Since these features are observed already in the case of an oversimplified mathematical fluid model, we have no reason to assume that the truncation of the IS transport equations will produce relevant results for physically more realistic fluids. The possible role of bulk and shear viscosity in cosmological evolution is also discussed.

  9. Numerical solutions of general-relativistic field equations for rapidly rotating neutron stars

    Institute of Scientific and Technical Information of China (English)

    吴雪君; 须重明

    1997-01-01

    Stationary axial symmetric equilibrium configurations rapidly rotating with uniform angular velocity in the framework of genera! relativity are considered. Sequences of models are numerically computed by means of a computer code that solves the full Einstein equations exactly. This code employs Neugebauer’s minimal surface formalism, where the field equations are equivalent to two-dimensional minimal surface equations for 4 metric potentials. The calculations are based upon 10 different equations of state. Results of various structures of neutron stars and the rotational effects on stellar structures and properties are reported. Finally some limits to equations of state of neutron stars and the stability for rapidly rotating relativistic neutron stars are discussed.

  10. Post-relativistic gravity a hidden variable theory for general relativity

    CERN Document Server

    Schmelzer, I

    1996-01-01

    Post-relativistic gravity is a hidden variable theory for general relativity. It introduces the pre-relativistic notions absolute space, absolute time, and ether as hidden variables into general relativity. Evolution is defined by the equations of general relativity and the harmonic coordinate condition interpreted as a physical equation. There are minor differences in predictions compared with general relativity (i.e. trivial topology of the universe is predicted). The unobservable absolute time is designed to solve the problem of time in quantization of general relativity. Background space and time define a Newtonian frame for the quantization of the gravitational field. By the way, a lot of other conceptual problems of quantization will be solved (i.e. no constraints, no topological foam, no black hole and bib bang singularities, natural vacuum definition for quantum fields on classical background).

  11. GRHydro: A new open source general-relativistic magnetohydrodynamics code for the Einstein Toolkit

    CERN Document Server

    Moesta, Philipp; Faber, Joshua A; Haas, Roland; Noble, Scott C; Bode, Tanja; Loeffler, Frank; Ott, Christian D; Reisswig, Christian; Schnetter, Erik

    2013-01-01

    We present the new general-relativistic magnetohydrodynamics (GRMHD) capabilities of the Einstein Toolkit, an open-source community-driven numerical relativity and computational relativistic astrophysics code. The GRMHD extension of the Toolkit builds upon previous releases and implements the evolution of relativistic magnetised fluids in the ideal MHD limit in fully dynamical spacetimes using the same shock-capturing techniques previously applied to hydrodynamical evolution. In order to maintain the divergence-free character of the magnetic field, the code implements both hyperbolic divergence cleaning and constrained transport schemes. We present test results for a number of MHD tests in Minkowski and curved spacetimes. Minkowski tests include aligned and oblique planar shocks, cylindrical explosions, magnetic rotors, Alfv\\'en waves and advected loops, as well as a set of tests designed to study the response of the divergence cleaning scheme to numerically generated monopoles. We study the code's performanc...

  12. Whistler-Mode Waves Growth by a Generalized Relativistic Kappa-Type Distribution

    Institute of Scientific and Technical Information of China (English)

    ZHOU Qing-Hua; JIANG Bin; SHI Xiang-Hua; LI Jun-Qiu

    2009-01-01

    The instability of field-aligned Whistler-mode waves in space plasmas is studied by using a recently developed generalized relativistic kappa-type (KT) distribution. Numerical calculations are performed for a direct compar-ison between the new KT distribution and the current kappa distribution. We show that the wave growth for the KT distribution tends to occur in the lower wave frequency (e.g., ω 0.1Ωe) due to a larger fractional num-ber of the resonant electrons ηrel (which controls the wave growth), while primarily locating in the higher wave frequency for the kappa distribution. Moreover, the relativistic anisotropy Arel by the KT distribution is found to be smaller than that by the kappa distribution, leading to a smaller peak of wave growth. The results present a further understanding of plasma wave instability particularly in those plasmas where relativistic electrons are present.

  13. WHAM: A WENO-based general relativistic numerical scheme I: Hydrodynamics

    CERN Document Server

    Tchekhovskoy, Alexander; Narayan, Ramesh

    2007-01-01

    Active galactic nuclei, x-ray binaries, pulsars, and gamma-ray bursts are all believed to be powered by compact objects surrounded by relativistic plasma flows driving phenomena such as accretion, winds, and jets. These flows are often accurately modelled by the relativistic magnetohydrodynamics (MHD) approximation. Time-dependent numerical MHD simulations have proven to be especially insightful, but one regime that remains difficult to simulate is when the energy scales (kinetic, thermal, magnetic) within the plasma become disparate. We develop a numerical scheme that significantly improves the accuracy and robustness of the solution in this regime. We use a modified form of the WENO method to construct a finite-volume general relativistic hydrodynamics code called WHAM that converges at fifth order. We avoid (1) field-by-field decomposition by adaptively reducing down to 2-point stencils near discontinuities for a more accurate treatment of shocks, and (2) excessive reduction to low order stencils, as in th...

  14. General relativistic hydrodynamics with Adaptive-Mesh Refinement (AMR) and modeling of accretion disks

    Science.gov (United States)

    Donmez, Orhan

    We present a general procedure to solve the General Relativistic Hydrodynamical (GRH) equations with Adaptive-Mesh Refinement (AMR) and model of an accretion disk around a black hole. To do this, the GRH equations are written in a conservative form to exploit their hyperbolic character. The numerical solutions of the general relativistic hydrodynamic equations is done by High Resolution Shock Capturing schemes (HRSC), specifically designed to solve non-linear hyperbolic systems of conservation laws. These schemes depend on the characteristic information of the system. We use Marquina fluxes with MUSCL left and right states to solve GRH equations. First, we carry out different test problems with uniform and AMR grids on the special relativistic hydrodynamics equations to verify the second order convergence of the code in 1D, 2 D and 3D. Second, we solve the GRH equations and use the general relativistic test problems to compare the numerical solutions with analytic ones. In order to this, we couple the flux part of general relativistic hydrodynamic equation with a source part using Strang splitting. The coupling of the GRH equations is carried out in a treatment which gives second order accurate solutions in space and time. The test problems examined include shock tubes, geodesic flows, and circular motion of particle around the black hole. Finally, we apply this code to the accretion disk problems around the black hole using the Schwarzschild metric at the background of the computational domain. We find spiral shocks on the accretion disk. They are observationally expected results. We also examine the star-disk interaction near a massive black hole. We find that when stars are grounded down or a hole is punched on the accretion disk, they create shock waves which destroy the accretion disk.

  15. The generalized Coulomb interactions for relativistic scalar bosons

    Science.gov (United States)

    Zarrinkamar, S.; Panahi, H.; Rezaei, M.

    2016-07-01

    Approximate analytical solutions of Duffin-Kemmer-Petiau (DKP) equation are obtained for the truncated Coulomb, generalized Cornell, Richardson and Song-Lin potentials via the quasi-exact analytical ansatz approach.

  16. Computable General Equilibrium Techniques for Carbon Tax Modeling

    Directory of Open Access Journals (Sweden)

    Al-Amin

    2009-01-01

    Full Text Available Problem statement: Lacking of proper environmental models environmental pollution is now a solemn problem in many developing countries particularly in Malaysia. Some empirical studies of worldwide reveal that imposition of a carbon tax significantly decreases carbon emissions and does not dramatically reduce economic growth. To our knowledge there has not been any research done to simulate the economic impact of emission control policies in Malaysia. Approach: Therefore this study developed an environmental computable general equilibrium model for Malaysia and investigated carbon tax policy responses in the economy applying exogenously different degrees of carbon tax into the model. Three simulations were carried out using a Malaysian social accounting matrix. Results: The carbon tax policy illustrated that a 1.21% reduction of carbon emission reduced the nominal GDP by 0.82% and exports by 2.08%; 2.34% reduction of carbon emission reduced the nominal GDP by 1.90% and exports by 3.97% and 3.40% reduction of carbon emission reduced the nominal GDP by 3.17% and exports by 5.71%. Conclusion/Recommendations: Imposition of successively higher carbon tax results in increased government revenue from baseline by 26.67, 53.07 and 79.28% respectively. However, fixed capital investment increased in scenario 1a by 0.43% and decreased in scenarios 1b and 1c by 0.26 and 1.79% respectively from the baseline. According to our policy findings policy makers should consider 1st (scenario 1a carbon tax policy. This policy results in achieving reasonably good environmental impacts without losing the investment, fixed capital investment, investment share of nominal GDP and government revenue.

  17. SYSTEM OF GENERALIZED VECTOR QUASI-EQUILIBRIUM PROBLEMS ON PRODUCT FC-SPACES

    Institute of Scientific and Technical Information of China (English)

    Ding Xieping

    2007-01-01

    By applying a maximal element theorem on product FC-space due to author, some new equilibrium existence theorems for generalized games with fuzzy constraint correspondences are proved in FC-spaces. By using these equilibrium existence theorems, some new existence theorems of solutions for the system of generalized vector quasi-equilibrium problems are established in noncompact product FC-spaces. These results improve and generalize some recent results in literature to product FC-spaces without any convexity structure.

  18. Size dependence of the relaxation rate for non-equilibrium redistributions of the magnetization in Ni–Fe heterestuctures: Exchange vs. relativistic damping scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Yastremsky, I.A., E-mail: yastremsky@ukr.net

    2015-05-15

    The relaxation of non-equilibrium redistributions of the magnetization in a model Ni–Fe heterostructure is analyzed on the basis of the Landau–Lifshitz equation with the relaxation terms proposed by Bar'yakhtar. Bar'yakhtar‘s terms account for both the relativistic (local) and exchange (nonlocal) relaxations. It is demonstrated that the role of the nonlocal relaxation term (a spin current flowing between layers) increases for smaller systems. For nanometer-size systems the nonlocal relaxation term significantly enhances the relaxation of the Ni layer magnetization back to equilibrium. The reason of this size dependence is a competition of fast magnetization dynamics, induced by the nonlocal relaxation term near an interface between metals and slow, relativistic dynamics, which occurs at each point of the Ni–Fe heterostructure. This study provides insight in how to achieve an exceptionally fast remagnetization in magnetic heterostructures after laser excitation. - Highlights: • The relaxation of non-equilibrium spin states in a Ni–Fe heterostructure is analyzed. • Both the exchange (nonlocal) and relativistic (local) relaxations are accounted. • The nonlocal relaxation is concurrent with the creation of a spin current. • The role of the spin current increases for thinner metallic layers. • For nanometer-size systems the relaxation is primarily driven by the spin current.

  19. Generalized Levitin-Polyak Well-Posedness of Vector Equilibrium Problems

    OpenAIRE

    Zhao Lai-Jun; Peng Jian-Wen; Wang Yan

    2009-01-01

    Abstract We study generalized Levitin-Polyak well-posedness of vector equilibrium problems with functional constraints as well as an abstract set constraint. We will introduce several types of generalized Levitin-Polyak well-posedness of vector equilibrium problems and give various criteria and characterizations for these types of generalized Levitin-Polyak well-posedness.

  20. Generalized Levitin-Polyak Well-Posedness of Vector Equilibrium Problems

    Directory of Open Access Journals (Sweden)

    Zhao Lai-Jun

    2009-01-01

    Full Text Available Abstract We study generalized Levitin-Polyak well-posedness of vector equilibrium problems with functional constraints as well as an abstract set constraint. We will introduce several types of generalized Levitin-Polyak well-posedness of vector equilibrium problems and give various criteria and characterizations for these types of generalized Levitin-Polyak well-posedness.

  1. Generalized Levitin-Polyak Well-Posedness of Vector Equilibrium Problems

    Directory of Open Access Journals (Sweden)

    Lai-Jun Zhao

    2009-01-01

    Full Text Available We study generalized Levitin-Polyak well-posedness of vector equilibrium problems with functional constraints as well as an abstract set constraint. We will introduce several types of generalized Levitin-Polyak well-posedness of vector equilibrium problems and give various criteria and characterizations for these types of generalized Levitin-Polyak well-posedness.

  2. General relativistic effects in quantum interference of "clocks"

    CERN Document Server

    Zych, Magdalena; Costa, Fabio; Brukner, Časlav

    2016-01-01

    Quantum mechanics and general relativity have been each successfully tested in numerous experiments. However, the regime where both theories are jointly required to explain physical phenomena remains untested by laboratory experiments, and is also not fully understood by theory. This contribution reviews recent ideas for a new type of experiments: quantum interference of "clocks", which aim to test novel quantum effects that arise from time dilation. "Clock" interference experiments could be realised with atoms or photons in near future laboratory experiments.

  3. RAISHIN: A High-Resolution Three-Dimensional General Relativistic Magnetohydrodynamics Code

    Science.gov (United States)

    Mizuno, Yosuke; Nishikawa, Ken-Ichi; Koide, Shinji; Hardee, Philip; Fishman, Gerald J.

    2006-01-01

    We have developed a new three-dimensional general relativistic magnetohydrodynamic (GRMHD) code, RAISHIN, using a conservative, high resolution shock-capturing scheme. The numerical fluxes are calculated using the Harten, Lax, & van Leer (HLL) approximate Riemann solver scheme. The flux-interpolated, constrained transport scheme is used to maintain a divergence-free magnetic field. In order to examine the numerical accuracy and the numerical efficiency, the code uses four different reconstruction methods: piecewise linear methods with Minmod and MC slope-limiter function, convex essentially non-oscillatory (CENO) method, and piecewise parabolic method (PPM) using multistep TVD Runge-Kutta time advance methods with second and third-order time accuracy. We describe code performance on an extensive set of test problems in both special and general relativity. Our new GRMHD code has proven to be accurate in second order and has successfully passed with all tests performed, including highly relativistic and magnetized cases in both special and general relativity.

  4. General relativistic effects in quantum interference of “clocks”

    Science.gov (United States)

    Zych, M.; Pikovski, I.; Costa, F.; Brukner, Č.

    2016-06-01

    Quantum mechanics and general relativity have been each successfully tested in numerous experiments. However, the regime where both theories are jointly required to explain physical phenomena remains untested by laboratory experiments, and is also not fully understood by theory. This contribution reviews recent ideas for a new type of experiments: quantum interference of “clocks”, which aim to test novel quantum effects that arise from time dilation. “Clock” interference experiments could be realised with atoms or photons in near future laboratory experiments.

  5. A choreographic solution to the general relativistic three-body problem

    CERN Document Server

    Imai, T; Chiba, T; Asada, Hideki; Chiba, Takamasa; Imai, Tatsunori

    2007-01-01

    We revisit the three-body problem in the framework of general relativity. The Newtonian N-body problem admits choreographic solutions, where a solution is called choreographic if every massive particles move periodically in a single closed orbit. One is a stable figure-eight orbit of a three-body system, which was found first by Moore (1993) and re-discovered with its existence proof by Chenciner and Montgomery (2000), In general relativity, however, the periastron shift prohibits a binary system from orbiting in a closed curve. Therefore, it is unclear whether general relativistic effects admit a choreographic solution such as the figure-eight. We carefully examine general relativistic corrections to initial conditions so that an orbit to a three-body system can be closed in a figure-eight. This solution is still choreographic without causing periastron shift. This illustration suggests that the general relativistic N-body problem also may admit a certain class of choreographic solutions.

  6. Code Development of Three-Dimensional General Relativistic Hydrodynamics with AMR (Adaptive-Mesh Refinement) and Results from Special and General Relativistic Hydrodynamics

    Science.gov (United States)

    Dönmez, Orhan

    2004-09-01

    In this paper, the general procedure to solve the general relativistic hydrodynamical (GRH) equations with adaptive-mesh refinement (AMR) is presented. In order to achieve, the GRH equations are written in the conservation form to exploit their hyperbolic character. The numerical solutions of GRH equations are obtained by high resolution shock Capturing schemes (HRSC), specifically designed to solve nonlinear hyperbolic systems of conservation laws. These schemes depend on the characteristic information of the system. The Marquina fluxes with MUSCL left and right states are used to solve GRH equations. First, different test problems with uniform and AMR grids on the special relativistic hydrodynamics equations are carried out to verify the second-order convergence of the code in one, two and three dimensions. Results from uniform and AMR grid are compared. It is found that adaptive grid does a better job when the number of resolution is increased. Second, the GRH equations are tested using two different test problems which are Geodesic flow and Circular motion of particle In order to do this, the flux part of GRH equations is coupled with source part using Strang splitting. The coupling of the GRH equations is carried out in a treatment which gives second order accurate solutions in space and time.

  7. GENERALIZED VECTOR QUASI-EQUILIBRIUM PROBLEMS IN LOCALLY G-CONVEX SPACES

    Institute of Scientific and Technical Information of China (English)

    DING Xie-ping

    2005-01-01

    Some classes of generalized vector quasi-equilibrium problems (in short,GVQEP) are introduced and studied in locally G-convex spaces which includes most of generalized vector equilibrium problems, generalized vector variational inequality problems,quasi-equilibrium problems and quasi-variational inequality problems as special cases. First,an equilibrium existence theorem for one person games is proved in locally G-convex spaces.As applications, some new existence theorems of solutions for the GVQEP are established in noncompact locally G-convex spaces. These results and argument methods are new and completely different from that in recent literature.

  8. General Relativistic Non-radial Oscillations of Compact Stars

    Science.gov (United States)

    Hall, Zack, II; Jaikumar, Prashanth

    2017-01-01

    Currently, we lack a means of identifying the type of matter at the core of compact stars, but in the future, we may be able to use gravitational wave signals produced by fluid oscillations inside compact stars to discover new phases of dense matter. To this end, we study the fluid perturbations inside compact stars such as Neutron Stars and Strange Quark Stars, focusing on modes that couple to gravitational waves. Using a modern equation of state for quark matter that incorporates interactions at moderately high densities, we implement an efficient computational scheme to solve the oscillation equations in the framework of General Relativity, and determine the complex eigenfrequencies that describe the oscillation and damping of the non-radial fluid modes. We discuss the significance of our results for future detection of these modes through gravitational waves. This work is supported in part by the CSULB Graduate Research Fellowship and by the National Science Foundation NSF PHY-1608959.

  9. Relativistic viscoelastic fluid mechanics.

    Science.gov (United States)

    Fukuma, Masafumi; Sakatani, Yuho

    2011-08-01

    A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski space-time become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

  10. Response Theory for Equilibrium and Non-Equilibrium Statistical Mechanics: Causality and Generalized Kramers-Kronig Relations

    Science.gov (United States)

    Lucarini, Valerio

    2008-05-01

    We consider the general response theory recently proposed by Ruelle for describing the impact of small perturbations to the non-equilibrium steady states resulting from Axiom A dynamical systems. We show that the causality of the response functions entails the possibility of writing a set of Kramers-Kronig (K-K) relations for the corresponding susceptibilities at all orders of nonlinearity. Nonetheless, only a special class of directly observable susceptibilities obey K-K relations. Specific results are provided for the case of arbitrary order harmonic response, which allows for a very comprehensive K-K analysis and the establishment of sum rules connecting the asymptotic behavior of the harmonic generation susceptibility to the short-time response of the perturbed system. These results set in a more general theoretical framework previous findings obtained for optical systems and simple mechanical models, and shed light on the very general impact of considering the principle of causality for testing self-consistency: the described dispersion relations constitute unavoidable benchmarks that any experimental and model generated dataset must obey. The theory exposed in the present paper is dual to the time-dependent theory of perturbations to equilibrium states and to non-equilibrium steady states, and has in principle similar range of applicability and limitations. In order to connect the equilibrium and the non equilibrium steady state case, we show how to rewrite the classical response theory by Kubo so that response functions formally identical to those proposed by Ruelle, apart from the measure involved in the phase space integration, are obtained. These results, taking into account the chaotic hypothesis by Gallavotti and Cohen, might be relevant in several fields, including climate research. In particular, whereas the fluctuation-dissipation theorem does not work for non-equilibrium systems, because of the non-equivalence between internal and external

  11. Quantum interferometric visibility as a witness of general relativistic proper time.

    Science.gov (United States)

    Zych, Magdalena; Costa, Fabio; Pikovski, Igor; Brukner, Časlav

    2011-10-18

    Current attempts to probe general relativistic effects in quantum mechanics focus on precision measurements of phase shifts in matter-wave interferometry. Yet, phase shifts can always be explained as arising because of an Aharonov-Bohm effect, where a particle in a flat space-time is subject to an effective potential. Here we propose a quantum effect that cannot be explained without the general relativistic notion of proper time. We consider interference of a 'clock'-a particle with evolving internal degrees of freedom-that will not only display a phase shift, but also reduce the visibility of the interference pattern. According to general relativity, proper time flows at different rates in different regions of space-time. Therefore, because of quantum complementarity, the visibility will drop to the extent to which the path information becomes available from reading out the proper time from the 'clock'. Such a gravitationally induced decoherence would provide the first test of the genuine general relativistic notion of proper time in quantum mechanics.

  12. Critical rotation of general-relativistic polytropic models revisited

    Science.gov (United States)

    Geroyannis, V.; Karageorgopoulos, V.

    2013-09-01

    We develop a perturbation method for computing the critical rotational parameter as a function of the equatorial radius of a rigidly rotating polytropic model in the "post-Newtonia approximation" (PNA). We treat our models as "initial value problems" (IVP) of ordinary differential equations in the complex plane. The computations are carried out by the code dcrkf54.f95 (Geroyannis and Valvi 2012 [P1]; modified Runge-Kutta-Fehlberg code of fourth and fifth order for solving initial value problems in the complex plane). Such a complex-plane treatment removes the syndromes appearing in this particular family of IVPs (see e.g. P1, Sec. 3) and allows continuation of the numerical integrations beyond the surface of the star. Thus all the required values of the Lane-Emden function(s) in the post-Newtonian approximation are calculated by interpolation (so avoiding any extrapolation). An interesting point is that, in our computations, we take into account the complete correction due to the gravitational term, and this issue is a remarkable difference compared to the classical PNA. We solve the generalized density as a function of the equatorial radius and find the critical rotational parameter. Our computations are extended to certain other physical characteristics (like mass, angular momentum, rotational kinetic energy, etc). We find that our method yields results comparable with those of other reliable methods. REFERENCE: V.S. Geroyannis and F.N. Valvi 2012, International Journal of Modern Physics C, 23, No 5, 1250038:1-15.

  13. General Relativistic Simulations of Magnetized Plasmas around Merging Supermassive Black Holes

    CERN Document Server

    Giacomazzo, Bruno; Miller, M Coleman; Reynolds, Christopher S; van Meter, James R

    2012-01-01

    Coalescing supermassive black hole binaries are produced by the mergers of galaxies and are the most powerful sources of gravitational waves accessible to space-based gravitational observatories. Some such mergers may occur in the presence of matter and magnetic fields and hence generate an electromagnetic counterpart. In this paper we present the first general relativistic simulations of magnetized plasma around merging supermassive black holes using the general relativistic magnetohydrodynamic code Whisky. By considering different magnetic field strengths, going from non-magnetically dominated to magnetically dominated regimes, we explore how magnetic fields affect the dynamics of the plasma and the possible emission of electromagnetic signals. In particular we observe a total amplification of the magnetic field of ~2 orders of magnitude which is driven by the accretion onto the binary and that leads to much stronger electromagnetic signals, more than a factor of 10^4 larger than comparable calculations don...

  14. General Relativistic Simulations of Magnetized Plasmas around Merging Supermassive Black Holes

    Science.gov (United States)

    Giacomazzo, Bruno; Baker, John G.; Miller, M. Coleman; Reynolds, Christopher S.; van Meter, James R.

    2012-06-01

    Coalescing supermassive black hole binaries are produced by the mergers of galaxies and are the most powerful sources of gravitational waves accessible to space-based gravitational observatories. Some such mergers may occur in the presence of matter and magnetic fields and hence generate an electromagnetic counterpart. In this Letter, we present the first general relativistic simulations of magnetized plasma around merging supermassive black holes using the general relativistic magnetohydrodynamic code Whisky. By considering different magnetic field strengths, going from non-magnetically dominated to magnetically dominated regimes, we explore how magnetic fields affect the dynamics of the plasma and the possible emission of electromagnetic signals. In particular, we observe a total amplification of the magnetic field of ~2 orders of magnitude, which is driven by the accretion onto the binary and that leads to much stronger electromagnetic signals, more than a factor of 104 larger than comparable calculations done in the force-free regime where such amplifications are not possible.

  15. RAISHIN: A High-Resolution Three-Dimensional General Relativistic Magnetohydrodynamics Code

    CERN Document Server

    Mizuno, Y; Koide, S; Hardee, P; Fishman, G J; Mizuno, Yosuke; Nishikawa, Ken-Ichi; Koide, Shinji; Hardee, Philip; Fishman, Gerald J.

    2006-01-01

    We have developed a new three-dimensional general relativistic magnetohydrodynamic (GRMHD) code, RAISHIN, using a conservative, high resolution shock-capturing scheme. The numerical fluxes are calculated using the Harten, Lax, & van Leer (HLL) approximate Riemann solver scheme. The flux-interpolated, constrained transport scheme is used to maintain a divergence-free magnetic field. In order to examine the numerical accuracy and the numerical efficiency, the code uses four different reconstruction methods: piecewise linear methods with Minmod and MC slope-limiter function, convex essentially non-oscillatory (CENO) method, and piecewise parabolic method (PPM) using multistep TVD Runge-Kutta time advance methods with second and third-order time accuracy. We describe code performance on an extensive set of test problems in both special and general relativity. Our new GRMHD code has proven to be accurate in second order and has successfully passed with all tests performed, including highly relativistic and mag...

  16. General Relativistic Precession in Small Solar System Bodies

    Science.gov (United States)

    Sekhar, Aswin; Werner, Stephanie; Hoffmann, Volker; Asher, David; Vaubaillon, Jeremie; Hajdukova, Maria; Li, Gongjie

    2016-10-01

    Introduction: One of the greatest successes of the Einstein's General Theory of Relativity (GR) was the correct prediction of the precession of perihelion of Mercury. The closed form expression to compute this precession tells us that substantial GR precession would occur only if the bodies have a combination of both moderately small perihelion distance and semi-major axis. Minimum Orbit Intersection Distance (MOID) is a quantity which helps us to understand the closest proximity of two orbits in space. Hence evaluating MOID is crucial to understand close encounters and collision scenarios better. In this work, we look at the possible scenarios where a small GR precession in argument of pericentre (ω) can create substantial changes in MOID for small bodies ranging from meteoroids to comets and asteroids.Analytical Approach and Numerical Integrations: Previous works have looked into neat analytical techniques to understand different collision scenarios and we use those standard expressions to compute MOID analytically. We find the nature of this mathematical function is such that a relatively small GR precession can lead to drastic changes in MOID values depending on the initial value of ω. Numerical integrations were done with package MERCURY incorporating the GR code to test the same effects. Numerical approach showed the same interesting relationship (as shown by analytical theory) between values of ω and the peaks/dips in MOID values. Previous works have shown that GR precession suppresses Kozai oscillations and this aspect was verified using our integrations. There is an overall agreement between both analytical and numerical methods.Summary and Discussion: We find that GR precession could play an important role in the calculations pertaining to MOID and close encounter scenarios in the case of certain small solar system bodies (depending on their initial orbital elements). Previous works have looked into impact probabilities and collision scenarios on

  17. Noether symmetry and non-Noether conserved quantity of the relativistic holonomic nonconservative systems in general Lie transformations

    Institute of Scientific and Technical Information of China (English)

    Luo Shao-Kai

    2007-01-01

    For a relativistic holonomic nonconservative system, by using the Noether symmetry, a new non-Noether conserved quantity is given under general infinitesimal transformations of groups. On the basis of the theory of invariance of differential equations of motion under general infinitesimal transformations, we construct the relativistic Noether symmetry, Lie symmetry and the condition under which the Noether symmetry is a Lie symmetry under general infinitesimal transformations. By using the Noether symmetry, a new relativistic non-Noether conserved quantity is given which only depends on the variables t, qs and (q)s. An example is given to illustrate the application of the results.

  18. A generalized Jaynes-Cummings model: The relativistic parametric amplifier and a single trapped ion

    Energy Technology Data Exchange (ETDEWEB)

    Ojeda-Guillén, D., E-mail: dojedag@ipn.mx [Escuela Superior de Cómputo, Instituto Politécnico Nacional, Av. Juan de Dios Bátiz esq. Av. Miguel Othón de Mendizábal, Col. Lindavista, Delegación Gustavo A. Madero, C.P. 07738 Ciudad de México (Mexico); Mota, R. D. [Escuela Superior de Ingeniería Mecánica y Eléctrica, Unidad Culhuacán, Instituto Politécnico Nacional, Av. Santa Ana No. 1000, Col. San Francisco Culhuacán, Delegación Coyoacán, C.P. 04430 Ciudad de México (Mexico); Granados, V. D. [Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, Ed. 9, Unidad Profesional Adolfo López Mateos, Delegación Gustavo A. Madero, C.P. 07738 Ciudad de México (Mexico)

    2016-06-15

    We introduce a generalization of the Jaynes-Cummings model and study some of its properties. We obtain the energy spectrum and eigenfunctions of this model by using the tilting transformation and the squeezed number states of the one-dimensional harmonic oscillator. As physical applications, we connect this new model to two important and novelty problems: the relativistic parametric amplifier and the quantum simulation of a single trapped ion.

  19. General Relativistic Radiative Transfer Code in Rotating Black Hole Spacetime: {ARTIST}

    Science.gov (United States)

    Takahashi, Rohta; Umemura, Masayuki

    2016-10-01

    We present a general relativistic radiative transfer code, {ARTIST} (Authentic Radiative Transfer In Space-Time), which is a perfectly causal scheme to pursue the propagation of radiation with absorption and scattering around a Kerr black hole. The code explicitly solves the invariant radiation intensity along null geodesics in the Kerr-Schild coordinates, and therefore properly includes light bending, Doppler boosting, frame dragging, and gravitational redshifts. The notable aspect of {ARTIST} is that it conserves the radiative energy with high accuracy, and is not subject to the numerical diffusion, since the transfer is solved on long characteristics along null geodesics. We first solve the wavefront propagation around a Kerr black hole, which was originally explored by Hanni (1977). This demonstrates repeated wavefront collisions, light bending, and causal propagation of radiation with the speed of light. We show that the decay rate of the total energy of wavefronts near a black hole is determined solely by the black hole spin in late phases, in agreement with analytic expectations. As a result, the {ARTIST} turns out to correctly solve the general relativistic radiation fields until late phases as t ˜ 90M. We also explore the effects of absorption and scattering, and apply this code for a photon wall problem and an orbiting hot spot problem. All the simulations in the present study are performed in the equatorial plane around a Kerr black hole. The {ARTIST} is the first step to realize the general relativistic radiation hydrodynamics.

  20. General relativistic radiative transfer code in rotating black hole space-time: ARTIST

    Science.gov (United States)

    Takahashi, Rohta; Umemura, Masayuki

    2017-02-01

    We present a general relativistic radiative transfer code, ARTIST (Authentic Radiative Transfer In Space-Time), that is a perfectly causal scheme to pursue the propagation of radiation with absorption and scattering around a Kerr black hole. The code explicitly solves the invariant radiation intensity along null geodesics in the Kerr-Schild coordinates, and therefore properly includes light bending, Doppler boosting, frame dragging, and gravitational redshifts. The notable aspect of ARTIST is that it conserves the radiative energy with high accuracy, and is not subject to the numerical diffusion, since the transfer is solved on long characteristics along null geodesics. We first solve the wavefront propagation around a Kerr black hole that was originally explored by Hanni. This demonstrates repeated wavefront collisions, light bending, and causal propagation of radiation with the speed of light. We show that the decay rate of the total energy of wavefronts near a black hole is determined solely by the black hole spin in late phases, in agreement with analytic expectations. As a result, the ARTIST turns out to correctly solve the general relativistic radiation fields until late phases as t ˜ 90 M. We also explore the effects of absorption and scattering, and apply this code for a photon wall problem and an orbiting hotspot problem. All the simulations in this study are performed in the equatorial plane around a Kerr black hole. The ARTIST is the first step to realize the general relativistic radiation hydrodynamics.

  1. General relativistic ray-tracing algorithm for the determination of the electron-positron energy deposition rate from neutrino pair annihilation around rotating neutron and quark stars

    Science.gov (United States)

    Kovács, Z.; Harko, T.

    2011-11-01

    We present a full general relativistic numerical code for estimating the energy-momentum deposition rate (EMDR) from neutrino pair annihilation (?). The source of the neutrinos is assumed to be a neutrino-cooled accretion disc around neutron and quark stars. We calculate the neutrino trajectories by using a ray-tracing algorithm with the general relativistic Hamilton's equations for neutrinos and derive the spatial distribution of the EMDR due to the annihilations of neutrinos and antineutrinos around rotating neutron and quark stars. We obtain the EMDR for several classes of rotating neutron stars, described by different equations of state of the neutron matter, and for quark stars, described by the Massachusetts Institute of Technology (MIT) bag model equation of state and in the colour-flavour-locked (CFL) phase. The distribution of the total annihilation rate of the neutrino-antineutrino pairs around rotating neutron and quark stars is studied for isothermal discs and accretion discs in thermodynamical equilibrium. We demonstrate both the differences in the equations of state for neutron and quark matter and rotation with the general relativistic effects significantly modify the EMDR of the electrons and positrons generated by the neutrino-antineutrino pair annihilation around compact stellar objects, as measured at infinity.

  2. The truthful signalling hypothesis: an explicit general equilibrium model.

    Science.gov (United States)

    Hausken, Kjell; Hirshleifer, Jack

    2004-06-21

    In mating competition, the truthful signalling hypothesis (TSH), sometimes known as the handicap principle, asserts that higher-quality males signal while lower-quality males do not (or else emit smaller signals). Also, the signals are "believed", that is, females mate preferentially with higher-signalling males. Our analysis employs specific functional forms to generate analytic solutions and numerical simulations that illuminate the conditions needed to validate the TSH. Analytic innovations include: (1) A Mating Success Function indicates how female mating choices respond to higher and lower signalling levels. (2) A congestion function rules out corner solutions in which females would mate exclusively with higher-quality males. (3) A Malthusian condition determines equilibrium population size as related to per-capita resource availability. Equilibria validating the TSH are achieved over a wide range of parameters, though not universally. For TSH equilibria it is not strictly necessary that the high-quality males have an advantage in terms of lower per-unit signalling costs, but a cost difference in favor of the low-quality males cannot be too great if a TSH equilibrium is to persist. And although the literature has paid less attention to these points, TSH equilibria may also fail if: the quality disparity among males is too great, or the proportion of high-quality males in the population is too large, or if the congestion effect is too weak. Signalling being unprofitable in aggregate, it can take off from a no-signalling equilibrium only if the trait used for signalling is not initially a handicap, but instead is functionally useful at low levels. Selection for this trait sets in motion a bandwagon, whereby the initially useful indicator is pushed by male-male competition into the domain where it does indeed become a handicap.

  3. General-relativistic resistive magnetohydrodynamics in three dimensions: Formulation and tests

    Science.gov (United States)

    Dionysopoulou, Kyriaki; Alic, Daniela; Palenzuela, Carlos; Rezzolla, Luciano; Giacomazzo, Bruno

    2013-08-01

    We present a new numerical implementation of the general-relativistic resistive magnetohydrodynamics (MHD) equations within the Whisky code. The numerical method adopted exploits the properties of implicit-explicit Runge-Kutta numerical schemes to treat the stiff terms that appear in the equations for large electrical conductivities. Using tests in one, two, and three dimensions, we show that our implementation is robust and recovers the ideal-MHD limit in regimes of very high conductivity. Moreover, the results illustrate that the code is capable of describing scenarios in a very wide range of conductivities. In addition to tests in flat spacetime, we report simulations of magnetized nonrotating relativistic stars, both in the Cowling approximation and in dynamical spacetimes. Finally, because of its astrophysical relevance and because it provides a severe tested for general-relativistic codes with dynamical electromagnetic fields, we study the collapse of a nonrotating star to a black hole. We show that also in this case our results on the quasinormal mode frequencies of the excited electromagnetic fields in the Schwarzschild background agree with the perturbative studies within 0.7% and 5.6% for the real and the imaginary part of the ℓ=1 mode eigenfrequency, respectively. Finally we provide an estimate of the electromagnetic efficiency of this process.

  4. A New Formulation for General Relativistic Force-Free Electrodynamics and Its Applications

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We formulate the general relativistic force-free electrodynamics in a new 3+1 language. In this formulation, when we have properly defined electric and magnetic fields, the covariant Maxwell equations could be cast in the traditional form with new vacuum con stitutive constraint equations. The fundamental equation governing a stationary, axisymmet ric force-free black hole magnetosphere is derived using this formulation which recasts the Grad-Shafranov equation in a simpler way. Compared to the classic 3+1 system of Thorne and MacDonald, the new system of 3+1 equations is more suitable for numerical use for it keeps the hyperbolic structure of the electrodynamics and avoids the singularity at the event horizon. This formulation could be readily extended to non-relativistic limit and find applications in flat spacetime. We investigate its application to disk wind, black hole magnetosphere and solar physics in both flat and curved spacetime.

  5. Analytical Solution of Relativistic Few-Body Bound Systems with a Generalized Yukawa Potential

    Science.gov (United States)

    Aslanzadeh, M.; Rajabi, A. A.

    2016-03-01

    We have investigated in this paper the few-body bound systems in a simple semi-relativistic scheme. For this aim, we introduced a spin independent relativistic description for a few-identical body system by presenting the analytical solution of few-particle Klein-Gordon equation. Performing calculations in D-dimensional configuration on the basis of the hypercentral approach, we reduced the few-body Klein-Gordon equation to a Schrödinger-like form. This equation is solved by using the Nikiforov-Uvarov method, through which the energy equations and eigenfunctions for a few-body bound system are obtained. We used the spin- and isospin-independent generalized Yukawa potential in our calculations, and the dependence of the few-body binding energies on the potential parameters has been investigated.

  6. Relativistic calculations of coalescing binary neutron stars

    Indian Academy of Sciences (India)

    Joshua Faber; Phillippe Grandclément; Frederic Rasio

    2004-10-01

    We have designed and tested a new relativistic Lagrangian hydrodynamics code, which treats gravity in the conformally flat approximation to general relativity. We have tested the resulting code extensively, finding that it performs well for calculations of equilibrium single-star models, collapsing relativistic dust clouds, and quasi-circular orbits of equilibrium solutions. By adding a radiation reaction treatment, we compute the full evolution of a coalescing binary neutron star system. We find that the amount of mass ejected from the system, much less than a per cent, is greatly reduced by the inclusion of relativistic gravitation. The gravity wave energy spectrum shows a clear divergence away from the Newtonian point-mass form, consistent with the form derived from relativistic quasi-equilibrium fluid sequences.

  7. On the General Solution to Einstein's Vacuum Field and Its Implications for Relativistic Degeneracy

    Directory of Open Access Journals (Sweden)

    Crothers S. J.

    2005-04-01

    Full Text Available The general solution to Einstein’s vacuum field equations for the point-mass in all its configurations must be determined in such a way as to provide a means by which an infinite sequence of particular solutions can be readily constructed. It is from such a solution that the underlying geometry of Einstein’s universe can be rightly explored. I report here on the determination of the general solution and its consequences for the theoretical basis of relativistic degeneracy, i.e. gravitational collapse and the black hole.

  8. Stochastic Oscillations of General Relativistic Disks Described by a Fractional Langevin Equation with Fractional Gaussian Noise

    Indian Academy of Sciences (India)

    Wang Zhi-Yun; Chen Pei-Jie

    2016-06-01

    A generalized Langevin equation driven by fractional Brownian motion is used to describe the vertical oscillations of general relativistic disks. By means of numerical calculation method, the displacements, velocities and luminosities of oscillating disks are explicitly obtained for different Hurst exponent $H$. The results show that as $H$ increases, the energies and luminosities of oscillating disk are enhanced, and the spectral slope at high frequencies of the power spectrum density of disk luminosity is also increased. This could explain the observational features related to the Intra Day Variability of the BL Lac objects.

  9. A general method to study equilibrium partitioning of macromolecules

    DEFF Research Database (Denmark)

    The distribution of macromolecules between a confined microscopic solution and a macroscopic bulk solution plays an important role in understanding separation processes such as Size Exclusion Chromatography (SEC). In this study, we have developed an efficient computational algorithm for obtaining...... the equilibrium partition coefficient (pore-to-bulk concentration ratio) and the concentration profile inside the confining geometry. The algorithm involves two steps. First, certain characteristic structure properties of the studied macromolecule are obtained by sampling its configuration space, and second those...... data are used for the computation of partition coefficient and concentration profile for any confinement size. Our algorithm is versatile to the model and type of the macromolecule studied, and is capable of handling three types of confining geometries (slit, rectangular channel and rectangular box...

  10. PREDICTOR-CORRECTOR ALGORITHMS FOR SOLVING GENERALIZED MIXED IMPLICIT QUASI-EQUILIBRIUM PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    DING Xie-ping; LIN Yen-cherng; YAO Jen-chih

    2006-01-01

    A new class of generalized mixed implicit quasi-equilibrium problems (GMIQEP) with four-functions is introduced and studied. The new class of equilibrium problems includes many known generalized equilibrium problems and generalized mixed implicit quasi-variational inequality problems as many special cases. By employing the auxiliary principle technique, some predictor-corrector iterative algorithms for solving the GMIQEP are suggested and analyzed. The convergence of the suggested algorithm only requires the continuity and the partially relaxed implicit strong monotonicity of the mappings.

  11. General stochastic variational formulation for the oligopolistic market equilibrium problem with excesses

    Science.gov (United States)

    Barbagallo, Annamaria; Di Meglio, Guglielmo; Mauro, Paolo

    2017-07-01

    The aim of the paper is to study, in a Hilbert space setting, a general random oligopolistic market equilibrium problem in presence of both production and demand excesses and to characterize the random Cournot-Nash equilibrium principle by means of a stochastic variational inequality. Some existence results are presented.

  12. Kinetic behavior of the general modifier mechanism of Botts and Morales with non-equilibrium binding

    CERN Document Server

    Jia, Chen; Qian, Min-Ping; Jiang, Da-Quan; Zhang, Yu-Ping

    2010-01-01

    In this paper, we thoroughly investigate the kinetic behavior of the general modifier mechanism of Botts and Morales at both equilibrium steady state assuming equilibrium substrate- and modifier-binding steps and non-equilibrium steady state (NESS) without assuming equilibrium binding steps. We introduce the net flux into discussion and propose a method which gains a strong advantage over early approaches involving King-Atman method and even the numerical computations in dealing with the cyclic reaction systems. Using this new approach, the expression of product rate at NESS gives clear biophysical significance. Moreover, we classify the kinetic behavior of the modifier into three categories, namely hyperbolic behavior, bell-shaped behavior, and switching behavior. It turns out that a modifier cannot be regarded as overall activator or inhibitor when the reaction system is not at equilibrium. The switching-behaved modifier may convert between activator and inhibitor via the general modifier mechanism when the...

  13. The contribution of several Nobel Laureates in the development of the Theory of general economic equilibrium

    Directory of Open Access Journals (Sweden)

    Florentina Xhelili Krasniqi

    2016-12-01

    Full Text Available Nobel Laureates with their contributions to the development of the theory of general equilibrium have enabled this theory to be one of the most important for theoretical and practical analysis of the overall economy and the efficient use of economic resources. Results of the research showing that contributions of Nobel Laureates in the economy belong to two main frameworks of development of the general equilibrium theory: one was the mathematical model of general equilibrium developed by John R. Hicks (1939, Kenneth J.Arrow (1951 and Gerard Debreu (1954 and second frames of general equilibrium belongs to Paul A. Samuelson (1958. To highlight the contributions of these Nobel laureates in the development of the theory of general equilibrium have been selected and are presented in the paper some views, estimates and assumptions that have contributed not only in solving concrete problems, but also to the development of economic science in general. Their works represent a synthesis of theoretical and practical aspects of treatment of general equilibrium which are the starting point for further research in this field.

  14. The 2D surfaces that generate Newtonian and general relativistic orbits with small eccentricities

    CERN Document Server

    Middleton, Chad A

    2015-01-01

    Embedding diagrams prove to be quite useful when learning general relativity as they offer a way of visualizing spacetime curvature through warped two dimensional (2D) surfaces. In this manuscript we present a different 2D construct that also serves as a useful conceptual tool for gaining insight into gravitation, in particular, orbital dynamics - namely the cylindrically symmetric surfaces that generate Newtonian and general relativistic orbits with small eccentricities. Although we first show that no such surface exists that can exactly reproduce the arbitrary bound orbits of Newtonian gravitation or of general relativity (or, more generally, of any spherically symmetric potential), surfaces do exist that closely approximate the resulting orbital motion for small eccentricities; exactly the regime that describes the motion of the solar system planets. These surfaces help to illustrate the similarities, as well as the differences, between the two theories of gravitation (i.e. stationary elliptical orbits in ...

  15. Magnetic collimation of meridional-self-similar general relativistic MHD flows

    Science.gov (United States)

    Globus, Noemie; Sauty, Christophe; Cayatte, Véronique; Celnikier, Ludwik M.

    2014-06-01

    We present a model for the spine of relativistic Magnetohydrodynamics outflows in the Kerr geometry. Meridional self-similarity is invoked to derive semianalytical solutions close to the polar axis. The study of the energy conservation along a particular field line gives a simple criterion for the collimation of jets. Such parameter have already been derived in the classical case by Sauty et al. 1999 and also extended to the Schwarzschild metric by Meliani et al. 2006. We generalize the same study to the Kerr metric. We show that the rotation of the black hole increases the magnetic self-confinement.

  16. Magnetic collimation of meridional-self-similar general relativistic MHD flows

    CERN Document Server

    Globus, Noemie; Cayatte, Véronique; Celnikier, Ludwik M

    2014-01-01

    We present a model for the spine of relativistic MHD outflows in the Kerr geometry. Meridional self-similarity is invoked to derive semi-analytical solutions close to the polar axis. The study of the energy conservation along a particular field line gives a simple criterion for the collimation of jets. Such parameter have already been derived in the classical case by Sauty et al. 1999 and also extended to the Schwarzschild metric by Meliani et al. 2006. We generalize the same study to the Kerr metric. We show that the rotation of the black hole increases the magnetic self-confinement.

  17. A general relativistic approach to the Navarro Frenk White galactic halos

    Science.gov (United States)

    Matos, Tonatiuh; Núñez, Darío; Sussman, Roberto A.

    2004-11-01

    Although galactic dark matter halos are basically Newtonian structures, the study of their interplay with large-scale cosmic evolution and with relativistic effects, such as gravitational lenses, quintessence sources or gravitational waves, makes it necessary to obtain adequate relativistic descriptions for these self-gravitating systems. With this purpose in mind, we construct a post-Newtonian fluid framework for the 'Navarro Frenk White' (NFW) models of galactic halos that follow from N-body numerical simulations. Since these simulations are unable to resolve regions very near the halo centre, the extrapolation of the fitting formula leads to a spherically averaged 'universal' density profile that diverges at the origin. We remove this inconvenient feature by replacing a small central region of the NFW halo with an interior Schwarzschild solution with constant density, continuously matched to the remaining NFW spacetime. A model of a single halo, as an isolated object with finite mass, follows by smoothly matching the NFW spacetime to a Schwarzschild vacuum exterior along the virial radius, the physical 'cut-off' customarily imposed, as the mass associated with NFW profiles diverges asymptotically. Numerical simulations assume weakly interacting collisionless particles, hence we suggest that NFW halos approximately satisfy an 'ideal gas' type of equation of state, where mass-density is the dominant rest-mass contribution to matter-energy, with the internal energy contribution associated with an anisotropic kinetic pressure. We show that, outside the central core, this pressure and the mass density roughly satisfy a polytropic relation. Since stellar polytropes are the equilibrium configurations in Tsallis' non-extensive formalism of statistical mechanics, we argue that NFW halos might provide a rough empirical estimate of the free parameter q of Tsallis' formalism.

  18. Regional development policies modelling: a framework of general equilibrium

    OpenAIRE

    Kancs, Artis

    2001-01-01

    The changes the rural economy and society experience today are wide ranging and complex. They stem to a large extent from changing socio-economic norms and values in a society as well as from the changes of the global economy, of the market policy and trade rules. These changes affect however, not only sectoral markets, but local economies and rural areas in general (FERMAN 1999). At the same time rural economies have to meet rising environmental and recreational claims of the society, which ...

  19. The role of currents distribution in general relativistic equilibria of magnetized neutron stars

    CERN Document Server

    Bucciantini, N; Del Zanna, L

    2014-01-01

    Magnetic fields play a critical role in the phenomenology of neutron stars. There is virtually no observable aspect which is not governed by them. Despite this, only recently efforts have been done to model magnetic fields in the correct general relativistic regime, characteristic of these compact objects. In this work we present, for the first time a comprehensive and detailed parameter study, in general relativity, of the role that the current distribution, and the related magnetic field structure, have in determining the precise structure of neutron stars. In particular, we show how the presence of localized currents can modify the field strength at the stellar surface, and we look for general trends, both in terms of energetic properties, and magnetic field configurations. Here we verify that, among other things, for a large class of different current distributions the resulting magnetic configurations are always dominated by the poloidal component of the current.

  20. GENERAL RELATIVISTIC SIMULATIONS OF MAGNETIZED PLASMAS AROUND MERGING SUPERMASSIVE BLACK HOLES

    Energy Technology Data Exchange (ETDEWEB)

    Giacomazzo, Bruno [JILA, University of Colorado and National Institute of Standards and Technology, 440 UCB, Boulder, CO 80309 (United States); Baker, John G.; Van Meter, James R. [Gravitational Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 21114 (United States); Coleman Miller, M.; Reynolds, Christopher S. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)

    2012-06-10

    Coalescing supermassive black hole binaries are produced by the mergers of galaxies and are the most powerful sources of gravitational waves accessible to space-based gravitational observatories. Some such mergers may occur in the presence of matter and magnetic fields and hence generate an electromagnetic counterpart. In this Letter, we present the first general relativistic simulations of magnetized plasma around merging supermassive black holes using the general relativistic magnetohydrodynamic code Whisky. By considering different magnetic field strengths, going from non-magnetically dominated to magnetically dominated regimes, we explore how magnetic fields affect the dynamics of the plasma and the possible emission of electromagnetic signals. In particular, we observe a total amplification of the magnetic field of {approx}2 orders of magnitude, which is driven by the accretion onto the binary and that leads to much stronger electromagnetic signals, more than a factor of 10{sup 4} larger than comparable calculations done in the force-free regime where such amplifications are not possible.

  1. Electronic Commerce and Developing Countries: a Computable General Equilibrium Analysis

    Directory of Open Access Journals (Sweden)

    Juan Pizarro Ríos

    2002-06-01

    Full Text Available Es ampliamente reconocido que el comercio electrónico reduce costos de transacción,incrementa la eficiencia y produce importantes cambios en la administración ylos procesos productivos de los negocios. Asimismo, en el ámbito macroeconómico,un creciente número de economistas reconocen que el comercio electrónicoBusiness-to-Business puede tener un impacto positivo en la productividad y el crecimientode los paises desarrollados. Este articulo hace un análisis cuantitativo delimpacto del comercio electrónico sobre la economía global cuando las economías endesarrollo se atrasan tecnológicamente y cuando alcanzan a los países desarrollados.El análisis se centra en la reducción de costos y asume que el comercio electrónicopuede reducir costos de servicios, particularmente, en el comercio al por mayory por menor, transporte, así como en el sector financiero. Los experimentos se basanen un modelo computable de equilibrio general, ei GTAP, de trece sectores y seisregiones. Las reducciones de costos en el sector servicios son simuladas por un crecimientode la productividad. A excepción de los servicios de transporte acuático, losresultados en general revelan que cuando los países en desarrollo se atrasan tecnológicamente,la brecha entre el ingreso de los paises en desarrollo y los países desarrolladosse incrementará. Los países en desarrollo perderán bienestar y verán deterioradossus términos de intercambio y reducidos sus salarios. Los resultadostambién indican que una convergencia en la productividad del sector servicios ofrecela posibilidad a los países en desarrollo de incrementar su competitividad e incrementarla producción, los salarios y el bienestar.

  2. Generalized fluctuation-dissipation relation and effective temperature in off-equilibrium colloids

    Science.gov (United States)

    Maggi, Claudio; di Leonardo, Roberto; Dyre, Jeppe C.; Ruocco, Giancarlo

    2010-03-01

    The fluctuation-dissipation theorem (FDT), a fundamental result of equilibrium statistical physics, can be violated when a system is taken out of equilibrium. A generalization of FDT has been theoretically proposed for out-of-equilibrium systems; the kinetic temperature entering the fluctuation-dissipation relation (FDR) is substituted by a time-scale-dependent effective temperature. We combine the measurements of the correlation function of the rotational dynamics of colloidal particles obtained via dynamic light scattering with those of the birefringence response to study the generalized FDR in an off-equilibrium Laponite suspension undergoing aging. (i) We find that the FDT is strongly violated in the early stage of the aging process and is gradually recovered as the aging time increases and (ii) we determine the aging-time evolution of the effective temperature, comparing our results with those of previous experiments.

  3. The General Equilibrium Model with Joint Ownership of the Corporation (Voting Stock and the Core),

    Science.gov (United States)

    general equilibrium system. The point specifically is that the Arrow-Debreu treatment of the joint ownership of industry by introducing shares which can be treated, requires further specification. The need for further specification can be seen immediately when this model is examined not for the competitive equilibrium but for the core. It is well known that the competitive equilibrium is contained within the core. However it will be shown that unless extra conditions are imposed on the control of stock the resultant game may have no core whatsoever and hence no competitive

  4. A General Equilibrium Self-Employment Theory based on Human Capital Differences

    OpenAIRE

    Gerardo Jacobs

    2004-01-01

    Since a big proportion of the labor force in developing countries belongs to the self-employment sector, it is desirable to build models to study these dynamics. Previous works study the occupational choices of agents. The most recent ones build general equilibrium economies with three types of agents: entrepreneurs, workers and self-employees. Unfortunately, in theses works at equilibrium, workers are poorer than agents in self-employment. Data for developing countries shows that self-employ...

  5. Newtonian analogue of static general relativistic spacetimes: An extension to naked singularities

    CERN Document Server

    Ghosh, Shubhrangshu; Bhadra, Arunava

    2015-01-01

    We formulate a generic Newtonian like analogous potential for static spherically symmetric general relativistic (GR) spacetime, and subsequently derived proper Newtonian like analogous potential corresponding to Janis-Newman-Winicour (JNW) and Reissner-Nordstr\\"{o}m (RN) spacetimes, both exhibiting naked singularities. The derived potentials found to reproduce the entire GR features including the orbital dynamics of the test particle motion and the orbital trajectories, with precise accuracy. The nature of the particle orbital dynamics including their trajectory profiles in JNW and RN geometries show altogether different behavior with distinctive traits as compared to the nature of particle dynamics in Schwarzschild geometry. Exploiting the Newtonian like analogous potentials, we found that the radiative efficiency of a geometrically thin and optically thick Keplerian accretion disk around naked singularities corresponding to both JNW and RN geometries, in general, is always higher than that for Schwarzschild...

  6. A New Multi-Dimensional General Relativistic Neutrino Hydrodynamics Code for Core-Collapse Supernovae II. Relativistic Explosion Models of Core-Collapse Supernovae

    CERN Document Server

    Mueller, B; Marek, A

    2012-01-01

    We present the first two-dimensional general relativistic (GR) simulations of stellar core collapse and explosion with the CoCoNuT hydrodynamics code in combination with the VERTEX solver for energy-dependent, three-flavor neutrino transport, using the extended conformal flatness condition for approximating the spacetime metric and a ray-by-ray-plus ansatz to tackle the multi-dimensionality of the transport. For both of the investigated 11.2 and 15 solar mass progenitors we obtain successful, though seemingly marginal, neutrino-driven supernova explosions. This outcome and the time evolution of the models basically agree with results previously obtained with the PROMETHEUS hydro solver including an approximative treatment of relativistic effects by a modified Newtonian potential. However, GR models exhibit subtle differences in the neutrinospheric conditions compared to Newtonian and pseudo-Newtonian simulations. These differences lead to significantly higher luminosities and mean energies of the radiated ele...

  7. Behavior of solution set for bilevel generalized mixed equilibrium problems in topological vector spaces

    Institute of Scientific and Technical Information of China (English)

    丁协平

    2014-01-01

    A new bilevel generalized mixed equilibrium problem (BGMEP) is introduced and studied in topological vector spaces. By using a minimax inequality, the existence of solutions and the behavior of solution set for the BGMEP are studied under quite mild conditions. These results are new and generalize some recent results in this field.

  8. A general theory of non-equilibrium dynamics of lipid-protein fluid membranes

    DEFF Research Database (Denmark)

    Lomholt, Michael Andersen; Hansen, Per Lyngs; Miao, L.

    2005-01-01

    We present a general and systematic theory of non-equilibrium dynamics of multi-component fluid membranes, in general, and membranes containing transmembrane proteins, in particular. Developed based on a minimal number of principles of statistical physics and designed to be a meso...

  9. Fully General Relativistic Simulations of Black Hole-Neutron Star Mergers

    CERN Document Server

    Etienne, Zachariah B; Liu, Yuk Tung; Shapiro, Stuart L; Taniguchi, Keisuke; Baumgarte, Thomas W

    2007-01-01

    Black hole-neutron star (BHNS) binaries are expected to be among the leading sources of gravitational waves observable by ground-based detectors, and may be the progenitors of short-hard gamma ray bursts (SGRBs) as well. Here, we discuss our new fully general relativistic calculations of merging BHNS binaries, which use high-accuracy, low-eccentricity, conformal thin-sandwich configurations as initial data. Our evolutions are performed using the moving puncture method and include a fully relativistic, high-resolution shock-capturing hydrodynamics treatment. Focusing on systems in which the neutron star is irrotational and the black hole is nonspinning with a 3:1 mass ratio, we investigate the inspiral, merger, and disk formation in the system. We find that the vast majority of material is promptly accreted and no more than 3% of the neutron star's rest mass is ejected into a tenuous, gravitationally bound disk. We find similar results for mass ratios of 2:1 and 1:1, even when we reduce the NS compaction in th...

  10. GLOBAL GENERAL RELATIVISTIC MAGNETOHYDRODYNAMIC SIMULATIONS OF BLACK HOLE ACCRETION FLOWS: A CONVERGENCE STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Shiokawa, Hotaka; Dolence, Joshua C.; Gammie, Charles F. [Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Noble, Scott C. [Center for Computational Relativity and Gravitation, School of Mathematical Sciences, Rochester Institute of Technology, Rochester, NY 14623 (United States)

    2012-01-10

    Global, general relativistic magnetohydrodynamic (GRMHD) simulations of non-radiative, magnetized disks are widely used to model accreting black holes. We have performed a convergence study of GRMHD models computed with HARM3D. The models span a factor of four in linear resolution, from 96 Multiplication-Sign 96 Multiplication-Sign 64 to 384 Multiplication-Sign 384 Multiplication-Sign 256. We consider three diagnostics of convergence: (1) dimensionless shell-averaged quantities such as plasma {beta}; (2) the azimuthal correlation length of fluid variables; and (3) synthetic spectra of the source including synchrotron emission, absorption, and Compton scattering. Shell-averaged temperature is, except for the lowest resolution run, nearly independent of resolution; shell-averaged plasma {beta} decreases steadily with resolution but shows signs of convergence. The azimuthal correlation lengths of density, internal energy, and temperature decrease steadily with resolution but show signs of convergence. In contrast, the azimuthal correlation length of magnetic field decreases nearly linearly with grid size. We argue by analogy with local models, however, that convergence should be achieved with another factor of two in resolution. Synthetic spectra are, except for the lowest resolution run, nearly independent of resolution. The convergence behavior is consistent with that of higher physical resolution local model ({sup s}hearing box{sup )} calculations and with the recent non-relativistic global convergence studies of Hawley et al.

  11. Exact solutions of the general equilibrium shape equations in a general power model of free energy for DNA structures

    Science.gov (United States)

    Yavari, Morteza

    2014-02-01

    The aim of this paper is to generalize the results of the Feoli's formalism (A. Feoli et al., Nucl. Phys. B 705, 577 (2005)) for DNA structures. The exact solutions of the general equilibrium shape equations for a general power model of free energy are investigated using the Feoli's formalism. The free energy of B- to Z-DNA transition is also calculated in this formalism.

  12. Relativistic diffusion.

    Science.gov (United States)

    Haba, Z

    2009-02-01

    We discuss relativistic diffusion in proper time in the approach of Schay (Ph.D. thesis, Princeton University, Princeton, NJ, 1961) and Dudley [Ark. Mat. 6, 241 (1965)]. We derive (Langevin) stochastic differential equations in various coordinates. We show that in some coordinates the stochastic differential equations become linear. We obtain momentum probability distribution in an explicit form. We discuss a relativistic particle diffusing in an external electromagnetic field. We solve the Langevin equations in the case of parallel electric and magnetic fields. We derive a kinetic equation for the evolution of the probability distribution. We discuss drag terms leading to an equilibrium distribution. The relativistic analog of the Ornstein-Uhlenbeck process is not unique. We show that if the drag comes from a diffusion approximation to the master equation then its form is strongly restricted. The drag leading to the Tsallis equilibrium distribution satisfies this restriction whereas the one of the Jüttner distribution does not. We show that any function of the relativistic energy can be the equilibrium distribution for a particle in a static electric field. A preliminary study of the time evolution with friction is presented. It is shown that the problem is equivalent to quantum mechanics of a particle moving on a hyperboloid with a potential determined by the drag. A relation to diffusions appearing in heavy ion collisions is briefly discussed.

  13. General-relativistic monopole magnetosphere of neutron stars: a pseudo-spectral discontinuous Galerkin approach

    CERN Document Server

    Pétri, J

    2014-01-01

    The close vicinity of neutron stars remains poorly constrained by observations. Although plenty of data are available for the peculiar class of pulsars we are still unable to deduce the underlying plasma distribution in their magnetosphere. In the present paper, we try to unravel the magnetospheric structure starting from basic physics principles and reasonable assumptions about the magnetosphere. Beginning with the monopole force-free case, we compute accurate general-relativistic solutions for the electromagnetic field around a slowly rotating magnetized neutron star. Moreover, here we address this problem by including the important effect of plasma screening. This is achieved by solving the time-dependent Maxwell equations in a curved space-time following the 3+1~formalism. We improved our previous numerical code based on pseudo-spectral methods in order to allow for possible discontinuities in the solution. Our algorithm based on a multi-domain decomposition of the simulation box belongs to the discontinu...

  14. Parsec-scale Faraday Rotation Measures from General Relativistic MHD Simulations of Active Galactic Nuclei Jets

    CERN Document Server

    Broderick, Avery E

    2010-01-01

    For the first time it has become possible to compare global 3D general relativistic magnetohydrodynamic (GRMHD) jet formation simulations directly to very-long baseline interferometric multi-frequency polarization observations of the pc-scale structure of active galactic nucleus (AGN) jets. Unlike the jet emission, which requires post hoc modeling of the non-thermal electrons, the Faraday rotation measures (RMs) depend primarily upon simulated quantities and thus provide a robust way in which to confront simulations with observations. We compute RM distributions of 3D global GRMHD jet formation simulations, with which we explore the dependence upon model and observational parameters, emphasizing the signatures of structures generic to the theory of MHD jets. With typical parameters, we find that it is possible to reproduce the observed magnitudes and many of the structures found in AGN jet RMs, including the presence of transverse RM gradients. In our simulations the RMs are generated within a smooth extensio...

  15. General Relativistic Magnetohydrodynamic Simulations of the Hard State as a Magnetically-Dominated Accretion Flow

    CERN Document Server

    Fragile, P Chris

    2008-01-01

    (Abridged) We present one of the first physically-motivated two-dimensional general relativistic magnetohydrodynamic (GRMHD) numerical simulations of a radiatively-cooled black-hole accretion disk. The fiducial simulation combines a total-energy-conserving formulation with a radiative cooling function, which includes bremsstrahlung, synchrotron, and Compton effects. By comparison with other simulations we show that in optically thin advection-dominated accretion flows, radiative cooling can significantly affect the structure, without necessarily leading to an optically thick, geometrically thin accretion disk. We further compare the results of our radiatively-cooled simulation to the predictions of a previously developed analytic model for such flows. For the very low stress parameter and accretion rate found in our simulated disk, we closely match a state called the "transition" solution between an outer advection-dominated accretion flow and what would be a magnetically-dominated accretion flow (MDAF) in th...

  16. General relativistic radiative transfer in hot astrophysical plasmas a characteristic approach

    CERN Document Server

    Zane, S; Nobili, L; Erna, M; Zane, Silvia; Turolla, Roberto; Nobili, Luciano; Erna, Myris

    1996-01-01

    In this paper we present a characteristic method for solving the transfer equation in differentially moving media in a curved spacetime. The method is completely general, but its capabilities are exploited at best in presence of symmetries, when the existence of conserved quantities allows to derive analytical expressions for the photon trajectories in phase space. In spherically--symmetric, stationary configurations the solution of the transfer problem is reduced to the integration of a single ordinary differential equation along the bi--parametric family of characteristic rays. Accurate expressions for the radiative processes relevant to continuum transfer in a hot astrophysical plasma have been used in evaluating the source term, including relativistic e--p, e--e bremsstrahlung and Compton scattering. A numerical code for the solution of the transfer problem in moving media in a Schwarzschild spacetime has been developed and tested. Some applications, concerning ``hot'' and ``cold'' accretion onto non--rot...

  17. Semi-implicit scheme for treating radiation under M1 closure in general relativistic conservative fluid dynamics codes

    CERN Document Server

    Sdowski, Aleksander; Tchekhovskoy, Alexander; Zhu, Yucong

    2012-01-01

    A numerical scheme is described for including radiation in multi-dimensional general-relativistic conservative fluid dynamics codes. In this method, a covariant form of the M1 closure scheme is used to close the radiation moments, and the radiative source terms are treated semi-implicitly in order to handle both optically thin and optically thick regimes. The scheme has been implemented in a conservative general relativistic radiation hydrodynamics code KORAL. The robustness of the code is demonstrated on a number of test problems, including radiative relativistic shock tubes, static radiation pressure supported atmosphere, shadows, beams of light in curved spacetime, and radiative Bondi accretion. The advantages of M1 closure relative to other approaches such as Eddington closure and flux-limited diffusion are discussed, and its limitations are also highlighted.

  18. Dissipative collapse of axially symmetric, general relativistic, sources: A general framework and some applications

    CERN Document Server

    Herrera, L; Ibañez, J; Ospino, J

    2014-01-01

    We carry out a general study on the collapse of axially (and reflection) symmetric sources in the context of general relativity. All basic equations and concepts required to perform such a general study are deployed. These equations are written down for a general anisotropic dissipative fluid. The proposed approach allows for analytical studies as well as for numerical applications. A causal transport equation derived from the Israel-Stewart theory is applied, to discuss some thermodynamic aspects of the problem. A set of scalar functions (the structure scalars) derived from the orthogonal splitting of the Riemann tensor are calculated and their role in the dynamics of the source is clearly exhibited. The characterization of the gravitational radiation emitted by the source is discussed.

  19. General Relativistic Magnetohydrodynamic Simulations of Magnetically Choked Accretion Flows around Black Holes

    Energy Technology Data Exchange (ETDEWEB)

    McKinney, Jonathan C.; Tchekhovskoy, Alexander; Blandford, Roger D.

    2012-04-26

    Black hole (BH) accretion flows and jets are qualitatively affected by the presence of ordered magnetic fields. We study fully three-dimensional global general relativistic magnetohydrodynamic (MHD) simulations of radially extended and thick (height H to cylindrical radius R ratio of |H/R| {approx} 0.2-1) accretion flows around BHs with various dimensionless spins (a/M, with BH mass M) and with initially toroidally-dominated ({phi}-directed) and poloidally-dominated (R-z directed) magnetic fields. Firstly, for toroidal field models and BHs with high enough |a/M|, coherent large-scale (i.e. >> H) dipolar poloidal magnetic flux patches emerge, thread the BH, and generate transient relativistic jets. Secondly, for poloidal field models, poloidal magnetic flux readily accretes through the disk from large radii and builds-up to a natural saturation point near the BH. While models with |H/R| {approx} 1 and |a/M| {le} 0.5 do not launch jets due to quenching by mass infall, for sufficiently high |a/M| or low |H/R| the polar magnetic field compresses the inflow into a geometrically thin highly non-axisymmetric 'magnetically choked accretion flow' (MCAF) within which the standard linear magneto-rotational instability is suppressed. The condition of a highly-magnetized state over most of the horizon is optimal for the Blandford-Znajek mechanism that generates persistent relativistic jets with and 100% efficiency for |a/M| {approx}> 0.9. A magnetic Rayleigh-Taylor and Kelvin-Helmholtz unstable magnetospheric interface forms between the compressed inflow and bulging jet magnetosphere, which drives a new jet-disk oscillation (JDO) type of quasi-periodic oscillation (QPO) mechanism. The high-frequency QPO has spherical harmonic |m| = 1 mode period of {tau} {approx} 70GM/c{sup 3} for a/M {approx} 0.9 with coherence quality factors Q {approx}> 10. Overall, our models are qualitatively distinct from most prior MHD simulations (typically, |H/R| << 1 and poloidal flux is

  20. The Extended Generalized Cost Concept and its Application in Freight Transport and General Equilibrium Modeling

    NARCIS (Netherlands)

    Tavasszy, L.; Davydenko, I.; Ruijgrok, K.

    2009-01-01

    The integration of Spatial Equilibrium models and Freight transport network models is important to produce consistent scenarios for future freight transport demand. At various spatial scales, we see the changes in production, trade, logistics networking and transportation, being driven by mass-indiv

  1. Frictions, Persistence, and Central Bank Policy in an Experimental Dynamic Stochastic General Equilibrium Economy

    NARCIS (Netherlands)

    Noussair, C.N.; Pfajfar, D.; Zsiros, J.

    2011-01-01

    New Keynesian dynamic stochastic general equilibrium models are the principal paradigm currently employed for central bank policymaking. In this paper, we construct experimental economies, populated with human subjects, with the structure of a New Keynesian DSGE model. We give individuals monetary

  2. Macroeconomic effects of CO2 emission limits : A computable general equilibrium analysis for China

    NARCIS (Netherlands)

    Zhang, ZX

    1998-01-01

    The study analyzes the macroeconomic effects of limiting China's CO2 emissions by using a time-recursive dynamic computable general equilibrium (CGE) model of the Chinese economy. The baseline scenario for the Chinese economy over the period to 2010 is first developed under a set of assumptions abou

  3. Funded pensions and intergenerational and international risk sharing in general equilibrium

    NARCIS (Netherlands)

    Beetsma, R.M.W.J.; Bovenberg, A.L.; Romp, W.E.

    2011-01-01

    We explore intergenerational and international risk sharing in a general equilibrium multiple-country model with two-tier pensions systems. The exact design of the pension system is key for the way in which risks are shared over generations. The laissez-faire market solution fails to provide an opti

  4. Computer Assisted Instruction in Economics: An Approach for Illustrating General Equilibrium Concepts.

    Science.gov (United States)

    Gillespie, Robert W.

    A market exchange simulation utilizing the PLATO computer-assisted instructional system at the University of Illinois has been designed to teach students the principles of a general equilibrium system. It serves a laboratory function which supplements traditional instruction by stimulating students' interests and providing them with illustrations…

  5. Convergence of Iterative Sequences for Generalized Equilibrium Problems Involving Inverse-Strongly Monotone Mappings

    Directory of Open Access Journals (Sweden)

    Cho SunYoung

    2010-01-01

    Full Text Available Abstract The purpose of this paper is to consider the weak convergence of an iterative sequence for finding a common element in the set of solutions of generalized equilibrium problems, in the set of solutions of classical variational inequalities, and in the set of fixed points of nonexpansive mappings.

  6. R&D and economic growth in Slovenia: A dynamic general equilibrium approach with endogenous growth

    NARCIS (Netherlands)

    Verbic, M.; Majcen, B.; Ivanova, O.; Cok, M.

    2011-01-01

    In the article, we model R&D as a major endogenous growth element in a small open economy general equilibrium framework and consider several R&D policy scenarios for Slovenia. Increase of the share of sectoral investment in R&D that is deductible from the corporate income tax and increase of governm

  7. General and Partial Equilibrium Modeling of Sectoral Policies to Address Climate Change in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Pizer, William; Burtraw, Dallas; Harrington, Winston; Newell, Richard; Sanchirico, James; Toman, Michael

    2003-03-31

    This document provides technical documentation for work using detailed sectoral models to calibrate a general equilibrium analysis of market and non-market sectoral policies to address climate change. Results of this work can be found in the companion paper, "Modeling Costs of Economy-wide versus Sectoral Climate Policies Using Combined Aggregate-Sectoral Model".

  8. Performing an Environmental Tax Reform in a regional Economy. A Computable General Equilibrium

    NARCIS (Netherlands)

    Andre, F.J.; Cardenete, M.A.; Velazquez, E.

    2003-01-01

    We use a Computable General Equilibrium model to simulate the effects of an Environmental Tax Reform in a regional economy (Andalusia, Spain).The reform involves imposing a tax on CO2 or SO2 emissions and reducing either the Income Tax or the payroll tax of employers to Social Security, and eventual

  9. Frictions, Persistence, and Central Bank Policy in an Experimental Dynamic Stochastic General Equilibrium Economy

    NARCIS (Netherlands)

    Noussair, C.N.; Pfajfar, D.; Zsiros, J.

    2011-01-01

    New Keynesian dynamic stochastic general equilibrium models are the principal paradigm currently employed for central bank policymaking. In this paper, we construct experimental economies, populated with human subjects, with the structure of a New Keynesian DSGE model. We give individuals monetary i

  10. The economic impact of water tax charges in China: a static computable general equilibrium analysis.

    NARCIS (Netherlands)

    Qin, C.; Jia, Y.; Su, Z.; Bressers, J.T.A.; Wanga, H.

    2012-01-01

    This paper presents a static computable general equilibrium model of the Chinese economy with water as an explicit factor of production. This model is used to assess the broad economic impact of a policy based on water demand management, using water tax charges as a policy-setting tool. It suggests

  11. General relativistic model for experimental measurement of the speed of propagation of gravity by VLBI

    CERN Document Server

    Kopeikin, S M; Kopeikin, Sergei; Fomalont, Ed

    2002-01-01

    A relativistic sub-picosecond model of gravitational time delay in radio astronomical observations is worked out and a new experimental test of general relativity is discussed in which the effect of retardation of gravity associated with its finite speed can be observed. As a consequence, the speed of gravity can be measured by differential VLBI observations. Retardation in propagation of gravity is a central part of the Einstein theory of general relativity which has not been tested directly so far. The idea of the proposed gravitational experiment is based on the fact that gravity in general relativity propagates with finite speed so that the deflection of light caused by the body must be sensitive to the ratio of the body's velocity to the speed of gravity. The interferometric experiment can be performed, for example, during the very close angular passage of a quasar by Jupiter. Due to the finite speed of gravity and orbital motion of Jupiter, the variation in its gravitational field reaches observer on Ea...

  12. Critical rotation of general-relativistic polytropic models simulating neutron stars: a post-Newtonian hybrid approximative scheme

    CERN Document Server

    Geroyannis, Vassilis S

    2014-01-01

    We develop a "hybrid approximative scheme" in the framework of the post-Newtonian approximation for computing general-relativistic polytropic models simulating neutron stars in critical rigid rotation. We treat the differential equations governing such a model as a "complex initial value problem", and we solve it by using the so-called "complex-plane strategy". We incorporate into the computations the complete solution for the relativistic effects, this issue representing a significant improvement with regard to the classical post-Newtonian approximation, as verified by extended comparisons of the numerical results.

  13. Relativistic thermodynamics, a Lagrangian field theory for general flows including rotation

    Science.gov (United States)

    Frønsdal, Christian

    Any theory that is based on an action principle has a much greater predictive power than one that does not have such a formulation. The formulation of a dynamical theory of General Relativity, including matter, is here viewed as a problem of coupling Einstein’s theory of pure gravity to an independently chosen and well-defined field theory of matter. It is well known that this is accomplished in a most natural way when both theories are formulated as relativistic, Lagrangian field theories, as is the case with Einstein-Maxwell theory. Special matter models of this type have been available; here a more general thermodynamical model that allows for vortex flows is presented. In a wider context, the problem of subjecting hydrodynamics and thermodynamics to an action principle is one that has been pursued for at least 150 years. A solution to this problem has been known for some time, but only under the strong restriction to potential flows. A variational principle for general flows has become available. It represents a development of the Navier-Stokes-Fourier approach to fluid dynamics. The principal innovation is the recognition that two kinds of flow velocity fields are needed, one the gradient of a scalar field and the other the time derivative of a vector field, the latter closely associated with vorticity. In the relativistic theory that is presented here, the latter is the Hodge dual of an exact 3-form, well known as the notoph field of Ogievetskij and Palubarinov, the B-field of Kalb and Ramond and the vorticity field of Lund and Regge. The total number of degrees of freedom of a unary system, including the density and the two velocity fields is 4, as expected — as in classical hydrodynamics. In this paper, we do not reduce Einstein’s dynamical equation for the metric to phenomenology, which would have denied the relevance of any intrinsic dynamics for the matter sector, nor do we abandon the equation of continuity - the very soul of hydrodynamics.

  14. Effects of anisotropy on gravitational infall in galaxy clusters using an exact general relativistic model

    CERN Document Server

    Troxel, M A; Ishak, Mustapha

    2013-01-01

    We study the effects and implications of anisotropies at the scale of galaxy clusters by building an exact general relativistic model of a cluster using the inhomogeneous and anisotropic Szekeres metric. The model is built from a modified Navarro-Frenk-White (NFW) density profile. We compare this to a corresponding spherically symmetric structure in the Lemaitre-Tolman (LT) model and quantify the impact of introducing varying levels of anisotropy. We examine two physical measures of gravitational infall -- the growth rate of density and the velocity of the source dust in the model. We introduce a generalization of the LT dust velocity profile for the Szekeres metric and demonstrate its consistency with the growth rate of density. We find that the growth rate of density in one substructure increases by 0.5%, 1.5%, and 3.75% for 5%, 10%, and 15% levels of introduced anisotropy, which is measured as the fractional displaced mass relative to the spherically symmetric case. The infall velocity of the dust is found...

  15. Generalized Lagrangian-Path Representation of Non-Relativistic Quantum Mechanics

    Science.gov (United States)

    Tessarotto, Massimo; Cremaschini, Claudio

    2016-08-01

    In this paper a new trajectory-based representation to non-relativistic quantum mechanics is formulated. This is ahieved by generalizing the notion of Lagrangian path (LP) which lies at the heart of the deBroglie-Bohm " pilot-wave" interpretation. In particular, it is shown that each LP can be replaced with a statistical ensemble formed by an infinite family of stochastic curves, referred to as generalized Lagrangian paths (GLP). This permits the introduction of a new parametric representation of the Schrödinger equation, denoted as GLP-parametrization, and of the associated quantum hydrodynamic equations. The remarkable aspect of the GLP approach presented here is that it realizes at the same time also a new solution method for the N-body Schrödinger equation. As an application, Gaussian-like particular solutions for the quantum probability density function (PDF) are considered, which are proved to be dynamically consistent. For them, the Schrödinger equation is reduced to a single Hamilton-Jacobi evolution equation. Particular solutions of this type are explicitly constructed, which include the case of free particles occurring in 1- or N-body quantum systems as well as the dynamics in the presence of suitable potential forces. In all these cases the initial Gaussian PDFs are shown to be free of the spreading behavior usually ascribed to quantum wave-packets, in that they exhibit the characteristic feature of remaining at all times spatially-localized.

  16. Satisfaction Equilibrium: A General Framework for QoS Provisioning in Self-Configuring Networks

    CERN Document Server

    Perlaza, Samir M; Lasaulce, Samson; Debbah, Merouane

    2010-01-01

    This paper is concerned with the concept of equilibrium and quality of service (QoS) provisioning in self-configuring wireless networks with non-cooperative radio devices (RD). In contrast with the Nash equilibrium (NE), where RDs are interested in selfishly maximizing its QoS, we present a concept of equilibrium, named satisfaction equilibrium (SE), where RDs are interested only in guaranteing a minimum QoS. We provide the conditions for the existence and the uniqueness of the SE. Later, in order to provide an equilibrium selection framework for the SE, we introduce the concept of effort or cost of satisfaction, for instance, in terms of transmit power levels, constellation sizes, etc. Using the idea of effort, the set of efficient SE (ESE) is defined. At the ESE, transmitters satisfy their minimum QoS incurring in the lowest effort. We prove that contrary to the (generalized) NE, at least one ESE always exists whenever the network is able to simultaneously support the individual QoS requests. Finally, we pr...

  17. A NEW MULTI-DIMENSIONAL GENERAL RELATIVISTIC NEUTRINO HYDRODYNAMICS CODE FOR CORE-COLLAPSE SUPERNOVAE. II. RELATIVISTIC EXPLOSION MODELS OF CORE-COLLAPSE SUPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Bernhard; Janka, Hans-Thomas; Marek, Andreas, E-mail: bjmuellr@mpa-garching.mpg.de, E-mail: thj@mpa-garching.mpg.de [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)

    2012-09-01

    We present the first two-dimensional general relativistic (GR) simulations of stellar core collapse and explosion with the COCONUT hydrodynamics code in combination with the VERTEX solver for energy-dependent, three-flavor neutrino transport, using the extended conformal flatness condition for approximating the space-time metric and a ray-by-ray-plus ansatz to tackle the multi-dimensionality of the transport. For both of the investigated 11.2 and 15 M{sub Sun} progenitors we obtain successful, though seemingly marginal, neutrino-driven supernova explosions. This outcome and the time evolution of the models basically agree with results previously obtained with the PROMETHEUS hydro solver including an approximative treatment of relativistic effects by a modified Newtonian potential. However, GR models exhibit subtle differences in the neutrinospheric conditions compared with Newtonian and pseudo-Newtonian simulations. These differences lead to significantly higher luminosities and mean energies of the radiated electron neutrinos and antineutrinos and therefore to larger energy-deposition rates and heating efficiencies in the gain layer with favorable consequences for strong nonradial mass motions and ultimately for an explosion. Moreover, energy transfer to the stellar medium around the neutrinospheres through nucleon recoil in scattering reactions of heavy-lepton neutrinos also enhances the mentioned effects. Together with previous pseudo-Newtonian models, the presented relativistic calculations suggest that the treatment of gravity and energy-exchanging neutrino interactions can make differences of even 50%-100% in some quantities and is likely to contribute to a finally successful explosion mechanism on no minor level than hydrodynamical differences between different dimensions.

  18. Relativistic point dynamics general equations, constant proper masses, interactions between electric charges, variable proper masses, collisions

    CERN Document Server

    Arzeliès, Henri

    1972-01-01

    Relativistic Point Dynamics focuses on the principles of relativistic dynamics. The book first discusses fundamental equations. The impulse postulate and its consequences and the kinetic energy theorem are then explained. The text also touches on the transformation of main quantities and relativistic decomposition of force, and then discusses fields of force derivable from scalar potentials; fields of force derivable from a scalar potential and a vector potential; and equations of motion. Other concerns include equations for fields; transfer of the equations obtained by variational methods int

  19. General-relativistic electromagnetic fields around a slowly rotating neutron star: time-dependent pseudo-spectral simulations

    CERN Document Server

    Pétri, J

    2014-01-01

    Pulsars are believed to loose their rotational kinetic energy primarily by a large amplitude low frequency electromagnetic wave which is eventually converted into particle creation, acceleration and followed by a broad band radiation spectrum. To date, there exist no detailed calculation of the exact spin-down luminosity with respect to the neutron star magnetic moment and spin frequency, including general-relativistic effects. Estimates are usually given according to the flat spacetime magnetodipole formula. The present paper pursue our effort to look for accurate solutions of the general-relativistic electromagnetic field around a slowly rotating magnetized neutron star. In a previous work, we already found approximate stationary solutions to this problem. Here we address again this problem but using a more general approach. We indeed solve the full set of time-dependent Maxwell equations in a curved vacuum space-time following the 3+1 formalism. The numerical code is based on our pseudo-spectral method exp...

  20. General relativistic radiation hydrodynamics of accretion flows: II. Treating stiff source terms and exploring physical limitations

    CERN Document Server

    Roedig, Constanze; Alic, Daniela

    2012-01-01

    We present the implementation of an implicit-explicit (IMEX) Runge-Kutta numerical scheme for general relativistic hydrodynamics coupled to an optically thick radiation field in two existing GR-hydrodynamics codes. We argue that the necessity of such an improvement arises naturally in astrophysically relevant regimes where the optical thickness is high as the equations become stiff. By performing several 1D tests we verify the codes' new ability to deal with this stiffness and show consistency. Then, still in 1D, we compute a luminosity versus accretion rate diagram for the setup of spherical accretion onto a Schwarzschild black hole and find good agreement with previous work. Lastly, we revisit the supersonic Bondi Hoyle Lyttleton (BHL) accretion in 2D where we can now present simulations of realistic temperatures, down to T~10^6 K. Here we find that radiation pressure plays an important role, but also that these highly dynamical set-ups push our approximate treatment towards the limit of physical applicabil...

  1. High-Order Fully General-Relativistic Hydrodynamics: new Approaches and Tests

    CERN Document Server

    Radice, David; Galeazzi, Filippo

    2013-01-01

    We present a new approach for achieving high-order convergence in fully general-relativistic hydrodynamic simulations. The approach is implemented in WhiskyTHC, a new code that makes use of state-of-the-art numerical schemes and was key in achieving, for the first time, higher than second-order convergence in the calculation of the gravitational radiation from inspiraling binary neutron stars Radice et al. (2013). Here, we give a detailed description of the algorithms employed and present results obtained for a series of classical tests involving isolated neutron stars. In addition, using the gravitational-wave emission from the late inspiral and merger of binary neutron stars, we make a detailed comparison between the results obtained with the new code and those obtained when using standard second-order schemes commonly employed for matter simulations in numerical relativity. We find that even at moderate resolutions and for binaries with large compactness, the phase accuracy is improved by a factor 50 or mo...

  2. General relativistic magnetohydrodynamic simulations of binary neutron star mergers with the APR4 equation of state

    Science.gov (United States)

    Endrizzi, A.; Ciolfi, R.; Giacomazzo, B.; Kastaun, W.; Kawamura, T.

    2016-08-01

    We present new results of fully general relativistic magnetohydrodynamic simulations of binary neutron star (BNS) mergers performed with the Whisky code. All the models use a piecewise polytropic approximation of the APR4 equation of state for cold matter, together with a ‘hybrid’ part to incorporate thermal effects during the evolution. We consider both equal and unequal-mass models, with total masses such that either a supramassive NS or a black hole is formed after merger. Each model is evolved with and without a magnetic field initially confined to the stellar interior. We present the different gravitational wave (GW) signals as well as a detailed description of the matter dynamics (magnetic field evolution, ejected mass, post-merger remnant/disk properties). Our simulations provide new insights into BNS mergers, the associated GW emission and the possible connection with the engine of short gamma-ray bursts (both in the ‘standard’ and in the ‘time-reversal’ scenarios) and other electromagnetic counterparts.

  3. General Relativistic Magnetohydrodynamic Simulations of Binary Neutron Star Mergers with the APR4 Equation of State

    CERN Document Server

    Endrizzi, Andrea; Giacomazzo, Bruno; Kastaun, Wolfgang; Kawamura, Takumu

    2016-01-01

    We present new results of fully general relativistic magnetohydrodynamic (GRMHD) simulations of binary neutron star (BNS) mergers performed with the Whisky code. All the models use a piecewise polytropic approximation of the APR4 equation of state (EOS) for cold matter, together with a "hybrid" part to incorporate thermal effects during the evolution. We consider both equal and unequal-mass models, with total masses such that either a supramassive NS or a black hole (BH) is formed after merger. Each model is evolved with and without a magnetic field initially confined to the stellar interior. We present the different gravitational wave (GW) signals as well as a detailed description of the matter dynamics (magnetic field evolution, ejected mass, post-merger remnant/disk properties). Our simulations provide new insights into BNS mergers, the associated GW emission and the possible connection with the engine of short gamma-ray bursts (both in the "standard" and in the "time-reversal" scenarios) and other electro...

  4. The general relativistic instability supernova of a supermassive population III star

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ke-Jung; Woosley, Stan [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Heger, Alexander [Monash Centre for Astrophysics, Monash University, Victoria 3800 (Australia); Almgren, Ann [Center for Computational Sciences and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Whalen, Daniel J. [T-2, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Johnson, Jarrett L., E-mail: kchen@ucolick.org [XTD-PRI, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2014-08-01

    The formation of supermassive Population III stars with masses ≳10,000 M{sub ☉} in primeval galaxies in strong ultraviolet backgrounds at z ∼ 15 may be the most viable pathway to the formation of supermassive black holes by z ∼ 7. Most of these stars are expected to live for short times and then directly collapse to black holes, with little or no mass loss over their lives. However, we have now discovered that non-rotating primordial stars with masses close to 55,000 M{sub ☉} can instead die as highly energetic thermonuclear supernovae powered by explosive helium burning, releasing up to 10{sup 55} erg, or about 10,000 times the energy of a Type Ia supernova. The explosion is triggered by the general relativistic contribution of thermal photons to gravity in the core of the star, which causes the core to contract and explosively burn. The energy release completely unbinds the star, leaving no compact remnant, and about half of the mass of the star is ejected into the early cosmos in the form of heavy elements. The explosion would be visible in the near infrared at z ≲ 20 to Euclid and the Wide-Field Infrared Survey Telescope, perhaps signaling the birth of supermassive black hole seeds and the first quasars.

  5. Odyssey: A Public GPU-Based Code for General-Relativistic Radiative Transfer in Kerr Spacetime

    CERN Document Server

    Pu, Hung-Yi; Younsi, Ziri; Yoon, Suk-Jin

    2016-01-01

    General-relativistic radiative transfer (GRRT) calculations coupled with the calculation of geodesics in the Kerr spacetime are an essential tool for determining the images, spectra and light curves from matter in the vicinity of black holes. Such studies are especially important for ongoing and upcoming millimeter/submillimeter (mm/sub-mm) Very Long Baseline Interferometry (VLBI) observations of the supermassive black holes at the centres of Sgr A^{*} and M87. To this end we introduce Odyssey, a Graphics Processing Unit(GPU)-based code for ray tracing and radiative transfer in the Kerr spacetime. On a single GPU, the performance of Odyssey can exceed 1 nanosecond per photon, per Runge-Kutta integration step. Odyssey is publicly available, fast, accurate, and flexible enough to be modified to suit the specific needs of new users. Along with a Graphical User Interface (GUI) powered by a video-accelerated display architecture, we also present an educational software tool, Odyssey_Edu, for showing in real time h...

  6. Odyssey: A Public GPU-based Code for General Relativistic Radiative Transfer in Kerr Spacetime

    Science.gov (United States)

    Pu, Hung-Yi; Yun, Kiyun; Younsi, Ziri; Yoon, Suk-Jin

    2016-04-01

    General relativistic radiative transfer calculations coupled with the calculation of geodesics in the Kerr spacetime are an essential tool for determining the images, spectra, and light curves from matter in the vicinity of black holes. Such studies are especially important for ongoing and upcoming millimeter/submillimeter very long baseline interferometry observations of the supermassive black holes at the centers of Sgr A* and M87. To this end we introduce Odyssey, a graphics processing unit (GPU) based code for ray tracing and radiative transfer in the Kerr spacetime. On a single GPU, the performance of Odyssey can exceed 1 ns per photon, per Runge-Kutta integration step. Odyssey is publicly available, fast, accurate, and flexible enough to be modified to suit the specific needs of new users. Along with a Graphical User Interface powered by a video-accelerated display architecture, we also present an educational software tool, Odyssey_Edu, for showing in real time how null geodesics around a Kerr black hole vary as a function of black hole spin and angle of incidence onto the black hole.

  7. General-Relativistic Simulations of Three-Dimensional Core-Collapse Supernovae

    CERN Document Server

    Ott, C D; Moesta, P; Haas, R; Drasco, S; O'Connor, E; Reisswig, C; Meakin, C; Schnetter, E

    2012-01-01

    We study the three-dimensional (3D) hydrodynamics of the post-core-bounce phase of the collapse of a 27 solar-mass star and pay special attention to the development of the standing accretion shock instability (SASI) and neutrino-driven convection. To this end, we perform 3D general-relativistic simulations with a 3-species neutrino leakage scheme with neutrino heating. Unlike "light-bulb" heating/cooling schemes, the leakage scheme captures the essential aspects of neutrino cooling, heating, and lepton number exchange as predicted by radiation-hydrodynamics simulations. The 27 solar-mass progenitor was studied in 2D by B. Mueller et al. (2012; arXiv:1205.7078), who observed strong growth of the SASI while neutrino-driven convection was suppressed. In our 3D simulations, neutrino-driven convection grows from numerical perturbations imposed by our Cartesian grid. It becomes the dominant instability and leads to large-scale non-oscillatory deformations of the shock front. These will result in strongly aspherical...

  8. General relativistic modelling of the negative reverberation X-ray time delays in AGN

    CERN Document Server

    Emmanoulopoulos, D; Dovciak, M; McHardy, I M

    2014-01-01

    We present the first systematic physical modelling of the time-lag spectra between the soft (0.3-1 keV) and the hard (1.5-4 keV) X-ray energy bands, as a function of Fourier frequency, in a sample of 12 active galactic nuclei which have been observed by XMM-Newton. We concentrate particularly on the negative X-ray time-lags (typically seen above $10^{-4}$ Hz) i.e. soft band variations lag the hard band variations, and we assume that they are produced by reprocessing and reflection by the accretion disc within a lamp-post X-ray source geometry. We also assume that the response of the accretion disc, in the soft X-ray bands, is adequately described by the response in the neutral iron line (Fe k$\\alpha$) at 6.4 keV for which we use fully general relativistic ray-tracing simulations to determine its time evolution. These response functions, and thus the corresponding time-lag spectra, yield much more realistic results than the commonly-used, but erroneous, top-hat models. Additionally we parametrize the positive ...

  9. General Relativistic Magnetohydrodynamic Simulations of Blandford-Znajek Jets and the Membrane Paradigm

    CERN Document Server

    Penna, Robert F; Sadowski, Aleksander

    2013-01-01

    Recently it has been observed that the scaling of jet power with black hole spin in galactic X-ray binaries is consistent with the predictions of the Blandford-Znajek (BZ) jet model. These observations motivate us to revisit the BZ model using general relativistic magnetohydrodynamic simulations of magnetized jets from accreting (h/r ~ 0.3), spinning (0 < a_* < 0.98) black holes. We have three main results. First, we quantify the discrepancies between the BZ jet power and our simulations: assuming maximum efficiency and uniform fields on the horizon leads to a ~10% overestimate of jet power, while ignoring the accretion disk leads to a further ~50% overestimate. Simply reducing the standard BZ jet power prediction by 60% gives a good fit to our simulation data. Our second result is to show that the membrane formulation of the BZ model correctly describes the physics underlying simulated jets: torques, dissipation, and electromagnetic fields on the horizon. This provides intuitive yet rigorous pictures f...

  10. A General Relativistic Magnetohydrodynamics Simulation of Jet Formation with a State Transition

    Science.gov (United States)

    Nishikawa, K. I.; Richardson, G.; Koide, S.; Shibata, K.; Kudoh, T.; Hardee, P.; Fushman, G. J.

    2004-01-01

    We have performed the first fully three-dimensional general relativistic magnetohydrodynamic (GRMHD) simulation of jet formation from a thin accretion disk around a Schwarzschild black hole with a free-falling corona. The initial simulation results show that a bipolar jet (velocity sim 0.3c) is created as shown by previous two-dimensional axisymmetric simulations with mirror symmetry at the equator. The 3-D simulation ran over one hundred light-crossing time units which is considerably longer than the previous simulations. We show that the jet is initially formed as predicted due in part to magnetic pressure from the twisting the initially uniform magnetic field and from gas pressure associated with shock formation. At later times, the accretion disk becomes thick and the jet fades resulting in a wind that is ejected from the surface of the thickened (torus-like) disk. It should be noted that no streaming matter from a donor is included at the outer boundary in the simulation (an isolated black hole not binary black hole). The wind flows outwards with a wider angle than the initial jet. The widening of the jet is consistent with the outward moving shock wave. This evolution of jet-disk coupling suggests that the low/hard state of the jet system may switch to the high/soft state with a wind, as the accretion rate diminishes.

  11. Pinpointing the base of the AGN jets through general relativistic X-ray reverberation studies

    CERN Document Server

    Emmanoulopoulos, D

    2014-01-01

    Many theoretical models of Active Galactic Nuclei (AGN) predict that the X-ray corona, lying above the black hole, constitutes the base of the X-ray jet. Thus, by studying the exact geometry of the close black hole environment, we can pinpoint the launching site of the jet. Detection of negative X-ray reverberation time delays (i.e. soft band X-ray variations lagging behind the corresponding hard band X-ray variations) can yield significant information about the geometrical properties of the AGN, such as the location of the X-ray source, as well as the physical properties of the the black hole, such as its mass and spin. In the frame-work of the lamp-post geometry, I present the first systematic X-ray time-lag modelling results of an ensemble of 12 AGN, using a fully general relativistic (GR) ray tracing approach for the estimation of the systems' response functions. By combing these state-of-the art GR response models with statistically innovative fitting routines, I derive the geometrical layout of the clos...

  12. Relativistic Fluid Dynamics

    CERN Document Server

    Cattaneo, Carlo

    2011-01-01

    This title includes: Pham Mau Quam: Problemes mathematiques en hydrodynamique relativiste; A. Lichnerowicz: Ondes de choc, ondes infinitesimales et rayons en hydrodynamique et magnetohydrodynamique relativistes; A.H. Taub: Variational principles in general relativity; J. Ehlers: General relativistic kinetic theory of gases; K. Marathe: Abstract Minkowski spaces as fibre bundles; and, G. Boillat: Sur la propagation de la chaleur en relativite.

  13. OSCILLATIONS IN THE WALRASIAN GENERAL EQUILIBRIUM THEORY WITH ENDOGENOUS WEALTH AND HUMAN CAPITAL ACCUMULATION

    Directory of Open Access Journals (Sweden)

    Wei Bin ZHANG

    2016-02-01

    Full Text Available This paper generalizes the dynamic growth model with wealth accumulation and human capital accumulation proposed by Zhang (2013 by making all the parameters as time-dependent parameters. The original model is an extension of the Uzawa-Lucas model to a heterogeneous household economy with multiple ways of human capital accumulation. It synthesizes the basic ideas of the Walrasian general equilibrium theory, Arrow’s learning by producing, Zhang’s learning by consuming (creative learning, the neoclassical growth theory, and the Uzawa-Lucas two-sector model. The behavior of the household is described with an alternative approach to household behavior. The economic system consists of one production sector and one education sector. Households are different in propensities to save, to obtain education and to consume, and in learning abilities. We simulate the model to demonstrate existence of equilibrium points, motion of the dynamic system, and oscillations due to different exogenous shocks. 

  14. Climate Change and Economic Growth: An Intertemporal General Equilibrium Analysis for Egypt

    OpenAIRE

    Elshennawy, Abeer; Robinson, Sherman; Willenbockel, Dirk

    2013-01-01

    Due to the high concentration of economic activity along the low-lying coastal zone of the Nile delta and its dependence on Nile river streamflow, Egypt's economy is highly exposed to adverse climate change. Adaptation planning requires a forward-looking assessment of climate change impacts on economic performance at economy-wide and sectoral level and a cost-benefit assessment of conceivable adaptation investments. This study develops a multisectoral intertemporal general equilibrium model w...

  15. THE ECONOMIC IMPACT OF RESTRICTED WATER SUPPLY: A COMPUTABLE GENERAL EQUILIBRIUM ANALYSIS

    OpenAIRE

    Maria Berrittella; Katrin Rehdanz; Hoekstra, Arjen Y.; Roberto Roson; Tol, Richard S J

    2006-01-01

    Water problems are typically studied at the level of the river catchment. About 70% of all water is used for agriculture, and agricultural products are traded internationally. A full understanding of water use is impossible without understanding the international market for food and related products, such as textiles. The water embedded in commodities is called virtual water. Based on a general equilibrium model, we offer a method for investigating the role of water resources and water scarci...

  16. Iterative Schemes for Generalized Equilibrium Problem and Two Maximal Monotone Operators

    Directory of Open Access Journals (Sweden)

    Yao JC

    2009-01-01

    Full Text Available The purpose of this paper is to introduce and study two new hybrid proximal-point algorithms for finding a common element of the set of solutions to a generalized equilibrium problem and the sets of zeros of two maximal monotone operators in a uniformly smooth and uniformly convex Banach space. We established strong and weak convergence theorems for these two modified hybrid proximal-point algorithms, respectively.

  17. International factor mobility, informal interest rate and capital market imperfection: a general equilibrium analysis

    OpenAIRE

    Chaudhuri, Sarbajit; GUPTA, Manash Ranjan

    2011-01-01

    This paper makes a pioneering attempt to provide a theory of determination of interest rate in the informal credit market in a small open economy in terms of a three-sector general equilibrium model. There are two informal sectors which obtain production loans from a monopolistic moneylender and employ labour from the informal labour market. On the other hand, the formal sector employs labour at an institutionally fixed wage rate and takes loans from the competitive formal credit market. We s...

  18. The economic impact of uncertain tourism demand in Hawaii: risk in a computable general equilibrium model

    OpenAIRE

    2009-01-01

    This thesis estimates the economic impact of uncertain tourism demand in Hawaii. It does this by incorporating risk into a Computable General Equilibrium (CGE) model. CGE models have been used to investigate a wide range of policy issues. To date, none have investigated how uncertainty regarding future tourism demand impacts on an economy. The context in which this research is set is the US State of Hawaii. The economy of Hawaii is heavily dependent on tourism as a source of income and a...

  19. Globalization and the Polish economy: stylized facts and simulations using a Computable General Equilibrium Model

    OpenAIRE

    Gradzewicz, Michał; Hagemejer, Jan; Zbigniew, Żółkiewski

    2007-01-01

    The aim of the paper is to quantitatively assess the impact of globalization on the economy of Poland in the medium term. Four channels of the impact of globalization are distinguished: (i) trade openness, (ii) productivity improvement, (iii) labour migrations, (iv) liberalization of the services sector. We employ a computable general equilibrium model with multiple industries and households and imperfect competition features. Our results show positive and quite significant effects of globali...

  20. Entropy production in non-equilibrium systems described by the generalized Langevin equation

    Science.gov (United States)

    Sevilla, Francisco J.; Piña-Perez, Omar

    2014-03-01

    The generalized Langevin equation for a charged particle under the influence of time-dependent external fields, is employed to study the effects of non-Markovian dissipative terms in the entropy production of non-equilibrium states exhibiting non-zero mass flux. We present results for the case in which the fluctuation-dissipation relation holds. FJS and OPP acknowledge financial support from PAPIIT-IN113114 and PAEP-UNAM respectively.

  1. THE EONOMIC IMPACT OF MORE SUSTAINABLE WATER USE IN AGRICULTURE: A COMPUTABLE GENERAL EQUILIBRIUM ANALYSIS

    OpenAIRE

    Alvaro Calzadilla; Katrin Rehdanz; Richard S.J. Tol

    2008-01-01

    Water problems are typically studied at the farm-level, the river–catchment-level or the country-level. About 70% of irrigation water is used for agriculture, and agricultural products are traded internationally. A full understanding of water use is impossible without understanding the international market for food and related products, such as textiles. Based on the global general equilibrium model GTAP-W, we offer a method for investigating the role of green (rain) and blue (irrigation) wat...

  2. Relativistic self-similar dynamic gravitational collapses of a quasi-spherical general polytropic magnetofluid

    Science.gov (United States)

    Lou, Yu-Qing; Xia, Yu-Kai

    2017-05-01

    We study magnetohydrodynamic (MHD) self-similar collapses and void evolution, with or without shocks, of a general polytropic quasi-spherical magnetofluid permeated by random transverse magnetic fields under the Paczynski-Wiita gravity that captures essential general relativistic effects of a Schwarzschild black hole (BH) with a growing mass. Based on the derived set of non-linear MHD ordinary differential equations, we obtain various asymptotic MHD solutions, the geometric and analytical properties of the magnetosonic critical curve (MSCC) and MHD shock jump conditions. Novel asymptotic MHD solution behaviours near the rim of central expanding voids are derived analytically. By exploring numerical global MHD solutions, we identify allowable boundary conditions at large radii that accommodate a smooth solution and show that a reasonable amount of magnetization significantly increases the mass accretion rate in the expansion-wave-collapse solution scenario. We also construct the counterparts of envelope-expansion-core-collapse solutions that cross the MSCC twice, which are found to be closely paired with a sequence of global smooth solutions satisfying a novel type of central MHD behaviours. MHD shocks with static outer and various inner flow profiles are also examined. Astrophysical applications include dynamic core collapses of magnetized massive stars and compact objects as well as formation of supermassive, hypermassive, dark matter and mixed matter BHs in the Universe, including the early Universe. Such gigantic BHs can be detected in X-ray/gamma-ray sources, quasars, ultraluminous infrared galaxies or extremely luminous infrared galaxies and dark matter overwhelmingly dominated elliptical galaxies as well as massive dark matter halos, etc. Gravitational waves and electromagnetic wave emissions in broad band (including e.g., gamma-ray bursts and fast radio bursts) can result from this type of dynamic collapses of forming BHs involving magnetized media.

  3. SIMULASI PENGELUARAN PEMERINTAH DAN DAMPAKNYA TERHADAP KINERJAEKONOMI MAKRO: SUATU MODEL COMPUTABLE GENERAL EQUILIBRIUM

    Directory of Open Access Journals (Sweden)

    Indra Maipita

    2012-06-01

    Full Text Available This study analyzes the impact of increased government spending on macroeconomic performance, using AGEFIS; a Computable General Equilibrium Model. Simulations carried out with the three scenarios in the sector Construction, Electricity, and Land Transportation. The simulation results shows that, in general, an increase in government spending have a positive impact on macroeconomic performance and increase household income. increase in government spending in the Construction sector provides better impact on increasing household income compared with other sectors, while in the electricity sector have no effect

  4. The Bargmann type reduction for some Lax integrable two-dimensional generalization of the relativistic Toda lattice

    Directory of Open Access Journals (Sweden)

    O. Ye. Hentosh

    2016-01-01

    Full Text Available The possibility of applying the method of reducing upon finite-dimensional invariant subspaces, generated by the eigenvalues of the associated spectral problem, to some two-dimensional generalization of the relativistic Toda lattice with the triple matrix Lax type linearization is investigated. The Hamiltonian property and Lax-Liouville integrability of the vector fields, given by this system, on the invariant subspace related with the Bargmann type reduction are found out.

  5. Non-relativistic pair annihilation of nearly mass degenerate neutralinos and charginos I. General framework and S-wave annihilation

    OpenAIRE

    Beneke, M.; Hellmann, C.; Ruiz-Femenia, P.

    2012-01-01

    We compute analytically the tree-level annihilation rates of a collection of non-relativistic neutralino and chargino two-particle states in the general MSSM, including the previously unknown off-diagonal rates. The results are prerequisites to the calculation of the Sommerfeld enhancement in the MSSM, which will be presented in subsequent work. They can also be used to obtain concise analytic expressions for MSSM dark matter pair annihilation in the present Universe for a large number of exc...

  6. Exact power series solutions of the structure equations of the general relativistic isotropic fluid stars with linear barotropic and polytropic equations of state

    CERN Document Server

    Harko, T

    2016-01-01

    Obtaining exact solutions of the spherically symmetric general relativistic gravitational field equations describing the interior structure of an isotropic fluid sphere is a long standing problem in theoretical and mathematical physics. The usual approach to this problem consists mainly in the numerical investigation of the Tolman-Oppenheimer-Volkoff and of the mass continuity equations, which describes the hydrostatic stability of the dense stars. In the present paper we introduce an alternative approach for the study of the relativistic fluid sphere, based on the relativistic mass equation, obtained by eliminating the energy density in the Tolman-Oppenheimer-Volkoff equation. Despite its apparent complexity, the relativistic mass equation can be solved exactly by using a power series representation for the mass, and the Cauchy convolution for infinite power series. We obtain exact series solutions for general relativistic dense astrophysical objects described by the linear barotropic and the polytropic equa...

  7. Thermodynamic equilibrium in relativity: four-temperature, Killing vectors and Lie derivatives

    CERN Document Server

    Becattini, F

    2016-01-01

    The main concepts of general relativistic thermodynamics and general relativistic statistical mechanics are reviewed. The main building block of the proper relativistic extension of the classical thermodynamics laws is the four-temperature vector \\beta, which plays a major role in the quantum framework and defines a very convenient hydrodynamic frame. The general relativistic thermodynamic equilibrium condition demands \\beta to be a Killing vector field. We show that a remarkable consequence is that all Lie derivatives of all physical observables along the four-temperature flow must then vanish.

  8. General relativistic modelling of the negative reverberation X-ray time delays in AGN

    Science.gov (United States)

    Emmanoulopoulos, D.; Papadakis, I. E.; Dovčiak, M.; McHardy, I. M.

    2014-04-01

    We present the first systematic physical modelling of the time-lag spectra between the soft (0.3-1 keV) and the hard (1.5-4 keV) X-ray energy bands, as a function of Fourier frequency, in a sample of 12 active galactic nuclei which have been observed by XMM-Newton. We concentrate particularly on the negative X-ray time-lags (typically seen above 10-4 Hz), i.e. soft-band variations lag the hard-band variations, and we assume that they are produced by reprocessing and reflection by the accretion disc within a lamp-post X-ray source geometry. We also assume that the response of the accretion disc, in the soft X-ray bands, is adequately described by the response in the neutral Fe Kα line at 6.4 keV for which we use fully general relativistic ray-tracing simulations to determine its time evolution. These response functions, and thus the corresponding time-lag spectra, yield much more realistic results than the commonly used, but erroneous, top-hat models. Additionally, we parametrize the positive part of the time-lag spectra (typically seen below 10-4 Hz) by a power law. We find that the best-fitting black hole (BH) masses, M, agree quite well with those derived by other methods, thus providing us with a new tool for BH mass determination. We find no evidence for any correlation between M and the BH spin parameter, α, the viewing angle, θ, or the height of the X-ray source above the disc, h. Also on average, the X-ray source lies only around 3.7 gravitational radii above the accretion disc and θ is distributed uniformly between 20° and 60°. Finally, there is a tentative indication that the distribution of α may be bimodal above and below 0.62.

  9. Dynamical Relativistic Systems and the Generalized Gauge Fields of Manifestly Covariant Theories

    CERN Document Server

    Horwitz, L P

    1998-01-01

    The problem of the classical non-relativistic electromagnetically kicked oscillator can be cast into the form of an iterative map on phase space. The original work of Zaslovskii et al showed that the resulting evolution contains a stochastic flow in phase space to unbounded energy. Subsequent studies have formulated the problem in terms of a relativistically charged particle in interaction with the electromagnetic field. We review the standard derivation of the covariant Lorentz force, and review the structure of the relativistic equations used to study this problem. We show that the Lorentz force equation can be derived as well from the manifestly covariant mechanics of Stueckelberg in the presence of a standard Maxwell field. We show how this agreement is achieved, and criticize some of the fundamental assumptions underlying these derivations. We argue that a more complete theory, involving ``off-shell'' electromagnetic fields should be utilized. We then discuss the formulation of the off-shell electromagne...

  10. The effects of structure anisotropy on lensing observables in an exact general relativistic setting for precision cosmology

    CERN Document Server

    Troxel, M A; Peel, Austin

    2013-01-01

    The study of relativistic, higher order and nonlinear effects has become necessary in recent years in the pursuit of precision cosmology. We develop and apply here a framework to study gravitational lensing in exact models in general relativity that are not restricted to homogeneity and isotropy, and where full nonlinearity and relativistic effects are included. We apply the framework to a specific, anisotropic galaxy cluster model which is based on a modified NFW halo density profile and described by the Szekeres metric. We examine the effects of increasing levels of anisotropy in the galaxy cluster on lensing observables like the convergence and shear for various lensing geometries, finding a strong nonlinear response in both the convergence and shear for rays passing through anisotropic regions of the cluster. Deviation from the expected values in a spherically symmetric structure are asymmetric with respect to path direction and thus will persist as a statistical effect when averaged over some ensemble of...

  11. Rapid Enhancement in General Relativistic Precession Rates due to Kozai Mechanism in Solar System Bodies

    Science.gov (United States)

    Sekhar, Aswin; Asher, David; Morbidelli, Alessandro; Werner, Stephanie; Vaubaillon, Jeremie; Li, Gongjie

    2017-06-01

    Two well known phenomena in orbital dynamics associated with low perihelion distance bodies are general relativistic (GR) precession and Lidov-Kozai (LK) oscillations.In this work, we are interested to identify bodies evolving in the near future (i.e. thousands of years in this case) into rapid sungrazing and sun colliding phases and undergoing inclination flips, due to LK like oscillations and being GR active at the same time. We find that LK mechanism leads to secular lowering of perihelion distance which in turn leads to a huge increase in GR precession of the argument of pericentre depending on the initial orbital elements. This in turn gives feedback to the LK mechanism as the eccentricity, inclination and argument of pericentre in Kozai cycles are closely correlated. In this work, we find real examples of solar system bodies which show rapid enhancement in GR precession rates due to LK like oscillations and there are cases where GR precession rate peaks to about 60 times that of the GR precession of Mercury thus showing the strength and complementary nature between these two dynamical phenomena.An analytical treatment is done on few bodies to understand the difference in their orbital evolution in the context of LK mechanism with and without GR precession term by incorporating suitable Hamiltonian dynamics. This result is subsequently matched using numerical integrations to find direct correlations. Real solar system bodies showing both GR precession and LK like oscillations are identified using compiled observational records from IAU-Minor Planet Center, Cometary Catalogue, IAU-Meteor Data Center and performing analytical plus numerical tests on them. This intermediate state (where GR and LK effects are comparable and co-exist) brings up the interesting possibility of drastic changes in GR precession rates during orbital evolution due to sungrazing and sun colliding phases induced by the LK like mechanism, thus combining both these important effects in a

  12. General framework of the non-perturbative renormalization group for non-equilibrium steady states

    Energy Technology Data Exchange (ETDEWEB)

    Canet, Leonie [Laboratoire de Physique et Modelisation des Milieux Condenses, Universite Joseph Fourier Grenoble I-CNRS, BP166, 38042 Grenoble Cedex (France); Chate, Hugues [Service de Physique de l' Etat Condense, CEA-Saclay, 91191 Gif-sur-Yvette Cedex (France); Delamotte, Bertrand, E-mail: leonie.canet@grenoble.cnrs.fr [Laboratoire de Physique Theorique de la Matiere Condensee, Universite Pierre et Marie Curie, Paris VI, CNRS UMR 7600, 4 Place Jussieu, 75252 Paris Cedex 05 (France)

    2011-12-09

    This paper is devoted to presenting in detail the non-perturbative renormalization group (NPRG) formalism to investigate out-of-equilibrium systems and critical dynamics in statistical physics. The general NPRG framework for studying non-equilibrium steady states in stochastic models is expounded and fundamental technicalities are stressed, mainly regarding the role of causality and of It o-bar 's discretization. We analyze the consequences of It o-bar 's prescription in the NPRG framework and eventually provide an adequate regularization to encode them automatically. Besides, we show how to build a supersymmetric NPRG formalism with emphasis on time-reversal symmetric problems, whose supersymmetric structure allows for a particularly simple implementation of NPRG in which causality issues are transparent. We illustrate the two approaches on the example of Model A within the derivative expansion approximation at order 2 and check that they yield identical results. We stress, though, that the framework presented here also applies to genuinely out-of-equilibrium problems. (paper)

  13. Social security in a general equilibrium model with endogenous government behavior.

    Science.gov (United States)

    Drissen, E; Van Winden, F

    1991-05-01

    "In this paper attention is focused on the economic and political effects of an aging population. For that purpose, a general equilibrium model is used that allows for an endogenous analysis of decision making on government policies. We concentrate here on the effects of an aging population on expenditures and levels of social security benefits, the provision of public goods and services, the private output and intergenerational conflicts. Special attention will be paid to the effects of changes in the retirement age and in capital endowments. Furthermore, the effects of issues related to aging, as changes in the political influence structure and the motive of other-directedness by others, are investigated."

  14. Quasi-equilibrium sequences of binary strange quark stars in general relativity

    Science.gov (United States)

    Limousin, Francois; Gondek-Rosińska, Dorota; Gourgoulhon, Eric

    2004-12-01

    Inspiraling compact binaries are expected to be the strongest sources of gravitational waves for VIRGO, LIGO and other laser interferometers. We present the first computations of quasi-equilibrium sequences of compact binaries containing two strange quark stars (which are currently considered as a possible alternative to neutron stars). We study a precoalescing stage in the conformal flatness approximation of general relativity using a multidomain spectral method. A hydrodynamical treatment is performed under the assumption that the flow is either rigidly rotating or irrotational. In each of those cases, we show the differences in the gravitational waves signal from neutron stars described by polytropic equation of state.

  15. Econometrics and data of the 9 sector Dynamic General Equilibrium Model. Volume III. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Berndt, E.R.; Fraumeni, B.M.; Hudson, E.A.; Jorgenson, D.W.; Stoker, T.M.

    1981-03-01

    This report presents the econometrics and data of the 9 sector Dynamic General Equilibrium Model. There are two key components of 9DGEM - the model of household behavior and the model of produconcrneer behavior. The household model is concerned with decisions on consumption, saving, labor supply and the composition of consumption. The producer model is concerned with output price formation and determination of input patterns and purchases for each of the nine producing sectors. These components form the behavioral basis of DGEM. The remaining components are concerned with constraints, balance conditions, accounting, and government revenues and expenditures (these elements are developed in the report on the model specification).

  16. GPU-based four-dimensional general-relativistic ray tracing

    Science.gov (United States)

    Kuchelmeister, Daniel; Müller, Thomas; Ament, Marco; Wunner, Günter; Weiskopf, Daniel

    2012-10-01

    This paper presents a new general-relativistic ray tracer that enables image synthesis on an interactive basis by exploiting the performance of graphics processing units (GPUs). The application is capable of visualizing the distortion of the stellar background as well as trajectories of moving astronomical objects orbiting a compact mass. Its source code includes metric definitions for the Schwarzschild and Kerr spacetimes that can be easily extended to other metric definitions, relying on its object-oriented design. The basic functionality features a scene description interface based on the scripting language Lua, real-time image output, and the ability to edit almost every parameter at runtime. The ray tracing code itself is implemented for parallel execution on the GPU using NVidia's Compute Unified Device Architecture (CUDA), which leads to performance improvement of an order of magnitude compared to a single CPU and makes the application competitive with small CPU cluster architectures. Program summary Program title: GpuRay4D Catalog identifier: AEMV_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEMV_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 73649 No. of bytes in distributed program, including test data, etc.: 1334251 Distribution format: tar.gz Programming language: C++, CUDA. Computer: Linux platforms with a NVidia CUDA enabled GPU (Compute Capability 1.3 or higher), C++ compiler, NVCC (The CUDA Compiler Driver). Operating system: Linux. RAM: 2 GB Classification: 1.5. External routines: OpenGL Utility Toolkit development files, NVidia CUDA Toolkit 3.2, Lua5.2 Nature of problem: Ray tracing in four-dimensional Lorentzian spacetimes. Solution method: Numerical integration of light rays, GPU-based parallel programming using CUDA, 3D

  17. A dynamic general equilibrium analysis on fostering a hydrogen economy in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Jeong Hwan [Climate Change Research Dep., Korea Energy Economics Institute, Uiwang-si, Gyeonggi-do (Korea, Republic of); Cho, Gyeong-Lyeob [Korea Economics Research Institute, Yoido-dong, Yeongdungpo-ku, Seoul (Korea, Republic of)

    2010-09-15

    Hydrogen is anticipated to become one of the major alternative energy technologies for a sustainable energy system. This study analyzes the dynamic economic impacts of building a hydrogen economy in Korea employing a dynamic Computable General Equilibrium (CGE) model. As a frontier technology, hydrogen is featured as having a slow diffusion rate due to option value, positive externality, resistance of old technology, and complementary vintages. Without government intervention, hydrogen-derived energy will supply up to 6.5% of final energy demand by 2040. Simulation outcomes show that as price subsidy rates increase by 10%, 20%, and 30%, hydrogen demand will increase by 9.2%, 15.2%, and 37.7%, respectively, of final energy demand by 2040. The output of the transportation sector will increase significantly, while demands for oil and electricity will decline. Demands for coal and LNG will experience little change. Household consumption will decline because of the increase of income taxes. Overall GDP will increase because of the increase in exports and investments. CO{sub 2} emission will decline for medium and high subsidy rate cases, but increase for low subsidy cases. Ultimately, subsidy policy on hydrogen will not be an effective measure for mitigating CO{sub 2} emission in Korea when considering dynamic general equilibrium effects. (author)

  18. General equilibrium effects of a supply side GHG mitigation option under the Clean Development Mechanism.

    Science.gov (United States)

    Timilsina, Govinda R; Shrestha, Ram M

    2006-09-01

    The Clean Development Mechanism (CDM) under the Kyoto Protocol to the United Nations Framework Convention on Climate Change is considered a key instrument to encourage developing countries' participation in the mitigation of global climate change. Reduction of greenhouse gas (GHG) emissions through the energy supply and demand side activities are the main options to be implemented under the CDM. This paper analyses the general equilibrium effects of a supply side GHG mitigation option-the substitution of thermal power with hydropower--in Thailand under the CDM. A static multi-sector general equilibrium model has been developed for the purpose of this study. The key finding of the study is that the substitution of electricity generation from thermal power plants with that from hydropower plants would increase economic welfare in Thailand. The supply side option would, however, adversely affect the gross domestic product (GDP) and the trade balance. The percentage changes in economic welfare, GDP and trade balance increase with the level of substitution and the price of certified emission reduction (CER) units.

  19. Welfare implications of energy and environmental policies: A general equilibrium approach

    Science.gov (United States)

    Iqbal, Mohammad Qamar

    Government intervention and implementation of policies can impose a financial and social cost. To achieve a desired goal there could be several different alternative policies or routes, and government would like to choose the one which imposes the least social costs or/and generates greater social benefits. Therefore, applied welfare economics plays a vital role in public decision making. This paper recasts welfare measure such as equivalent variation, in terms of the prices of factors of production rather than product prices. This is made possible by using duality theory within a general equilibrium framework and by deriving alternative forms of indirect utility functions and expenditure functions in factor prices. Not only we are able to recast existing welfare measures in factor prices, we are able to perform a true cost-benefit analysis of government policies using comparative static analysis of different equilibria and breaking up monetary measure of welfare change such as equivalent variation into its components. A further advantage of our research is demonstrated by incorporating externalities and public goods in the utility function. It is interesting that under a general equilibrium framework optimal income tax tends to reduce inequalities. Results show that imposition of taxes at socially optimal rates brings a net gain to the society. It was also seen that even though a pollution tax may reduce GDP, it leads to an increase in the welfare of the society if it is imposed at an optimal rate.

  20. A computable general equilibrium assessment of the impact of illegal immigration on the Greek economy.

    Science.gov (United States)

    Sarris, A H; Zografakis, S

    1999-01-01

    This paper presents a theoretical and empirical analysis of the impact of illegal immigrants on the small type economy of Greece by using the multisectoral computable general equilibrium model. The theoretical analysis utilizes a model showing that there is no equivocal case for illegal immigration leading to the decline in the real wages of unskilled labor and increases in the real wages of skilled labor. The empirical analysis uses an applied general equilibrium model for Greece, showing that the inflow of illegal immigrants has resulted in declines of the real disposable incomes of two classes of households, namely, those headed by an unskilled person, and those belonging to the poor and middle class income bracket. The results, on the other hand, showed that the large increase in the influx of illegal immigrants is macroeconomically beneficial, having significant adverse distribution implications when flexible wage adjustment is assumed in various labor markets. It appears that unskilled and hired agricultural workers are among those that are severely affected by the inflow of illegal workers. The results also appear to be fairly sensitive with respect to the elasticities of labor supply and demand, while they appear to be quite insensitive to the elasticity of substitution in import demand and export supply. Furthermore, it is also insensitive to the various parameters concerning the structure of the illegal labor market such as the amount of wage differential between illegal and domestic unskilled labor as well as the monetary amounts that illegal laborers remit abroad.

  1. Change in General Relativistic precession rates due to Lidov-Kozai oscillations in the Solar System

    Science.gov (United States)

    Sekhar, Aswin; Asher, David J.; Werner, Stephanie C.; Vaubaillon, Jeremie; Li, Gongjie

    2017-04-01

    Introduction: Two well known phenomena associated with low perihelion distance bodies in orbital dynamics are general relativistic (GR) precession and Lidov-Kozai (LK) oscillations. The accurate prediction of the perihelion shift of Mercury in accord with real observations is one of the significant triumphs of the general theory of relativity developed by Einstein. The Lidov-Kozai mechanism was first proposed and derived by Kozai and independently by Lidov explaining the periodic exchange between eccentricities e and inclinations i thereby increasing or decreasing the perihelion distance q secularly in the orbiting body. Co-existence of GR Precession and LK Oscillations: In this work, we were interested to identify bodies evolving in the near future (i.e. thousands of years in this case) into rapid sungrazing and sun colliding phases and undergoing inclination flips, due to LK oscillations and being GR active at the same time. Of all the bodies we checked from the IAU-Minor Planet Center, and Marsden plus Kracht families from the comet catalogue, 96P/Machholz 1 stands out because it shows all these trends in the near future. LK leads to secular lowering of q which in turn leads to a huge increase in GR precession of argument of pericentre. This in turn gives feedback to the LK mechanism as the e,i and argument of pericentre in Kozai cycles are closely correlated. In this work, we find real examples of solar system bodies which show the continuum nature between GR precession domi-nant and LK mechanism dominant regimes. Results and Discussion: We have shown that there are bodies in the solar system in which both GR precession and LK mechanism can co-exist at the same time and for which these effects can be measured and identified using analytical and numerical techniques. Thus there is a continuum of bodies encompassing, firstly GR precession dominant, secondly GR precession plus LK mechanism co-existing and finally LK mechanism dominant states which are all

  2. Considerations in Applying the General Equilibrium Approach to Environmental Health Assessment

    Institute of Scientific and Technical Information of China (English)

    YUE WAN; HONG-WEI YANG; TOSHIHIKO MASUI

    2005-01-01

    There are currently two commonly used approaches to assessing economic impacts of health damage resulting from environmental pollution: human capital approach (HCA) and willingness-to-pay (WTP). WTP can be further divided into averted expenditure approach (AEA), hedonic wage approach (HWA), contingent valuation approach (CVA) and hedonic price approach (HPA). A general review of the principles behind these approaches by the authors indicates that these methods are incapable of unveiling the mechanism of health impact from the point of view of national economy. On a basis of economic system, the shocks brought about by health effects of environmental pollution change the labor supply and medical expenditure, which in turn affects the level of production activity in each sector and the total final consumption pattern of the society. The general equilibrium approach within the framework of macroeconomic theory is able to estimate the health impact on national economy comprehensively and objectively. Its mechanism and applicability are discussed in detail by the authors.

  3. Considerations in applying the general equilibrium approach to environmental health assessment.

    Science.gov (United States)

    Wan, Yue; Yang, Hong-Wei; Masui, Toshihiko

    2005-10-01

    There are currently two commonly used approaches to assessing economic impacts of health damage resulting from environmental pollution: human capital approach (HCA) and willingness-to-pay (WTP). WTP can be further divided into averted expenditure approach (AEA), hedonic wage approach (HWA), contingent valuation approach (CVA) and hedonic price approach (HPA). A general review of the principles behind these approaches by the authors indicates that these methods are incapable of unveiling the mechanism of health impact from the point of view of national economy. On a basis of economic system, the shocks brought about by health effects of environmental pollution change the labor supply and medical expenditure, which in turn affects the level of production activity in each sector and the total final consumption pattern of the society. The general equilibrium approach within the framework of macroeconomic theory is able to estimate the health impact on national economy comprehensively and objectively. Its mechanism and applicability are discussed in detail by the authors.

  4. Relativistic Hydrodynamics in Heavy-Ion Collisions: General Aspects and Recent Developments

    Directory of Open Access Journals (Sweden)

    Amaresh Jaiswal

    2016-01-01

    Full Text Available Relativistic hydrodynamics has been quite successful in explaining the collective behaviour of the QCD matter produced in high energy heavy-ion collisions at RHIC and LHC. We briefly review the latest developments in the hydrodynamical modeling of relativistic heavy-ion collisions. Essential ingredients of the model such as the hydrodynamic evolution equations, dissipation, initial conditions, equation of state, and freeze-out process are reviewed. We discuss observable quantities such as particle spectra and anisotropic flow and effect of viscosity on these observables. Recent developments such as event-by-event fluctuations, flow in small systems (proton-proton and proton-nucleus collisions, flow in ultracentral collisions, longitudinal fluctuations, and correlations and flow in intense magnetic field are also discussed.

  5. A New Multi-dimensional General Relativistic Neutrino Hydrodynamics Code for Core-collapse Supernovae. IV. The Neutrino Signal

    Science.gov (United States)

    Müller, Bernhard; Janka, Hans-Thomas

    2014-06-01

    Considering six general relativistic, two-dimensional (2D) supernova (SN) explosion models of progenitor stars between 8.1 and 27 M ⊙, we systematically analyze the properties of the neutrino emission from core collapse and bounce to the post-explosion phase. The models were computed with the VERTEX-COCONUT code, using three-flavor, energy-dependent neutrino transport in the ray-by-ray-plus approximation. Our results confirm the close similarity of the mean energies, langErang, of \\bar{\

  6. Mariage des maillages: A new 3D general relativistic hydro code for simulation of gravitational waves from core-collapses.

    Science.gov (United States)

    Novak, Jerome; Dimmelmeier, Harrald; Font-Roda, Jose A.

    2004-12-01

    We present a new three-dimensional general relativistic hydrodynamics code which can be applied to study stellar core collapses and the resulting gravitational radiation. This code uses two different numerical techniques to solve partial differential equations arising in the model: high-resolution shock capturing (HRSC) schemes for the evolution of hydrodynamic quantities and spectral methods for the solution of Einstein equations. The equations are written and solved using spherical polar coordinates, best suited to stellar topology. Einstein equations are formulated within the 3+1 formalism and conformal flat condition (CFC) for the 3-metric and gravitational radiation is extracted using Newtonian quadrupole formulation.

  7. Final Technical Report: "Representing Endogenous Technological Change in Climate Policy Models: General Equilibrium Approaches"

    Energy Technology Data Exchange (ETDEWEB)

    Ian Sue Wing

    2006-04-18

    The research supported by this award pursued three lines of inquiry: (1) The construction of dynamic general equilibrium models to simulate the accumulation and substitution of knowledge, which has resulted in the preparation and submission of several papers: (a) A submitted pedagogic paper which clarifies the structure and operation of computable general equilibrium (CGE) models (C.2), and a review article in press which develops a taxonomy for understanding the representation of technical change in economic and engineering models for climate policy analysis (B.3). (b) A paper which models knowledge directly as a homogeneous factor, and demonstrates that inter-sectoral reallocation of knowledge is the key margin of adjustment which enables induced technical change to lower the costs of climate policy (C.1). (c) An empirical paper which estimates the contribution of embodied knowledge to aggregate energy intensity in the U.S. (C.3), followed by a companion article which embeds these results within a CGE model to understand the degree to which autonomous energy efficiency improvement (AEEI) is attributable to technical change as opposed to sub-sectoral shifts in industrial composition (C.4) (d) Finally, ongoing theoretical work to characterize the precursors and implications of the response of innovation to emission limits (E.2). (2) Data development and simulation modeling to understand how the characteristics of discrete energy supply technologies determine their succession in response to emission limits when they are embedded within a general equilibrium framework. This work has produced two peer-reviewed articles which are currently in press (B.1 and B.2). (3) Empirical investigation of trade as an avenue for the transmission of technological change to developing countries, and its implications for leakage, which has resulted in an econometric study which is being revised for submission to a journal (E.1). As work commenced on this topic, the U.S. withdrawal

  8. Capital accumulation, income distribution and endogenous fertility in an overlapping generations general equilibrium model.

    Science.gov (United States)

    Raut, L K

    1991-01-01

    A study is conducted in attempts to increase the understanding of the links between macroeconomic effects and causes of population growth in formulating policy. An overlapping generations general equilibrium model is employed aggregating household decisions about fertility, savings, and investment in the human capital of children with the objective of studying intertemporal relationships among population growth, income distribution, inter-generation social mobility, skill composition of the labor force, and household income. As a result of endogenous fertility, the equilibrium path attains steady state from the second generation. Income tax transfer, child taxation, and social security taxation policies are also examined in the paper. A structural explanation is given for the inverse household income-child quantity and negative child quality-quantity relationships seen in developing countries. In a Cobb-Douglas economy, these relationships hold in the short-run, potentially working over the long-run in other economies. Overall, the model shows that group interests may hinder emergence of perfect capital markets with private initiatives. Where developing countries are concerned, these results have strong implications for population policy. A policy mix of building good quality schools, or subsidizing rural education, introducing a formal social security program, and providing high-yield, risk-free investments, banking, and insurance services to the poor is recommended.

  9. THE GENERALIZED MAXIMUM LIKELIHOOD METHOD APPLIED TO HIGH PRESSURE PHASE EQUILIBRIUM

    Directory of Open Access Journals (Sweden)

    Lúcio CARDOZO-FILHO

    1997-12-01

    Full Text Available The generalized maximum likelihood method was used to determine binary interaction parameters between carbon dioxide and components of orange essential oil. Vapor-liquid equilibrium was modeled with Peng-Robinson and Soave-Redlich-Kwong equations, using a methodology proposed in 1979 by Asselineau, Bogdanic and Vidal. Experimental vapor-liquid equilibrium data on binary mixtures formed with carbon dioxide and compounds usually found in orange essential oil were used to test the model. These systems were chosen to demonstrate that the maximum likelihood method produces binary interaction parameters for cubic equations of state capable of satisfactorily describing phase equilibrium, even for a binary such as ethanol/CO2. Results corroborate that the Peng-Robinson, as well as the Soave-Redlich-Kwong, equation can be used to describe phase equilibrium for the following systems: components of essential oil of orange/CO2.Foi empregado o método da máxima verossimilhança generalizado para determinação de parâmetros de interação binária entre os componentes do óleo essencial de laranja e dióxido de carbono. Foram usados dados experimentais de equilíbrio líquido-vapor de misturas binárias de dióxido de carbono e componentes do óleo essencial de laranja. O equilíbrio líquido-vapor foi modelado com as equações de Peng-Robinson e de Soave-Redlich-Kwong usando a metodologia proposta em 1979 por Asselineau, Bogdanic e Vidal. A escolha destes sistemas teve como objetivo demonstrar que o método da máxima verosimilhança produz parâmetros de interação binária, para equações cúbicas de estado capazes de descrever satisfatoriamente até mesmo o equilíbrio para o binário etanol/CO2. Os resultados comprovam que tanto a equação de Peng-Robinson quanto a de Soave-Redlich-Kwong podem ser empregadas para descrever o equilíbrio de fases para o sistemas: componentes do óleo essencial de laranja/CO2.

  10. General multi-group macroscopic modeling for thermo-chemical non-equilibrium gas mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yen, E-mail: yen.liu@nasa.gov; Vinokur, Marcel [NASA Ames Research Center, Moffett Field, California 94035 (United States); Panesi, Marco; Sahai, Amal [University of Illinois, Urbana-Champaign, Illinois 61801 (United States)

    2015-04-07

    This paper opens a new door to macroscopic modeling for thermal and chemical non-equilibrium. In a game-changing approach, we discard conventional theories and practices stemming from the separation of internal energy modes and the Landau-Teller relaxation equation. Instead, we solve the fundamental microscopic equations in their moment forms but seek only optimum representations for the microscopic state distribution function that provides converged and time accurate solutions for certain macroscopic quantities at all times. The modeling makes no ad hoc assumptions or simplifications at the microscopic level and includes all possible collisional and radiative processes; it therefore retains all non-equilibrium fluid physics. We formulate the thermal and chemical non-equilibrium macroscopic equations and rate coefficients in a coupled and unified fashion for gases undergoing completely general transitions. All collisional partners can have internal structures and can change their internal energy states after transitions. The model is based on the reconstruction of the state distribution function. The internal energy space is subdivided into multiple groups in order to better describe non-equilibrium state distributions. The logarithm of the distribution function in each group is expressed as a power series in internal energy based on the maximum entropy principle. The method of weighted residuals is applied to the microscopic equations to obtain macroscopic moment equations and rate coefficients succinctly to any order. The model’s accuracy depends only on the assumed expression of the state distribution function and the number of groups used and can be self-checked for accuracy and convergence. We show that the macroscopic internal energy transfer, similar to mass and momentum transfers, occurs through nonlinear collisional processes and is not a simple relaxation process described by, e.g., the Landau-Teller equation. Unlike the classical vibrational energy

  11. General multi-group macroscopic modeling for thermo-chemical non-equilibrium gas mixtures

    Science.gov (United States)

    Liu, Yen; Panesi, Marco; Sahai, Amal; Vinokur, Marcel

    2015-04-01

    This paper opens a new door to macroscopic modeling for thermal and chemical non-equilibrium. In a game-changing approach, we discard conventional theories and practices stemming from the separation of internal energy modes and the Landau-Teller relaxation equation. Instead, we solve the fundamental microscopic equations in their moment forms but seek only optimum representations for the microscopic state distribution function that provides converged and time accurate solutions for certain macroscopic quantities at all times. The modeling makes no ad hoc assumptions or simplifications at the microscopic level and includes all possible collisional and radiative processes; it therefore retains all non-equilibrium fluid physics. We formulate the thermal and chemical non-equilibrium macroscopic equations and rate coefficients in a coupled and unified fashion for gases undergoing completely general transitions. All collisional partners can have internal structures and can change their internal energy states after transitions. The model is based on the reconstruction of the state distribution function. The internal energy space is subdivided into multiple groups in order to better describe non-equilibrium state distributions. The logarithm of the distribution function in each group is expressed as a power series in internal energy based on the maximum entropy principle. The method of weighted residuals is applied to the microscopic equations to obtain macroscopic moment equations and rate coefficients succinctly to any order. The model's accuracy depends only on the assumed expression of the state distribution function and the number of groups used and can be self-checked for accuracy and convergence. We show that the macroscopic internal energy transfer, similar to mass and momentum transfers, occurs through nonlinear collisional processes and is not a simple relaxation process described by, e.g., the Landau-Teller equation. Unlike the classical vibrational energy

  12. Thermodynamics and flow-frames for dissipative relativistic fluids

    Energy Technology Data Exchange (ETDEWEB)

    Ván, P. [Dept. of Theoretical Physics, Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, H-1525 Budapest, Konkoly Thege Miklós út 29-33, Hungary and Dept. of Energy Engineering, Budapest Univ. of Technology and Econ (Hungary); Biró, T. S. [Dept. of Theoretical Physics, Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, H-1525 Budapest, Konkoly Thege Miklós út 29-33 (Hungary)

    2014-01-14

    A general thermodynamic treatment of dissipative relativistic fluids is introduced, where the temperature four vector is not parallel to the velocity field of the fluid. Generic stability and kinetic equilibrium points out a particular thermodynamics, where the temperature vector is parallel to the enthalpy flow vector and the choice of the flow fixes the constitutive functions for viscous stress and heat. The linear stability of the homogeneous equilibrium is proved in a mixed particle-energy flow-frame.

  13. Generalized Quantum Master Equations In and Out of Equilibrium: When Can One Win?

    CERN Document Server

    Kelly, Aaron; Wang, Lu; Markland, Thomas E

    2016-01-01

    Generalized quantum master equations (GQMEs) are an important tool in modeling chemical and physical processes. The central quantity in these approaches is the memory kernel, which encodes the effect of the projected dynamical degrees of freedom on the observable of interest. For a large number of problems it has been shown that exact and approximate methods can be made dramatically more efficient, and in the latter case more accurate, by proceeding via the GQME formalism. However, there are many situations where utilizing the GQME approach seems to offer no advantage over a direct evaluation of the property of interest. The development of a more detailed understanding of the conditions under which these methods will offer benefits would thus greatly enhance their utility. Here, we derive exact expressions for the memory kernel obtained from projection operators for systems both in and out of equilibrium, and show the conditions under which these expressions will be guaranteed to return an identical result to...

  14. Application of dynamic stochastic general equilibrium models to the case of the Serbian economy

    Directory of Open Access Journals (Sweden)

    Urošević Branko

    2014-01-01

    Full Text Available This paper proposes a dynamic stochastic general equilibrium (DSGE model for the Serbian economy. It is a modification of the existing models of Goodhart, Osorio and Tsomocos (2009 and Martinez and Tsomocos (2012. The model introduces important features of the Serbian economy, financial dollarization and foreign ownership of the banking system, while retaining the most important element of the reference models, financial friction. To solve the model we use Dynare, a specialized Matlab program for solving DSGE models. The model is subject to three different shocks: monetary, productivity, and regulatory, and the results are presented in the form of impulse response functions. It is concluded that the proposed platform has good characteristics, but its complete application to the case of the Serbian economy requires further research. [Projekat Ministarstva nauke Republike Srbije, br. 179005

  15. National CO{sub 2} policy and externalities: some general equilibrium results for Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Felder, S. [Otto-von-Guericke University, Magdeburg (Germany). Institute of Social Medicine and Health Economics; Schleiniger, R. [University of Zurich (Switzerland). Institute for Empirical Research in Economics

    2002-09-01

    Switzerland, following the Kyoto agreement, plans to reduce CO{sub 2} emissions by 10% over the next decade with a tax on the use of fossil fuels. This policy, while having a marginal effect on global CO{sub 2} emission levels, will have a positive effect on local environmental quality. However, since different sources of energy produce different local external effects, a uniform CO{sub 2} tax is ill-targeted. This paper shows that a policy setting tax rates equal to the lower bounds of the estimated local marginal external effects would reduce the national CO{sub 2} level by 30%. Using a computable general equilibrium model of the Swiss economy, it also finds substantial efficiency gains of Pigovian taxes as compared to a uniform CO{sub 2} tax. (author)

  16. National CO{sub 2} policy and externalities. Some general equilibrium results for Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Felder, Stefan [Institute of Social Medicine and Health Economics, Otto-von-Guericke University Magdeburg, Leipziger Str. 44, D-39120 Magdeburg (Germany); Schleiniger, Reto [Institute for Empirical Research in Economics, University of Zurich, Bluemlisalpstr. 10, CH-8006 Zurich (Switzerland)

    2002-09-01

    Switzerland, following the Kyoto agreement, plans to reduce CO{sub 2} emissions by 10% over the next decade with a tax on the use of fossil fuels. This policy, while having a marginal effect on global CO{sub 2} emission levels, will have a positive effect on local environmental quality. However, since different sources of energy produce different local external effects, a uniform CO{sub 2} tax is ill targeted. This paper shows that a policy setting tax rates equal to the lower bounds of the estimated local marginal external effects would reduce the national CO{sub 2} level by 30%. Using a computable general equilibrium model of the Swiss economy, it also finds substantial efficiency gains of Pigovian taxes as compared to a uniform CO{sub 2} tax.

  17. Impacts of integration of Brazil with the European Union through a general equilibrium model

    Directory of Open Access Journals (Sweden)

    Ezequiel Insaurriaga Megiato

    2016-01-01

    Full Text Available This study analyses the bilateral trade between Brazil and the European Union (EU in the period 2002–2012, examining the trade opportunities based on a full integration process. It employs a computable general equilibrium model from the Global Trade Analysis Project (GTAP, aiming at identifying the sectors that would benefit most from the agreement, according to their technological intensity. The results show that Brazil benefits most from the agreement in terms of welfare and would also increase the country's exports of primary products. However, it would cause a decrease in production and exports of products with higher technological intensity, increasing the country's imports from the EU, in line with their comparative advantages.

  18. Hurricane Sandy Economic Impacts Assessment: A Computable General Equilibrium Approach and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Boero, Riccardo [Los Alamos National Laboratory; Edwards, Brian Keith [Los Alamos National Laboratory

    2017-08-07

    Economists use computable general equilibrium (CGE) models to assess how economies react and self-organize after changes in policies, technology, and other exogenous shocks. CGE models are equation-based, empirically calibrated, and inspired by Neoclassical economic theory. The focus of this work was to validate the National Infrastructure Simulation and Analysis Center (NISAC) CGE model and apply it to the problem of assessing the economic impacts of severe events. We used the 2012 Hurricane Sandy event as our validation case. In particular, this work first introduces the model and then describes the validation approach and the empirical data available for studying the event of focus. Shocks to the model are then formalized and applied. Finally, model results and limitations are presented and discussed, pointing out both the model degree of accuracy and the assessed total damage caused by Hurricane Sandy.

  19. Generalized Fick Jacobs Approach for describing Adsorption Desorption Kinetics in Irregular Pores under Non Equilibrium Conditions

    CERN Document Server

    Ledesma-Durán, Aldo; Santamaría-Holek, Iván

    2016-01-01

    We present a study exploring the range of applicability of a generalized Fick Jacobs equation in the case when diffusive mass transport of a fluid along a pore includes chemical reactions in the bulk and pore surface. The study contemplates nonequilibrium boundary conditions and makes emphasis on the comparison between the predictions coming from the projected Fick Jacobs description and the corresponding predictions of the original two dimensional mass balance equation, establishing a simple cuantitative criterion of validity of the projected description. For the adsorption desorption process, we demonstrate that the length and the local curvature of the pore are the relevant geometric quantities for its description, allowing for giving very precise predictions of the mass concentration along the pore. Some schematic cases involving adsorption and chemical reaction are used to quantify with detail the concentration profiles in transient and stationary states involving equilibrium and nonequilibrium situation...

  20. General Equilibrium Analysis of Electricity Market Liberalization in Singapore: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Fenglong XIAO

    2011-12-01

    Full Text Available The liberalization in electricity market in Singapore has being undertaken for more than 15 years. This paper evaluates the influence of competition policies by computable general equilibrium (CGE model. Instead of the direct measurement of the impact of competition policy, the benefit of liberalization is reflected by the simulation of a hypothetical regulatory condition. Comparing to the regulatory scenario, simulation result implies the current liberalization raises GDP and exchange rate significantly, but also leaves the tradeoff between higher national income and lower consumer welfare to government. If such choice of economic policy is necessary for political demand, a formal legal framework is required to enforce the restoration of the economy from regulatory restrictions.

  1. Relativistic hydrodynamics from quantum field theory on the basis of the generalized Gibbs ensemble method

    CERN Document Server

    Hayata, Tomoya; Hongo, Masaru; Noumi, Toshifumi

    2015-01-01

    We derive relativistic hydrodynamics from quantum field theories by assuming that the density operator is given by a local Gibbs distribution at initial time. We decompose the energy-momentum tensor and particle current into nondissipative and dissipative parts, and analyze their time-evolution in detail. Performing the path-integral formulation of the local Gibbs distribution, we microscopically derive the generating functional for the nondissipative hydrodynamics. We also construct a basis to study dissipative corrections. In particular, we derive the first-order dissipative hydrodynamic equations without choice of frame such as the Landau-Lifshitz or Eckart frame.

  2. Generalized Rayleigh-Taylor instability in the presence of time-dependent equilibrium

    Science.gov (United States)

    Basu, B.

    1997-08-01

    Plasma instability under the combined influence of the gravity and an eastward electric field, commonly referred to as the generalized Rayleigh-Taylor instability, is considered for a time-dependent equilibrium situation. In the nighttime equatorial ionosphere the time-dependent equilibrium situation arises because of the vertically upward E0×B0 drift of the plasma in conjunction with the altitude-dependent recombination process and the collisional diffusion process. After determining the time-dependent equilibrium density and, in particular, the inverse density gradient scale length L-1, which determines the growth rate of the instability, the stability of small-amplitude perturbations is analyzed. The general solution of the problem, where the effects of all of the above-mentioned processes are included simultaneously, requires numerical analysis. In this paper the effects are studied in limiting situations for which useful analytic solutions can be obtained. The effect of diffusion on L-1 is studied by neglecting both the upward plasma drift and the altitude variation of the recombination frequency νR, and it is verified that the effect is negligible for typical values of the ionospheric parameters. The effects of the other two processes on L-1 are studied by neglecting diffusion. The effect of the altitude variation of νR on the linear growth of the perturbations is studied by adopting the so-called local approximation. It is found that the value of L-1 and hence the value of the growth rate are enhanced by the altitude variation of νR. The enhancements rapidly increase with time to large values at lower altitudes and to significant values at higher altitudes when compared with the values for the spatially uniform νR case. Consequently, the time evolution of the instability and, more importantly, the level of fluctuations at saturation will be significantly affected by the enhancements. The nonlocal aspect of the instability in the upward drifting plasma

  3. General theory of Onsager symmetries for perturbations of equilibrium and nonequilibrium steady states

    Science.gov (United States)

    Krommes, John A.; Hu, Genze

    1993-11-01

    The theory of Onsager symmetry is reconsidered from the point of view of its application to nonequilibrium, possibly turbulent steady states. A dynamical formalism based on correlation and response functions is used; understanding of its relationship to more conventional approaches based on entropy production enables one to resolve various confusions about the proper use of the theory, even near thermal equilibrium. Previous claims that ``kinematic'' flows must be excluded from considerations of Onsager symmetry are refuted by showing that suitably defined reversible and irreversible parts of the Onsager matrix separately obey the appropriate symmetry; fluctuating hydrodynamics serves as an example. It is shown that Onsager symmetries are preserved under arbitrary covariant changes of variables; the Weinhold metric is used as a fundamental tensor. Covariance is used to render moot the controversy over the proper choice of fluxes and forces in neoclassical plasma transport theory. The fundamental distinction between the fully contravariant Onsager matrix Lij and its mixed representation Lij is emphasized and used to explain why some previous workers have failed to find Onsager symmetry around turbulent steady states. The generalized Onsager theorem of Dufty and Rubí [Phys. Rev. A 36, 222 (1987)] is reviewed. An explicitly soluble Langevin problem is shown to violate Onsager's original symmetry but to obey the generalized theorem. The physical content of the generalized Onsager symmetry is discussed from the point of view of Nosé-Hoover dynamics. A set of extended Graham-Haken potential conditions are derived for Fokker-Planck models and shown to be consistent with the generalized Onsager relations. Finally, for quite general, possibly turbulent steady states it is argued that realizable Markovian statistical closures with underlying Langevin representations must also obey the generalized theorem. In the special case in which all state variables have even parity

  4. Understanding the Relativistic Generalization of Density Functional Theory (DFT) and Completing it in Practice

    Science.gov (United States)

    Bagayoko, Diola

    In 2014, 50 years following the introduction of density functional theory (DFT), a rigorous understanding of it was published [AIP Advances, 4, 127104 (2014)]. This understanding included necessary steps ab initio electronic structure calculations have to take if their results are to possess the full physical content of DFT. These steps guarantee the fulfillment of conditions of validity of DFT; not surprisingly, they have led to accurate descriptions of several dozens of semiconductors, from first principle, without invoking derivative discontinuity or self-interaction correction. This presentation shows the mathematically and physically rigorous understanding of the relativistic extension of DFT by Rajagopal and Callaway {Phys. Rev. B 7, 1912 (1973)]. As in the non-relativistic case, the attainment of the absolute minima of the occupied energies is a necessary condition for the corresponding current density to be that of the ground state of the system and for computational results to agree with corresponding, experimental ones. Acknowledgments:This work was funded in part by the US National Science Foundation [NSF, Award Nos. EPS-1003897, NSF (2010-2015)-RII-SUBR, and HRD-1002541], the US Department of Energy, National Nuclear Security Administration (NNSA, Award No. DE-NA0002630), LaSPACE, and LONI-SUBR.

  5. General Relativistic Radiant Shock Waves in the Post-Quasistatic Approximation

    Energy Technology Data Exchange (ETDEWEB)

    H, Jorge A Rueda [Centro de Fisica Fundamental, Universidad de Los Andes, Merida 5101, Venezuela Escuela de Fisica, Universidad Industrial de Santander, A.A. 678, Bucaramanga (Colombia); Nunez, L A [Centro de Fisica Fundamental, Universidad de Los Andes, Merida 5101, Venezuela Centro Nacional de Calculo Cientifico, Universidad de Los Andes, CeCalCULA, Corporacion Parque Tecnologico de Merida, Merida 5101, Venezuela (Venezuela)

    2007-05-15

    An evolution of radiant shock wave front is considered in the framework of a recently presented method to study self-gravitating relativistic spheres, whose rationale becomes intelligible and finds full justification within the context of a suitable definition of the post-quasistatic approximation. The spherical matter configuration is divided into two regions by the shock and each side of the interface having a different equation of state and anisotropic phase. In order to simulate dissipation effects due to the transfer of photons and/or neutrinos within the matter configuration, we introduce the flux factor, the variable Eddington factor and a closure relation between them. As we expected the strong of the shock increases the speed of the fluid to relativistic ones and for some critical values is larger than light speed. In addition, we find that energy conditions are very sensible to the anisotropy, specially the strong energy condition. As a special feature of the model, we find that the contribution of the matter and radiation to the radial pressure are the same order of magnitude as in the mant as in the core, moreover, in the core radiation pressure is larger than matter pressure.

  6. General Relativistic Hydrodynamic Simulation of Accretion Flow from a Stellar Tidal Disruption

    CERN Document Server

    Shiokawa, Hotaka; Cheng, Roseanne M; Piran, Tsvi; Noble, Scott C

    2015-01-01

    We study how the matter dispersed when a supermassive black hole tidally disrupts a star joins an accretion flow. Combining a relativistic hydrodynamic simulation of the stellar disruption with a relativistic hydrodynamics simulation of the tidal debris motion, we track such a system until ~80% of the stellar mass bound to the black hole has settled into an accretion flow. Shocks near the stellar pericenter and also near the apocenter of the most tightly-bound debris dissipate orbital energy, but only enough to make the characteristic radius comparable to the semi-major axis of the most-bound material, not the tidal radius as previously thought. The outer shocks are caused by post-Newtonian effects, both on the stellar orbit during its disruption and on the tidal forces. Accumulation of mass into the accretion flow is non-monotonic and slow, requiring ~3--10x the orbital period of the most tightly-bound tidal streams, while the inflow time for most of the mass may be comparable to or longer than the mass accu...

  7. General relativistic hydrodynamic flows around a static compact object in final stages of accretion flow

    Directory of Open Access Journals (Sweden)

    J Ghanbari

    2009-12-01

    Full Text Available Dynamics of stationary axisymmetric configuration of the viscous accreting fluids surrounding a non-rotating compact object in final stages of accretion flow is presented here. For the special case of thin disk approximation, the relativistic fluid equations ignoring self-gravity of the disk are derived in Schwarzschild geometry. For two different state equations, two sets of self-consistent analytical solutions of fully relativistic fluid equations are obtained separately. The effect of bulk viscosity coefficient on the physical functions are investigated for each state equation, as well as the bounds that exert on the free parameters due to the condition of accretion flow in the last stages. The solutions found show that the radial and azimuthal velocities, density and pressure of the fluid increase inwards for both state equations. Also, viscosity has no effect on the velocities and density distributions in both state equations. Two state equations show different types of behavior with respect to the bulk viscosity coefficient. For p=K state equation, if there is no bulk viscosity, the pressure remains constant throughout the disk, whereas with increasing bulk viscosity the pressure falls off in the inner regions but soon stabilizes at an almost constant value. However, for p=ρc2 state equation, the pressure is never constant, even in the absence of bulk viscosity. The larger the value of ηb, the higher the value of pressure in the inner regions.

  8. EXISTENCE OF GENERAL EQUILIBRIUM FOR STOCHASTIC ECONOMY WITH INFINITE-DIMENSIONAL COMMODITY SPACE AND INCOMPLETE FINANCIAL MARKETS

    Institute of Scientific and Technical Information of China (English)

    ZhangShunming

    1999-01-01

    This paper analyses the general equilibrium existence problem in a (finite) discretetime economy with infinite-dimensional commodity space and inComplete financial markets. It isassumed that the trading takes place in the sequence of spot markets and futures markets for sccurities payable in units of account. Unlimited short-selling in securities is allowed. The existence of such an equilibrium is proved under the following conditions: Mackey continuous,weakly convex ,strictly monotone,complete preferences and strictly positive endowments.

  9. Generalized non-equilibrium vertex correction method in coherent medium theory for quantum transport simulation of disordered nanoelectronics

    Science.gov (United States)

    Yan, Jiawei; Ke, Youqi

    In realistic nanoelectronics, disordered impurities/defects are inevitable and play important roles in electron transport. However, due to the lack of effective quantum transport method, the important effects of disorders remain poorly understood. Here, we report a generalized non-equilibrium vertex correction (NVC) method with coherent potential approximation to treat the disorder effects in quantum transport simulation. With this generalized NVC method, any averaged product of two single-particle Green's functions can be obtained by solving a set of simple linear equations. As a result, the averaged non-equilibrium density matrix and various important transport properties, including averaged current, disordered induced current fluctuation and the averaged shot noise, can all be efficiently computed in a unified scheme. Moreover, a generalized form of conditionally averaged non-equilibrium Green's function is derived to incorporate with density functional theory to enable first-principles simulation. We prove the non-equilibrium coherent potential equals the non-equilibrium vertex correction. Our approach provides a unified, efficient and self-consistent method for simulating non-equilibrium quantum transport through disorder nanoelectronics. Shanghaitech start-up fund.

  10. Econometrically calibrated computable general equilibrium models: Applications to the analysis of energy and climate politics

    Science.gov (United States)

    Schu, Kathryn L.

    Economy-energy-environment models are the mainstay of economic assessments of policies to reduce carbon dioxide (CO2) emissions, yet their empirical basis is often criticized as being weak. This thesis addresses these limitations by constructing econometrically calibrated models in two policy areas. The first is a 35-sector computable general equilibrium (CGE) model of the U.S. economy which analyzes the uncertain impacts of CO2 emission abatement. Econometric modeling of sectors' nested constant elasticity of substitution (CES) cost functions based on a 45-year price-quantity dataset yields estimates of capital-labor-energy-material input substitution elasticities and biases of technical change that are incorporated into the CGE model. I use the estimated standard errors and variance-covariance matrices to construct the joint distribution of the parameters of the economy's supply side, which I sample to perform Monte Carlo baseline and counterfactual runs of the model. The resulting probabilistic abatement cost estimates highlight the importance of the uncertainty in baseline emissions growth. The second model is an equilibrium simulation of the market for new vehicles which I use to assess the response of vehicle prices, sales and mileage to CO2 taxes and increased corporate average fuel economy (CAFE) standards. I specify an econometric model of a representative consumer's vehicle preferences using a nested CES expenditure function which incorporates mileage and other characteristics in addition to prices, and develop a novel calibration algorithm to link this structure to vehicle model supplies by manufacturers engaged in Bertrand competition. CO2 taxes' effects on gasoline prices reduce vehicle sales and manufacturers' profits if vehicles' mileage is fixed, but these losses shrink once mileage can be adjusted. Accelerated CAFE standards induce manufacturers to pay fines for noncompliance rather than incur the higher costs of radical mileage improvements

  11. Do general relativistic effects limit experiments to test the universality of free fall and the weak equivalence principle?

    Science.gov (United States)

    Nobili, Anna M.

    2016-12-01

    The universality of free fall and the weak equivalence principle, which are at the basis of general relativity, have been confirmed to 1 part in 1 013. Space experiments with macroscopic test masses of different composition orbiting Earth inside a low altitude satellite aim to improve this precision by 2 orders of magnitude (with the Microscope satellite launched on April 25, 2016) and up to 4 orders of magnitude (with the Galileo Galilei satellite). At such a high precision, many tiny effects must be taken into account in order to be ruled out as the source of a spurious violation signal. In this work, we investigate the general relativistic effects, including those which involve the rotation of both Earth and the test masses, and show that they are by far too small to be considered even in the most challenging experiment.

  12. Do general relativistic effects limit experiments to test the universality of free fall and the weak equivalence principle?

    CERN Document Server

    Nobili, Anna M

    2016-01-01

    The Universality of Free Fall and the Weak Equivalence Principle, which are at the basis of General Relativity, have been confirmed to 1 part in 10^13. Space experiments with macroscopic test masses of different composition orbiting the Earth inside a low altitude satellite aim at improving this precision by two orders of magnitude (with the Microscope satellite, launched on 25 April 2016) and up to four orders of magnitude (with the 'Galileo Galilei' - GG satellite). At such a high precision many tiny effects must be taken into account in order to be ruled out as the source of a spurious violation signal. In this work we investigate the general relativistic effects, including those which involve the rotation of both the source body and the test masses, and show that they are by far too small to be considered even in the most challenging experiment.

  13. Non-Perfect-Fluid Space-Times in Thermodynamic Equilibrium and Generalized Friedmann Equations

    Directory of Open Access Journals (Sweden)

    Konrad Schatz

    2016-01-01

    Full Text Available We determine the energy-momentum tensor of nonperfect fluids in thermodynamic equilibrium and, respectively, near to it. To this end, we derive the constitutive equations for energy density and isotropic and anisotropic pressure as well as for heat-flux from the corresponding propagation equations and by drawing on Einstein’s equations. Following Obukhov on this, we assume the corresponding space-times to be conform-stationary and homogeneous. This procedure provides these quantities in closed form, that is, in terms of the structure constants of the three-dimensional isometry group of homogeneity and, respectively, in terms of the kinematical quantities expansion, rotation, and acceleration. In particular, we find a generalized form of the Friedmann equations. As special cases we recover Friedmann and Gödel models as well as nontilted Bianchi solutions with anisotropic pressure. All of our results are derived without assuming any equations of state or other specific thermodynamic conditions a priori. For the considered models, results in literature are generalized to rotating fluids with dissipative fluxes.

  14. A computable general equilibrium analysis of greenhouse gas reduction paths and scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Iorwerth, A.A.; Bagnoli, P.; Dissou, Y.; Peluso, T.; Rudin, J. [Department of Finance, Ottawa, ON (Canada)

    2000-10-31

    Finance Canada conducted an analysis on behalf of the federal-provincial Climate Change Analysis and Modelling Group regarding policy options to reduce greenhouse gas (GHG) emissions. The Canadian sectoral general equilibrium model (CaSGEM) was used to simulate the Canadian economy using representative consumers and producers. The model describes the complete economy comprised of 51 sectors producing 59 goods and services. The model does not describe the transition costs of the path taken in adjusting to the new policy environment. Instead, it focuses on the Canadian economy after the impacts of new policies have been in place long enough to work themselves through the economy. It was suggested that at least some producers, particularly in electricity production, could easily replace GHG-intensive inputs with those which are less polluting. A table was included which showed the reduction in emissions from coal and natural gas predicted by the model for the electricity sector. The reduction in fuel use was also reported. It was concluded that there would be a long-run economic cost to implement the Kyoto agreement, but the cost is neither inconsequential nor enormous if the agreement is implemented in a cost-effective way. It was determined that the use of sector-specific emissions targets would add to the overall cost of implementing the Kyoto agreement without reducing the variation in economic impact across sectors. It was noted that technical assumptions have a significant bearing on the general impact and its distribution across sectors and provinces. tabs.

  15. Numerical modeling of a Global Navigation Satellite System in a general relativistic framework

    CERN Document Server

    Delva, P; Cadez, A

    2010-01-01

    In this article we model a Global Navigation Satellite System (GNSS) in a Schwarzschild space-time, as a first approximation of the relativistic geometry around the Earth. The closed time-like and scattering light-like geodesics are obtained analytically, describing respectively trajectories of satellites and electromagnetic signals. We implement an algorithm to calculate Schwarzschild coordinates of a GNSS user who receives proper times sent by four satellites, knowing their orbital parameters; the inverse procedure is implemented to check for consistency. The constellation of satellites therefore realizes a geocentric inertial reference system with no \\emph{a priori} realization of a terrestrial reference frame. We show that the calculation is very fast and could be implemented in a real GNSS, as an alternative to usual post-Newtonian corrections. Effects of non-gravitational perturbations on positioning errors are assessed, and methods to reduce them are sketched. In particular, inter-links between satelli...

  16. A general relativistic approach to the Navarro-Frenk-White (NFW) galactic halos

    CERN Document Server

    Matos, T; Sussman, R A; Matos, Tonatiuh; Nunez, Dario; Sussman, Roberto A

    2004-01-01

    In order to study their interplay with large scale cosmic evolution and with relativistic effects, such as gravitational lenses, quintessence sources or gravitational waves, we construct a post-Newtonian fluid framework for the "Navarro-Frenk-White'' (NFW) models of galactic halos that follow from N-body numerical simulations. Since these simulations are unable to resolve regions very near the halo center, the extrapolation of the fitting formula leads to a spherically averaged "universal'' density profile that diverges at the origin. We remove this inconvenient feature by replacing a small central region of the NFW halo with an interior Schwarzschild solution with constant density, continuously matched to the remaining NFW spacetime. A model of a single halo, as an isolated object with finite mass, follows by smoothly matching the NFW spacetime to a Schwarzschild vacuum exterior along the virial radius, the physical "cut-off'' customarily imposed, as the mass associated with NFW profiles diverges asymptotica...

  17. Development of General Relativistic Magnetohydrodynamic Code and its Application to Central Engine of Long Gamma-Ray Bursts

    CERN Document Server

    Nagataki, S

    2009-01-01

    In order to investigate formation of relativistic jets at the center of a progenitor of a long gamma-ray burst (GRB), we develop a two-dimensional general relativistic magnetohydrodynamic (GRMHD) code. We show the code passes many, well-known test calculations, by which the reliability of the code is confirmed. Then we perform a numerical simulation of a collapsar using a realistic progenitor model. It is shown that a jet is launched from the center of the progenitor. We also find that the mass accretion rate after the launch of the jet shows rapid time variability that resembles to a typical time profile of a GRB. The structure of the jet is similar to the previous study: a poynting flux jet is surrounded by a funnel-wall jet. Even at the final stage of the simulation, bulk Lorentz factor of the jet is still low, and total energy of the jet is still as small as 10^48 erg. However, we find that the energy flux per unit rest-mass flux is as high as 10^2 at the bottom of the jet. Thus we conclude that the bulk ...

  18. Physical-constraint-preserving Central Discontinuous Galerkin Methods for Special Relativistic Hydrodynamics with a General Equation of State

    Science.gov (United States)

    Wu, Kailiang; Tang, Huazhong

    2017-01-01

    The ideal gas equation of state (EOS) with a constant adiabatic index is a poor approximation for most relativistic astrophysical flows, although it is commonly used in relativistic hydrodynamics (RHD). This paper develops high-order accurate, physical-constraints-preserving (PCP), central, discontinuous Galerkin (DG) methods for the one- and two-dimensional special RHD equations with a general EOS. It is built on our theoretical analysis of the admissible states for RHD and the PCP limiting procedure that enforce the admissibility of central DG solutions. The convexity, scaling invariance, orthogonal invariance, and Lax–Friedrichs splitting property of the admissible state set are first proved with the aid of its equivalent form. Then, the high-order central DG methods with the PCP limiting procedure and strong stability-preserving time discretization are proved, to preserve the positivity of the density, pressure, specific internal energy, and the bound of the fluid velocity, maintain high-order accuracy, and be L1-stable. The accuracy, robustness, and effectiveness of the proposed methods are demonstrated by several 1D and 2D numerical examples involving large Lorentz factor, strong discontinuities, or low density/pressure, etc.

  19. A General Relativistic Model for Magnetic Monopole-Infused Compact Objects

    CERN Document Server

    Pazameta, Zoran

    2012-01-01

    Emergent concepts from astroparticle physics are incorporated into a classical solution of the Einstein-Maxwell equations for a binary magnetohydrodynamic fluid, in order to describe the final equilibrium state of compact objects infused with magnetic monopoles produced by proton-proton collisions within the intense dipolar magnetic fields generated by these objects during their collapse. It is found that the effective mass of such an object's acquired monopolar magnetic field is three times greater than the mass of its native fluid and monopoles combined, necessitating that the interior matter undergo a transition to a state of negative pressure in order to attain equilibrium. Assuming full symmetry between the electric and magnetic Maxwell equations yields expressions for the monopole charge density and magnetic field by direct analogy with their electrostatic equivalents; inserting these into the Einstein equations then leads to an interior metric which is well-behaved from the origin to the surface, where...

  20. GEM-E3: A computable general equilibrium model applied for Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Bahn, O. [Paul Scherrer Inst., CH-5232 Villigen PSI (Switzerland); Frei, C. [Ecole Polytechnique Federale de Lausanne (EPFL) and Paul Scherrer Inst. (Switzerland)

    2000-01-01

    The objectives of the European Research Project GEM-E3-ELITE, funded by the European Commission and coordinated by the Centre for European Economic Research (Germany), were to further develop the general equilibrium model GEM-E3 (Capros et al., 1995, 1997) and to conduct policy analysis through case studies. GEM-E3 is an applied general equilibrium model that analyses the macro-economy and its interaction with the energy system and the environment through the balancing of energy supply and demand, atmospheric emissions and pollution control, together with the fulfillment of overall equilibrium conditions. PSI's research objectives within GEM-E3-ELITE were to implement and apply GEM-E3 for Switzerland. The first objective required in particular the development of a Swiss database for each of GEM-E3 modules (economic module and environmental module). For the second objective, strategies to reduce CO{sub 2} emissions were evaluated for Switzerland. In order to develop the economic, PSI collaborated with the Laboratory of Applied Economics (LEA) of the University of Geneva and the Laboratory of Energy Systems (LASEN) of the Federal Institute of Technology in Lausanne (EPFL). The Swiss Federal Statistical Office (SFSO) and the Institute for Business Cycle Research (KOF) of the Swiss Federal Institute of Technology (ETH Zurich) contributed also data. The Swiss environmental database consists mainly of an Energy Balance Table and of an Emission Coefficients Table. Both were designed using national and international official statistics. The Emission Coefficients Table is furthermore based on know-how of the PSI GaBE Project. Using GEM-E3 Switzerland, two strategies to reduce the Swiss CO{sub 2} emissions were evaluated: a carbon tax ('tax only' strategy), and the combination of a carbon tax with the buying of CO{sub 2} emission permits ('permits and tax' strategy). In the first strategy, Switzerland would impose the necessary carbon tax to achieve

  1. Generalized Well-Posedness for Symmetric Vector Quasi-Equilibrium Problems

    Directory of Open Access Journals (Sweden)

    Wei-bing Zhang

    2015-01-01

    Full Text Available We introduce and study well-posedness in connection with the symmetric vector quasi-equilibrium problem, which unifies its Hadamard and Levitin-Polyak well-posedness. Using the nonlinear scalarization function, we give some sufficient conditions to guarantee the existence of well-posedness for the symmetric vector quasi-equilibrium problem.

  2. What Can Be (and What Has Been) Learned from General Equilibrium Simulation Models of School Finance?

    Science.gov (United States)

    Nechyba, Thomas J.

    2003-01-01

    Synthesizes lessons from school finance research that employs computational structural models to investigate different policy proposals. Suggests that full equilibrium analysis may lead to outcomes that differ from those predicted by partial equilibrium models. (Contains 50 references and 47 notes.) (JOW)

  3. Non-perfect-fluid space-times in thermodynamic equilibrium and generalized Friedmann equations

    CERN Document Server

    Schatz, Konrad; Chrobok, Thoralf

    2014-01-01

    Assuming homogeneous and parallax-free space-times, in the case of thermodynamic equilibrium, we construct the energy-momentum tensor of non-perfect fluids. To this end we derive the constitutive equations for energy density, isotropic and anisotropic pressure as well as heat-flux from the respective propagation equations. This provides these quantities in closed form, i. e. in terms of the structure constants of the three-dimensional isometry group of homogeneity and, respectively, of the kinematical quantities expansion, rotation and acceleration. Using Einstein's equations, the thereby occurring constants of integration can be determined such that one gets bounds on the kinematical quantities and finds a generalized form of the Friedmann equations. As a consequence, it is shown that, e. g., for a perfect fluid the Friedmann and G\\"odel models can be recovered. All this is derived without assuming any equations of state or other specific thermodynamic conditions, and, in principle, allows one to go beyond t...

  4. Regional disaster impact analysis: comparing input-output and computable general equilibrium models

    Science.gov (United States)

    Koks, Elco E.; Carrera, Lorenzo; Jonkeren, Olaf; Aerts, Jeroen C. J. H.; Husby, Trond G.; Thissen, Mark; Standardi, Gabriele; Mysiak, Jaroslav

    2016-08-01

    A variety of models have been applied to assess the economic losses of disasters, of which the most common ones are input-output (IO) and computable general equilibrium (CGE) models. In addition, an increasing number of scholars have developed hybrid approaches: one that combines both or either of them in combination with noneconomic methods. While both IO and CGE models are widely used, they are mainly compared on theoretical grounds. Few studies have compared disaster impacts of different model types in a systematic way and for the same geographical area, using similar input data. Such a comparison is valuable from both a scientific and policy perspective as the magnitude and the spatial distribution of the estimated losses are born likely to vary with the chosen modelling approach (IO, CGE, or hybrid). Hence, regional disaster impact loss estimates resulting from a range of models facilitate better decisions and policy making. Therefore, this study analyses the economic consequences for a specific case study, using three regional disaster impact models: two hybrid IO models and a CGE model. The case study concerns two flood scenarios in the Po River basin in Italy. Modelling results indicate that the difference in estimated total (national) economic losses and the regional distribution of those losses may vary by up to a factor of 7 between the three models, depending on the type of recovery path. Total economic impact, comprising all Italian regions, is negative in all models though.

  5. The economic impact of restricted water supply: a computable general equilibrium analysis.

    Science.gov (United States)

    Berrittella, Maria; Hoekstra, Arjen Y; Rehdanz, Katrin; Roson, Roberto; Tol, Richard S J

    2007-04-01

    Water problems are typically studied at the level of the river catchment. About 70% of all water is used for agriculture, and agricultural products are traded internationally. A full understanding of water use is impossible without understanding the international market for food and related products, such as textiles. The water embedded in commodities is called virtual water. Based on a general equilibrium model, we offer a method for investigating the role of water resources and water scarcity in the context of international trade. We run five alternative scenarios, analyzing the effects of water scarcity due to reduced availability of groundwater. This can be a consequence of physical constraints, and of policies curbing water demand. Four scenarios are based on a "market solution", where water owners can capitalize their water rent or taxes are recycled. In the fifth "non-market" scenario, this is not the case; supply restrictions imply productivity losses. Restrictions in water supply would shift trade patterns of agriculture and virtual water. These shifts are larger if the restriction is larger, and if the use of water in production is more rigid. Welfare losses are substantially larger in the non-market situation. Water-constrained agricultural producers lose, but unconstrained agricultural produces gain; industry gains as well. As a result, there are regional winners and losers from water supply constraints. Because of the current distortions of agricultural markets, water supply constraints could improve allocative efficiency; this welfare gain may more than offset the welfare losses due to the resource constraint.

  6. Economic consequences of aviation system disruptions: A reduced-form computable general equilibrium analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhenhua; Rose, Adam Z.; Prager, Fynnwin; Chatterjee, Samrat

    2017-01-01

    The state of the art approach to economic consequence analysis (ECA) is computable general equilibrium (CGE) modeling. However, such models contain thousands of equations and cannot readily be incorporated into computerized systems used by policy analysts to yield estimates of economic impacts of various types of transportation system failures due to natural hazards, human related attacks or technological accidents. This paper presents a reduced-form approach to simplify the analytical content of CGE models to make them more transparent and enhance their utilization potential. The reduced-form CGE analysis is conducted by first running simulations one hundred times, varying key parameters, such as magnitude of the initial shock, duration, location, remediation, and resilience, according to a Latin Hypercube sampling procedure. Statistical analysis is then applied to the “synthetic data” results in the form of both ordinary least squares and quantile regression. The analysis yields linear equations that are incorporated into a computerized system and utilized along with Monte Carlo simulation methods for propagating uncertainties in economic consequences. Although our demonstration and discussion focuses on aviation system disruptions caused by terrorist attacks, the approach can be applied to a broad range of threat scenarios.

  7. AGRICULTURAL GROWTH AND POVERTY REDUCTION IN THE D.R.CONGO: A GENERAL EQUILIBRIUM APPROACH

    Directory of Open Access Journals (Sweden)

    James Wabenga Yango

    2016-04-01

    Full Text Available This paper evaluates the contribution of agricultural growth to poverty reduction in the D.R.Congo over the projection period 2013 - 2020. It raises questions over the investment options to sustain such growth effort. We use a recursive dynamic computable general equilibrium model combine with survey-based micro simulation analysis at both national and subnational levels. We assume in the simulations that the additional growth in total factor productivity is an exogenous factor and find the following results. First, we find that 8.21 % agricultural annual growth rate is more effective at reducing poverty and achieves the goal of halving poverty by 2020. Second, we identify agricultural investment priorities and the required levels of public spending to achieve such growth and poverty reduction goals. We further analyze the growth at the subsector level and find that cereals and roots are more pro-poor. From this perspective, agricultural strategy based on expanding food crops production should be afforded the highest priority.

  8. Computable general equilibrium modelling in the context of trade and environmental policy

    Energy Technology Data Exchange (ETDEWEB)

    Koesler, Simon Tobias

    2014-10-14

    This thesis is dedicated to the evaluation of environmental policies in the context of climate change. Its objectives are twofold. Its first part is devoted to the development of potent instruments for quantitative impact analysis of environmental policy. In this context, the main contributions include the development of a new computable general equilibrium (CGE) model which makes use of the new comprehensive and coherent World Input-Output Dataset (WIOD) and which features a detailed representation of bilateral and bisectoral trade flows. Moreover it features an investigation of input substitutability to provide modellers with adequate estimates for key elasticities as well as a discussion and amelioration of the standard base year calibration procedure of most CGE models. Building on these tools, the second part applies the improved modelling framework and studies the economic implications of environmental policy. This includes an analysis of so called rebound effects, which are triggered by energy efficiency improvements and reduce their net benefit, an investigation of how firms restructure their production processes in the presence of carbon pricing mechanisms, and an analysis of a regional maritime emission trading scheme as one of the possible options to reduce emissions of international shipping in the EU context.

  9. Discharge Fee Policy Analysis: A Computable General Equilibrium (CGE Model of Water Resources and Water Environments

    Directory of Open Access Journals (Sweden)

    Guohua Fang

    2016-09-01

    Full Text Available To alleviate increasingly serious water pollution and shortages in developing countries, various kinds of policies have been implemented by local governments. It is vital to quantify and evaluate the performance and potential economic impacts of these policies. This study develops a Computable General Equilibrium (CGE model to simulate the regional economic and environmental effects of discharge fees. Firstly, water resources and water environment factors are separated from the input and output sources of the National Economic Production Department. Secondly, an extended Social Accounting Matrix (SAM of Jiangsu province is developed to simulate various scenarios. By changing values of the discharge fees (increased by 50%, 100% and 150%, three scenarios are simulated to examine their influence on the overall economy and each industry. The simulation results show that an increased fee will have a negative impact on Gross Domestic Product (GDP. However, waste water may be effectively controlled. Also, this study demonstrates that along with the economic costs, the increase of the discharge fee will lead to the upgrading of industrial structures from a situation of heavy pollution to one of light pollution which is beneficial to the sustainable development of the economy and the protection of the environment.

  10. Impacts Of External Price Shocks On Malaysian Macro Economy-An Applied General Equilibrium Analysis

    Directory of Open Access Journals (Sweden)

    Abul Quasem Al-Amin

    2008-10-01

    Full Text Available This paper examines the impacts of external price shocks in the Malaysian economy. There are three simulations are carried out with different degrees of external shocks using Malaysian Social Accounting Matrix (SAM and Computable General Equilibrium (CGE analysis. The model results indicate that the import price shocks, better known as external price shocks by 15% decreases the domestic production of building and construction sector by 25.87%, hotels, restaurants and entertainment sector by 12.04%, industry sector by 12.02%, agriculture sector by 11.01%, and electricity and gas sector by 9.55% from the baseline. On the import side, our simulation results illustrate that as a result of the import price shocks by 15%, imports decreases significantly in all sectors from base level. Among the scenarios, the largest negative impacts goes on industry sectors by 29.67% followed by building and construction sector by 22.42%, hotels, restaurants and entertainment sector by 19.45%, electricity and gas sector by 13.%, agriculture sector by 12.63% and other service sectors by 11.17%. However significant negative impact goes to the investment and fixed capital investment. It also causes the household income, household consumption and household savings down and increases the cost of livings in the economy results in downward social welfare.

  11. Computable General Equilibrium Model Fiscal Year 2013 Capability Development Report - April 2014

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Brian Keith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). National Infrastructure Simulation and Analysis Center (NISAC); Rivera, Michael K. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). National Infrastructure Simulation and Analysis Center (NISAC); Boero, Riccardo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). National Infrastructure Simulation and Analysis Center (NISAC)

    2014-04-01

    This report documents progress made on continued developments of the National Infrastructure Simulation and Analysis Center (NISAC) Computable General Equilibrium Model (NCGEM), developed in fiscal year 2012. In fiscal year 2013, NISAC the treatment of the labor market and tests performed with the model to examine the properties of the solutions computed by the model. To examine these, developers conducted a series of 20 simulations for 20 U.S. States. Each of these simulations compared an economic baseline simulation with an alternative simulation that assumed a 20-percent reduction in overall factor productivity in the manufacturing industries of each State. Differences in the simulation results between the baseline and alternative simulations capture the economic impact of the reduction in factor productivity. While not every State is affected in precisely the same way, the reduction in manufacturing industry productivity negatively affects the manufacturing industries in each State to an extent proportional to the reduction in overall factor productivity. Moreover, overall economic activity decreases when manufacturing sector productivity is reduced. Developers ran two additional simulations: (1) a version of the model for the State of Michigan, with manufacturing divided into two sub-industries (automobile and other vehicle manufacturing as one sub-industry and the rest of manufacturing as the other subindustry); and (2) a version of the model for the United States, divided into 30 industries. NISAC conducted these simulations to illustrate the flexibility of industry definitions in NCGEM and to examine the simulation properties of in more detail.

  12. The economic impacts of the September 11 terrorist attacks: a computable general equilibrium analysis

    Energy Technology Data Exchange (ETDEWEB)

    Oladosu, Gbadebo A [ORNL; Rose, Adam [University of Southern California, Los Angeles; Bumsoo, Lee [University of Illinois; Asay, Gary [University of Southern California

    2009-01-01

    This paper develops a bottom-up approach that focuses on behavioral responses in estimating the total economic impacts of the September 11, 2001, World Trade Center (WTC) attacks. The estimation includes several new features. First, is the collection of data on the relocation of firms displaced by the attack, the major source of resilience in muting the direct impacts of the event. Second, is a new estimate of the major source of impacts off-site -- the ensuing decline of air travel and related tourism in the U.S. due to the social amplification of the fear of terrorism. Third, the estimation is performed for the first time using Computable General Equilibrium (CGE) analysis, including a new approach to reflecting the direct effects of external shocks. This modeling framework has many advantages in this application, such as the ability to include behavioral responses of individual businesses and households, to incorporate features of inherent and adaptive resilience at the level of the individual decision maker and the market, and to gauge quantity and price interaction effects across sectors of the regional and national economies. We find that the total business interruption losses from the WTC attacks on the U.S. economy were only slightly over $100 billion, or less than 1.0% of Gross Domestic Product. The impacts were only a loss of $14 billion of Gross Regional Product for the New York Metropolitan Area.

  13. An AI Embedded Object-Oriented Approach for Formulating Computable General Equilibrium

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper proposes and illustrates an AI embedded object-oriented methodology to formulate the computable general equilibrium (CGE) models.In this framework,a CGE model is viewed as a collection of objects embedded AI or namely agents in computer world,corresponding to economic agents and entities in real world,such as government,households,markets and so on.A frame representation of major objects in CGE model is used for trade and environment.Embedded AI object-oriented approach(or software agent)is used in the CGE model representation can able to narrow the gap among the semantic representation,formal CGE (mathematical) representation and computer and algorithm representation,and to improve CGE in understanding and maintenance etc.In such a system,constructing a CGE model to appear an intuitive process rather than an abstract process.This intuitive process needs more understanding of the substance of economics and the logic underlying the problem rather than mathematical notation.

  14. Generalized quantum master equations in and out of equilibrium: When can one win?

    Science.gov (United States)

    Kelly, Aaron; Montoya-Castillo, Andrés; Wang, Lu; Markland, Thomas E.

    2016-05-01

    Generalized quantum master equations (GQMEs) are an important tool in modeling chemical and physical processes. For a large number of problems, it has been shown that exact and approximate quantum dynamics methods can be made dramatically more efficient, and in the latter case more accurate, by proceeding via the GQME formalism. However, there are many situations where utilizing the GQME approach with an approximate method has been observed to return the same dynamics as using that method directly. Here, for systems both in and out of equilibrium, we provide a more detailed understanding of the conditions under which using an approximate method can yield benefits when combined with the GQME formalism. In particular, we demonstrate the necessary manipulations, which are satisfied by exact quantum dynamics, that are required to recast the memory kernel in a form that can be analytically shown to yield the same result as a direct application of the dynamics regardless of the approximation used. By considering the connections between these forms of the kernel, we derive the conditions that approximate methods must satisfy if they are to offer different results when used in conjunction with the GQME formalism. These analytical results thus provide new insights as to when proceeding via the GQME approach can be used to improve the accuracy of simulations.

  15. Three-Dimensional General-Relativistic Hydrodynamic Simulations of Binary Neutron Star Coalescence and Stellar Collapse with Multipatch Grids

    CERN Document Server

    Reisswig, C; Ott, C D; Abdikamalov, E; Moesta, P; Pollney, D; Schnetter, E

    2013-01-01

    We present a new three-dimensional general-relativistic hydrodynamic evolution scheme coupled to dynamical spacetime evolutions which is capable of efficiently simulating stellar collapse, isolated neutron stars, black hole formation, and binary neutron star coalescence. We make use of a set of adapted curvi-linear grids (multipatches) coupled with flux-conservative cell-centered adaptive mesh refinement. This allows us to significantly enlarge our computational domains while still maintaining high resolution in the gravitational-wave extraction zone, the exterior layers of a star, or the region of mass ejection in merging neutron stars. The fluid is evolved with a high-resolution shock capturing finite volume scheme, while the spacetime geometry is evolved using fourth-order finite differences. We employ a multi-rate Runge-Kutta time integration scheme for efficiency, evolving the fluid with second-order and the spacetime geometry with fourth-order integration, respectively. We validate our code by a number ...

  16. Analytical computation of the Mercury perihelion precession via the relativistic gravitational law and comparison with general relativity

    CERN Document Server

    Fokas, Athanassios S; Grigoriou, D

    2015-01-01

    Let $r(\\varphi)$ denote the orbit of Mercury and other planets. We compare the formula of General Relativity (GR) for $r(\\varphi)$, as well as the formula for the corresponding perihelion precession angle $\\Delta \\varphi$, with the formulae obtained via the relativistic gravitational law, $F=GMm\\gamma^3/r^2$. The latter law can be derived from Newton's gravitational law by employing the gravitational rather than the rest mass of the rotating body and using special relativity (SR) together with the equivalence principle to compute the inertial and hence the gravitational, mass. Remarkably, it is found that the two expressions for $r(\\varphi)$ differ only by a factor of 2 and by an additive constant. This constant does not affect the formula for the $\\Delta \\varphi$, thus the two expressions for $\\Delta\\varphi$ differ only by a factor of 2.

  17. The mineral sector and economic development in Ghana: A computable general equilibrium analysis

    Science.gov (United States)

    Addy, Samuel N.

    A computable general equilibrium model (CGE) model is formulated for conducting mineral policy analysis in the context of national economic development for Ghana. The model, called GHANAMIN, places strong emphasis on production, trade, and investment. It can be used to examine both micro and macro economic impacts of policies associated with mineral investment, taxation, and terms of trade changes, as well as mineral sector performance impacts due to technological change or the discovery of new deposits. Its economywide structure enables the study of broader development policy with a focus on individual or multiple sectors, simultaneously. After going through a period of contraction for about two decades, mining in Ghana has rebounded significantly and is currently the main foreign exchange earner. Gold alone contributed 44.7 percent of 1994 total export earnings. GHANAMIN is used to investigate the economywide impacts of mineral tax policies, world market mineral prices changes, mining investment, and increased mineral exports. It is also used for identifying key sectors for economic development. Various simulations were undertaken with the following results: Recently implemented mineral tax policies are welfare increasing, but have an accompanying decrease in the output of other export sectors. World mineral price rises stimulate an increase in real GDP; however, this increase is less than real GDP decreases associated with price declines. Investment in the non-gold mining sector increases real GDP more than investment in gold mining, because of the former's stronger linkages to the rest of the economy. Increased mineral exports are very beneficial to the overall economy. Foreign direct investment (FDI) in mining increases welfare more so than domestic capital, which is very limited. Mining investment and the increased mineral exports since 1986 have contributed significantly to the country's economic recovery, with gold mining accounting for 95 percent of the

  18. General properties of the radiation spectra from relativistic electrons moving in a Langmuir turbulence

    CERN Document Server

    Teraki, Yuto

    2014-01-01

    We examine the radiation spectra from relativistic electrons moving in a Langmuir turbulence expected to exist in high energy astrophysical objects by using numerical method. The spectral shape is characterized by the spatial scale {\\lambda}, field strength {\\sigma}, and frequency of the Langmuir waves, and in term of frequency they are represented by {\\omega}_0 = 2{\\pi}c/{\\lambda}, {\\omega}_st = e{\\sigma}/mc, and {\\omega}_p, respectively. We normalize {\\omega}_st and {\\omega}_p by {\\omega}_0 as \\a \\equiv {\\omega}_st/{\\omega}_0 and \\b \\equiv{\\omega}_p/{\\omega}_0, and examine the spectral shape in the a-b plane. An earlier study based on Diffusive Radiation in Langmuir turbulence (DRL) theory by Fleishman and Toptygin showed that the typical frequency is {\\gamma}^2{\\omega}_p and that the low frequency spectrum behaves as F_{\\omega} pronto {\\omega}^1 for b > 1 irrespective of a. Here, we adopt the first principle numerical approach to obtain the radiation spectra in more detail. We generate Langmuir turbulence ...

  19. A class of exact isotropic solutions of Einstein's equations and relativistic stellar models in general relativity

    Science.gov (United States)

    Murad, Mohammad Hassan; Pant, Neeraj

    2014-03-01

    In this paper we have studied a particular class of exact solutions of Einstein's gravitational field equations for spherically symmetric and static perfect fluid distribution in isotropic coordinates. The Schwarzschild compactness parameter, GM/ c 2 R, can attain the maximum value 0.1956 up to which the solution satisfies the elementary tests of physical relevance. The solution also found to have monotonic decreasing adiabatic sound speed from the centre to the boundary of the fluid sphere. A wide range of fluid spheres of different mass and radius for a given compactness is possible. The maximum mass of the fluid distribution is calculated by using stellar surface density as parameter. The values of different physical variables obtained for some potential strange star candidates like Her X-1, 4U 1538-52, LMC X-4, SAX J1808.4-3658 given by our analytical model demonstrate the astrophysical significance of our class of relativistic stellar models in the study of internal structure of compact star such as self-bound strange quark star.

  20. General relativistic considerations of the field shedding model of fast radio bursts

    Science.gov (United States)

    Punsly, Brian; Bini, Donato

    2016-06-01

    Popular models of fast radio bursts (FRBs) involve the gravitational collapse of neutron star progenitors to black holes. It has been proposed that the shedding of the strong neutron star magnetic field (B) during the collapse is the power source for the radio emission. Previously, these models have utilized the simplicity of the Schwarzschild metric which has the restriction that the magnetic flux is magnetic `hair' that must be shed before final collapse. But neutron stars have angular momentum and charge and a fully relativistic Kerr-Newman solution exists in which B has its source inside of the event horizon. In this Letter, we consider the magnetic flux to be shed as a consequence of the electric discharge of a metastable collapsed state of a Kerr-Newman black hole. It has also been argued that the shedding model will not operate due to pair creation. By considering the pulsar death line, we find that for a neutron star with B = 1011-1013 G and a long rotation period, >1s this is not a concern. We also discuss the observational evidence supporting the plausibility of magnetic flux shedding models of FRBs that are spawned from rapidly rotating progenitors.

  1. General Relativistic Considerations of the Field Shedding Model of Fast Radio Bursts

    CERN Document Server

    Punsly, Brian

    2016-01-01

    Popular models of fast radio bursts (FRBs) involve the gravitational collapse of neutron star progenitors to black holes. It has been proposed that the shedding of the strong neutron star magnetic field ($B$) during the collapse is the power source for the radio emission. Previously, these models have utilized the simplicity of the Schwarzschild metric which has the restriction that the magnetic flux is magnetic "hair" that must be shed before final collapse. But, neutron stars have angular momentum and charge and a fully relativistic Kerr Newman solution exists in which $B$ has its source inside of the event horizon. In this letter, we consider the magnetic flux to be shed as a consequence of the electric discharge of a metastable collapsed state of a Kerr Newman black hole. It has also been argued that the shedding model will not operate due to pair creation. By considering the pulsar death line, we find that for a neutron star with $B = 10^{11} - 10^{13}$ G and a long rotation period, $>1$ s this is not a ...

  2. Exact power series solutions of the structure equations of the general relativistic isotropic fluid stars with linear barotropic and polytropic equations of state

    Science.gov (United States)

    Harko, T.; Mak, M. K.

    2016-09-01

    Obtaining exact solutions of the spherically symmetric general relativistic gravitational field equations describing the interior structure of an isotropic fluid sphere is a long standing problem in theoretical and mathematical physics. The usual approach to this problem consists mainly in the numerical investigation of the Tolman-Oppenheimer-Volkoff and of the mass continuity equations, which describes the hydrostatic stability of the dense stars. In the present paper we introduce an alternative approach for the study of the relativistic fluid sphere, based on the relativistic mass equation, obtained by eliminating the energy density in the Tolman-Oppenheimer-Volkoff equation. Despite its apparent complexity, the relativistic mass equation can be solved exactly by using a power series representation for the mass, and the Cauchy convolution for infinite power series. We obtain exact series solutions for general relativistic dense astrophysical objects described by the linear barotropic and the polytropic equations of state, respectively. For the polytropic case we obtain the exact power series solution corresponding to arbitrary values of the polytropic index n. The explicit form of the solution is presented for the polytropic index n=1, and for the indexes n=1/2 and n=1/5, respectively. The case of n=3 is also considered. In each case the exact power series solution is compared with the exact numerical solutions, which are reproduced by the power series solutions truncated to seven terms only. The power series representations of the geometric and physical properties of the linear barotropic and polytropic stars are also obtained.

  3. Are Equity and Efficiency Irreconcilable Goals in Education? A General Equilibrium Analysis of Basic Education Finance in China

    Science.gov (United States)

    Ding, Weili; Lu, Ming

    2007-01-01

    Lacking guidance of general equilibrium (GE) theories in public economics and the corresponding proper mechanisms, China has not surprisingly witnessed an inequality in educational expenditures across regions as well as insufficiency of funds for education in poor areas. It is wrongly thought that what happens is due to the decentralized financing…

  4. Strong convergence theorem for a generalized equilibrium problem and a κ-strict pseudocontraction in Hilbert spaces

    Institute of Scientific and Technical Information of China (English)

    Shi-sheng ZHANG; Ruo-feng RAO; Jia-lin HUANG

    2009-01-01

    The main purpose of this paper is to study a new iterative algorithm for finding a common element of the set of solutions for a generalized equilibrium problem and the set of fixed points for a κ-strict pseudocontractive mapping in the Hilbert space.The presented results extend and improve the corresponding results reported in the literature.

  5. Are Equity and Efficiency Irreconcilable Goals in Education? A General Equilibrium Analysis of Basic Education Finance in China

    Science.gov (United States)

    Ding, Weili; Lu, Ming

    2007-01-01

    Lacking guidance of general equilibrium (GE) theories in public economics and the corresponding proper mechanisms, China has not surprisingly witnessed an inequality in educational expenditures across regions as well as insufficiency of funds for education in poor areas. It is wrongly thought that what happens is due to the decentralized financing…

  6. The General Equilibrium Impact of Alternative Antipoverty Strategies: Income Maintenance, Training and Job Creation. Discussion Papers 386-77.

    Science.gov (United States)

    Bishop, John H.

    This paper attempts to provide a general equilibrium framework for comparing the merits of alternative methods of raising the income of the employable poor. The strategy is to specify a complete and interacting set of factor markets, parameterize alternative program types in a manner convenient to this specification, and then solve the system of…

  7. Relativistic generalization of the incentive trap of interstellar travel with application to Breakthrough Starshot

    Science.gov (United States)

    Heller, René

    2017-09-01

    As new concepts of sending interstellar spacecraft to the nearest stars are now being investigated by various research teams, crucial questions about the timing of such a vast financial and labour investment arise. If humanity could build high-speed interstellar lightsails and reach α Centauri 20 yr after launch, would it be better to wait a few years, then take advantage of further technology improvements and arrive earlier despite waiting? The risk of being overtaken by a future, faster probe has been described earlier as the incentive trap. Based on 211 yr of historical data, we find that the speed growth of artificial vehicles, from steam-driven locomotives to Voyager 1, is much faster than previously believed, about 4.72 per cent annually or a doubling every 15 yr. We derive the mathematical framework to calculate the minimum of the wait time to launch t plus travel time τ(t) and extend it into the relativistic regime. We show that the t + τ(t) minimum disappears for nearby targets. There is no use of waiting once we can reach an object within about 20 yr of travel, irrespective of the actual speed. In terms of speed, the t + τ(t) minimum for a travel to α Centauri occurs at 19.6 per cent the speed of light (c), in agreement with the 20 per cent c proposed by the Breakthrough Starshot initiative. If interstellar travel at 20 per cent c could be achieved within 45 yr from today and the kinetic energy be increased at a rate consistent with the historical record, then humans can reach the 10 most nearby stars within 100 yr from today.

  8. Trans Pacific Stategic Economic Partnership With Japan, South Korea and China Integrate: General Equilibrium Approach

    Directory of Open Access Journals (Sweden)

    Todsadee Areerat

    2012-01-01

    Full Text Available Problem statement: The Trans-Pacific Strategic Economic Partnership Agreement (TPP is a high standard and broad based Free Trade Agreement that aims to integrate the economies of the Asia-Pacific region. Recently, the US is pressing Japan to join the group. Japan is considering joining the TPP because of the dual considerations of its own economy and the political situation in East Asia. While, South Korea has yet to agree to join the TPP over concerns that their agriculture will be seriously affected. In addition, Japan and the US are employing both military and economic strategies to isolate China. However, China has contacted those already participating in TPP negotiations and shares some common views with Japan and South Korea on agricultural issues. Therefore, in this study, we attempt to assess the possibility of reaching full trade liberalization or trade creation through the TPP with the addition of new member countries including Japan, Korea and China. Approach: A Computable General Equilibrium (CGE or Global Trade Analysis Project (GTAP model is used to evaluate the economic effects of a TPP agreement among TPP countries with trade creation. In this study, seven cases were created to distinguish the welfare and trade effects of policy changes. Results: We found that the new member countries among TPP countries with East Asia countries including Japan, South Korea and China would benefit from the FTA among member countries. They gain much more from the real GDP and welfare than the TPP agreement, particularly Vietnam and Korea. This is particularly a fact for trade in the meat product sectors between TPP with Japan, Korea and China, which most of them gain benefit. Conclusion: Therefore, the TPP would benefit both economies and welfare with the eliminate tariff rate.

  9. Modeling the economic costs of disasters and recovery: analysis using a dynamic computable general equilibrium model

    Science.gov (United States)

    Xie, W.; Li, N.; Wu, J.-D.; Hao, X.-L.

    2014-04-01

    Disaster damages have negative effects on the economy, whereas reconstruction investment has positive effects. The aim of this study is to model economic causes of disasters and recovery involving the positive effects of reconstruction activities. Computable general equilibrium (CGE) model is a promising approach because it can incorporate these two kinds of shocks into a unified framework and furthermore avoid the double-counting problem. In order to factor both shocks into the CGE model, direct loss is set as the amount of capital stock reduced on the supply side of the economy; a portion of investments restores the capital stock in an existing period; an investment-driven dynamic model is formulated according to available reconstruction data, and the rest of a given country's saving is set as an endogenous variable to balance the fixed investment. The 2008 Wenchuan Earthquake is selected as a case study to illustrate the model, and three scenarios are constructed: S0 (no disaster occurs), S1 (disaster occurs with reconstruction investment) and S2 (disaster occurs without reconstruction investment). S0 is taken as business as usual, and the differences between S1 and S0 and that between S2 and S0 can be interpreted as economic losses including reconstruction and excluding reconstruction, respectively. The study showed that output from S1 is found to be closer to real data than that from S2. Economic loss under S2 is roughly 1.5 times that under S1. The gap in the economic aggregate between S1 and S0 is reduced to 3% at the end of government-led reconstruction activity, a level that should take another four years to achieve under S2.

  10. The economic impact of more sustainable water use in agriculture: A computable general equilibrium analysis

    Science.gov (United States)

    Calzadilla, Alvaro; Rehdanz, Katrin; Tol, Richard S. J.

    2010-04-01

    SummaryAgriculture is the largest consumer of freshwater resources - around 70 percent of all freshwater withdrawals are used for food production. These agricultural products are traded internationally. A full understanding of water use is, therefore, impossible without understanding the international market for food and related products, such as textiles. Based on the global general equilibrium model GTAP-W, we offer a method for investigating the role of green (rain) and blue (irrigation) water resources in agriculture and within the context of international trade. We use future projections of allowable water withdrawals for surface water and groundwater to define two alternative water management scenarios. The first scenario explores a deterioration of current trends and policies in the water sector (water crisis scenario). The second scenario assumes an improvement in policies and trends in the water sector and eliminates groundwater overdraft world-wide, increasing water allocation for the environment (sustainable water use scenario). In both scenarios, welfare gains or losses are not only associated with changes in agricultural water consumption. Under the water crisis scenario, welfare not only rises for regions where water consumption increases (China, South East Asia and the USA). Welfare gains are considerable for Japan and South Korea, Southeast Asia and Western Europe as well. These regions benefit from higher levels of irrigated production and lower food prices. Alternatively, under the sustainable water use scenario, welfare losses not only affect regions where overdrafting is occurring. Welfare decreases in other regions as well. These results indicate that, for water use, there is a clear trade-off between economic welfare and environmental sustainability.

  11. Isobaric Molecular Dynamics Version of the Generalized Replica Exchange Method (gREM): Liquid-Vapor Equilibrium.

    Science.gov (United States)

    Małolepsza, Edyta; Secor, Maxim; Keyes, Tom

    2015-10-22

    A prescription for sampling isobaric generalized ensembles with molecular dynamics is presented and applied to the generalized replica exchange method (gREM), which was designed to simulate first-order phase transitions. The properties of the isobaric gREM ensemble are discussed, and a study is presented for the liquid-vapor equilibrium of the guest molecules given for gas hydrate formation with the mW water model. Phase diagrams, critical parameters, and a law of corresponding states are obtained.

  12. Relativistic Remnants of Non-Relativistic Electrons

    CERN Document Server

    Kashiwa, Taro

    2015-01-01

    Electrons obeying the Dirac equation are investigated under the non-relativistic $c \\mapsto \\infty$ limit. General solutions are given by derivatives of the relativistic invariant functions whose forms are different in the time- and the space-like region, yielding the delta function of $(ct)^2 - x^2$. This light-cone singularity does survive to show that the charge and the current density of electrons travel with the speed of light in spite of their massiveness.

  13. CO2, energy and economy interactions: A multisectoral, dynamic, computable general equilibrium model for Korea

    Science.gov (United States)

    Kang, Yoonyoung

    While vast resources have been invested in the development of computational models for cost-benefit analysis for the "whole world" or for the largest economies (e.g. United States, Japan, Germany), the remainder have been thrown together into one model for the "rest of the world." This study presents a multi-sectoral, dynamic, computable general equilibrium (CGE) model for Korea. This research evaluates the impacts of controlling COsb2 emissions using a multisectoral CGE model. This CGE economy-energy-environment model analyzes and quantifies the interactions between COsb2, energy and economy. This study examines interactions and influences of key environmental policy components: applied economic instruments, emission targets, and environmental tax revenue recycling methods. The most cost-effective economic instrument is the carbon tax. The economic effects discussed include impacts on main macroeconomic variables (in particular, economic growth), sectoral production, and the energy market. This study considers several aspects of various COsb2 control policies, such as the basic variables in the economy: capital stock and net foreign debt. The results indicate emissions might be stabilized in Korea at the expense of economic growth and with dramatic sectoral allocation effects. Carbon dioxide emissions stabilization could be achieved to the tune of a 600 trillion won loss over a 20 year period (1990-2010). The average annual real GDP would decrease by 2.10% over the simulation period compared to the 5.87% increase in the Business-as-Usual. This model satisfies an immediate need for a policy simulation model for Korea and provides the basic framework for similar economies. It is critical to keep the central economic question at the forefront of any discussion regarding environmental protection. How much will reform cost, and what does the economy stand to gain and lose? Without this model, the policy makers might resort to hesitation or even blind speculation. With

  14. Geodesics without differential equations: general relativistic calculations for introductory modern physics classes

    Energy Technology Data Exchange (ETDEWEB)

    Rowland, D R [Student Support Services, University of Queensland, Brisbane QLD 4072 (Australia)

    2006-01-01

    Introductory courses covering modern physics sometimes introduce some elementary ideas from general relativity, though the idea of a geodesic is generally limited to shortest Euclidean length on a curved surface of two spatial dimensions rather than extremal aging in spacetime. It is shown that Epstein charts provide a simple geometric picture of geodesics in one space and one time dimension and that for a hypothetical uniform gravitational field, geodesics are straight lines on a planar diagram. This means that the properties of geodesics in a uniform field can be calculated with only a knowledge of elementary geometry and trigonometry, thus making the calculation of some basic results of general relativity accessible to students even in an algebra-based survey course on physics.

  15. General relativistic simulations of compact binary mergers as engines of short gamma-ray bursts

    CERN Document Server

    Paschalidis, Vasileios

    2016-01-01

    Black hole - neutron star (BHNS) and neutron star - neutron star (NSNS) binaries are among the favored candidates for the progenitors of the black hole - disk systems that may be the engines powering short-hard gamma ray bursts. After almost two decades of simulations of binary NSNSs and BHNSs in full general relativity we are now beginning to understand the ingredients that may be necessary for these systems to launch incipient jets. Here, we review our current understanding, and summarize the surprises and lessons learned from state-of-the-art (magnetohydrodynamic) simulations in full general relativity of BHNS and NSNS mergers as jet engines for short-hard gamma-ray bursts.

  16. Connecting Solubility, Equilibrium, and Periodicity in a Green, Inquiry Experiment for the General Chemistry Laboratory

    Science.gov (United States)

    Cacciatore, Kristen L.; Amado, Jose; Evans, Jason J.; Sevian, Hannah

    2008-01-01

    We present a novel first-year chemistry laboratory experiment that connects solubility, equilibrium, and chemical periodicity concepts. It employs a unique format that asks students to replicate experiments described in different sample lab reports, each lacking some essential information, rather than follow a scripted procedure. This structure is…

  17. Using the Science Writing Heuristic to Improve Students' Understanding of General Equilibrium

    Science.gov (United States)

    Rudd, James A., II; Greenbowe, Thomas J.; Hand, Brian M.

    2007-01-01

    This study compared the performance of students using the Science Writing Heuristic (SWH) approach and students using a standard or traditional laboratory curriculum on lecture exams and a laboratory practical exam on a specific topic, chemical equilibrium. The SWH helps students do inquiry science laboratory work by structuring the laboratory…

  18. Connecting Solubility, Equilibrium, and Periodicity in a Green, Inquiry Experiment for the General Chemistry Laboratory

    Science.gov (United States)

    Cacciatore, Kristen L.; Amado, Jose; Evans, Jason J.; Sevian, Hannah

    2008-01-01

    We present a novel first-year chemistry laboratory experiment that connects solubility, equilibrium, and chemical periodicity concepts. It employs a unique format that asks students to replicate experiments described in different sample lab reports, each lacking some essential information, rather than follow a scripted procedure. This structure is…

  19. On freeze-out problem in relativistic hydrodynamics

    CERN Document Server

    Ivanov, Yu B

    2008-01-01

    A finite unbound system which is equilibrium in one reference frame is in general nonequilibrium in another frame. This is a consequence of the relative character of the time synchronization in the relativistic physics. This puzzle was a prime motivation of the Cooper--Frye approach to the freeze-out in relativistic hydrodynamics. Solution of the puzzle reveals that the Cooper--Frye recipe is far not a unique phenomenological method that meets requirements of energy-momentum conservation. Alternative freeze-out recipes are considered and discussed.

  20. General relativistic simulations of compact binary mergers as engines for short gamma-ray bursts

    Science.gov (United States)

    Paschalidis, Vasileios

    2017-04-01

    Black hole—neutron star (BHNS) and neutron star—neutron star (NSNS) binaries are among the favored candidates for the progenitors of the black hole—disk systems that may be the engines powering short-hard gamma ray bursts. After almost two decades of simulations of binary NSNSs and BHNSs in full general relativity we are now beginning to understand the ingredients that may be necessary for these systems to launch incipient jets. Here, we review our current understanding, and summarize the surprises and lessons learned from state-of-the-art (magnetohydrodynamic) simulations in full general relativity of BHNS and NSNS mergers as jet engines for short-hard gamma-ray bursts. We also propose a new approach to probing the nuclear equation of state by virtue of multimessenger observations.

  1. General Relativistic Energy Conditions The Hubble expansion in the epoch of galaxy formation

    CERN Document Server

    Visser, M

    1997-01-01

    The energy conditions of Einstein gravity (classical general relativity) are designed to extract as much information as possible from classical general relativity without enforcing a particular equation of state for the stress-energy. This systematic avoidance of the need to specify a particular equation of state is particularly useful in a cosmological setting --- since the equation of state for the cosmological fluid in a Friedmann-Robertson-Walker type universe is extremely uncertain. I shall show that the energy conditions provide simple and robust bounds on the behaviour of both the density and look-back time as a function of red-shift. I shall show that current observations suggest that the so-called strong energy condition (SEC) is violated sometime between the epoch of galaxy formation and the present. This implies that no possible combination of ``normal'' matter is capable of fitting the observational data.

  2. Handbook of relativistic quantum chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wenjian (ed.) [Peking Univ., Beijing (China). Center for Computational Science and Engineering

    2017-03-01

    This handbook focuses on the foundations of relativistic quantum mechanics and addresses a number of fundamental issues never covered before in a book. For instance: How can many-body theory be combined with quantum electrodynamics? How can quantum electrodynamics be interfaced with relativistic quantum chemistry? What is the most appropriate relativistic many-electron Hamiltonian? How can we achieve relativistic explicit correlation? How can we formulate relativistic properties? - just to name a few. Since relativistic quantum chemistry is an integral component of computational chemistry, this handbook also supplements the ''Handbook of Computational Chemistry''. Generally speaking, it aims to establish the 'big picture' of relativistic molecular quantum mechanics as the union of quantum electrodynamics and relativistic quantum chemistry. Accordingly, it provides an accessible introduction for readers new to the field, presents advanced methodologies for experts, and discusses possible future perspectives, helping readers understand when/how to apply/develop the methodologies.

  3. Endogenous Capital Market Imperfection, Informal Interest Rate Determination and International Factor mobility in a General Equilibrium Model

    OpenAIRE

    Chaudhuri, Sarbajit; GUPTA, Manash Ranjan

    2013-01-01

    This paper makes a pioneering attempt to provide a theory of determination of interest rate in the informal credit market in a less developed economy in terms of a three-sector static deterministic general equilibrium model. There are two informal sectors which obtain production loans from a monopolistic moneylender and employ labour from the informal labour market. On the other hand, the formal sector employs labour at an institutionally fixed wage rate and takes loans from the competitive f...

  4. LINEAR GENERAL EQUILIBRIUM MODEL OF ENERGY DEMAND AND CO2 EMISSIONS GENERATED BY THE ANDALUSIAN PRODUCTIVE SYSTEM

    Directory of Open Access Journals (Sweden)

    Manuel Alejandro Cardenete

    2012-01-01

    Full Text Available In this study we apply a multiplier decomposition methodology of a linear general equilibrium model based on the regional social accounting matrix to the Andalusian economy. The aim of this methodology is to separate the size of the different effects in terms of energy expenditure and total emissions generated by the whole productive system to satisfy the final demand of each branch of the Andalusian economy and the direct emissions generated to produce energy for each subsystem.

  5. Viscosity-projection method for a family of general equilibrium problems and asymptotically strict pseudocontractions in the intermediate sense.

    Science.gov (United States)

    Wen, Dao-Jun

    2013-01-01

    In this paper, a Meir-Keeler contraction is introduced to propose a viscosity-projection approximation method for finding a common element of the set of solutions of a family of general equilibrium problems and the set of fixed points of asymptotically strict pseudocontractions in the intermediate sense. Strong convergence of the viscosity iterative sequences is obtained under some suitable conditions. Results presented in this paper extend and unify the previously known results announced by many other authors.

  6. Convergence Theorem for Generalized Mixed Equilibrium Problem and Common Fixed Point Problem for a Family of Multivalued Mappings

    Directory of Open Access Journals (Sweden)

    J. N. Ezeora

    2016-01-01

    Full Text Available In this paper, a new hybrid iterative algorithm is constructed using the shrinking projection method introduced by Takahashi. The sequence of the algorithm is proved to converge strongly to a common element of the set of solutions of generalized mixed equilibrium problem and the set of common fixed points of a finite family of multivalued strictly pseudocontractive mappings in real Hilbert spaces. Furthermore, we apply our main result to convex minimization problem.

  7. Going beyond the Kaiser redshift-space distortion formula: a full general relativistic account of the effects and their detectability in galaxy clustering

    CERN Document Server

    Yoo, Jaiyul; Seljak, Uros; Zaldarriaga, Matias

    2012-01-01

    Kaiser redshift-space distortion formula describes well the clustering of galaxies in redshift surveys on small scales, but there are numerous additional terms that arise on large scales. Some of these terms can be described using Newtonian dynamics and have been discussed in the literature, while the others require proper general relativistic description that was only recently developed. Accounting for these terms in galaxy clustering is the first step toward tests of general relativity on horizon scales. The effects can be classified as two terms that represent the velocity and the gravitational potential contributions. Their amplitude is determined by effects such as the volume and luminosity distance fluctuation effects and the time evolution of galaxy number density and Hubble parameter. We compare the Newtonian approximation often used in the redshift-space distortion literature to the fully general relativistic equation, and show that Newtonian approximation accounts for most of the terms contributing ...

  8. Applicability of Markets to Global Scheduling in Grids: Critical Examination of General Equilibrium Theory and Market Folklore

    Science.gov (United States)

    Nakai, Junko; VanDerWijngaart, Rob F.

    2003-01-01

    Markets are often considered superior to other global scheduling mechanisms for distributed computing systems. This claim is supported by: a casual observation from our every-day life that markets successfully equilibrate supply and demand, and the features of markets which originate in the general equilibrium theory, e.g., efficiency and the lack of necessity of 2 central controller. This paper describes why such beliefs in markets are not warranted. It does so by examining the general equilibrium theory, in terms of scope, abstraction, and interpretation. Not only does the general equilibrium theory fail to provide a satisfactory explanation of actual economies, including a computing-resource economy, it also falls short of supplying theoretical foundations for commonly held views of market desirability. This paper also points out that the argument for the desirability of markets involves circular reasoning and that the desirability can be established only vis-a-vis a scheduling goal. Finally, recasting the conclusion of Arrow's Impossibility Theorem as that for global scheduling, we conclude that there exists no market-based scheduler that is rational (in the sense defined in microeconomic theory), takes into account utility of more than one user, and yet yields a Pareto-optimal outcome for arbitrary user utility functions.

  9. Health and economic impacts of air pollution in China: a comparison of the general equilibrium approach and human capital approach.

    Science.gov (United States)

    Wan, Yue; Yang, Hong-Wei; Masui, Toshihiko

    2005-12-01

    In China, combustion of fossil fuels and biomass has produced serious air pollution that does harm to human health. Based on dose-response relationships derived from epidemiological studies, the authors calculated the number of deaths and people with health problems which were thought to be attributable to China's air pollution in the year of 2000. In order to estimate the corresponding economic impacts from the national point of view, the general equilibrium approach was selected as an analysis tool for this study. A computable general equilibrium (CGE) model was constructed involving 39 sectors and 32 commodities. The human capital approach (HCA) was also used for comparison. The economic burden of disease for people estimated by HCA was equivalent to 1.26 per thousand (ranging from 0.44 per thousand to 1.84 per thousand) of China's gross domestic product (GDP). China's GDP loss estimated by the general equilibrium approach reached 0.38 per thousand (ranging from 0.16 per thousand to 0.51 per thousand). The difference between the two approaches and the implications of the results were discussed.

  10. Health and Economic Impacts of Air Pollution in China: A Comparison of the General Equilibrium Approach and Human Capital Approach

    Institute of Scientific and Technical Information of China (English)

    YUE WAN; HONG-WEI YANG; TOSHIHIKO MASUI

    2005-01-01

    In China, combustion of fossil fuels and biomass has produced serious air pollution that does harm to human health. Based on dose-response relationships derived from epidemiological studies, the authors calculated the number of deaths and people with health problems which were thought to be attributable to China's air pollution in the year of 2000. In order to estimate the corresponding economic impacts from the national point of view, the general equilibrium approach was selected as an analysis tool for this study. A computable general equilibrium (CGE) model was constructed involving 39 sectors and 32 commodities.The human capital approach (HCA) was also used for comparison. The economic burden of disease for people estimated by HCA was equivalent to 1.26‰ (ranging from 0.44‰ to 1.84‰) of China's gross domestic product (GDP). China's GDP loss estimated by the general equilibrium approach reached 0.38‰ (ranging from 0.16‰ to 0.51‰). The difference between the two approaches and the implications of the results were discussed.

  11. A New Multi-Dimensional General Relativistic Neutrino Hydrodynamics Code for Core-Collapse Supernovae IV. The Neutrino Signal

    CERN Document Server

    Mueller, B

    2014-01-01

    Considering general relativistic, two-dimensional (2D) supernova (SN) explosion models of progenitor stars between 8.1 and 27 solar masses, we systematically analyze the properties of the neutrino emission from core collapse and bounce to the post-explosion phase. The models were computed with the Vertex-CoCoNuT code, using three-flavor, energy-dependent neutrino transport in the ray-by-ray-plus approximation. Our results confirm the close similarity of the mean energies of electron antineutrinos and heavy-lepton neutrinos and even their crossing during the accretion phase for stars with M>10 M_sun as observed in previous 1D and 2D simulations with state-of-the-art neutrino transport. We establish a roughly linear scaling of the electron antineutrino mean energy with the proto-neutron star (PNS) mass, which holds in time as well as for different progenitors. Convection inside the PNS affects the neutrino emission on the 10-20% level, and accretion continuing beyond the onset of the explosion prevents the abru...

  12. Formation of Overheated Regions and Truncated Disks around Black Holes; Three-dimensional General Relativistic Radiation-magnetohydrodynamics Simulations

    CERN Document Server

    Takahashi, Hiroyuki R; Kawashima, Tomohisa; Sekiguchi, Yuichiro

    2016-01-01

    Using three-dimensional general relativistic radiation magnetohydrodynamics simulations of accretion flows around stellar mass black holes, we report that the relatively cold disk ($\\gtrsim 10^{7}$K) is truncated near the black hole. Hot and less-dense regions, of which the gas temperature is $ \\gtrsim 10^9$K and more than ten times higher than the radiation temperature (overheated regions), appear within the truncation radius. The overheated regions also appear above as well as below the disk, and sandwich the cold disk, leading to the effective Compton upscattering. The truncation radius is $\\sim 30 r_{\\rm g}$ for $\\dot{M} \\sim L_{\\rm Edd}/c^2$, where $r_{\\rm g}, \\dot M, L_\\mathrm{Edd}, c$ are the gravitational radius, mass accretion rate, Eddington luminosity, and light speed. Our results are consistent with observations of very high state, whereby the truncated disk is thought to be embedded in the hot rarefied regions. The truncation radius shifts inward to $\\sim 10 r_{\\rm g}$ with increasing mass accret...

  13. Relativistic Self-similar Dynamic Collapses of Black Holes in General Polytropic Spherical Clouds

    CERN Document Server

    Lian, Biao

    2013-01-01

    We study the hydrodynamic self-similar mass collapses of general polytropic (GP) spherical clouds to central Schwarzschild black holes and void evolution with or without shocks. In order to grossly capture characteristic effects of general relativity (GR) outside yet close to the event horizon of a Schwarzschild black hole and to avoid mathematical complexity, we adopt the approximation of the Paczynski-Wiita gravity to replace the simple Newtonian gravity in our model formulation. A new dimensionless parameter s appears with the physical meaning of the square of the ratio of the sound speed to the speed of light $c$. Various self-similar dynamic solutions are constructed for a polytropic index $\\gamma>4/3$. Two (for small enough $s4/3$, representing the collapse of static singular GP spheres towards the central singularity of spacetime. Such GP spherical dynamic mass collapse is shown to be highly efficient for the rapid formation of supermassive black holes (SMBHs; mass range of $10^6-10^{10}M_{\\odot}$) in ...

  14. Relativistic quantum revivals.

    Science.gov (United States)

    Strange, P

    2010-03-26

    Quantum revivals are now a well-known phenomena within nonrelativistic quantum theory. In this Letter we display the effects of relativity on revivals and quantum carpets. It is generally believed that revivals do not occur within a relativistic regime. Here we show that while this is generally true, it is possible, in principle, to set up wave packets with specific mathematical properties that do exhibit exact revivals within a fully relativistic theory.

  15. A GENERAL RELATIVISTIC NULL HYPOTHESIS TEST WITH EVENT HORIZON TELESCOPE OBSERVATIONS OF THE BLACK HOLE SHADOW IN Sgr A*

    Energy Technology Data Exchange (ETDEWEB)

    Psaltis, Dimitrios; Özel, Feryal; Chan, Chi-Kwan; Marrone, Daniel P. [Astronomy Department, University of Arizona, 933 N. Cherry Ave, Tucson, AZ 85721 (United States)

    2015-12-01

    The half opening angle of a Kerr black hole shadow is always equal to (5 ± 0.2)GM/Dc{sup 2}, where M is the mass of the black hole and D is its distance from the Earth. Therefore, measuring the size of a shadow and verifying whether it is within this 4% range constitutes a null hypothesis test of general relativity. We show that the black hole in the center of the Milky Way, Sgr A*, is the optimal target for performing this test with upcoming observations using the Event Horizon Telescope (EHT). We use the results of optical/IR monitoring of stellar orbits to show that the mass-to-distance ratio for Sgr A* is already known to an accuracy of ∼4%. We investigate our prior knowledge of the properties of the scattering screen between Sgr A* and the Earth, the effects of which will need to be corrected for in order for the black hole shadow to appear sharp against the background emission. Finally, we explore an edge detection scheme for interferometric data and a pattern matching algorithm based on the Hough/Radon transform and demonstrate that the shadow of the black hole at 1.3 mm can be localized, in principle, to within ∼9%. All these results suggest that our prior knowledge of the properties of the black hole, of scattering broadening, and of the accretion flow can only limit this general relativistic null hypothesis test with EHT observations of Sgr A* to ≲10%.

  16. Fully General Relativistic Simulations of Core-Collapse Supernovae with An Approximate Neutrino Transport

    CERN Document Server

    Kuroda, Takami; Takiwaki, Tomoya

    2012-01-01

    We present results from the first generation of multi-dimensional hydrodynamic core-collapse simulations in full general relativity (GR) that include an approximate treatment of neutrino transport. Using a M1 closure scheme with an analytic variable Eddington factor, we solve the energy-independent set of radiation energy and momentum based on the Thorne's momentum formalism. To simplify the source terms of the transport equations, a methodology of multiflavour neutrino leakage scheme is partly employed. Our newly developed code is designed to evolve the Einstein field equation together with the GR radiation hydrodynamic equations. We follow the dynamics starting from the onset of gravitational core-collapse of a 15 $M_{\\odot}$ star, through bounce, up to about 100 ms postbounce in this study to study how the spacial multi-dimensionality and GR would affect the dynamics in the early postbounce phase. Our 3D results support the anticipation in previous 1D results that the neutrino luminosity and average neutri...

  17. General relativistic models for rotating magnetized neutron stars in conformally flat space-time

    Science.gov (United States)

    Pili, A. G.; Bucciantini, N.; Del Zanna, L.

    2017-09-01

    The extraordinary energetic activity of magnetars is usually explained in terms of dissipation of a huge internal magnetic field of the order of 1015-16 G. How such a strong magnetic field can originate during the formation of a neutron star (NS) is still subject of active research. An important role can be played by fast rotation: if magnetars are born as millisecond rotators dynamo mechanisms may efficiently amplify the magnetic field inherited from the progenitor star during the collapse. In this case, the combination of rapid rotation and strong magnetic field determine the right physical condition not only for the development of a powerful jet-driven explosion, manifesting as a gamma-ray burst, but also for a copious gravitational waves emission. Strong magnetic fields are indeed able to induce substantial quadrupolar deformations in the star. In this paper, we analyse the joint effect of rotation and magnetization on the structure of a polytropic and axisymmetric NS, within the ideal magneto-hydrodynamic regime. We will consider either purely toroidal or purely poloidal magnetic field geometries. Through the sampling of a large parameter space, we generalize previous results in literature, inferring new quantitative relations that allow for a parametrization of the induced deformation, that takes into account also the effects due to the stellar compactness and the current distribution. Finally, in the case of purely poloidal field, we also discuss how different prescription on the surface charge distribution (a gauge freedom) modify the properties of the surrounding electrosphere and its physical implications.

  18. GRAVITAS : General Relativistic Astrophysics VIa Timing And Spectroscopy: An ESA M3 mission proposal

    CERN Document Server

    Nandra, Kirpal; Fabian, Andy; Strueder, Lothar; Willingale, Richard; Watson, Mike; Jonker, Peter; Kunieda, Hideyo; Miniutti, Giovanni; Motch, Christian; Predehl, Peter

    2011-01-01

    GRAVITAS is an X-ray observatory, designed and optimised to address the ESA Cosmic Vision theme of "Matter under extreme conditions". It was submitted as a response to the call for M3 mission proposals. The concept centres around an X-ray telescope of unprecedented effective area, which will focus radiation emitted from close to the event horizon of black holes or the surface of neutron stars. To reveal the nature and behaviour of matter in the most extreme astrophysical environments, GRAVITAS targets a key feature in the X-ray spectra of compact objects: the iron Kalpha line at ~6.5 keV. The energy, profile, and variability of this emission line, and the properties of the surrounding continuum emission, shaped by General Relativity (GR) effects, provide a unique probe of gravity in its strong field limit. Among its prime targets are hundreds of supermassive black holes in bright Active Galactic Nuclei (AGN), which form the perfect laboratory to help understand the physical processes behind black hole growth....

  19. Change in Minimum Orbit Intersection Distance due to General Relativistic Precession in Small Solar System Bodies

    Science.gov (United States)

    Sekhar, Aswin; Valsecchi, Giovanni B.; Asher, David; Werner, Stephanie; Vaubaillon, Jeremie; Li, Gongjie

    2017-06-01

    One of the greatest successes of Einstein's General Theory of Relativity (GR) was the correct prediction of the perihelion precession of Mercury. The closed form expression to compute this precession tells us that substantial GR precession would occur only if the bodies have a combination of both moderately small perihelion distance and semi-major axis. Minimum Orbit Intersection Distance (MOID) is a quantity which helps us to understand the closest proximity of two orbits in space. Hence evaluating MOID is crucial to understand close encounters and collision scenarios better. In this work, we look at the possible scenarios where a small GR precession in argument of pericentre can create substantial changes in MOID for small bodies ranging from meteoroids to comets and asteroids.Previous works have looked into neat analytical techniques to understand different collision scenarios and we use those standard expressions to compute MOID analytically. We find the nature of this mathematical function is such that a relatively small GR precession can lead to drastic changes in MOID values depending on the initial value of argument of pericentre. Numerical integrations were done with the MERCURY package incorporating GR code to test the same effects. A numerical approach showed the same interesting relationship (as shown by analytical theory) between values of argument of pericentre and the peaks or dips in MOID values. There is an overall agreement between both analytical and numerical methods.We find that GR precession could play an important role in the calculations pertaining to MOID and close encounter scenarios in the case of certain small solar system bodies (depending on their initial orbital elements) when long term impact risk possibilities are considered. Previous works have looked into impact probabilities and collision scenarios on planets from different small body populations. This work aims to find certain sub-sets of small bodies where GR could play an

  20. A general equilibrium model of guest-worker migration: the source-country perspective.

    Science.gov (United States)

    Djajic, S; Milbourne, R

    1988-11-01

    "This paper examines the problem of guest-worker migration from an economy populated by identical, utility-maximizing individuals with finite working lives. The decision to migrate, the rate of saving while abroad, as well as the length of a migrant's stay in the foreign country, are all viewed as part of a solution to an intertemporal optimization problem. In addition to studying the microeconomic aspects of temporary migration, the paper analyses the determinants of the equilibrium flow of migrants, the corresponding domestic wage, and the level of welfare enjoyed by a typical worker. Effects of an emigration tax are also investigated."

  1. A new multi-dimensional general relativistic neutrino hydrodynamics code for core-collapse supernovae. IV. The neutrino signal

    Energy Technology Data Exchange (ETDEWEB)

    Müller, Bernhard [Monash Center for Astrophysics, School of Mathematical Sciences, Building 28, Monash University, Victoria 3800 (Australia); Janka, Hans-Thomas, E-mail: bernhard.mueller@monash.edu, E-mail: bjmuellr@mpa-garching.mpg.de, E-mail: thj@mpa-garching.mpg.de [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)

    2014-06-10

    Considering six general relativistic, two-dimensional (2D) supernova (SN) explosion models of progenitor stars between 8.1 and 27 M {sub ☉}, we systematically analyze the properties of the neutrino emission from core collapse and bounce to the post-explosion phase. The models were computed with the VERTEX-COCONUT code, using three-flavor, energy-dependent neutrino transport in the ray-by-ray-plus approximation. Our results confirm the close similarity of the mean energies, (E), of ν-bar {sub e} and heavy-lepton neutrinos and even their crossing during the accretion phase for stars with M ≳ 10 M {sub ☉} as observed in previous 1D and 2D simulations with state-of-the-art neutrino transport. We establish a roughly linear scaling of 〈E{sub ν-bar{sub e}}〉 with the proto-neutron star (PNS) mass, which holds in time as well as for different progenitors. Convection inside the PNS affects the neutrino emission on the 10%-20% level, and accretion continuing beyond the onset of the explosion prevents the abrupt drop of the neutrino luminosities seen in artificially exploded 1D models. We demonstrate that a wavelet-based time-frequency analysis of SN neutrino signals in IceCube will offer sensitive diagnostics for the SN core dynamics up to at least ∼10 kpc distance. Strong, narrow-band signal modulations indicate quasi-periodic shock sloshing motions due to the standing accretion shock instability (SASI), and the frequency evolution of such 'SASI neutrino chirps' reveals shock expansion or contraction. The onset of the explosion is accompanied by a shift of the modulation frequency below 40-50 Hz, and post-explosion, episodic accretion downflows will be signaled by activity intervals stretching over an extended frequency range in the wavelet spectrogram.

  2. An alternative order-parameter for non-equilibrium generalized spin models on honeycomb lattices

    Science.gov (United States)

    Sastre, Francisco; Henkel, Malte

    2016-04-01

    An alternative definition for the order-parameter is proposed, for a family of non-equilibrium spin models with up-down symmetry on honeycomb lattices, and which depends on two parameters. In contrast to the usual definition, our proposal takes into account that each site of the lattice can be associated with a local temperature which depends on the local environment of each site. Using the generalised voter motel as a test case, we analyse the phase diagram and the critical exponents in the stationary state and compare the results of the standard order-parameter with the ones following from our new proposal, on the honeycomb lattice. The stationary phase transition is in the Ising universality class. Finite-size corrections are also studied and the Wegner exponent is estimated as ω =1.06(9).

  3. A General Iterative Method of Fixed Points for Mixed Equilibrium Problems and Variational Inclusion Problems

    Directory of Open Access Journals (Sweden)

    Phayap Katchang

    2010-01-01

    Full Text Available The purpose of this paper is to investigate the problem of finding a common element of the set of solutions for mixed equilibrium problems, the set of solutions of the variational inclusions with set-valued maximal monotone mappings and inverse-strongly monotone mappings, and the set of fixed points of a family of finitely nonexpansive mappings in the setting of Hilbert spaces. We propose a new iterative scheme for finding the common element of the above three sets. Our results improve and extend the corresponding results of the works by Zhang et al. (2008, Peng et al. (2008, Peng and Yao (2009, as well as Plubtieng and Sriprad (2009 and some well-known results in the literature.

  4. 一般均衡理论的价值基础%The Value Foundation of General Equilibrium Theory

    Institute of Scientific and Technical Information of China (English)

    冯金华

    2012-01-01

    现代西方主流经济学中的一般均衡理论缺乏应有的价值基础。近年来试图建立马克思主义的一般均衡理论的努力也一直未能成功。然而,根据马克思的劳动价值论可以证明,在假定社会总产品的价格总量等于价值总量、平均利润总量等于剩余价值总量的条件下,必然有且仅有一个恰好等于相应价值向量的一般均衡价格向量。这意味着,一般均衡理论完全可以建立在劳动价值论的基础之上。本文首先根据马克思关于两大部类社会总产品构成的理论,建立包括技术关系在内的价值体系和相应的价格体系,其次说明在价格体系中存在有无穷多的一般均衡价格向量,最后从无穷多的一般均衡价格向量中确定一个"标准"的价格向量,并证明这个标准价格向量必然等于相应的价值向量。%There is no value foundation in modern general equilibrium theory of western mainstream economics.An effort trying to develop Marxist theory of general equilibrium has not succeeded too.However,It could be proved that,according to Marx's labor value theory,there exists one and only one general equilibrium price vector which equates exactly the relevant value vector,under the assumptions of that aggregate profits is equal to aggregate surplus value and aggregate prices is equal to aggregate value of the whole economy.It means that general equilibrium theory could be built on the basis of labor value theory.The paper firstly develops the value system and price system which include technique relations according to Marx's theory of social gross product of two departments,then shows that there are infinite general equilibrium price vectors in price system,and lastly determines a "standard" price vector from the infinite general equilibrium price vectors and proves that the standard price vector is necessarily equal to the corresponding value vector.

  5. Relativistic GLONASS and geodesy

    Science.gov (United States)

    Mazurova, E. M.; Kopeikin, S. M.; Karpik, A. P.

    2016-12-01

    GNSS technology is playing a major role in applications to civil, industrial and scientific areas. Nowadays, there are two fully functional GNSS: American GPS and Russian GLONASS. Their data processing algorithms have been historically based on the Newtonian theory of space and time with only a few relativistic effects taken into account as small corrections preventing the system from degradation on a fairly long time. Continuously growing accuracy of geodetic measurements and atomic clocks suggests reconsidering the overall approach to the GNSS theoretical model based on the Einstein theory of general relativity. This is essentially more challenging but fundamentally consistent theoretical approach to relativistic space geodesy. In this paper, we overview the basic principles of the relativistic GNSS model and explain the advantages of such a system for GLONASS and other positioning systems. Keywords: relativistic GLONASS, Einstein theory of general relativity.

  6. An Iterative Algorithm Combining Viscosity Method with Parallel Method for a Generalized Equilibrium Problem and Strict Pseudocontractions

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available We introduce a new approximation scheme combining the viscosity method with parallel method for finding a common element of the set of solutions of a generalized equilibrium problem and the set of fixed points of a family of finitely strict pseudocontractions. We obtain a strong convergence theorem for the sequences generated by these processes in Hilbert spaces. Based on this result, we also get some new and interesting results. The results in this paper extend and improve some well-known results in the literature.

  7. Assessing the macroeconomic impact of a healthcare problem: the application of computable general equilibrium analysis to antimicrobial resistance.

    Science.gov (United States)

    Smith, Richard D; Yago, Milton; Millar, Michael; Coast, Jo

    2005-11-01

    There is a positive relationship between the health of a nation and its economic prosperity. However, in evaluating health care, economists typically concentrate on the economic impact only to the health (care) sector, which may mis-specify the social costs and benefits of a disease or intervention. This paper demonstrates the value of using a macroeconomic approach to modelling a major health problem, using the context of antimicrobial resistance and the application of the computable general equilibrium technique. This approach is described in detail and its 'added value' demonstrated in the case of AMR.

  8. WEAK CONVERGENCE THEOREMS FOR GENERAL EQUILIBRIUM PROBLEMS AND VARIATIONAL INEQUALITY PROBLEMS AND FIXED POINT PROBLEMS IN BANACH SPACES

    Institute of Scientific and Technical Information of China (English)

    Gang CAI; Shangquan BU

    2013-01-01

    In this paper,we introduce two new iterative algorithms for finding a common element of the set of solutions of a general equilibrium problem and the set of solutions of the variational inequality for an inverse-strongly monotone operator and the set of common fixed points of two infinite families of relatively nonexpansive mappings or the set of common fixed points of an infinite family of relatively quasi-nonexpansive mappings in Banach spaces.Then we study the weak convergence of the two iterative sequences.Our results improve and extend the results announced by many others.

  9. Universal formulation of second-order generalized Møller-Plesset perturbation theory for a spin-dependent two-component relativistic many-electron Hamiltonian

    Science.gov (United States)

    Nakano, Masahiko; Seino, Junji; Nakai, Hiromi

    2017-05-01

    We have derived and implemented a universal formulation of the second-order generalized Møller-Plesset perturbation theory (GMP2) for spin-dependent (SD) two-component relativistic many-electron Hamiltonians, such as the infinite-order Douglas-Kroll-Hess Hamiltonian for many-electron systems, which is denoted as IODKH/IODKH. Numerical assessments for He- and Ne-like atoms and 16 diatomic molecules show that the MP2 correlation energies with IODKH/IODKH agree well with those calculated with the four-component Dirac-Coulomb (DC) Hamiltonian, indicating a systematic improvement on the inclusion of relativistic two-electron terms. The present MP2 scheme for IODKH/IODKH is demonstrated to be computationally more efficient than that for DC.

  10. Three-Dimensional General Relativistic Radiation Magnetohydrodynamical Simulation of Super-Eddington Accretion, using a new code HARMRAD with M1 Closure

    CERN Document Server

    McKinney, Jonathan C; Sadowski, Aleksander; Narayan, Ramesh

    2013-01-01

    Black hole (BH) accretion flows and jets are dynamic hot relativistic magnetized plasma flows whose radiative opacity can significantly affect flow structure and behavior. We describe a numerical scheme, tests, and an astrophysically relevant application using the M1 radiation closure within a new three-dimensional (3D) general relativistic (GR) radiation (R) magnetohydrodynamics (MHD) massively parallel code called HARMRAD. Our 3D GRRMHD simulation of super-Eddington accretion (about $20$ times Eddington) onto a rapidly rotating BH (dimensionless spin $j=0.9375$) shows sustained non-axisymmemtric disk turbulence, a persistent electromagnetic jet driven by the Blandford-Znajek effect, and a total radiative output consistently near the Eddington rate. The total accretion efficiency is of order $20\\%$, the large-scale electromagnetic jet efficiency is of order $10\\%$, and the total radiative efficiency that reaches large distances remains low at only order $1\\%$. However, the radiation jet and the electromagnet...

  11. Dirac equation with anisotropic oscillator, quantum E3‧ and Holt superintegrable potentials and relativistic generalized Yang-Coulomb monopole system

    Science.gov (United States)

    Mohammadi, Vahid; Chenaghlou, Alireza

    2017-09-01

    The two-dimensional Dirac equation with spin and pseudo-spin symmetries is investigated in the presence of the maximally superintegrable potentials. The integrals of motion and the quadratic algebras of the superintegrable quantum E3‧, anisotropic oscillator and the Holt potentials are studied. The corresponding Casimir operators and the structure functions of the mentioned superintegrable systems are found. Also, we obtain the relativistic energy spectra of the corresponding superintegrable systems. Finally, the relativistic energy eigenvalues of the generalized Yang-Coulomb monopole (YCM) superintegrable system (a SU(2) non-Abelian monopole) are calculated by the energy spectrum of the eight-dimensional oscillator which is dual to the former system by Hurwitz transformation.

  12. China’s Rare Earths Supply Forecast in 2025: A Dynamic Computable General Equilibrium Analysis

    Directory of Open Access Journals (Sweden)

    Jianping Ge

    2016-09-01

    Full Text Available The supply of rare earths in China has been the focus of significant attention in recent years. Due to changes in regulatory policies and the development of strategic emerging industries, it is critical to investigate the scenario of rare earth supplies in 2025. To address this question, this paper constructed a dynamic computable equilibrium (DCGE model to forecast the production, domestic supply, and export of China’s rare earths in 2025. Based on our analysis, production will increase by 10.8%–12.6% and achieve 116,335–118,260 tons of rare-earth oxide (REO in 2025, based on recent extraction control during 2011–2016. Moreover, domestic supply and export will be 75,081–76,800 tons REO and 38,797–39,400 tons REO, respectively. The technological improvements on substitution and recycling will significantly decrease the supply and mining activities of rare earths. From a policy perspective, we found that the elimination of export regulations, including export quotas and export taxes, does have a negative impact on China’s future domestic supply of rare earths. The policy conflicts between the increase in investment in strategic emerging industries, and the increase in resource and environmental taxes on rare earths will also affect China’s rare earths supply in the future.

  13. Fluctuation theorems and inequalities generalizing the second law of thermodynamics out of equilibrium.

    Science.gov (United States)

    Verley, Gatien; Lacoste, David

    2012-11-01

    We present a general framework for systems which are prepared in a nonstationary nonequilibrium state in the absence of any perturbation and which are then further driven through the application of a time-dependent perturbation. By assumption, the evolution of the system must be described by Markovian dynamics. We distinguish two different situations depending on the way the nonequilibrium state is prepared; either it is created by some driving or it results from a relaxation following some initial nonstationary conditions. Our approach is based on a recent generalization of the Hatano-Sasa relation for nonstationary probability distributions. We also investigate whether a form of the second law holds for separate parts of the entropy production and for any nonstationary reference process, a question motivated by the work of M. Esposito et al. [Phys. Rev. Lett. 104, 090601 (2010)]. We find that although the special structure of the theorems derived in this reference is not recovered in the general case, detailed fluctuation theorems still hold separately for parts of the entropy production. These detailed fluctuation theorems contain interesting generalizations of the second law of thermodynamics for nonequilibrium systems.

  14. The Optimal Price Ratio of Typical Energy Sources in Beijing Based on the Computable General Equilibrium Model

    Directory of Open Access Journals (Sweden)

    Yongxiu He

    2014-04-01

    Full Text Available In Beijing, China, the rational consumption of energy is affected by the insufficient linkage mechanism of the energy pricing system, the unreasonable price ratio and other issues. This paper combines the characteristics of Beijing’s energy market, putting forward the society-economy equilibrium indicator R maximization taking into consideration the mitigation cost to determine a reasonable price ratio range. Based on the computable general equilibrium (CGE model, and dividing four kinds of energy sources into three groups, the impact of price fluctuations of electricity and natural gas on the Gross Domestic Product (GDP, Consumer Price Index (CPI, energy consumption and CO2 and SO2 emissions can be simulated for various scenarios. On this basis, the integrated effects of electricity and natural gas price shocks on the Beijing economy and environment can be calculated. The results show that relative to the coal prices, the electricity and natural gas prices in Beijing are currently below reasonable levels; the solution to these unreasonable energy price ratios should begin by improving the energy pricing mechanism, through means such as the establishment of a sound dynamic adjustment mechanism between regulated prices and market prices. This provides a new idea for exploring the rationality of energy price ratios in imperfect competitive energy markets.

  15. Relativistic theories of materials

    CERN Document Server

    Bressan, Aldo

    1978-01-01

    The theory of relativity was created in 1905 to solve a problem concerning electromagnetic fields. That solution was reached by means of profound changes in fundamental concepts and ideas that considerably affected the whole of physics. Moreover, when Einstein took gravitation into account, he was forced to develop radical changes also in our space-time concepts (1916). Relativistic works on heat, thermodynamics, and elasticity appeared as early as 1911. However, general theories having a thermodynamic basis, including heat conduction and constitutive equations, did not appear in general relativity until about 1955 for fluids and appeared only after 1960 for elastic or more general finitely deformed materials. These theories dealt with materials with memory, and in this connection some relativistic versions of the principle of material indifference were considered. Even more recently, relativistic theories incorporating finite deformations for polarizable and magnetizable materials and those in which couple s...

  16. First preliminary tests of the general relativistic gravitomagnetic field of the Sun and new constraints on a Yukawa-like fifth force from planetary data

    OpenAIRE

    Iorio, Lorenzo

    2005-01-01

    The general relativistic Lense-Thirring precessions of the perihelia of the inner planets of the Solar System are about 10^-3 arcseconds per century. Recent improvements in planetary orbit determination may yield the first observational evidence of such a tiny effect. Indeed, corrections to the known perihelion rates of -0.0036 +/- 0.0050, -0.0002 +/- 0.0004 and 0.0001 +/- 0.0005 arcseconds per century were recently estimated by E.V. Pitjeva for Mercury, the Earth and Mars, respectively, on t...

  17. Two carrier temperatures non-equilibrium generalized Planck law for semiconductors

    Science.gov (United States)

    Gibelli, François; Lombez, Laurent; Guillemoles, Jean-François

    2016-10-01

    Planck's law of radiation describes the light emitted by a blackbody. This law has been generalized in the past for the case of a non-blackbody material having a quasi Fermi-level splitting: the lattice of the material and the carriers are then considered in an isothermal regime. Hot carrier spectroscopy deals with carriers out of the isothermal regime, as their respective temperatures (THe ≠ THh) are considered to be different than that of the lattice (TL). Here we show that Fermi-Dirac distribution temperature for each type of carrier still determine an effective radiation temperature: an explicit relationship is given involving the effective masses. Moreover, we show how to determine, in principle with an additional approximation, the carrier temperatures (THe, THh) and the corresponding absolute electrochemical potentials from photoluminescence measurements.

  18. Universal thermodynamics in different gravity theories: Conditions for generalized second law of thermodynamics and thermodynamical equilibrium on the horizons

    CERN Document Server

    Mitra, Saugata; Chakraborty, Subenoy

    2016-01-01

    The present work deals with a detailed study of universal thermodynamics in different modified gravity theories. The validity of the generalized second law of thermodynamics (GSLT) and thermodynamical equilibrium (TE) of the Universe bounded by a horizon (apparent/event) in f(R)-gravity, Einstein-Gauss-Bonnet gravity, RS-II brane scenario and DGP brane model has been investigated. In the perspective of recent observational evidences, the matter in the Universe is chosen as interacting holographic dark energy model. The entropy on the horizons are evaluated from the validity of the unified first law and as a result there is a correction (in integral form) to the usual Bekenstein entropy. The other thermodynamical parameter namely temperature on the horizon is chosen as the recently introduced corrected Hawking temperature. The above thermodynamical analysis is done for homogeneous and isotropic flat FLRW model of the Universe. The restrictions for the validity of GSLT and the TE are presented in tabular form f...

  19. A System of Generalized Mixed Equilibrium Problems, Maximal Monotone Operators, and Fixed Point Problems with Application to Optimization Problems

    Directory of Open Access Journals (Sweden)

    Pongsakorn Sunthrayuth

    2012-01-01

    Full Text Available We introduce a new iterative algorithm for finding a common element of the set of solutions of a system of generalized mixed equilibrium problems, zero set of the sum of a maximal monotone operators and inverse-strongly monotone mappings, and the set of common fixed points of an infinite family of nonexpansive mappings with infinite real number. Furthermore, we prove under some mild conditions that the proposed iterative algorithm converges strongly to a common element of the above four sets, which is a solution of the optimization problem related to a strongly positive bounded linear operator. The results presented in the paper improve and extend the recent ones announced by many others.

  20. An inexact generalized PRSM with LQP regularization for structured variational inequalities and its applications to traffic equilibrium problems

    Directory of Open Access Journals (Sweden)

    Min Sun

    2016-06-01

    Full Text Available Abstract As one of the operator splitting methods, the Peaceman-Rachford splitting method (PRSM has attracted considerable attention recently. This paper proposes a generalized PRSM for structured variational inequalities with positive orthants. In fact, we apply the well-developed LQP regularization to regularize the subproblems of the recently proposed strictly contractive PRSM, thus the resulting subproblems reduce to two nonlinear equation systems, which are much easier to solve than the subproblems of PRSM. Furthermore, these two nonlinear equations are allowed to be solved inexactly. For the new method, we prove its global convergence and establish its worst-case convergence rate in the ergodic sense. Numerical experiments show that the proposed method is quite efficient for the traffic equilibrium problems with link capacity bound.

  1. Relativistic magnetohydrodynamics in one dimension.

    Science.gov (United States)

    Lyutikov, Maxim; Hadden, Samuel

    2012-02-01

    We derive a number of solutions for one-dimensional dynamics of relativistic magnetized plasma that can be used as benchmark estimates in relativistic hydrodynamic and magnetohydrodynamic numerical codes. First, we analyze the properties of simple waves of fast modes propagating orthogonally to the magnetic field in relativistically hot plasma. The magnetic and kinetic pressures obey different equations of state, so that the system behaves as a mixture of gases with different polytropic indices. We find the self-similar solutions for the expansion of hot strongly magnetized plasma into vacuum. Second, we derive linear hodograph and Darboux equations for the relativistic Khalatnikov potential, which describe arbitrary one-dimensional isentropic relativistic motion of cold magnetized plasma and find their general and particular solutions. The obtained hodograph and Darboux equations are very powerful: A system of highly nonlinear, relativistic, time-dependent equations describing arbitrary (not necessarily self-similar) dynamics of highly magnetized plasma reduces to a single linear differential equation.

  2. Magnetizability of the relativistic hydrogenlike atom in an arbitrary discrete energy eigenstate: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function

    CERN Document Server

    Stefańska, Patrycja

    2016-01-01

    The Sturmian expansion of the generalized Dirac--Coulomb Green function [R.\\/~Szmytkowski, J.\\ Phys.\\ B \\textbf{30}, 825 (1997); \\textbf{30}, 2747(E) (1997)] is exploited to derive a closed-form expression for the magnetizability of the relativistic one-electron atom in an arbitrary discrete state, with a point-like, spinless and motionless nucleus of charge $Ze$. The result has the form of a double finite sum involving the generalized hypergeometric functions ${}_3F_2$ of the unit argument. Our general expression agrees with formulas obtained analytically earlier by other authors for some particular states of the atom. We present also numerical values of the magnetizability for some excited states of selected hydrogenlike ions with $1 \\leqslant Z \\leqslant 137$ and compare them with data available in the literature.

  3. A Sufficient Condition for General Equilibrium in Indivisible Markets%不可分市场中一般均衡的一个充分条件

    Institute of Scientific and Technical Information of China (English)

    李春林; 李秀军; 姚冉婷

    2006-01-01

    This paper generalizes the general equilibrium theorem to the case of indivisible markets where preferences is strictly convex, continuous and strongly monotonous.%给出了不可分市场中一般均衡存在的一个充分条件:消费者偏好函数是强凸、连续和严格单调的.

  4. Relativistic cosmological hydrodynamics

    CERN Document Server

    Hwang, J

    1997-01-01

    We investigate the relativistic cosmological hydrodynamic perturbations. We present the general large scale solutions of the perturbation variables valid for the general sign of three space curvature, the cosmological constant, and generally evolving background equation of state. The large scale evolution is characterized by a conserved gauge invariant quantity which is the same as a perturbed potential (or three-space curvature) in the comoving gauge.

  5. Magnetic-field-induced electric quadrupole moments for relativistic hydrogenlike atoms: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function

    CERN Document Server

    Stefańska, Patrycja

    2016-01-01

    We consider a Dirac one-electron atom placed in a weak, static, uniform magnetic field. We show that, to the first order in the strength B of the external field, the only electric multipole moments, which are induced by the perturbation in the atom, are those of an even order. Using the Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B 30, 825 (1997); 30, 2747(E) (1997)], we derive a closed-form expression for the electric quadrupole moment induced in the atom in an arbitrary discrete energy eigenstate. The result, which has the form of a double finite sum involving the generalized hypergeometric functions 3F2 of the unit argument, agrees with the earlier relativistic formula for that quantity, obtained by us for the ground state of the atom.

  6. Magnetic-field-induced electric quadrupole moments for relativistic hydrogenlike atoms: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function

    Science.gov (United States)

    Stefańska, Patrycja

    2016-02-01

    We consider a Dirac one-electron atom placed in a weak, static, uniform magnetic field. We show that, to the first order in the strength B of the external field, the only electric multipole moments, which are induced by the perturbation in the atom, are those of an even order. Using the Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B 30, 825 (1997), 10.1088/0953-4075/30/4/007; J. Phys. B 30, 2747 (1997), 10.1088/0953-4075/30/11/023], We derive a closed-form expression for the electric quadrupole moment induced in the atom in an arbitrary discrete energy eigenstate. The result, which has the form of a double finite sum involving the generalized hypergeometric functions 3F2 of the unit argument, agrees with the earlier relativistic formula for that quantity, obtained by us for the ground state of the atom.

  7. Relativistic cosmology; Cosmologia Relativista

    Energy Technology Data Exchange (ETDEWEB)

    Bastero-Gil, M.

    2015-07-01

    Relativistic cosmology is nothing but the study of the evolution of our universe expanding from the General Theory of Relativity, which describes the gravitational interaction at any scale and given its character far-reaching is the force that dominate the evolution of the universe. (Author)

  8. Relativistic Disc lines

    CERN Document Server

    Fabian, A C; Parker, M L

    2014-01-01

    Broad emission lines, particularly broad iron-K lines, are now commonly seen in the X-ray spectra of luminous AGN and Galactic black hole binaries. Sensitive NuSTAR spectra over the energy range of 3-78 keV and high frequency reverberation spectra now confirm that these are relativistic disc lines produced by coronal irradiation of the innermost accretion flow around rapidly spinning black holes. General relativistic effects are essential in explaining the observations. Recent results are briefly reviewed here.

  9. A General Equilibrium Theory in Discrete Spaces%离散空间中的一般均衡理论

    Institute of Scientific and Technical Information of China (English)

    李春林; 屈驳韵

    2006-01-01

    This paper generalizes the general equilibrium theorem to the case of indivisible markets where preferences is strictly convex,continuous and strongly monotone.The authors thus give a sufficient condition on the existence of discrete equilibrium.%在消费者偏好函数是强凸、连续和严格单调的条件下,给出了不可分市场的一般均衡存在定理,因而也给出了离散空间中一般均衡存在的一个充分条件.

  10. Existence and Strong Convergence Theorems for Generalized Mixed Equilibrium Problems of a Finite Family of Asymptotically Nonexpansive Mappings in Banach Spaces

    Directory of Open Access Journals (Sweden)

    Rabian Wangkeeree

    2012-01-01

    Full Text Available We first prove the existence of solutions for a generalized mixed equilibrium problem under the new conditions imposed on the given bifunction and introduce the algorithm for solving a common element in the solution set of a generalized mixed equilibrium problem and the common fixed point set of finite family of asymptotically nonexpansive mappings. Next, the strong convergence theorems are obtained, under some appropriate conditions, in uniformly convex and smooth Banach spaces. The main results extend various results existing in the current literature.

  11. First evidence of the general relativistic gravitomagnetic field of the Sun and new constraints on a Yukawa-like fifth force

    CERN Document Server

    Iorio, L

    2005-01-01

    The post-Newtonian general relativistic gravitomagnetic Lense-Thirring precessions of the perihelia of the inner planets of the Solar System amount to 10^-3 arcseconds per century. Up to now they were always retained too small to be detected. Recent improvements in the planetary ephemerides determination yield the first observational evidence of such a tiny effect. Indeed, extra-corrections to the known perihelion advances of -0.0036\\pm 0.0050, -0.0002\\pm 0.0004 and 0.0001\\pm 0.0005 arcseconds per century were recently determined by E.V. Pitjeva for Mercury, the Earth and Mars, respectively. They were based on the EPM2004 ephemerides and a set of more than 317 000 observations of various kinds. The predicted relativistic Thirring-Lense precessions for these planets are -0.0020, -0.0001 and -3\\times 10^-5 arcseconds per century, respectively and are compatible with the measured perihelia corrections, although the experimental errors are still large. The data from the forthcoming BepiColombo mission to Mercury ...

  12. A new multi-dimensional general relativistic neutrino hydrodynamics code for core-collapse supernovae. I. Method and code tests in spherical symmetry

    CERN Document Server

    Mueller, B; Dimmelmeier, H

    2010-01-01

    We present a new general relativistic (GR) code for hydrodynamic supernova simulations with neutrino transport in spherical and azimuthal symmetry (1D/2D). The code is a combination of the CoCoNuT hydro module, which is a Riemann-solver based, high-resolution shock-capturing method, and the three-flavor, energy-dependent neutrino transport scheme VERTEX. VERTEX integrates the neutrino moment equations with a variable Eddington factor closure computed from a model Boltzmann equation and uses the ray-by-ray plus approximation in 2D, assuming the neutrino distribution to be axially symmetric around the radial direction, and thus the neutrino flux to be radial. Our spacetime treatment employs the ADM 3+1 formalism with the conformal flatness condition for the spatial three-metric. This approach is exact in 1D and has been shown to yield very accurate results also for rotational stellar collapse. We introduce new formulations of the energy equation to improve total energy conservation in relativistic and Newtonian...

  13. Chemical Principles Revisited: Chemical Equilibrium.

    Science.gov (United States)

    Mickey, Charles D.

    1980-01-01

    Describes: (1) Law of Mass Action; (2) equilibrium constant and ideal behavior; (3) general form of the equilibrium constant; (4) forward and reverse reactions; (5) factors influencing equilibrium; (6) Le Chatelier's principle; (7) effects of temperature, changing concentration, and pressure on equilibrium; and (8) catalysts and equilibrium. (JN)

  14. Relativistic hydrodynamics

    CERN Document Server

    Luciano, Rezzolla

    2013-01-01

    Relativistic hydrodynamics is a very successful theoretical framework to describe the dynamics of matter from scales as small as those of colliding elementary particles, up to the largest scales in the universe. This book provides an up-to-date, lively, and approachable introduction to the mathematical formalism, numerical techniques, and applications of relativistic hydrodynamics. The topic is typically covered either by very formal or by very phenomenological books, but is instead presented here in a form that will be appreciated both by students and researchers in the field. The topics covered in the book are the results of work carried out over the last 40 years, which can be found in rather technical research articles with dissimilar notations and styles. The book is not just a collection of scattered information, but a well-organized description of relativistic hydrodynamics, from the basic principles of statistical kinetic theory, down to the technical aspects of numerical methods devised for the solut...

  15. Housing demand or money supply? A new Keynesian dynamic stochastic general equilibrium model on China's housing market fluctuations

    Science.gov (United States)

    Wen, Xing-Chun; He, Ling-Yun

    2015-08-01

    There is a bitter controversy over what drives the housing price in China in the existing literature. In this paper, we investigate the underlying driving force behind housing price fluctuations in China, especially focusing on the role of housing demand shock with that of money supply shock in explaining housing price movements, by a new Keynesian dynamic stochastic general equilibrium model. Empirical results suggest that it is housing demand, instead of money supply, that mainly drives China's housing price movements. Relevant policy implication is further discussed, namely, whether to consider the housing price fluctuations in the conduct of monetary policy. By means of the policy simulations, we find that a real house price-augmented money supply rule is a better monetary policy for China's economy stabilization. 1. Investment refers to fixed capital investment. 2. Housing price refers to national average housing price. Quarterly data on housing price during the period of our work are not directly available. However, monthly data of the value of sales on housing and sale volume on housing can be directly obtained from National Bureau of Statistics of China. We add up the monthly data and calculate one quarter's housing price by dividing the value of housing sales by its sale volume in one quarter. 3. M2 means the broad money supply in China.

  16. The impact of a stimulus to energy efficiency on the economy and the environment: A regional computable general equilibrium analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hanley, Nick D. [Department of Economics, University of Stirling, Stirling FK9 4LA (United Kingdom); McGregor, Peter G.; Swales, J. Kim [Fraser of Allander Institute, CPPR and Department of Economics, University of Strathclyde, Sir William Duncan Building, 130 Rottenrow, Glasgow G4 0GE (United Kingdom); Turner, Karen [Fraser of Allander Institute and Department of Economics, University of Strathclyde, Sir William Duncan Building, 130 Rottenrow, Glasgow G4 0GE (United Kingdom)

    2006-02-01

    Sustainable development is a key objective of UK national and regional policies. Improvements in resource productivity have been suggested as both a measure of progress towards sustainable development and as a means of achieving sustainability. Making 'more with less' intuitively seems to be good for the environment, and this is the presumption of current UK policy. However, in a system-wide context, improvements in energy efficiency lower the cost of energy in efficiency units and may even stimulate the consumption and production of energy measured in physical units, and increase pollution. Simulations of a computable general equilibrium model of Scotland suggest that an across the board stimulus to energy efficiency there would actually stimulate energy production and consumption and lead to a deterioration in environmental indicators. The implication is that policies directed at stimulating energy efficiency are not, in themselves, sufficient to secure environmental improvements: this may require the use of complementary energy policies designed to moderate incentives to increased energy consumption. (author)

  17. Reducing CO{sub 2}- emissions under fiscal retrenchment. A multi-cohort computable general equilibrium (CGE) model for Austria

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, K.; Steininger, K.W. [Department of Economics, University of Graz, Graz (Austria)

    1999-04-01

    The stabilization of budget deficit and budget debt ratios by fiscal retrenchment in order to fulfill the Maastricht criteria for the European Monetary Union (EMU) is of central focus in most European Union (EU) countries. At the same time the national policy dimension of acute environmental problems such as global warming has receded in the public eye. The environmental dimension nonetheless remains urgent, and a re-evaluation of the prospects of CO{sub 2}-policy is needed against the background of fiscal retrenchment required by supranational obligations. We shall do this for the small, open, Austrian economy by constructing a dynamic multi-cohort computable general equilibrium (CGE) model enabling us to assess quantitatively the lifetime welfare impacts on the cohorts affected by three different options for using CO{sub 2}-permit revenues. The distribution of welfare costs of (Toronto-) CO{sub 2}-policy across cohorts significantly differs with use. This is explained by income, inheritance and price effects. 42 refs.

  18. Uncertain long-run emissions targets, CO{sub 2} price and global energy transition. A general equilibrium approach

    Energy Technology Data Exchange (ETDEWEB)

    Durand-Lasserve, Olivier; Smeers, Yves [Universite Catholique de Louvain (UCL), CORE, Voie du Roman Pays 34, B-1348 Louvain-la-Neuve (Belgium); Pierru, Axel [IFP, Economics Department, 232 Avenue Napoleon Bonaparte, 92852 Rueil-Malmaison (France)

    2010-09-15

    The persistent uncertainty about mid-century CO{sub 2} emissions targets is likely to affect not only the technological choices that energy-producing firms will make in the future but also their current investment decisions. We illustrate this effect on CO{sub 2} price and global energy transition within a MERGE-type general-equilibrium model framework, by considering simple stochastic CO{sub 2} policy scenarios. In these scenarios, economic agents know that credible long-run CO{sub 2} emissions targets will be set in 2020, with two possible outcomes: either a hard cap or a soft cap. Each scenario is characterized by the relative probabilities of both possible caps. We derive consistent stochastic trajectories - with two branches after 2020 - for prices and quantities of energy commodities and CO{sub 2} emissions permits. The impact of uncertain long-run CO{sub 2} emissions targets on prices and technological trajectories is discussed. In addition, a simple marginal approach allows us to analyze the Hotelling rule with risk premia observed for certain scenarios. (author)

  19. Uncertain long-run emissions targets, CO{sub 2} price and global energy transition: A general equilibrium approach

    Energy Technology Data Exchange (ETDEWEB)

    Durand-Lasserve, Olivier, E-mail: olivier.durand@uclouvain.b [Universite Catholique de Louvain (UCL), CORE, Voie du Roman Pays 34, B-1348 Louvain-la-Neuve (Belgium); Pierru, Axel, E-mail: axel.pierru@ifp.f [IFP, Economics Department, 232 Avenue Napoleon Bonaparte, 92852 Rueil-Malmaison (France); Smeers, Yves, E-mail: yves.smeers@uclouvain.ac.b [Universite Catholique de Louvain (UCL), CORE, Voie du Roman Pays 34, B-1348 Louvain-la-Neuve (Belgium)

    2010-09-15

    The persistent uncertainty about mid-century CO{sub 2} emissions targets is likely to affect not only the technological choices that energy-producing firms will make in the future but also their current investment decisions. We illustrate this effect on CO{sub 2} price and global energy transition within a MERGE-type general-equilibrium model framework, by considering simple stochastic CO{sub 2} policy scenarios. In these scenarios, economic agents know that credible long-run CO{sub 2} emissions targets will be set in 2020, with two possible outcomes: either a 'hard cap' or a 'soft cap'. Each scenario is characterized by the relative probabilities of both possible caps. We derive consistent stochastic trajectories-with two branches after 2020-for prices and quantities of energy commodities and CO{sub 2} emissions permits. The impact of uncertain long-run CO{sub 2} emissions targets on prices and technological trajectories is discussed. In addition, a simple marginal approach allows us to analyze the Hotelling rule with risk premia observed for certain scenarios.

  20. Economic impacts of bio-refinery and resource cascading systems: an applied general equilibrium analysis for Poland.

    Science.gov (United States)

    Ignaciuk, Adriana M; Sanders, Johan

    2007-12-01

    Due to more stringent energy and climate policies, it is expected that many traditional chemicals will be replaced by their biomass-based substitutes, bio-chemicals. These innovations, however, can influence land allocation since the demand for land dedicated to specific crops might increase. Moreover, it can have an influence on traditional agricultural production. In this paper, we use an applied general equilibrium framework, in which we include two different bio-refinery processes and incorporate so-called cascading mechanisms. The bio-refinery processes use grass, as one of the major inputs, to produce bio-nylon and propane-diol (1,3PDO) to substitute currently produced fossil fuel-based nylon and ethane-diol. We examine the impact of specific climate policies on the bioelectricity share in total electricity production, land allocation, and production quantities and prices of selected commodities. The novel technologies become competitive, with an increased stringency of climate policies. This switch, however, does not induce a higher share of bioelectricity. The cascade does stimulate the production of bioelectricity, but it induces more of a shift in inputs in the bioelectricity sector (from biomass to the cascaded bio-nylon and 1, 3PDO) than an increase in production level of bioelectricity. We conclude that dedicated biomass crops will remain the main option for bioelectricity production: the contribution of the biomass systems remains limited. Moreover, the bioelectricity sector looses a competition for land for biomass production with bio-refineries.

  1. Air pollution-induced health impacts on the national economy of China: demonstration of a computable general equilibrium approach.

    Science.gov (United States)

    Wan, Yue; Yang, Hongwei; Masui, Toshihiko

    2005-01-01

    At the present time, ambient air pollution is a serious public health problem in China. Based on the concentration-response relationship provided by international and domestic epidemiologic studies, the authors estimated the mortality and morbidity induced by the ambient air pollution of 2000. To address the mechanism of the health impact on the national economy, the authors applied a computable general equilibrium (CGE) model, named AIM/Material China, containing 39 production sectors and 32 commodities. AIM/Material analyzes changes of the gross domestic product (GDP), final demand, and production activity originating from health damages. If ambient air quality met Grade II of China's air quality standard in 2000, then the avoidable GDP loss would be 0.38%o of the national total, of which 95% was led by labor loss. Comparatively, medical expenditure had less impact on national economy, which is explained from the aspect of the final demand by commodities and the production activities by sectors. The authors conclude that the CGE model is a suitable tool for assessing health impacts from a point of view of national economy through the discussion about its applicability.

  2. Economic Impacts of Potential Foot and Mouth Disease Agro-terrorism in the United States: A Computable General Equilibrium Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Oladosu, Gbadebo A [ORNL; Rose, Adam [University of Southern California, Los Angeles; Bumsoo, Lee [University of Illinois

    2013-01-01

    The foot and mouth disease (FMD) virus has high agro-terrorism potential because it is contagious, can be easily transmitted via inanimate objects and can be spread by wind. An outbreak of FMD in developed countries results in massive slaughtering of animals (for disease control) and disruptions in meat supply chains and trade, with potentially large economic losses. Although the United States has been FMD-free since 1929, the potential of FMD as a deliberate terrorist weapon calls for estimates of the physical and economic damage that could result from an outbreak. This paper estimates the economic impacts of three alternative scenarios of potential FMD attacks using a computable general equilibrium (CGE) model of the US economy. The three scenarios range from a small outbreak successfully contained within a state to a large multi-state attack resulting in slaughtering of 30 percent of the national livestock. Overall, the value of total output losses in our simulations range between $37 billion (0.15% of 2006 baseline economic output) and $228 billion (0.92%). Major impacts stem from the supply constraint on livestock due to massive animal slaughtering. As expected, the economic losses are heavily concentrated in agriculture and food manufacturing sectors, with losses ranging from $23 billion to $61 billion in the two industries.

  3. Relativistic formulation and reference frame

    OpenAIRE

    Klioner, Sergei A.

    2004-01-01

    After a short review of experimental foundations of metric theories of gravity, the choice of general relativity as a theory to be used for the routine modeling of Gaia observations is justified. General principles of relativistic modeling of astronomical observations are then sketched and compared to the corresponding Newtonian principles. The fundamental reference system -- Barycentric Celestial Reference System, which has been chosen to be the relativistic reference system underlying the f...

  4. Fractional Dynamics of Relativistic Particle

    CERN Document Server

    Tarasov, Vasily E

    2011-01-01

    Fractional dynamics of relativistic particle is discussed. Derivatives of fractional orders with respect to proper time describe long-term memory effects that correspond to intrinsic dissipative processes. Relativistic particle subjected to a non-potential four-force is considered as a nonholonomic system. The nonholonomic constraint in four-dimensional space-time represents the relativistic invariance by the equation for four-velocity u_{\\mu} u^{\\mu}+c^2=0, where c is a speed of light in vacuum. In the general case, the fractional dynamics of relativistic particle is described as non-Hamiltonian and dissipative. Conditions for fractional relativistic particle to be a Hamiltonian system are considered.

  5. Anderson-Witting transport coefficients for flows in general relativity

    CERN Document Server

    Ambrus, Victor E

    2016-01-01

    The transport coefficients induced by the Anderson-Witting approximation of the collision term in the relativistic Boltzmann equation are derived for close to equilibrium flows in general relativity. Using the tetrad formalism, it is shown that the expression for these coefficients is the same as that obtained on flat space-time, in agreement with the generalized equivalence principle.

  6. Generalized thermodynamic relations for a system experiencing heat and mass diffusion in the far-from-equilibrium realm based on steepest entropy ascent.

    Science.gov (United States)

    Li, Guanchen; von Spakovsky, Michael R

    2016-09-01

    This paper presents a nonequilibrium thermodynamic model for the relaxation of a local, isolated system in nonequilibrium using the principle of steepest entropy ascent (SEA), which can be expressed as a variational principle in thermodynamic state space. The model is able to arrive at the Onsager relations for such a system. Since no assumption of local equilibrium is made, the conjugate fluxes and forces are intrinsic to the subspaces of the system's state space and are defined using the concepts of hypoequilibrium state and nonequilibrium intensive properties, which describe the nonmutual equilibrium status between subspaces of the thermodynamic state space. The Onsager relations are shown to be a thermodynamic kinematic feature of the system independent of the specific details of the micromechanical dynamics. Two kinds of relaxation processes are studied with different constraints (i.e., conservation laws) corresponding to heat and mass diffusion. Linear behavior in the near-equilibrium region as well as nonlinear behavior in the far-from-equilibrium region are discussed. Thermodynamic relations in the equilibrium and near-equilibrium realm, including the Gibbs relation, the Clausius inequality, and the Onsager relations, are generalized to the far-from-equilibrium realm. The variational principle in the space spanned by the intrinsic conjugate fluxes and forces is expressed via the quadratic dissipation potential. As an application, the model is applied to the heat and mass diffusion of a system represented by a single-particle ensemble, which can also be applied to a simple system of many particles. Phenomenological transport coefficients are also derived in the near-equilibrium realm.

  7. Binary neutron-star mergers with Whisky and SACRA: First quantitative comparison of results from independent general-relativistic hydrodynamics codes

    Science.gov (United States)

    Baiotti, Luca; Shibata, Masaru; Yamamoto, Tetsuro

    2010-09-01

    We present the first quantitative comparison of two independent general-relativistic hydrodynamics codes, the whisky code and the sacra code. We compare the output of simulations starting from the same initial data and carried out with the configuration (numerical methods, grid setup, resolution, gauges) which for each code has been found to give consistent and sufficiently accurate results, in particular, in terms of cleanness of gravitational waveforms. We focus on the quantities that should be conserved during the evolution (rest mass, total mass energy, and total angular momentum) and on the gravitational-wave amplitude and frequency. We find that the results produced by the two codes agree at a reasonable level, with variations in the different quantities but always at better than about 10%.

  8. Binary neutron-star mergers with Whisky and SACRA: First quantitative comparison of results from independent general-relativistic hydrodynamics codes

    CERN Document Server

    Baiotti, Luca; Yamamoto, Tetsuro

    2010-01-01

    We present the first quantitative comparison of two independent general-relativistic hydrodynamics codes, the Whisky code and the SACRA code. We compare the output of simulations starting from the same initial data and carried out with the configuration (numerical methods, grid setup, resolution, gauges) which for each code has been found to give consistent and sufficiently accurate results, in particular in terms of cleanness of gravitational waveforms. We focus on the quantities that should be conserved during the evolution (rest mass, total mass energy, and total angular momentum) and on the gravitational-wave amplitude and frequency. We find that the results produced by the two codes agree at a reasonable level, with variations in the different quantities but always at better than about 10%.

  9. Assessing the economic impact of North China’s water scarcity mitigation strategy : a multi - region, water - extended computable general equilibrium analysis

    NARCIS (Netherlands)

    Qin, C.; Su, Z.; Bressers, J.T.A.; Jia, Y.; Wang, H.

    2013-01-01

    This paper describes a multi-region computable general equilibrium model for analyzing the effectiveness of measures and policies for mitigating North China’s water scarcity with respect to three different groups of scenarios. The findings suggest that a reduction in groundwater use would negatively

  10. Macroeconomic effects of a currency devaluation in Egypt - An analysis with a computable general equilibrium model with financial markets and forward-looking expectations

    NARCIS (Netherlands)

    Thissen, M.J.P.M.; Lensink, B.W.

    2001-01-01

    This paper presents a general equilibrium model for Egypt, which allows for different forms of expectations formation and takes financial markets into account. Moreover, it uses a new calibration method. The model is used to examine the macroeconomic effects of a currency devaluation. The results sh

  11. A Comparative Analysis of Some Policy Options to Reduce Rationing in the UK’s NHS: Lessons from a General Equilibrium Model Incorporating Positive Health Effects

    NARCIS (Netherlands)

    Rutten, M.M.; Reed, G.

    2009-01-01

    This paper seeks to determine the macro-economic impacts of changes in health care provision. The resource allocation issues have been explored in theory, by applying the Rybczynski theorem, and empirically, using a computable general equilibrium (CGE) model for the UK with a detailed health compone

  12. A quantum-information-theoretic complement to a general-relativistic implementation of a beyond-Turing computer

    CERN Document Server

    Wuthrich, Christian

    2014-01-01

    There exists a growing literature on the so-called physical Church-Turing thesis in a relativistic spacetime setting. The physical Church-Turing thesis is the conjecture that no computing device that is physically realizable (even in principle) can exceed the computational barriers of a Turing machine. By suggesting a concrete implementation of a beyond-Turing computer in a spacetime setting, Istv\\'an N\\'emeti and Gyula D\\'avid (2006) have shown how an appreciation of the physical Church-Turing thesis necessitates the confluence of mathematical, computational, physical, and indeed cosmological ideas. In this essay, I will honour Istv\\'an's seventieth birthday, as well as his longstanding interest in, and his seminal contributions to, this field going back to as early as 1987 by modestly proposing how the concrete implementation in N\\'emeti and D\\'avid (2006) might be complemented by a quantum-information-theoretic communication protocol between the computing device and the logician who sets the beyond-Turing ...

  13. Relativistic Kinematics

    CERN Document Server

    Sahoo, Raghunath

    2016-01-01

    This lecture note covers Relativistic Kinematics, which is very useful for the beginners in the field of high-energy physics. A very practical approach has been taken, which answers "why and how" of the kinematics useful for students working in the related areas.

  14. ASSESSING THE ECONOMIC IMPACTS OF INCORPORATING ROMANIAN'S AGRICULTURAL AND FOOD SECTORS INTO EU'S CUSTOMS UNION: AN APPLIED GENERAL EQUILIBRIUM APPROACH

    Directory of Open Access Journals (Sweden)

    Silviu S. Scrieciu

    2004-10-01

    Full Text Available Joining the European Union club implies, among many other policy changes, full integration of Romania’s economy into EU’s customs union. This is expected to have significant implications for domestic farmers and food processors. The paper constructs a single-country Applied General Equilibrium (AGE model to investigate the impact of tariff border adjustments on changes in relative prices, production and trade patterns associated with fifteen local agro-food activities. Moreover, the modelling work identifies those agro-food sectors that have the potential to benefit the most from EU enlargement in terms of output effects given that Romanian producers are capable of fully responding to the incentives provided with integration. These mainly include (bovine live animals and meat products, sugar, and cereal grains. Agro-food trade with EU intensifies in particular for those commodities for which trade restrictions are still substantial prior to accession. However, the magnitude of changes is relatively small due to the weak integration of domestic agro-food sectors into international trade structures. The AGE model also predicts static welfare gains of 0.65 percent of GDP equivalent variation. These seem to be more associated with better access to EU markets and increased export prices, and less with the preferential unilateral elimination of tariffs or their adjustment to EU’s external levels. The model assumptions are highly theoretical and the model structure does not reflect with fidelity the workings of an economy in transition. Nonetheless, it does represent a solid base upon which further improvements could be added and structural transitional issues could be attached to more accurately predict potential outcomes.

  15. Estimating the economic impact of pandemic influenza: An application of the computable general equilibrium model to the U.K.

    Science.gov (United States)

    Smith, Richard D; Keogh-Brown, Marcus R; Barnett, Tony

    2011-07-01

    There is concern regarding the impact that a global infectious disease pandemic might have, especially the economic impact in the current financial climate. However, preparedness planning concentrates more upon population health and maintaining a functioning health sector than on the wider economic impact. We developed a single country Computable General Equilibrium model to estimate the economic impact of pandemic influenza (PI) and associated policies. While the context for this development was the United Kingdom, there are lessons to be drawn for application of this methodology, as well as indicative results, to other contexts. Disease scenarios were constructed from an epidemiological model which estimated case fatality rates (mild, moderate and severe) as 0.06%, 0.18% and 0.35%. A clinical attack rate of 35% was also used to produce influenza scenarios, together with preparedness policies, including antivirals and school closure, and the possible prophylactic absence of workers. U.K. cost estimates (in Sterling) are presented, together with relative percentage impacts applicable to similar large economies. Percentage/cost estimates suggest PI would reduce GDP by 0.3% (£ 3.5 bn), 0.4% (£ 5 bn) and 0.6% (£ 7.4 bn) respectively for the three disease scenarios. However, the impact of PI itself is smaller than disease mitigation policies: combining school closure with prophylactic absenteeism yields percentage/cost effects of 1.1% (£ 14.7 bn), 1.3% (£ 16.3 bn) and 1.4% (£ 18.5 bn) respectively for the three scenarios. Sensitivity analysis shows little variability with changes in disease parameters but notable changes with variations in school closure and prophylactic absenteeism. The most severe sensitivity scenario results in a 2.9% (£ 37.4 bn), 3.2% (£ 41.4 bn) and 3.7% (£ 47.5 bn) loss to GDP respectively for the three scenarios.

  16. The economy-wide impact of pandemic influenza on the UK: a computable general equilibrium modelling experiment.

    Science.gov (United States)

    Smith, Richard D; Keogh-Brown, Marcus R; Barnett, Tony; Tait, Joyce

    2009-11-19

    To estimate the potential economic impact of pandemic influenza, associated behavioural responses, school closures, and vaccination on the United Kingdom. A computable general equilibrium model of the UK economy was specified for various combinations of mortality and morbidity from pandemic influenza, vaccine efficacy, school closures, and prophylactic absenteeism using published data. The 2004 UK economy (the most up to date available with suitable economic data). The economic impact of various scenarios with different pandemic severity, vaccination, school closure, and prophylactic absenteeism specified in terms of gross domestic product, output from different economic sectors, and equivalent variation. The costs related to illness alone ranged between 0.5% and 1.0% of gross domestic product ( pound8.4bn to pound16.8bn) for low fatality scenarios, 3.3% and 4.3% ( pound55.5bn to pound72.3bn) for high fatality scenarios, and larger still for an extreme pandemic. School closure increases the economic impact, particularly for mild pandemics. If widespread behavioural change takes place and there is large scale prophylactic absence from work, the economic impact would be notably increased with few health benefits. Vaccination with a pre-pandemic vaccine could save 0.13% to 2.3% of gross domestic product ( pound2.2bn to pound38.6bn); a single dose of a matched vaccine could save 0.3% to 4.3% ( pound5.0bn to pound72.3bn); and two doses of a matched vaccine could limit the overall economic impact to about 1% of gross domestic product for all disease scenarios. Balancing school closure against "business as usual" and obtaining sufficient stocks of effective vaccine are more important factors in determining the economic impact of an influenza pandemic than is the disease itself. Prophylactic absence from work in response to fear of infection can add considerably to the economic impact.

  17. A general non-equilibrium framework for the parameterization of positive and negative feedbacks in atmospheric systems

    Science.gov (United States)

    Garrett, T. J.

    2012-12-01

    For any identifiable system, regardless of its complexity or scale, evolution can be treated as a spontaneous thermodynamic response to a local convergence of down-gradient material flows. In climate studies, examples of identifiable systems might include cloud cover or the global incidence of temperatures warmer than a certain threshold. Here it is shown how the time-dependent evolution of such systems is constrained by positive and negative feedbacks that fall into a few mathematically distinct modes. In general, evolution depends on the time integral of past flows and the current availability of material and energetic resources. More specifically, negative feedbacks arise from the depletion or predation of the material and potential energy reservoirs that supply the system. Positive feedbacks are due to either new reservoir "discovery" or system expansion into existing reservoirs. When positive feedbacks dominate, the time dependent response of system growth falls into a few clearly identifiable behaviors that include a law of diminishing returns, logistic behavior, and, if reservoirs are expanding very rapidly, unstable super-exponential or explosive growth. For open systems (e.g. radiative flows in our atmosphere) that have a resolved sink as well as a source, oscillatory behavior emerges and can be characterized in terms of a slightly modified form of the predator-prey equations commonly employed in ecology. The perturbation formulation of these equations is equivalent to a damped simple harmonic oscillator. Specific examples of non-equilibrium positive and negative feedback response can be described for the sudden development of rain and the oscillatory evolution of open-celled stratocumulus cloud decks.

  18. A relativistic gravity train

    Science.gov (United States)

    Parker, Edward

    2017-08-01

    A nonrelativistic particle released from rest at the edge of a ball of uniform charge density or mass density oscillates with simple harmonic motion. We consider the relativistic generalizations of these situations where the particle can attain speeds arbitrarily close to the speed of light; generalizing the electrostatic and gravitational cases requires special and general relativity, respectively. We find exact closed-form relations between the position, proper time, and coordinate time in both cases, and find that they are no longer harmonic, with oscillation periods that depend on the amplitude. In the highly relativistic limit of both cases, the particle spends almost all of its proper time near the turning points, but almost all of the coordinate time moving through the bulk of the ball. Buchdahl's theorem imposes nontrivial constraints on the general-relativistic case, as a ball of given density can only attain a finite maximum radius before collapsing into a black hole. This article is intended to be pedagogical, and should be accessible to those who have taken an undergraduate course in general relativity.

  19. What is "Relativistic Canonical Quantization"?

    OpenAIRE

    Arbatsky, D. A.

    2005-01-01

    The purpose of this review is to give the most popular description of the scheme of quantization of relativistic fields that was named relativistic canonical quantization (RCQ). I do not give here the full exact account of this scheme. But with the help of this review any physicist, even not a specialist in the relativistic quantum theory, will be able to get a general view of the content of RCQ, of its connection with other known approaches, of its novelty and of its fruitfulness.

  20. 电子商务生产与消费的一般均衡模型%General equilibrium model of production and consumption of e-commerce

    Institute of Scientific and Technical Information of China (English)

    王凌晖

    2014-01-01

    As a new trading pattern, the development of e-commerce follows certain rules. Consumption equilibrium model of consumers and production equilibrium model of producers were analyzed from the perspective of behavior selection, which showed that both parties seek to maximize their own utility. On this basis, the interplay of the two sides was studied, and a general equilib-rium model of e-commerce consumption and of production was constructed. Starting from a technical diminishing marginal product of e-commerce technology, an in-depth study was carried out on win-win mechanism and equilibrium in the general equilibrium model. The affecting factors of this equilibrium state and the eventual utility level of the two sides were then discussed.%电子商务作为一种新型的交易模式,其自身发展会遵循一定的规律。从交易双方的行为选择角度分析了消费者的消费均衡模型和生产者的生产均衡模型,表现为交易双方都会追求自身的效用最大化。以此为基础,对双方的相互影响关系进行了研究,构建了电子商务消费与生产的一般均衡模型,并从电子商务技术的技术边际产出递减规律入手,深入研究了一般均衡模型中的共赢机制和均衡状态。探讨了这种均衡状态的影响因素和双方的最终效用水平。

  1. A reaction-based paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan [ORNL; Yeh, Gour-Tsyh [University of Central Florida, Orlando; Parker, Jack C [ORNL; Brooks, Scott C [ORNL; Pace, Molly [ORNL; Kim, Young Jin [ORNL; Jardine, Philip M [ORNL; Watson, David B [ORNL

    2007-01-01

    This paper presents a reaction-based water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M partial differential equations (PDEs). Decomposition via Gauss-Jordan column reduction of the reaction network transforms M species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing NE equilibrium reactions and a set of reactive transport equations of M-NE kinetic-variables involving no equilibrium reactions (a kinetic-variable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kinetic-variables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions.

  2. A reaction-based paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions

    Science.gov (United States)

    Zhang, Fan; Yeh, Gour-Tsyh; Parker, Jack C.; Brooks, Scott C.; Pace, Molly N.; Kim, Young-Jin; Jardine, Philip M.; Watson, David B.

    2007-06-01

    This paper presents a reaction-based water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M partial differential equations (PDEs). Decomposition via Gauss-Jordan column reduction of the reaction network transforms M species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing NE equilibrium reactions and a set of reactive transport equations of M- NE kinetic-variables involving no equilibrium reactions (a kinetic-variable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kinetic-variables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions.

  3. Relativistic effects in atom gravimeters

    Science.gov (United States)

    Tan, Yu-Jie; Shao, Cheng-Gang; Hu, Zhong-Kun

    2017-01-01

    Atom interferometry is currently developing rapidly, which is now reaching sufficient precision to motivate laboratory tests of general relativity. Thus, it is extremely significant to develop a general relativistic model for atom interferometers. In this paper, we mainly present an analytical derivation process and first give a complete vectorial expression for the relativistic interferometric phase shift in an atom interferometer. The dynamics of the interferometer are studied, where both the atoms and the light are treated relativistically. Then, an appropriate coordinate transformation for the light is performed crucially to simplify the calculation. In addition, the Bordé A B C D matrix combined with quantum mechanics and the "perturbation" approach are applied to make a methodical calculation for the total phase shift. Finally, we derive the relativistic phase shift kept up to a sensitivity of the acceleration ˜1 0-14 m/s 2 for a 10 -m -long atom interferometer.

  4. Relativistic models of a class of compact objects

    Indian Academy of Sciences (India)

    Rumi Deb; Bikash Chandra Paul; Ramesh Tikekar

    2012-08-01

    A class of general relativistic solutions in isotropic spherical polar coordinates which describe compact stars in hydrostatic equilibrium are discussed. The stellar models obtained here are characterized by four parameters, namely, , , and of geometrical significance related to the inhomogeneity of the matter content of the star. The stellar models obtained using the solutions are physically viable for a wide range of values of the parameters. The physical features of the compact objects taken up here are studied numerically for a number of admissible values of the parameters. Observational stellar mass data are used to construct suitable models of the compact stars.

  5. Extended quasiparticle approximation for relativistic electrons in plasmas

    Directory of Open Access Journals (Sweden)

    V.G.Morozov

    2006-01-01

    Full Text Available Starting with Dyson equations for the path-ordered Green's function, it is shown that the correlation functions for relativistic electrons (positrons in a weakly coupled non-equilibrium plasmas can be decomposed into sharply peaked quasiparticle parts and off-shell parts in a rather general form. To leading order in the electromagnetic coupling constant, this decomposition yields the extended quasiparticle approximation for the correlation functions, which can be used for the first principle calculation of the radiation scattering rates in QED plasmas.

  6. Gravitation relativiste

    CERN Document Server

    Hakim, Rémi

    1994-01-01

    Il existe à l'heure actuelle un certain nombre de théories relativistes de la gravitation compatibles avec l'expérience et l'observation. Toutefois, la relativité générale d'Einstein fut historiquement la première à fournir des résultats théoriques corrects en accord précis avec les faits.

  7. Relativistic diffusive motion in random electromagnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Haba, Z, E-mail: zhab@ift.uni.wroc.pl [Institute of Theoretical Physics, University of Wroclaw, 50-204 Wroclaw, Plac Maxa Borna 9 (Poland)

    2011-08-19

    We show that the relativistic dynamics in a Gaussian random electromagnetic field can be approximated by the relativistic diffusion of Schay and Dudley. Lorentz invariant dynamics in the proper time leads to the diffusion in the proper time. The dynamics in the laboratory time gives the diffusive transport equation corresponding to the Juettner equilibrium at the inverse temperature {beta}{sup -1} = mc{sup 2}. The diffusion constant is expressed by the field strength correlation function (Kubo's formula).

  8. Relativistic Astrophysics

    Science.gov (United States)

    Jones, Bernard J. T.; Markovic, Dragoljub

    1997-06-01

    Preface; Prologue: Conference overview Bernard Carr; Part I. The Universe At Large and Very Large Redshifts: 2. The size and age of the Universe Gustav A. Tammann; 3. Active galaxies at large redshifts Malcolm S. Longair; 4. Observational cosmology with the cosmic microwave background George F. Smoot; 5. Future prospects in measuring the CMB power spectrum Philip M. Lubin; 6. Inflationary cosmology Michael S. Turner; 7. The signature of the Universe Bernard J. T. Jones; 8. Theory of large-scale structure Sergei F. Shandarin; 9. The origin of matter in the universe Lev A. Kofman; 10. New guises for cold-dark matter suspects Edward W. Kolb; Part II. Physics and Astrophysics Of Relativistic Compact Objects: 11. On the unification of gravitational and inertial forces Donald Lynden-Bell; 12. Internal structure of astrophysical black holes Werner Israel; 13. Black hole entropy: external facade and internal reality Valery Frolov; 14. Accretion disks around black holes Marek A. Abramowicz; 15. Black hole X-ray transients J. Craig Wheeler; 16. X-rays and gamma rays from active galactic nuclei Roland Svensson; 17. Gamma-ray bursts: a challenge to relativistic astrophysics Martin Rees; 18. Probing black holes and other exotic objects with gravitational waves Kip Thorne; Epilogue: the past and future of relativistic astrophysics Igor D. Novikov; I. D. Novikov's scientific papers and books.

  9. Properties of relativistically rotating quark stars

    Science.gov (United States)

    Zhou, Enping

    2017-06-01

    In this work, quasi-equilibrium models of rapidly rotating triaxially deformed quark stars are computed in general relativistic gravity, assuming a conformally flat spatial geometry (Isenberg-Wilson-Mathews formulation) and a polynomial equation of state. Especially, since we are using a full 3-D numerical relativity initial data code, we are able to consider the triaxially deformed rotating quark stars at very high spins. Such triaxially deformed stars are possible gravitational radiation sources detectable by ground based gravitational wave observatories. Additionally, the bifurcation from axisymmetric rotating sequence to triaxially rotating sequence hints a more realistic spin up limit for rotating compact stars compared with the mass-shedding limit. With future observations such as sub-millisecond pulsars, we could possibly distinguish between equation of states of compact stars, thus better understanding strong interaction in the low energy regime.

  10. Parameterized Radiative Convective Equilibrium Across a Range of Domains: A Unifying Tool for General Circulation Models and High Resolution Models

    Science.gov (United States)

    Silvers, L. G.; Stevens, B. B.; Mauritsen, T.; Marco, G. A.

    2015-12-01

    The characteristics of clouds in General Circulation Models (GCMs) need to be constrained in a consistent manner with theory, observations, and high resolution models (HRMs). One way forward is to base improvements of parameterizations on high resolution studies which resolve more of the important dynamical motions and allow for less parameterizations. This is difficult because of the numerous differences between GCMs and HRMs, both technical and theoretical. Century long simulations at resolutions of 20-250 km on a global domain are typical of GCMs while HRMs often simulate hours at resolutions of 0.1km-5km on domains the size of a single GCM grid cell. The recently developed mode ICON provides a flexible framework which allows many of these difficulties to be overcome. This study uses the ICON model to compute SST perturbation simulations on multiple domains in a state of Radiative Convective Equilibrium (RCE) with parameterized convection. The domains used range from roughly the size of Texas to nearly half of Earth's surface area. All simulations use a doubly periodic domain with an effective distance between cell centers of 13 km and are integrated to a state of statistical stationarity. The primary analysis examines the mean characteristics of the cloud related fields and the feedback parameter of the simulations. It is shown that the simulated atmosphere of a GCM in RCE is sufficiently similar across a range of domain sizes to justify the use of RCE to study both a GCM and a HRM on the same domain with the goal of improved constraints on the parameterized clouds. The simulated atmospheres are comparable to what could be expected at midday in a typical region of Earth's tropics under calm conditions. In particular, the differences between the domains are smaller than differences which result from choosing different physics schemes. Significant convective organization is present on all domain sizes with a relatively high subsidence fraction. Notwithstanding

  11. Thermodynamics of polarized relativistic matter

    Science.gov (United States)

    Kovtun, Pavel

    2016-07-01

    We give the free energy of equilibrium relativistic matter subject to external gravitational and electromagnetic fields, to one-derivative order in the gradients of the external fields. The free energy allows for a straightforward derivation of bound currents and bound momenta in equilibrium. At leading order, the energy-momentum tensor admits a simple expression in terms of the polarization tensor. Beyond the leading order, electric and magnetic polarization vectors are intrinsically ambiguous. The physical effects of polarization, such as the correlation between the magneto-vortically induced surface charge and the electro-vortically induced surface current, are not ambiguous.

  12. Thermodynamics of polarized relativistic matter

    CERN Document Server

    Kovtun, Pavel

    2016-01-01

    We give the free energy of equilibrium relativistic matter subject to external gravitational and electromagnetic fields, to one-derivative order in the gradients of the external fields. The free energy allows for a straightforward derivation of bound currents and bound momenta in equilibrium. At leading order, the energy-momentum tensor admits a simple expression in terms of the polarization tensor. Beyond the leading order, electric and magnetic polarization vectors are intrinsically ambiguous. The physical effects of polarization, such as the correlation between the magneto-vortically induced surface charge and the electro-vortically induced surface current, are not ambiguous.

  13. Equilibrium configurations of fluids and their stability in higher dimensions

    CERN Document Server

    Cardoso, V; Cardoso, Vitor; Gualtieri, Leonardo

    2006-01-01

    We study equilibrium shapes, stability and possible bifurcation diagrams of fluids in higher dimensions, held together by either surface tension or self-gravity. We consider the equilibrium shape and stability problem of self-gravitating spheroids, establishing the formalism to generalize the MacLaurin sequence to higher dimensions. We show that such simple models, of interest on their own, also provide accurate descriptions of their general relativistic relatives with event horizons. The examples worked out here hint at some model-independent dynamics, and thus at some universality: smooth objects seem always to be well described by both ``replicas'' (either self-gravity or surface tension). As an example, we exhibit an instability afflicting self-gravitating (Newtonian) fluid cylinders. This instability is the exact analogue, within Newtonian gravity, of the Gregory-Laflamme instability in general relativity. Another example considered is a self-gravitating Newtonian torus made of a homogeneous incompressib...

  14. A Study of the Role of Government in Income and Wealth Distribution by Integrating the Walrasian General Equilibrium and Neoclassical Growth Theories

    Directory of Open Access Journals (Sweden)

    Wei-Bin Zhang

    2014-01-01

    Full Text Available This paper proposes a growth model of heterogeneous households with economic structure, wealth accumulation, endogenous labour supply, and tax rates. The paper is focused on effects of redistribution policies on income and wealth distribution, economic structure and economic growth. The paper integrates the Walrasian general equilibrium theory and neoclassical economic growth within a comprehensive framework. We overcome the controversial features in the two traditional theories by applying an alternative approach to households. We build an analytical framework for a disaggregated and microfounded general theory of economic growth with endogenous wealth accumulation. We simulate the model to identify equilibrium, stability and to plot the motion of the dynamic system with three groups. We also carry out comparative dynamic analysis with regard to the lump tax, human capital and propensity to use leisure time.

  15. Modified Hybrid Block Iterative Algorithm for Convex Feasibility Problems and Generalized Equilibrium Problems for Uniformly Quasi-ϕ-Asymptotically Nonexpansive Mappings

    Directory of Open Access Journals (Sweden)

    Siwaporn Saewan

    2010-01-01

    Full Text Available We introduce a modified block hybrid projection algorithm for solving the convex feasibility problems for an infinite family of closed and uniformly quasi-ϕ-asymptotically nonexpansive mappings and the set of solutions of the generalized equilibrium problems. We obtain a strong convergence theorem for the sequences generated by this process in a uniformly smooth and strictly convex Banach space with Kadec-Klee property. The results presented in this paper improve and extend some recent results.

  16. Generalized Mixed Equilibrium Problems and Fixed Point Problem for a Countable Family of Total Quasi-ϕ-Asymptotically Nonexpansive Mappings in Banach Spaces

    Directory of Open Access Journals (Sweden)

    Jinhua Zhu

    2012-01-01

    finding a common element of the set of solutions for a system of generalized mixed equilibrium problems and the set of common fixed points for a countable family of total quasi-ϕ-asymptotically nonexpansive mappings. Under suitable conditions some strong convergence theorems are established in an uniformly smooth and strictly convex Banach space with Kadec-Klee property. The results presented in the paper improve and extend some recent results.

  17. The impact of the trade liberalization on the women work: Comparative analyzes between the South Africa and the Ethiopia with an impact of the general equilibrium calculable

    Directory of Open Access Journals (Sweden)

    Lulit Mitik

    2008-01-01

    Full Text Available The effects of trade liberalization on female labor depend on a country′s socio-economic and employment sector characteristics. A Gender-aware computable general equilibrium model is applied to Ethiopia and South Africa from a comparative perspective. Tariff reduction results in opposite outcomes regarding gender-based wage and labor market participation inequalities in the two countries due to their structural differences in men′s and women′s employment.

  18. The U.S. Market for Higher Education: A General Equilibrium Analysis of State and Private Colleges and Public Funding Policies

    OpenAIRE

    2013-01-01

    We develop a general equilibrium model of the market for undergraduate higher education that captures the coexistence of public and private colleges, the large degree of quality differentiation among them, and the tuition and admission policies that emerge from their competition for students. The calibrated version of the model matches well the aggregate characteristics of U.S. higher education including college attendance in public and private schools, tuition levels, and the distribution of...

  19. Relativistic models of magnetars: the twisted-torus magnetic field configuration

    CERN Document Server

    Ciolfi, R; Gualtieri, L; Pons, J A

    2009-01-01

    We find general relativistic solutions of equilibrium magnetic field configurations in magnetars, extending previous results of Colaiuda et al. (2008). Our method is based on the solution of the relativistic Grad-Shafranov equation, to which Maxwell's equations can be reduced in some limit. We obtain equilibrium solutions with the toroidal magnetic field component confined into a finite region inside the star, and the poloidal component extending to the exterior. These so-called twisted-torus configurations have been found to be the final outcome of dynamical simulations in the framework of Newtonian gravity, and appear to be more stable than other configurations. The solutions include higher order multipoles, which are coupled to the dominant dipolar field. We use arguments of minimal energy to constrain the ratio of the toroidal to the poloidal field.

  20. Does The Principle Of Equivalence Prevent Trapped Surfaces From Being Formed In The General Relativistic Collapse Process?

    CERN Document Server

    Leiter, D; Robertson, S; Leiter, Darryl; Mitra, Abhas; Robertson, Stanley

    2001-01-01

    It has been recently shown (Mitra, 2000 - astro-ph/9910408) that the timelike spherical collapse of a radiating, physical fluid in General Relativity, as seen by an interior co-moving observer at rest in the physical fluid, does not permit formation of ``trapped surfaces''. This followed from the fact that the formation of a trapped surface in a physical fluid would cause the timelike world lines of the collapsing fluid to become null at the would be trapped surface, thus violating the Principle of Equivalence in General Theory of Relativity. In this paper we generalize and extend this result by studying the problem from the point of view of the exterior Vaidya metric of a collapsing radiating fluid as seen by an exterior stationary observer, and find that the "no trapped surface condition" becomes g00 > 0 consistent with that obtained for the interior co-moving metric. Since we have shown that the Principle of Equivalence prevents trapped surfaces from being formed in collapsing, radiating objects, then true...

  1. Relativistic gravity gradiometry

    Science.gov (United States)

    Bini, Donato; Mashhoon, Bahram

    2016-12-01

    In general relativity, relativistic gravity gradiometry involves the measurement of the relativistic tidal matrix, which is theoretically obtained from the projection of the Riemann curvature tensor onto the orthonormal tetrad frame of an observer. The observer's 4-velocity vector defines its local temporal axis and its local spatial frame is defined by a set of three orthonormal nonrotating gyro directions. The general tidal matrix for the timelike geodesics of Kerr spacetime has been calculated by Marck [Proc. R. Soc. A 385, 431 (1983)]. We are interested in the measured components of the curvature tensor along the inclined "circular" geodesic orbit of a test mass about a slowly rotating astronomical object of mass M and angular momentum J . Therefore, we specialize Marck's results to such a "circular" orbit that is tilted with respect to the equatorial plane of the Kerr source. To linear order in J , we recover the gravitomagnetic beating phenomenon [B. Mashhoon and D. S. Theiss, Phys. Rev. Lett. 49, 1542 (1982)], where the beat frequency is the frequency of geodetic precession. The beat effect shows up as a special long-period gravitomagnetic part of the relativistic tidal matrix; moreover, the effect's short-term manifestations are contained in certain post-Newtonian secular terms. The physical interpretation of this effect is briefly discussed.

  2. Galilean relativistic fluid mechanics

    CERN Document Server

    Ván, Péter

    2015-01-01

    Single component Galilean-relativistic (nonrelativistic) fluids are treated independently of reference frames. The basic fields are given, their balances, thermodynamic relations and the entropy production is calculated. The usual relative basic fields, the mass, momentum and energy densities, the diffusion current density, the pressure tensor and the heat flux are the time- and spacelike components of the third order mass-momentum-energy density tensor according to a velocity field. The transformation rules of the basic fields are derived and prove that the non-equilibrium thermodynamic background theory, that is the Gibbs relation, extensivity condition and the entropy production is absolute, that is independent of the reference frame and also of the fluid velocity. --- Az egykomponensu Galilei-relativisztikus (azaz nemrelativisztikus) disszipativ folyadekokat vonatkoztatasi rendszertol fuggetlenul targyaljuk. Megadjuk az alapmennyisegeket, ezek merlegeit, a termodinamikai osszefuggeseket es kiszamoljuk az ...

  3. Large-scale parallel configuration interaction. I. Nonrelativistic and scalar-relativistic general active space implementation with application to (Rb-Ba)+.

    Science.gov (United States)

    Knecht, Stefan; Jensen, Hans Jorgen Aa; Fleig, Timo

    2008-01-07

    We present a parallel implementation of a string-driven general active space configuration interaction program for nonrelativistic and scalar-relativistic electronic-structure calculations. The code has been modularly incorporated in the DIRAC quantum chemistry program package. The implementation is based on the message passing interface and a distributed data model in order to efficiently exploit key features of various modern computer architectures. We exemplify the nearly linear scalability of our parallel code in large-scale multireference configuration interaction (MRCI) calculations, and we discuss the parallel speedup with respect to machine-dependent aspects. The largest sample MRCI calculation includes 1.5x10(9) Slater determinants. Using the new code we determine for the first time the full short-range electronic potentials and spectroscopic constants for the ground state and for eight low-lying excited states of the weakly bound molecular system (Rb-Ba)+ with the spin-orbit-free Dirac formalism and using extensive uncontracted basis sets. The time required to compute to full convergence these electronic states for (Rb-Ba)+ in a single-point MRCI calculation correlating 18 electrons and using 16 cores was reduced from more than 10 days to less than 1 day.

  4. Generally relativistical Tetrode-Weyl-Fock-Ivanenko formalism and behaviour of quantum-mechanical particles of spin 1/2 in the Abelian monopole field

    CERN Document Server

    Redkov, V M

    1998-01-01

    Some attention in the literature has been given to the case of a particle of spin 1/2 on the background of the external monopole potential. Some aspects of this problem are reexamined here. The primary technical novelty is that the tetrad generally relativistic method of Tetrode-Weyl-Fock-Ivanenko for describing a spinor particle is exploited. The choice of the formalism has turned out to be of great fruitfulness for examining the system. It is matter that, as known, the use of a special spherical tetrad in the theory of a spin 1/2 particle had led Schrodinger to a basis of remarkable features. The basis has been used with great efficiency by Pauli in his investigation on the pro- blem of allowed spherically symmetric wave functions in quantum mechanics. For our purposes, just several simple rules extracted from the much more com- prehensive Pauli's analysis will be quite sufficient; those are almost mnemo- nic working regulations. So, one may remember some very primary facts of D- functions theory and then p...

  5. Relativistic and non-relativistic geodesic equations

    Energy Technology Data Exchange (ETDEWEB)

    Giambo' , R.; Mangiarotti, L.; Sardanashvily, G. [Camerino Univ., Camerino, MC (Italy). Dipt. di Matematica e Fisica

    1999-07-01

    It is shown that any dynamic equation on a configuration space of non-relativistic time-dependent mechanics is associated with connections on its tangent bundle. As a consequence, every non-relativistic dynamic equation can be seen as a geodesic equation with respect to a (non-linear) connection on this tangent bundle. Using this fact, the relationships between relativistic and non-relativistic equations of motion is studied.

  6. Characteristics of transonic spherical symmetric accretion flow in Schwarzschild-de Sitter and Schwarzschild anti-de Sitter backgrounds, in pseudo-general relativistic paradigm

    Science.gov (United States)

    Ghosh, Shubhrangshu; Banik, Prabir

    2015-07-01

    In this paper, we present a complete work on steady state spherically symmetric Bondi type accretion flow in the presence of cosmological constant (Λ) in both Schwarzschild-de Sitter (SDS) and Schwarzschild anti-de Sitter (SADS) backgrounds considering an isolated supermassive black hole (SMBH), with the inclusion of a simple radiative transfer scheme, in the pseudo-general relativistic paradigm. We do an extensive analysis on the transonic behavior of the Bondi type accretion flow onto the cosmological BHs including a complete analysis of the global parameter space and the stability of flow, and do a complete study of the global family of solutions for a generic polytropic flow. Bondi type accretion flow in SADS background renders multiplicity in its transonic behavior with inner "saddle" type and outer "center" type sonic points, with the transonic solutions forming closed loops or contours. There is always a limiting value for ∣Λ∣ up to which we obtain valid stationary transonic solutions, which correspond to both SDS and SADS geometries; this limiting value moderately increases with the increasing radiative efficiency of the flow, especially correspond to Bondi type accretion flow in SADS background. Repulsive Λ suppresses the Bondi accretion rate by an order of magnitude for relativistic Bondi type accretion flow for a certain range in temperature, and with a marginal increase in the Bondi accretion rate if the corresponding accretion flow occurs in SADS background. However, for a strongly radiative Bondi type accretion flow with high mass accretion rate, the presence of cosmological constant do not much influence the corresponding Bondi accretion rate of the flow. Our analysis show that the relic cosmological constant has a substantial effect on Bondi type accretion flow onto isolated SMBHs and their transonic solutions beyond length-scale of kiloparsecs, especially if the Bondi type accretion occurs onto the host supergiant ellipticals or central

  7. Relativistic Dynamics of Non-ideal Fluids: Viscous and heat-conducting fluids I. General Aspects and 3+1 Formulation for Nuclear Collisions

    CERN Document Server

    Muronga, A

    2007-01-01

    Relativistic non-ideal fluid dynamics is formulated in 3+1 space--time dimensions. The equations governing dissipative relativistic hydrodynamics are given in terms of the time and the 3-space quantities which correspond to those familiar from non-relativistic physics. Dissipation is accounted for by applying the causal theory of relativistic dissipative fluid dynamics. As a special case we consider a fluid without viscous/heat couplings in the causal system of transport/relaxation equations. For the study of physical systems we consider pure (1+1)-dimensional expansion in planar geometry, (1+1)-dimensional spherically symmetric ({\\em fireball}) expansion, (1+1)-dimensional cylindrically symmetric expansion and a (2+1)-dimensional expansion with cylindrical symmetry in the transverse plane ({\\em firebarell} expansion). The transport/relaxation equations are given in terms of the spatial components of the dissipative fluxes, since these are not independent. The choice for the independent components is analogou...

  8. Scattering in Relativistic Particle Mechanics.

    Science.gov (United States)

    de Bievre, Stephan

    The problem of direct interaction in relativistic particle mechanics has been extensively studied and a variety of models has been proposed avoiding the conclusions of the so-called no-interaction theorems. In this thesis we study scattering in the relativistic two-body problem. We use our results to analyse gauge invariance in Hamiltonian constraint models and the uniqueness of the symplectic structure in manifestly covariant relativistic particle mechanics. We first present a general geometric framework that underlies approaches to relativistic particle mechanics. This permits a model-independent and geometric definition of the notions of asymptotic completeness and of Moller and scattering operators. Subsequent analysis of these concepts divides into two parts. First, we study the kinematic properties of the scattering transformation, i.e. those properties that arise solely from the invariance of the theory under the Poincare group. We classify all canonical (symplectic) scattering transformations on the relativistic phase space for two free particles in terms of a single function of the two invariants of the theory. We show how this function is determined by the center of mass time delay and scattering angle and vice versa. The second part of our analysis of the relativistic two-body scattering problem is devoted to the dynamical properties of the scattering process. Hence, we turn to two approaches to relativistic particle mechanics: the Hamiltonian constraint models and the manifestly covariant formalism. Using general geometric arguments, we prove "gauge invariance" of the scattering transformation in the Todorov -Komar Hamiltonian constraint model. We conclude that the scattering cross sections of the Todorov-Komar models have the same angular dependence as their non-relativistic counterpart, irrespective of a choice of gauge. This limits the physical relevance of those models. We present a physically non -trivial Hamiltonian constraint model, starting from

  9. Spacetime Dependence of Local Temperature in Relativistic Quantum Field Theory

    CERN Document Server

    Gransee, Michael

    2016-01-01

    The spacetime dependence of the inverse temperature four-vector $\\boldsymbol{\\beta}$ for certain states of the quantized Klein-Gordon field on (parts of) Minkowski spacetime is discussed. These states fulfill a recently proposed version of the Kubo-Martin-Schwinger (KMS) boundary value condition, the so-called "local KMS (LKMS) condition". It turns out that, depending on the mass parameter $m\\geq 0$, any such state can be extended either (i) to a LKMS state on some forward or backward lightcone, with $\\boldsymbol{\\beta}$ depending linearily on spacetime, or (ii) to a thermal equilibrium (KMS) state on all of Minkowski space with constant $\\boldsymbol{\\beta}$. This parallels previously known results for local thermal equilibrium (LTE) states of the quantized Klein-Gordon field. Furthermore, in the case of a massless field our results point to a discrepancy with some classic results in general approaches to (non-quantum) relativistic thermodynamics.

  10. A nonextensive statistics approach for Langmuir waves in relativistic plasmas

    Directory of Open Access Journals (Sweden)

    V. Muñoz

    2006-01-01

    Full Text Available The nonextensive statistics formalism proposed by Tsallis has found many applications in systems with memory effects, long range spatial correlations, and in general whenever the phase space has fractal or multi-fractal structure. These features may appear naturally in turbulent or non-neutral plasmas. In fact, the equilibrium distribution functions which maximize the nonextensive entropy strongly resemble the non-Maxwellian particle distribution functions observed in space and laboratory and turbulent pure electron plasmas. In this article we apply the Tsallis entropy formalism to the problem of longitudinal oscillations in a proton-electron plasma. In particular, we study the equilibrium distribution function and the dispersion relation of longitudinal oscillations in a relativistic plasma, finding interesting differences with the nonrelativistic treatment.

  11. Modeling Non-Equilibrium Dynamics of a Discrete Probability Distribution: General Rate Equation for Maximal Entropy Generation in a Maximum-Entropy Landscape with Time-Dependent Constraints

    Directory of Open Access Journals (Sweden)

    Gian Paolo Beretta

    2008-08-01

    Full Text Available A rate equation for a discrete probability distribution is discussed as a route to describe smooth relaxation towards the maximum entropy distribution compatible at all times with one or more linear constraints. The resulting dynamics follows the path of steepest entropy ascent compatible with the constraints. The rate equation is consistent with the Onsager theorem of reciprocity and the fluctuation-dissipation theorem. The mathematical formalism was originally developed to obtain a quantum theoretical unification of mechanics and thermodinamics. It is presented here in a general, non-quantal formulation as a part of an effort to develop tools for the phenomenological treatment of non-equilibrium problems with applications in engineering, biology, sociology, and economics. The rate equation is also extended to include the case of assigned time-dependences of the constraints and the entropy, such as for modeling non-equilibrium energy and entropy exchanges.

  12. Modeling Non-Equilibrium Dynamics of a Discrete Probability Distribution: General Rate Equation for Maximal Entropy Generation in a Maximum-Entropy Landscape with Time-Dependent Constraints

    Science.gov (United States)

    Beretta, Gian P.

    2008-09-01

    A rate equation for a discrete probability distribution is discussed as a route to describe smooth relaxation towards the maximum entropy distribution compatible at all times with one or more linear constraints. The resulting dynamics follows the path of steepest entropy ascent compatible with the constraints. The rate equation is consistent with the Onsager theorem of reciprocity and the fluctuation-dissipation theorem. The mathematical formalism was originally developed to obtain a quantum theoretical unification of mechanics and thermodinamics. It is presented here in a general, non-quantal formulation as a part of an effort to develop tools for the phenomenological treatment of non-equilibrium problems with applications in engineering, biology, sociology, and economics. The rate equation is also extended to include the case of assigned time-dependences of the constraints and the entropy, such as for modeling non-equilibrium energy and entropy exchanges.

  13. Acceleration and Collimation of Relativistic Magnetohydrodynamic Disk Winds

    Science.gov (United States)

    Porth, Oliver; Fendt, Christian

    2010-02-01

    We perform axisymmetric relativistic magnetohydrodynamic simulations to investigate the acceleration and collimation of jets and outflows from disks around compact objects. Newtonian gravity is added to the relativistic treatment in order to establish the physical boundary condition of an underlying accretion disk in centrifugal and pressure equilibrium. The fiducial disk surface (respectively a slow disk wind) is prescribed as boundary condition for the outflow. We apply this technique for the first time in the context of relativistic jets. The strength of this approach is that it allows us to run a parameter study in order to investigate how the accretion disk conditions govern the outflow formation. Substantial effort has been made to implement a current-free, numerical outflow boundary condition in order to avoid artificial collimation present in the standard outflow conditions. Our simulations using the PLUTO code run for 500 inner disk rotations and on a physical grid size of 100 × 200 inner disk radii. The simulations evolve from an initial state in hydrostatic equilibrium and an initially force-free magnetic field configuration. Two options for the initial field geometries are applied—an hourglass-shaped potential magnetic field and a split monopole field. Most of our parameter runs evolve into a steady state solution which can be further analyzed concerning the physical mechanism at work. In general, we obtain collimated beams of mildly relativistic speed with Lorentz factors up to 6 and mass-weighted half-opening angles of 3-7 deg. The split-monopole initial setup usually results in less collimated outflows. The light surface of the outflow magnetosphere tends to align vertically—implying three relativistically distinct regimes in the flow—an inner subrelativistic domain close to the jet axis, a (rather narrow) relativistic jet and a surrounding subrelativistic outflow launched from the outer disk surface—similar to the spine-sheath structure

  14. Non competitive general equilibrium with endogenous price setting Equilibrio General no competitivo con formación endógena de precios

    Directory of Open Access Journals (Sweden)

    Castro Angélica

    2001-12-01

    Full Text Available

    This article presents an equilibrium concept that, contrary to the traditional walrasian one, allows for the unbalance between supply and demand in different markets, making easier the analysis of those situations in which they differ persistently, as in the case of the labor market. Furthermore, the process of price setting becomes endogenous and it is shown that an equilibrium with endogenous price setting is a particular case of an equilibrium of fixed prices. Toward the end some examples are presented which help us to sustain these arguments.

    En este artículo se presenta una 'concepción de equilibrio que, a
    diferencia de la tradicional walrasiana, permite el desbalance
    entre oferta y la demanda en los diferentes mercados facilitando
    el análisis de situaciones en las cuales estas difieren persistentemente, como en el caso del mercado laboral. De igual forma, se hace endógeno el proceso de formación de precios y se muestra que un equilibrio con formación de precios endógena es un caso particular de un equilibrio de precio fijo. Hacia el final se presentan algunos ejemplos que ayudan a sustentar estos argumentos.

  15. A General Relativistic Null Hypothesis Test with Event Horizon Telescope Observations of the black-hole shadow in Sgr A*

    CERN Document Server

    Psaltis, Dimitrios; Chan, Chi-Kwan; Marrone, Daniel P

    2014-01-01

    (Abridged) In General Relativity, the shadow cast by a black hole has a size that depends very weakly on its spin or the orientation of the observer. The half opening angle of the shadow is always equal to 5+-0.2 GM/Dc^2, where M is the mass of the black hole and D is its distance from the Earth. Therefore, measuring the size of the shadow of a black hole of known mass-to-distance ratio and verifying whether it is within the 4% predicted range constitutes a null hypothesis test of GR. We show that Sgr A* is the optimal target for performing this test with the Event Horizon Telescope. We use the results of monitoring of stellar orbits to show that the ratio M/D for Sgr A* is already known to an accuracy of ~6%. We investigate our prior knowledge of the scattering screen towards Sgr A, the effects of which will need to be corrected for in order for the black-hole shadow to appear sharp against the background emission. We argue that, even though the properties of the scattering ellipse at longer wavelengths are ...

  16. Thermal equilibrium and statistical thermometers in special relativity.

    Science.gov (United States)

    Cubero, David; Casado-Pascual, Jesús; Dunkel, Jörn; Talkner, Peter; Hänggi, Peter

    2007-10-26

    There is an intense debate in the recent literature about the correct generalization of Maxwell's velocity distribution in special relativity. The most frequently discussed candidate distributions include the Jüttner function as well as modifications thereof. Here we report results from fully relativistic one-dimensional molecular dynamics simulations that resolve the ambiguity. The numerical evidence unequivocally favors the Jüttner distribution. Moreover, our simulations illustrate that the concept of "thermal equilibrium" extends naturally to special relativity only if a many-particle system is spatially confined. They make evident that "temperature" can be statistically defined and measured in an observer frame independent way.

  17. Relativistic magnetohydrodynamics

    Science.gov (United States)

    Hernandez, Juan; Kovtun, Pavel

    2017-05-01

    We present the equations of relativistic hydrodynamics coupled to dynamical electromagnetic fields, including the effects of polarization, electric fields, and the derivative expansion. We enumerate the transport coefficients at leading order in derivatives, including electrical conductivities, viscosities, and thermodynamic coefficients. We find the constraints on transport coefficients due to the positivity of entropy production, and derive the corresponding Kubo formulas. For the neutral state in a magnetic field, small fluctuations include Alfvén waves, magnetosonic waves, and the dissipative modes. For the state with a non-zero dynamical charge density in a magnetic field, plasma oscillations gap out all propagating modes, except for Alfvén-like waves with a quadratic dispersion relation. We relate the transport coefficients in the "conventional" magnetohydrodynamics (formulated using Maxwell's equations in matter) to those in the "dual" version of magnetohydrodynamics (formulated using the conserved magnetic flux).

  18. Relativistic Achilles

    CERN Document Server

    Leardini, Fabrice

    2013-01-01

    This manuscript presents a problem on special relativity theory (SRT) which embodies an apparent paradox relying on the concept of simultaneity. The problem is represented in the framework of Greek epic poetry and structured in a didactic way. Owing to the characteristic properties of Lorenz transformations, three events which are simultaneous in a given inertial reference system, occur at different times in the other two reference frames. In contrast to the famous twin paradox, in the present case there are three, not two, different inertial observers. This feature provides a better framework to expose some of the main characteristics of SRT, in particular, the concept of velocity and the relativistic rule of addition of velocities.

  19. Geometric Models of the Relativistic Harmonic Oscillator

    CERN Document Server

    Cotaescu, I I

    1997-01-01

    A family of relativistic geometric models is defined as a generalization of the actual anti-de Sitter (1+1) model of the relativistic harmonic oscillator. It is shown that all these models lead to the usual harmonic oscillator in the non-relativistic limit, even though their relativistic behavior is quite different. Among quantum models we find a set of models with countable energy spectra, and another one having only a finite number of energy levels and in addition a continuous spectrum.

  20. Kinetic theory for nongeodesic particle motion Selfinteracting equilibrium states and effective viscous fluid pressures

    CERN Document Server

    Zimdahl, W; Zimdahl, Winfried; Balakin, Alexander B.

    1998-01-01

    The particles of a classical relativistic gas are supposed to move under the influence of a quasilinear (in the particle four-momenta), self-interacting force inbetween elastic, binary collisions. This force which is completely fixed by the equilibrium conditions of the gas, gives rise to an effective viscous pressure on the fluid phenomenological level. Earlier results concerning the possibility of accelerated expansion of the universe due to cosmological particle production are reinterpreted. A phenomenon such as power law inflation may be traced back to specific self-interacting forces keeping the particles of a gas universe in states of generalized equilibrium.