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Sample records for fragility stokes-einstein violation

  1. Communication: Fast dynamics perspective on the breakdown of the Stokes-Einstein law in fragile glassformers.

    Science.gov (United States)

    Puosi, F; Pasturel, A; Jakse, N; Leporini, D

    2018-04-07

    The breakdown of the Stokes-Einstein (SE) law in fragile glassformers is examined by Molecular-Dynamics simulations of atomic liquids and polymers and consideration of the experimental data concerning the archetypical ortho-terphenyl glassformer. All the four systems comply with the universal scaling between the viscosity (or the structural relaxation) and the Debye-Waller factor ⟨u 2 ⟩, the mean square amplitude of the particle rattling in the cage formed by the surrounding neighbors. It is found that the SE breakdown is scaled in a master curve by a reduced ⟨u 2 ⟩. Two approximated expressions of the latter, with no and one adjustable parameter, respectively, are derived.

  2. From Petrov-Einstein to Navier-Stokes

    Science.gov (United States)

    Lysov, Vyacheslav

    The fluid/gravity correspondence relates solutions of the incompressible Navier-Stokes equation to metrics which solve the Einstein equations. We propose propose two possible approaches to establish this correspondence: perturbative expansion for shear modes and large mean curvature expansion for algebraically special metrics. We show by explicit construction that for every solution of the incompressible Navier-Stokes equation in p+1 dimensions, there is an associated "dual" solution of the vacuum Einstein equations in p+2 dimensions. The dual geometry has an intrinsically flat time-like boundary segment whose extrinsic curvature is given by the stress tensor of the Navier-Stokes fluid. We consider a "near-horizon" limit in which hypersurface becomes highly accelerated. The near-horizon expansion in gravity is shown to be mathematically equivalent to the hydrodynamic expansion in fluid dynamics, and the Einstein equation reduces to the incompressible Navier-Stokes equation. It is shown that imposing a Petrov type I condition on the hypersurface geometry reduces the degrees of freedom in the extrinsic curvature to those of a fluid. Moreover, expanding around a limit in which the mean curvature of the embedding diverges, the leading-order Einstein constraint equations on hypersurface are shown to reduce to the non-linear incompressible Navier-Stokes equation for a fluid moving in hypersurface. We extend the fluid/gravity correspondence to include the magnetohydrodynamics/gravity correspondence, which translates solutions of the equations of magnetohydrodynamics (describing charged fluids) into geometries that satisfy the Einstein-Maxwell equations. We present an explicit example of this new correspondence in the context of flat Minkowski space. We show that a perturbative deformation of the Rindler wedge satisfies the Einstein-Maxwell equations provided that the parameters appearing in the expansion, which we interpret as fluid fields, satisfy the

  3. The Stokes-Einstein relation at moderate Schmidt number.

    Science.gov (United States)

    Balboa Usabiaga, Florencio; Xie, Xiaoyi; Delgado-Buscalioni, Rafael; Donev, Aleksandar

    2013-12-07

    The Stokes-Einstein relation for the self-diffusion coefficient of a spherical particle suspended in an incompressible fluid is an asymptotic result in the limit of large Schmidt number, that is, when momentum diffuses much faster than the particle. When the Schmidt number is moderate, which happens in most particle methods for hydrodynamics, deviations from the Stokes-Einstein prediction are expected. We study these corrections computationally using a recently developed minimally resolved method for coupling particles to an incompressible fluctuating fluid in both two and three dimensions. We find that for moderate Schmidt numbers the diffusion coefficient is reduced relative to the Stokes-Einstein prediction by an amount inversely proportional to the Schmidt number in both two and three dimensions. We find, however, that the Einstein formula is obeyed at all Schmidt numbers, consistent with linear response theory. The mismatch arises because thermal fluctuations affect the drag coefficient for a particle due to the nonlinear nature of the fluid-particle coupling. The numerical data are in good agreement with an approximate self-consistent theory, which can be used to estimate finite-Schmidt number corrections in a variety of methods. Our results indicate that the corrections to the Stokes-Einstein formula come primarily from the fact that the particle itself diffuses together with the momentum. Our study separates effects coming from corrections to no-slip hydrodynamics from those of finite separation of time scales, allowing for a better understanding of widely observed deviations from the Stokes-Einstein prediction in particle methods such as molecular dynamics.

  4. Compliance of the Stokes-Einstein model and breakdown of the Stokes-Einstein-Debye model for a urea-based supramolecular polymer of high viscosity.

    Science.gov (United States)

    Świergiel, Jolanta; Bouteiller, Laurent; Jadżyn, Jan

    2014-11-14

    Impedance spectroscopy was used for the study of the static and dynamic behavior of the electrical conductivity of a hydrogen-bonded supramolecular polymer of high viscosity. The experimental data are discussed in the frame of the Stokes-Einstein and Stokes-Einstein-Debye models. It was found that the translational movement of the ions is due to normal Brownian diffusion, which was revealed by a fulfillment of Ohm's law by the electric current and a strictly exponential decay of the current after removing the electric stimulus. The dependence of the dc conductivity on the viscosity of the medium fulfills the Stokes-Einstein model quite well. An extension of the model, by including in it the conductivity relaxation time, is proposed in this paper. A breakdown of the Stokes-Einstein-Debye model is revealed by the relations of the dipolar relaxation time to the viscosity and to the dc ionic conductivity. The importance of the C=O···H-N hydrogen bonds in that breakdown is discussed.

  5. Modified Einstein and Navier–Stokes Equations

    Science.gov (United States)

    Bulyzhenkov, I. É.

    2018-05-01

    The appearance of inertial rest mass-energy is associated with the kinematic slowing-down of time and with the vortex state of the elementary massive space with zero integral of its kinetic and potential energies. An analog of the Einstein equation is found for moving densities of a non-empty metric space in the concept of the Einstein-Infeld material field. The vector consequences of this tensor equation for a metric medium of overlapping elementary carriers of continuous mass-energies allow us to modify the Navier-Stokes equation under inertial motion of the matter of the nonlocal field in the nonrelativistic limit. The nonlocality of massenergy generates kinematic accelerations of feedback to Newtonian acceleration, which impedes asymptotic divergence of energy fluxes. Stabilization of inertial media by dynamic Bernoulli pressure corresponds to nonlocal self-organization of Einstein-Infeld non-empty space and invalidates Newtonian localization of masses in empty space.

  6. Modified Einstein and Navier-Stokes Equations

    Science.gov (United States)

    Bulyzhenkov, I. É.

    2018-05-01

    The appearance of inertial rest mass-energy is associated with the kinematic slowing-down of time and with the vortex state of the elementary massive space with zero integral of its kinetic and potential energies. An analog of the Einstein equation is found for moving densities of a non-empty metric space in the concept of the Einstein-Infeld material field. The vector consequences of this tensor equation for a metric medium of overlapping elementary carriers of continuous mass-energies allow us to modify the Navier-Stokes equation under inertial motion of the matter of the nonlocal field in the nonrelativistic limit. The nonlocality of massenergy generates kinematic accelerations of feedback to Newtonian acceleration, which impedes asymptotic divergence of energy fluxes. Stabilization of inertial media by dynamic Bernoulli pressure corresponds to nonlocal self-organization of Einstein-Infeld non-empty space and invalidates Newtonian localization of masses in empty space.

  7. Fragile-to-strong transition in liquid silica

    Science.gov (United States)

    Geske, Julian; Drossel, Barbara; Vogel, Michael

    2016-03-01

    We investigate anomalies in liquid silica with molecular dynamics simulations and present evidence for a fragile-to-strong transition at around 3100 K-3300 K. To this purpose, we studied the structure and dynamical properties of silica over a wide temperature range, finding four indicators of a fragile-to-strong transition. First, there is a density minimum at around 3000 K and a density maximum at 4700 K. The turning point is at 3400 K. Second, the local structure characterized by the tetrahedral order parameter changes dramatically around 3000 K from a higher-ordered, lower-density phase to a less ordered, higher-density phase. Third, the correlation time τ changes from an Arrhenius behavior below 3300 K to a Vogel-Fulcher-Tammann behavior at higher temperatures. Fourth, the Stokes-Einstein relation holds for temperatures below 3000 K, but is replaced by a fractional relation above this temperature. Furthermore, our data indicate that dynamics become again simple above 5000 K, with Arrhenius behavior and a classical Stokes-Einstein relation.

  8. Fragile-to-strong transition in liquid silica

    Directory of Open Access Journals (Sweden)

    Julian Geske

    2016-03-01

    Full Text Available We investigate anomalies in liquid silica with molecular dynamics simulations and present evidence for a fragile-to-strong transition at around 3100 K-3300 K. To this purpose, we studied the structure and dynamical properties of silica over a wide temperature range, finding four indicators of a fragile-to-strong transition. First, there is a density minimum at around 3000 K and a density maximum at 4700 K. The turning point is at 3400 K. Second, the local structure characterized by the tetrahedral order parameter changes dramatically around 3000 K from a higher-ordered, lower-density phase to a less ordered, higher-density phase. Third, the correlation time τ changes from an Arrhenius behavior below 3300 K to a Vogel-Fulcher-Tammann behavior at higher temperatures. Fourth, the Stokes-Einstein relation holds for temperatures below 3000 K, but is replaced by a fractional relation above this temperature. Furthermore, our data indicate that dynamics become again simple above 5000 K, with Arrhenius behavior and a classical Stokes-Einstein relation.

  9. Effective temperatures and the breakdown of the Stokes-Einstein relation for particle suspensions.

    Science.gov (United States)

    Mendoza, Carlos I; Santamaría-Holek, I; Pérez-Madrid, A

    2015-09-14

    The short- and long-time breakdown of the classical Stokes-Einstein relation for colloidal suspensions at arbitrary volume fractions is explained here by examining the role that confinement and attractive interactions play in the intra- and inter-cage dynamics executed by the colloidal particles. We show that the measured short-time diffusion coefficient is larger than the one predicted by the classical Stokes-Einstein relation due to a non-equilibrated energy transfer between kinetic and configuration degrees of freedom. This transfer can be incorporated in an effective kinetic temperature that is higher than the temperature of the heat bath. We propose a Generalized Stokes-Einstein relation (GSER) in which the effective temperature replaces the temperature of the heat bath. This relation then allows to obtain the diffusion coefficient once the viscosity and the effective temperature are known. On the other hand, the temporary cluster formation induced by confinement and attractive interactions of hydrodynamic nature makes the long-time diffusion coefficient to be smaller than the corresponding one obtained from the classical Stokes-Einstein relation. Then, the use of the GSER allows to obtain an effective temperature that is smaller than the temperature of the heat bath. Additionally, we provide a simple expression based on a differential effective medium theory that allows to calculate the diffusion coefficient at short and long times. Comparison of our results with experiments and simulations for suspensions of hard and porous spheres shows an excellent agreement in all cases.

  10. Transition from fractional to classical Stokes-Einstein behaviour in simple fluids.

    Science.gov (United States)

    Coglitore, Diego; Edwardson, Stuart P; Macko, Peter; Patterson, Eann A; Whelan, Maurice

    2017-12-01

    An optical technique for tracking single particles has been used to evaluate the particle diameter at which diffusion transitions from molecular behaviour described by the fractional Stokes-Einstein relationship to particle behaviour described by the classical Stokes-Einstein relationship. The results confirm a prior prediction from molecular dynamic simulations that there is a particle size at which transition occurs and show it is inversely dependent on concentration and viscosity but independent of particle density. For concentrations in the range 5 × 10 -3 to 5 × 10 -6  mg ml -1 and viscosities from 0.8 to 150 mPa s, the transition was found to occur in the diameter range 150-300 nm.

  11. Validity of the Stokes-Einstein relation in liquids: simple rules from the excess entropy.

    Science.gov (United States)

    Pasturel, A; Jakse, N

    2016-12-07

    It is becoming common practice to consider that the Stokes-Einstein relation D/T~ η -1 usually works for liquids above their melting temperatures although there is also experimental evidence for its failure. Here we investigate numerically this commonly-invoked assumption for simple liquid metals as well as for their liquid alloys. Using ab initio molecular dynamics simulations we show how entropy scaling relationships developed by Rosenfeld can be used to predict the conditions for the validity of the Stokes-Einstein relation in the liquid phase. Specifically, we demonstrate the Stokes-Einstein relation may break down in the liquid phase of some liquid alloys mainly due to the presence of local structural ordering as evidenced in their partial two-body excess entropies. Our findings shed new light on the understanding of transport properties of liquid materials and will trigger more experimental and theoretical studies since excess entropy and its two-body approximation are readily obtainable from standard experiments and simulations.

  12. Breakdown of the Stokes-Einstein Relation for the Rotational Diffusivity of Polymer Grafted Nanoparticles in Polymer Melts.

    Science.gov (United States)

    Maldonado-Camargo, Lorena; Rinaldi, Carlos

    2016-11-09

    We report observations of breakdown of the Stokes-Einstein relation for the rotational diffusivity of polymer-grafted spherical nanoparticles in polymer melts. The rotational diffusivity of magnetic nanoparticles coated with poly(ethylene glycol) dispersed in poly(ethylene glycol) melts was determined through dynamic magnetic susceptibility measurements of the collective rotation of the magnetic nanoparticles due to imposed time-varying magnetic torques. These measurements clearly demonstrate the existence of a critical molecular weight for the melt polymer, below which the Stokes-Einstein relation accurately describes the rotational diffusivity of the polymer-grafted nanoparticles and above which the Stokes-Einstein relation ceases to apply. This critical molecular weight was found to correspond to a chain contour length that approximates the hydrodynamic diameter of the nanoparticles.

  13. Incompressible Navier-Stokes equation from Einstein-Maxwell and Gauss-Bonnet-Maxwell theories

    International Nuclear Information System (INIS)

    Niu Chao; Tian Yu; Wu Xiaoning; Ling Yi

    2012-01-01

    The dual fluid description for a general cutoff surface at radius r=r c outside the horizon in the charged AdS black brane bulk space-time is investigated, first in the Einstein-Maxwell theory. Under the non-relativistic long-wavelength expansion with parameter ε, the coupled Einstein-Maxwell equations are solved up to O(ε 2 ). The incompressible Navier-Stokes equation with external force density is obtained as the constraint equation at the cutoff surface. For non-extremal black brane, the viscosity of the dual fluid is determined by the regularity of the metric fluctuation at the horizon, whose ratio to entropy density η/s is independent of both the cutoff r c and the black brane charge. Then, we extend our discussion to the Gauss-Bonnet-Maxwell case, where the incompressible Navier-Stokes equation with external force density is also obtained at a general cutoff surface. In this case, it turns out that the ratio η/s is independent of the cutoff r c but dependent on the charge density of the black brane.

  14. Violations of Einstein's Relativity: Motivations, Theory, and Phenomenology

    International Nuclear Information System (INIS)

    Lehnert, Ralf

    2011-01-01

    One of the most difficult questions in present-day physics concerns a fundamental theory of space, time, and matter that incorporates a consistent quantum description of gravity. There are various theoretical approaches to such a quantum-gravity theory. Nevertheless, experimental progress is hampered in this research field because many models predict deviations from established physics that are suppressed by some power of the Planck scale, which currently appears to be immeasurably small. However, tests of relativity theory provide one promising avenue to overcome this phenomeno-logical obstacle: many models for underlying physics can accommodate a small breakdown of Lorentz symmetry, and numerous feasible Lorentz-symmetry tests have Planck reach. Such mild violations of Einstein's relativity have therefore become the focus of recent research efforts. This mini course provides a brief survey of the key ideas in this research field and is geared at both experimentalists and theorists. In particular, several theoretical mechanisms leading to deviations from relativity theory are presented; the standard theoretical framework for relativity violations at currently accessible energy scales (i.e., the SME) is reviewed, and various present and near-future experimental efforts within this field are discussed.

  15. Stokes-Einstein relation for pure simple fluids

    Science.gov (United States)

    Cappelezzo, M.; Capellari, C. A.; Pezzin, S. H.; Coelho, L. A. F.

    2007-06-01

    The authors employed the equilibrium molecular dynamics technique to calculate the self-diffusion coefficient and the shear viscosity for simple fluids that obey the Lennard-Jones 6-12 potential in order to investigate the validity of the Stokes-Einstein (SE) relation for pure simple fluids. They performed calculations in a broad range of density and temperature in order to test the SE relation. The main goal of this work is to exactly calculate the constant, here denominated by α, present in the SE relation. Also, a modified SE relation where a fluid density is raised to a power in the usual expression is compared to the classical expression. According to the authors' simulations slip boundary conditions (α=4) can be satisfied in some state points. An intermediate value of α =5 was found in some regions of the phase diagram confirming the mode coupling theory. In addition depending on the phase diagram point and the definition of hydrodynamics radius, stick boundary condition (α=6) can be reproduced. The authors investigated the role of the hydrodynamic radius in the SE relation using three different definitions. The authors also present calculations for α in a hard-sphere system showing that the slip boundary conditions hold at very high density. They discuss possible explanations for their results and the role of the hydrodynamic radius for different definitions in the SE relation.

  16. Structural origin of fractional Stokes-Einstein relation in glass-forming liquids.

    Science.gov (United States)

    Pan, Shaopeng; Wu, Z W; Wang, W H; Li, M Z; Xu, Limei

    2017-01-06

    In many glass-forming liquids, fractional Stokes-Einstein relation (SER) is observed above the glass transition temperature. However, the origin of such phenomenon remains elusive. Using molecular dynamics simulations, we investigate the break- down of SER and the onset of fractional SER in a model of metallic glass-forming liquid. We find that SER breaks down when the size of the largest cluster consisting of trapped atoms starts to increase sharply at which the largest cluster spans half of the simulations box along one direction, and the fractional SER starts to follows when the largest cluster percolates the entire system and forms 3-dimentional network structures. Further analysis based on the percolation theory also confirms that percolation occurs at the onset of the fractional SER. Our results directly link the breakdown of the SER with structure inhomogeneity and onset of the fraction SER with percolation of largest clusters, thus provide a possible picture for the break- down of SER and onset of fractional SER in glass-forming liquids, which is is important for the understanding of the dynamic properties in glass-forming liquids.

  17. Radiating black holes in Einstein-Maxwell-dilaton theory and cosmic censorship violation

    International Nuclear Information System (INIS)

    Aniceto, Pedro; Pani, Paolo; Rocha, Jorge V.

    2016-01-01

    We construct exact, time-dependent, black hole solutions of Einstein-Maxwell-dilaton theory with arbitrary dilaton coupling, a. For a=1 this theory arises as the four-dimensional low-energy effective description of heterotic string theory. These solutions represent electrically charged, spherically symmetric black holes emitting or absorbing charged null fluids and generalize the Vaidya and Bonnor-Vaidya solutions of general relativity and of Einstein-Maxwell theory, respectively. The a=1 case stands out as special, in the sense that it is the only choice of the coupling that allows for a time-dependent dilaton field in this class of solutions. As a by-product, when a=1 we show that an electrically charged black hole in this theory can be overcharged by bombarding it with a stream of electrically charged null fluid, resulting in the formation of a naked singularity. This provides an example of cosmic censorship violation in an exact dynamical solution to low-energy effective string theory and in a case in which the total stress-energy tensor satisfies all energy conditions. When a≠1, our solutions necessarily have a time-independent scalar field and consequently cannot be overcharged.

  18. Radiating black holes in Einstein-Maxwell-dilaton theory and cosmic censorship violation

    Energy Technology Data Exchange (ETDEWEB)

    Aniceto, Pedro [CENTRA, Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa,Avenida Rovisco Pais 1, 1049 Lisboa (Portugal); Pani, Paolo [Dipartimento di Fisica, “Sapienza” Università di Roma & Sezione INFN Roma 1,Piazzale Aldo Moro 5, 00185 Roma (Italy); CENTRA, Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa,Avenida Rovisco Pais 1, 1049 Lisboa (Portugal); Rocha, Jorge V. [Departament de Física Fonamental, Institut de Ciències del Cosmos (ICCUB),Universitat de Barcelona,Martí i Franquès 1, E-08028 Barcelona (Spain)

    2016-05-19

    We construct exact, time-dependent, black hole solutions of Einstein-Maxwell-dilaton theory with arbitrary dilaton coupling, a. For a=1 this theory arises as the four-dimensional low-energy effective description of heterotic string theory. These solutions represent electrically charged, spherically symmetric black holes emitting or absorbing charged null fluids and generalize the Vaidya and Bonnor-Vaidya solutions of general relativity and of Einstein-Maxwell theory, respectively. The a=1 case stands out as special, in the sense that it is the only choice of the coupling that allows for a time-dependent dilaton field in this class of solutions. As a by-product, when a=1 we show that an electrically charged black hole in this theory can be overcharged by bombarding it with a stream of electrically charged null fluid, resulting in the formation of a naked singularity. This provides an example of cosmic censorship violation in an exact dynamical solution to low-energy effective string theory and in a case in which the total stress-energy tensor satisfies all energy conditions. When a≠1, our solutions necessarily have a time-independent scalar field and consequently cannot be overcharged.

  19. Validity of the Einstein Relation in Disordered Organic Semiconductors

    NARCIS (Netherlands)

    Wetzelaer, G. A. H.; Koster, L. J. A.; Blom, P. W. M.

    2011-01-01

    It is controversial whether energetic disorder in semiconductors is already sufficient to violate the classical Einstein relation, even in the case of thermal equilibrium. We demonstrate that the Einstein relation is violated only under nonequilibrium conditions due to deeply trapped carriers, as in

  20. Einstein's error

    International Nuclear Information System (INIS)

    Winterflood, A.H.

    1980-01-01

    In discussing Einstein's Special Relativity theory it is claimed that it violates the principle of relativity itself and that an anomalous sign in the mathematics is found in the factor which transforms one inertial observer's measurements into those of another inertial observer. The apparent source of this error is discussed. Having corrected the error a new theory, called Observational Kinematics, is introduced to replace Einstein's Special Relativity. (U.K.)

  1. The role of the dynamic crossover temperature and the arrest in glass-forming fluids.

    Science.gov (United States)

    Mallamace, F; Corsaro, C; Stanley, H E; Chen, S-H

    2011-09-01

    We discuss the role of the dynamic glass-forming fragile-to-strong crossover (FSC) in supercooled liquids. In the FSC, significant dynamic changes such as the decoupling (the violation of the Stokes-Einstein relation) of homologous transport parameters, e.g., the density relaxation time τ and the viscosity η, occur at a characteristic temperature T(c). We study the FSC using a scaling law approach. In particular, we use both forms of the mode-coupling theory (MCT): the original (ideal) and the extended form, which explicitly describes energy hopping processes. We demonstrate that T(c) plays the most important physical role in understanding dynamic arrest processes.

  2. Einstein-Podolsky-Rosen-Bohm experiment and Bell inequality violation using Type 2 parametric down conversion

    Science.gov (United States)

    Kiess, Thomas E.; Shih, Yan-Hua; Sergienko, A. V.; Alley, Carroll O.

    1994-01-01

    We report a new two-photon polarization correlation experiment for realizing the Einstein-Podolsky-Rosen-Bohm (EPRB) state and for testing Bell-type inequalities. We use the pair of orthogonally-polarized light quanta generated in Type 2 parametric down conversion. Using 1 nm interference filters in front of our detectors, we observe from the output of a 0.5mm beta - BaB2O4 (BBO) crystal the EPRB correlations in coincidence counts, and measure an associated Bell inequality violation of 22 standard deviations. The quantum state of the photon pair is a polarization analog of the spin-1/2 singlet state.

  3. Beyond Gisin's Theorem and its Applications: Violation of Local Realism by Two-Party Einstein-Podolsky-Rosen Steering.

    Science.gov (United States)

    Chen, Jing-Ling; Su, Hong-Yi; Xu, Zhen-Peng; Wu, Yu-Chun; Wu, Chunfeng; Ye, Xiang-Jun; Żukowski, Marek; Kwek, L C

    2015-06-25

    We demonstrate here that for a given mixed multi-qubit state if there are at least two observers for whom mutual Einstein-Podolsky-Rosen steering is possible, i.e. each observer is able to steer the other qubits into two different pure states by spontaneous collapses due to von Neumann type measurements on his/her qubit, then nonexistence of local realistic models is fully equivalent to quantum entanglement (this is not so without this condition). This result leads to an enhanced version of Gisin's theorem (originally: all pure entangled states violate local realism). Local realism is violated by all mixed states with the above steering property. The new class of states allows one e.g. to perform three party secret sharing with just pairs of entangled qubits, instead of three qubit entanglements (which are currently available with low fidelity). This significantly increases the feasibility of having high performance versions of such protocols. Finally, we discuss some possible applications.

  4. Interferometer tests for quantum non-locality using Bose-Einstein condensates

    Energy Technology Data Exchange (ETDEWEB)

    Mullin, W J [Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Laloe, F [Laboratoire Kastler Brossel, ENS, UPMC, CNRS, 24 rue Lhomond, 75005 Paris (France)], E-mail: mullin@physics.umass.edu, E-mail: laloe@lkb.ens.fr

    2009-02-01

    In conventional Einstein-Rosen-Podolsky (EPR) experiments that violate local realism, particles are placed in very particular entangled states. We propose here to use two or three spinless Fock-state Bose-Einstein condensates as independent sources in interferometery experiments. While these states do not seem to be entangled, nevertheless we show that interferometers can be constructed that demonstrate a large variety of different violations local reality. We find violations of Bell inequalities, new Greenberger-Horne-Zeilinger (GHZ) contradictions, and Hardy impossibilities. These violations continue to arbitrarily large particle numbers. A necessary condition to observe the quantum effects is that all particles should be observed; if some are missed, the quantum effects disappear.

  5. Beyond Gisin’s Theorem and its Applications: Violation of Local Realism by Two-Party Einstein-Podolsky-Rosen Steering

    Science.gov (United States)

    Chen, Jing-Ling; Su, Hong-Yi; Xu, Zhen-Peng; Wu, Yu-Chun; Wu, Chunfeng; Ye, Xiang-Jun; Żukowski, Marek; Kwek, L. C.

    2015-01-01

    We demonstrate here that for a given mixed multi-qubit state if there are at least two observers for whom mutual Einstein-Podolsky-Rosen steering is possible, i.e. each observer is able to steer the other qubits into two different pure states by spontaneous collapses due to von Neumann type measurements on his/her qubit, then nonexistence of local realistic models is fully equivalent to quantum entanglement (this is not so without this condition). This result leads to an enhanced version of Gisin’s theorem (originally: all pure entangled states violate local realism). Local realism is violated by all mixed states with the above steering property. The new class of states allows one e.g. to perform three party secret sharing with just pairs of entangled qubits, instead of three qubit entanglements (which are currently available with low fidelity). This significantly increases the feasibility of having high performance versions of such protocols. Finally, we discuss some possible applications. PMID:26108704

  6. Bell Inequality, Einstein-Podolsky-Rosen Steering, and Quantum Metrology with Spinor Bose-Einstein Condensates

    Science.gov (United States)

    Wasak, Tomasz; Chwedeńczuk, Jan

    2018-04-01

    We propose an experiment, where the Bell inequality is violated in a many-body system of massive particles. The source of correlated atoms is a spinor F =1 Bose-Einstein condensate residing in an optical lattice. We characterize the complete procedure—the local operations, the measurements, and the inequality—necessary to run the Bell test. We show how the degree of violation of the Bell inequality depends on the strengths of the two-body correlations and on the number of scattered pairs. We show that the system can be used to demonstrate the Einstein-Podolsky-Rosen paradox. Also, the scattered pairs are an excellent many-body resource for the quantum-enhanced metrology. Our results apply to any multimode system where the spin-changing collision drives the scattering into separate regions. The presented inquiry shows that such a system is versatile as it can be used for the tests of nonlocality, quantum metrology, and quantum information.

  7. Bell Inequality, Einstein-Podolsky-Rosen Steering, and Quantum Metrology with Spinor Bose-Einstein Condensates.

    Science.gov (United States)

    Wasak, Tomasz; Chwedeńczuk, Jan

    2018-04-06

    We propose an experiment, where the Bell inequality is violated in a many-body system of massive particles. The source of correlated atoms is a spinor F=1 Bose-Einstein condensate residing in an optical lattice. We characterize the complete procedure-the local operations, the measurements, and the inequality-necessary to run the Bell test. We show how the degree of violation of the Bell inequality depends on the strengths of the two-body correlations and on the number of scattered pairs. We show that the system can be used to demonstrate the Einstein-Podolsky-Rosen paradox. Also, the scattered pairs are an excellent many-body resource for the quantum-enhanced metrology. Our results apply to any multimode system where the spin-changing collision drives the scattering into separate regions. The presented inquiry shows that such a system is versatile as it can be used for the tests of nonlocality, quantum metrology, and quantum information.

  8. Test of Einstein locality

    International Nuclear Information System (INIS)

    Roos, Matts

    1980-11-01

    Einstein locality imples that spacelike separated coherent quantum systems do not interfere, and that all interferences must propagate with at most the speed of light. It then follows that the reaction e + e - →K 0 antiK 0 must yield some Ksub(s)Ksuu(s) decays in apparent violation of P and C conservation. (author)

  9. On an uncorrelated jet model with Bose-Einstein statistics

    International Nuclear Information System (INIS)

    Bilic, N.; Dadic, I.; Martinis, M.

    1978-01-01

    Starting from the density of states of an ideal Bose-Einstein gas, an uncorrelated jet model with Bose-Einstein statistics has been formulated. The transition to continuum is based on the Touschek invariant measure. It has been shown that in this model average multiplicity increases logarithmically with total energy, while the inclusive distribution shows ln s violation of scaling. (author)

  10. Does the relativity principle violate?

    International Nuclear Information System (INIS)

    Barashenkov, V.S.

    1994-01-01

    Theoretical and experimental data about a possible existence in Nature of some preferred reference frame with a violation of the principle of relativity are considered. The Einstein's and Lorentz's points of view are compared. Although some experiments are known which, in opinion of their authors, indicate the relativity principle violation persuasive evidences supporting this conclusion are absent for the present. The proposals of new experiments in this region, particularly with electron spin precession, are discussed. 55 refs., 4 figs

  11. Strong binary pulsar constraints on Lorentz violation in gravity.

    Science.gov (United States)

    Yagi, Kent; Blas, Diego; Yunes, Nicolás; Barausse, Enrico

    2014-04-25

    Binary pulsars are excellent laboratories to test the building blocks of Einstein's theory of general relativity. One of these is Lorentz symmetry, which states that physical phenomena appear the same for all inertially moving observers. We study the effect of violations of Lorentz symmetry in the orbital evolution of binary pulsars and find that it induces a much more rapid decay of the binary's orbital period due to the emission of dipolar radiation. The absence of such behavior in recent observations allows us to place the most stringent constraints on Lorentz violation in gravity, thus verifying one of the cornerstones of Einstein's theory much more accurately than any previous gravitational observation.

  12. Strong Binary Pulsar Constraints on Lorentz Violation in Gravity

    CERN Document Server

    Yagi, Kent; Yunes, Nicolas; Barausse, Enrico

    2014-01-01

    Binary pulsars are excellent laboratories to test the building blocks of Einstein's theory of General Relativity. One of these is Lorentz symmetry which states that physical phenomena appear the same for all inertially moving observers. We study the effect of violations of Lorentz symmetry in the orbital evolution of binary pulsars and find that it induces a much more rapid decay of the binary's orbital period due to the emission of dipolar radiation. The absence of such behavior in recent observations allows us to place the most stringent constraints on Lorentz violation in gravity, thus verifying one of the cornerstones of Einstein's theory much more accurately than any previous gravitational observation.

  13. On Certain Conceptual Anomalies in Einstein's Theory of Relativity

    Directory of Open Access Journals (Sweden)

    Crothers S. J.

    2008-01-01

    Full Text Available There are a number of conceptual anomalies occurring in the Standard exposition of Einstein's Theory of Relativity. These anomalies relate to issues in both mathematics and in physics and penetrate to the very heart of Einstein's theory. This paper reveals and amplifies a few such anomalies, including the fact that Einstein's field equations for the so-called static vacuum configuration, $R_{mu u} = 0$, violates his Principle of Equivalence, and is therefore erroneous. This has a direct bearing on the usual concept of conservation of energy for the gravitational field and the conventional formulation for localisation of energy using Einstein's pseudo-tensor. Misconceptions as to the relationship between Minkowski spacetime and Special Relativity are also discussed, along with their relationships to the pseudo-Riemannian metric manifold of Einstein's gravitational field, and their fundamental geometric structures pertaining to spherical symmetry.

  14. Dynamics of the Bose-Einstein condensate: quasi-one-dimension and beyond

    International Nuclear Information System (INIS)

    Carr, Lincoln D.; Leung, Mary Ann; Mills College, Oakland, CA 94613-1301; Reinhardt, William P.; Department of Chemistry, University of Washington, Seattle, WA 98195-1700

    2000-01-01

    It is shown that the quasi-one-dimensional Bose-Einstein condensate is experimentally accessible and rich in intriguing phenomena. We demonstrate numerically and analytically the existence, stability and perturbation-induced dynamics of all types of stationary states of the quasi-one-dimensional nonlinear Schroedinger equation for both repulsive and attractive cases. Among our results are: the connection between stationary states and solitons; creation of vortices from such states; manipulation of such states with simple phase profiles; demonstration of the fragility of the condensate phase in response to shock; and a robust stabilization of the attractive Bose-Einstein condensate. (author)

  15. On the solution of the EPR paradox and the explanation of the violation of Bell's inequality

    OpenAIRE

    Bene, Gyula

    1997-01-01

    A new interpretation offers a consistent conceptual basis for nonrelativistic quantum mechanics. The Einstein-Podolsky-Rosen (EPR) paradox is solved and the violation of Bell's inequality is explained by maintaining realism, inductive inference and Einstein separability.

  16. Research on the Einstein-Podolsky-Rosen paradox

    International Nuclear Information System (INIS)

    Piccioni, O.; Mehlhop, W.; Wright, B.

    1989-06-01

    This report discusses the following: The analysis of the singlet state of separate fermions proves that the EPR contradicts QM. The violation of special relativity. The Schroedinger equation and the EPR. The conservation of angular momentum. The proposal of collapse. The factorization of the spin states. The superposition principle. No paradox exists within the theory. The original state of Einstein et al is not a valid example of the EPR, and it seems impossible to construct a valid linear momentum example. This is another indication that the EPR contradicts QM. Actions at a distance, the model of Einstein et al for particles with mass, and Bell's inequalities and their physical meaning

  17. High temperature breakdown of the Stokes-Einstein relation in a computer simulated Cu-Zr melt

    Energy Technology Data Exchange (ETDEWEB)

    Han, X. J., E-mail: xjhan@sjtu.edu.cn; Li, J. G., E-mail: lijg@sjtu.edu.cn [School of Materials Science and Engineering, Shanghai Jiao Tong University, Dongchuan Rd. 800, 200240 Shanghai (China); Schober, H. R., E-mail: h.schober@fz-juelich.de [Peter Grünberg Institut, Forschungszentrum Jülich, D-52425 Jülich (Germany)

    2016-03-28

    Transport properties and the Stokes-Einstein (SE) relation in liquid Cu{sub 8}Zr{sub 3} are studied by molecular dynamics simulation with a modified embedded atom potential. The critical temperature T{sub c} of mode coupling theory (MCT) is derived as 930 K from the self-diffusion coefficient D and viscosity η. The SE relation breaks down around T{sub SE} = 1900 K, which is far above T{sub c}. At temperatures below T{sub SE}, the product of D and η fluctuates around a constant value, similar to the prediction of MCT near T{sub c}. The influence of the microscopic atomic motion on macroscopic properties is investigated by analyzing the time dependent liquid structure and the self-hole filling process. The self-holes for the two components are preferentially filled by atoms of the same component. The self-hole filling dynamics explains the different breakdown behaviors of the SE relation in Zr-rich liquid CuZr{sub 2} compared to Cu-rich Cu{sub 8}Zr{sub 3}. At T{sub SE}, a kink is found in the temperature dependence of both partial and total coordination numbers for the three atomic pair combinations and of the typical time of self-hole filling. This indicates a strong correlation between liquid structure, atomic dynamics, and the breakdown of SE relation. The previously suggested usefulness of the parameter d(D{sub 1}/D{sub 2})/dT to predict T{sub SE} is confirmed. Additionally we propose a viscosity criterion to predict T{sub SE} in the absence of diffusion data.

  18. Einstein-Podolsky-Rosen-Bohm laboratory experiments : Data analysis and simulation

    NARCIS (Netherlands)

    De Raedt, H.; Michielsen, K.; Jin, F.; DAriano, M; Fei, SM; Haven, E; Hiesmayr, B; Jaeger, G; Khrennikov, A; Larsson, JA

    2012-01-01

    Data produced by laboratory Einstein-Podolsky-Rosen-Bohm (EPRB) experiments is tested against the hypothesis that the statistics of this data is given by quantum theory of this thought experiment. Statistical evidence is presented that the experimental data, while violating Bell inequalities, does

  19. Violation of the Cauchy-Schwarz inequality in collective Raman scattering

    International Nuclear Information System (INIS)

    Shumovskij, A.S.; Tran Quang

    1988-01-01

    The violation of Cauchy-Schwarz (C-S) inequality for correlations between spectrum components of the Reyleigh line and between components of the Stokes line in the collective Raman scattering is discussed. It is shown that the violation of the C-S inequailty occurs only in the Rayleigh line, moreover, for the sidebands of the Rayleigh line the violation of the C-S inequality takes place for a large number of atoms, which means that this quantum effect has the macroscopic nature. 20 refs.; 3 figs

  20. Relativistic Bose-Einstein condensates thin-shell wormholes

    Science.gov (United States)

    Richarte, M. G.; Salako, I. G.; Graça, J. P. Morais; Moradpour, H.; Övgün, Ali

    2017-10-01

    We construct traversable thin-shell wormholes which are asymptotically Ads/dS applying the cut and paste procedure for the case of an acoustic metric created by a relativistic Bose-Einstein condensate. We examine several definitions of the flare-out condition along with the violation or not of the energy conditions for such relativistic geometries. Under reasonable assumptions about the equation of state of the matter located at the shell, we concentrate on the mechanical stability of wormholes under radial perturbation preserving the original spherical symmetry. To do so, we consider linearized perturbations around static solutions. We obtain that dS acoustic wormholes remain stable under radial perturbations as long as they have small radius; such wormholes with finite radius do not violate the strong/null energy condition. Besides, we show that stable Ads wormhole satisfy some of the energy conditions whereas unstable Ads wormhole with large radii violate them.

  1. Perturbations and quasi-normal modes of black holes in Einstein-Aether theory

    International Nuclear Information System (INIS)

    Konoplya, R.A.; Zhidenko, A.

    2007-01-01

    We develop a new method for calculation of quasi-normal modes of black holes, when the effective potential, which governs black hole perturbations, is known only numerically in some region near the black hole. This method can be applied to perturbations of a wide class of numerical black hole solutions. We apply it to the black holes in the Einstein-Aether theory, a theory where general relativity is coupled to a unit time-like vector field, in order to observe local Lorentz symmetry violation. We found that in the non-reduced Einstein-Aether theory, real oscillation frequency and damping rate of quasi-normal modes are larger than those of Schwarzschild black holes in the Einstein theory

  2. Entropy bound and causality violation in higher curvature gravity

    International Nuclear Information System (INIS)

    Neupane, Ishwaree P; Dadhich, Naresh

    2009-01-01

    In any quantum theory of gravity we do expect corrections to Einstein gravity to occur. Yet, at a fundamental level, it is not apparent what the most relevant corrections are. We argue that the generic curvature square corrections present in the lower dimensional actions of various compactified string theories provide a natural passage between the classical and quantum realms of gravity. The Gauss-Bonnet and (Riemann) 2 gravities, in particular, provide concrete examples in which inconsistency of a theory, such as a violation of microcausality, and a classical limit on black hole entropy are correlated. In such theories the ratio of the shear viscosity to the entropy density, η/s, can be smaller than for a boundary conformal field theory with Einstein gravity dual. This result is interesting from the viewpoint that nuclear matter or quark-gluon plasma produced (such as at RHIC) under extreme densities and temperatures may violate the conjectured KSS bound η/s ≥ 1/4π, albeit marginally so.

  3. Regge behavior saves string theory from causality violations

    DEFF Research Database (Denmark)

    di Vecchia, Paolo; Giuseppe, D'Appollonio; Russo, Rodolfo

    2015-01-01

    Higher-derivative corrections to the Einstein-Hilbert action are present in bosonic string theory leading to the potential causality violations recently pointed out by Camanho et al. [1]. We analyze in detail this question by considering high-energy string-brane collisions at impact parameters b....... Such violations are instead neatly avoided when the full structure of string theory — and in particular its Regge behavior — is taken into account....... ≤ l s (the string-length parameter) with l s ≫ R p (the characteristic scale of the Dp-brane geometry). If we keep only the contribution of the massless states causality is violated for a set of initial states whose polarization is suitably chosen with respect to the impact parameter vector...

  4. Einstein solvmanifolds and the pre-Einstein derivation

    OpenAIRE

    Nikolayevsky, Y.

    2008-01-01

    An Einstein nilradical is a nilpotent Lie algebra, which can be the nilradical of a metric Einstein solvable Lie algebra. The classification of Riemannian Einstein solvmanifolds (possibly, of all noncompact homogeneous Einstein spaces) can be reduced to determining, which nilpotent Lie algebras are Einstein nilradicals and to finding, for every Einstein nilradical, its Einstein metric solvable extension. For every nilpotent Lie algebra, we construct an (essentially unique) derivation, the pre...

  5. Einstein-Podolsky-Rosen argument and Bell inequalities for Bose-Einstein spin condensates

    International Nuclear Information System (INIS)

    Laloee, F.; Mullin, W. J.

    2008-01-01

    We discuss the properties of two Bose-Einstein condensates in different spin states, represented quantum mechanically by a double Fock state. Individual measurements of the spins of the particles are performed in transverse directions (perpendicular to the spin quantization axis), giving access to the relative phase of the two macroscopically occupied states. Before the first spin measurement, the phase is completely undetermined; after a few measurements, a more and more precise knowledge of its value emerges under the effect of the quantum measurement process. This naturally leads to the usual notion of a quasiclassical phase (Anderson phase) and to an interesting transposition of the Einstein-Podolsky-Rosen argument to macroscopic physical quantities. The purpose of this paper is to discuss this transposition, as well as situations where the notion of a quasiclassical phase is no longer sufficient to account for the quantum results, and where significant violations of Bell-type inequalities are predicted. Quantum mechanically, the problem can be treated exactly: the probability for all sequences of results can be expressed in the form of a double integral, depending on all parameters that define the experiment (number of particles, number and angles of measurements). We discuss the differences between this case and the usual two-spin case. We discuss the effect of the many parameters that the experimenters can adjust for their measurements, starting with a discussion of the effect of the angles of measurement (the 'settings'), and then envisaging various choices of the functions that are used to obtain violation of Bell-Clauser-Horne-Shimony-Holt inequalities. We then discuss how the 'sample bias loophole' (often also called 'efficiency loophole') can be closed in this case, by introducing a preliminary sequence of measurements to localize the particles into 'measurement boxes'. We finally show that the same nonlocal effects can be observed with distinguishable

  6. Einstein-aether as a quantum effective field theory

    International Nuclear Information System (INIS)

    Withers, Benjamin

    2009-01-01

    The possibility that Lorentz symmetry is violated in gravitational processes is relatively unconstrained by experiment, in stark contrast with the level of accuracy to which Lorentz symmetry has been confirmed in the matter sector. One model of Lorentz violation in the gravitational sector is Einstein-aether theory, in which Lorentz symmetry is broken by giving a vacuum expectation value to a dynamical vector field. In this paper, we analyse the effective theory for quantized gravitational and aether perturbations. We show that this theory possesses a controlled effective expansion within dimensional regularization, that is, for any process there are a finite number of Feynman diagrams which will contribute to a given order of accuracy. We find that there is no log running of the 2-derivative phenomenological parameters, justifying the use of experimental constraints for these parameters obtained over many orders of magnitude in energy scale. Given the stringent experimental bounds on 2-derivative Lorentz-violating operators, we estimate the size of matter Lorentz violation which arises due to loop effects. This amounts to an estimation of the natural size of coefficients for Lorentz-violating dimension-6 matter operators, which in turn can be used to obtain a new bound on the 2-derivative parameters of this theory.

  7. Nonlocal Quantum Effects with Bose-Einstein Condensates

    International Nuclear Information System (INIS)

    Laloee, F.; Mullin, W. J.

    2007-01-01

    We study theoretically the properties of two Bose-Einstein condensates in different spin states, represented by a double Fock state. Individual measurements of the spins of the particles are performed in transverse directions, giving access to the relative phase of the condensates. Initially, this phase is completely undefined, and the first measurements provide random results. But a fixed value of this phase rapidly emerges under the effect of the successive quantum measurements, giving rise to a quasiclassical situation where all spins have parallel transverse orientations. If the number of measurements reaches its maximum (the number of particles), quantum effects show up again, giving rise to violations of Bell type inequalities. The violation of Bell-Clauser-Horne-Shimony-Holt inequalities with an arbitrarily large number of spins may be comparable (or even equal) to that obtained with two spins

  8. Einstein's Cosmos (German Title: Einsteins Kosmos)

    Science.gov (United States)

    Duerbeck, Hilmar W.; Dick, Wolfgang R.

    The different contributions of the present volume illuminate the interaction between Einstein and his colleagues when the foundations of modern cosmology were laid: First, the relativistic effects in the solar system, the gravitational redshift in the solar spectrum, and Einstein's relations with Freundlich and Eddington. Second, the cosmological models of Einstein, de Sitter, Friedmann, and Lemaître, which were discussed controversely till the end of the 1920s. Other scientists have also widened or critically questioned Einstein's insight and knowledge: Schwarzschild, Selety, Silberstein, and Mandl, whose life and work is discussed in separate articles. In those days, politics more than ever in history had influenced the lifes of scientists. Therefore, some comments on the ``political cosmos'' that has influenced decisively Einstein's life are also given. A special role in popularizing Einstein's world view was played by Archenhold Observatory in Berlin. A list of Einstein memorial places and a bibliographic list conclude the present book. All papers are written in German, and have English abstracts.

  9. Can we close the Bohr-Einstein quantum debate?

    Science.gov (United States)

    Kupczynski, Marian

    2017-11-13

    Recent experiments allow one to conclude that Bell-type inequalities are indeed violated; thus, it is important to understand what this means and how we can explain the existence of strong correlations between outcomes of distant measurements. Do we have to announce that Einstein was wrong, Nature is non-local and non-local correlations are produced due to quantum magic and emerge, somehow, from outside space-time? Fortunately, such conclusions are unfounded because, if supplementary parameters describing measuring instruments are correctly incorporated in a theoretical model, then Bell-type inequalities may not be proved. We construct a simple probabilistic model allowing these correlations to be explained in a locally causal way. In our model, measurement outcomes are neither predetermined nor produced in an irreducibly random way. We explain why, contrary to the general belief, the introduction of setting-dependent parameters does not restrict experimenters' freedom of choice. Since the violation of Bell-type inequalities does not allow the conclusion that Nature is non-local and that quantum theory is complete, the Bohr-Einstein quantum debate may not be closed. The continuation of this debate is important not only for a better understanding of Nature but also for various practical applications of quantum phenomena.This article is part of the themed issue 'Second quantum revolution: foundational questions'. © 2017 The Author(s).

  10. Can we close the Bohr-Einstein quantum debate?

    Science.gov (United States)

    Kupczynski, Marian

    2017-10-01

    Recent experiments allow one to conclude that Bell-type inequalities are indeed violated; thus, it is important to understand what this means and how we can explain the existence of strong correlations between outcomes of distant measurements. Do we have to announce that Einstein was wrong, Nature is non-local and non-local correlations are produced due to quantum magic and emerge, somehow, from outside space-time? Fortunately, such conclusions are unfounded because, if supplementary parameters describing measuring instruments are correctly incorporated in a theoretical model, then Bell-type inequalities may not be proved. We construct a simple probabilistic model allowing these correlations to be explained in a locally causal way. In our model, measurement outcomes are neither predetermined nor produced in an irreducibly random way. We explain why, contrary to the general belief, the introduction of setting-dependent parameters does not restrict experimenters' freedom of choice. Since the violation of Bell-type inequalities does not allow the conclusion that Nature is non-local and that quantum theory is complete, the Bohr-Einstein quantum debate may not be closed. The continuation of this debate is important not only for a better understanding of Nature but also for various practical applications of quantum phenomena. This article is part of the themed issue `Second quantum revolution: foundational questions'.

  11. Einstein-Podolsky-Rosen Entanglement of Narrowband Photons from Cold Atoms

    OpenAIRE

    Lee, Jong-Chan; Park, Kwang-Kyoon; Zhao, Tian-Ming; Kim, Yoon-Ho

    2016-01-01

    Einstein-Podolsky-Rosen (EPR) entanglement introduced in 1935 deals with two particles that are entangled in their positions and momenta. Here we report the first experimental demonstration of EPR position-momentum entanglement of narrowband photon pairs generated from cold atoms. By using two-photon quantum ghost imaging and ghost interference, we demonstrate explicitly that the narrowband photon pairs violate the separability criterion, confirming EPR entanglement. We further demonstrate co...

  12. Test of Einstein-Podolsky-Rosen steering based on the all-versus-nothing proof.

    Science.gov (United States)

    Wu, Chunfeng; Chen, Jing-Ling; Ye, Xiang-Jun; Su, Hong-Yi; Deng, Dong-Ling; Wang, Zhenghan; Oh, C H

    2014-03-06

    In comparison with entanglement and Bell nonlocality, Einstein-Podolsky-Rosen steering is a newly emerged research topic and in its incipient stage. Although Einstein-Podolsky-Rosen steering has been explored via violations of steering inequalities both theoretically and experimentally, the known inequalities in the literatures are far from well-developed. As a result, it is not yet possible to observe Einstein-Podolsky-Rosen steering for some steerable mixed states. Recently, a simple approach was presented to identify Einstein-Podolsky-Rosen steering based on all-versus-nothing argument, offering a strong condition to witness the steerability of a family of two-qubit (pure or mixed) entangled states. In this work, we show that the all-versus-nothing proof of Einstein-Podolsky-Rosen steering can be tested by measuring the projective probabilities. Through the bound of probabilities imposed by local-hidden-state model, the proposed test shows that steering can be detected by the all-versus-nothing argument experimentally even in the presence of imprecision and errors. Our test can be implemented in many physical systems and we discuss the possible realizations of our scheme with non-Abelian anyons and trapped ions.

  13. Fragile Thermodynamic Order

    International Nuclear Information System (INIS)

    Bernhoeft, N.; Lander, G.H.; Colineau, E.

    2003-01-01

    An asymmetric shift in the position of the magnetic Bragg peak with respect to the fiducial lattice has been observed by resonant X-ray scattering in a diverse series of antiferromagnetic compounds. This apparent violation of Bragg's law is interpreted in terms of a dynamically phased order parameter. We demonstrate the use of this effect as a novel probe of fragile or dynamic thermodynamic order in strongly correlated electronic systems. In particular, fresh light is shed on the paradoxical situation encountered in URu 2 Si 2 where the measured entropy gain on passing through T Neel is incompatible with the ground state moment estimated by neutron diffraction. The intrinsic space-time averaging of the probe used to characterise the thermodynamic macroscopic state may play a crucial and previously neglected role. In turn, this suggests the further use of resonant X-ray scattering in investigations of systems dominated by quantum fluctuations. (author)

  14. Black holes in Lorentz-violating gravity theories

    International Nuclear Information System (INIS)

    Barausse, Enrico; Sotiriou, Thomas P

    2013-01-01

    Lorentz symmetry and the notion of light cones play a central role in the definition of horizons and the existence of black holes. Current observations provide strong indications that astrophysical black holes do exist in Nature. Here we explore what happens to the notion of a black hole in gravity theories where local Lorentz symmetry is violated, and discuss the relevant astrophysical implications. Einstein-aether theory and Hořava gravity are used as the theoretical background for addressing this question. We review earlier results about static, spherically symmetric black holes, which demonstrate that in Lorentz-violating theories there can be a new type of horizon and, hence, a new notion of black hole. We also present both known and new results on slowly rotating black holes in these theories, which provide insights on how generic these new horizons are. Finally, we discuss the differences between black holes in Lorentz-violating theories and in General Relativity, and assess to what extent they can be probed with present and future observations. (paper)

  15. Horndeski gravity and the violation of reverse isoperimetric inequality

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Xing-Hui; Lu, Wen-Tian; Lue, H. [Beijing Normal University, Department of Physics, Center for Advanced Quantum Studies, Beijing (China); Liu, Hai-Shan [Zhejiang University of Technology, Institute for Advanced Physics and Mathematics, Hangzhou (China)

    2017-11-15

    We consider Einstein-Horndeski-Maxwell gravity, together with a cosmological constant and multiple Horndeski axions. We construct charged AdS planar black holes in general dimensions where the Horndeski axions span over the planar directions. We analyze the thermodynamics and obtain the black hole volumes. We show that the reverse isoperimetric inequality can be violated, implying that these black holes can store information more efficiently than the Schwarzschild black hole. (orig.)

  16. Einstein today; Einstein aujourd'hui

    Energy Technology Data Exchange (ETDEWEB)

    Aspect, A.; Grangier, Ph. [Centre National de la Recherche Scientifique (CNRS), Lab. Charles Fabry de l' Institut d' Optique a Orsay, 91 - Orsay (France); Bouchet, F.R. [Institut d' Astrophysique de Paris, CNRS, 75 - Paris (France); Brunet, E.; Derrida, B. [Universite Pierre et Marie Curie, Ecole Normale Superieure, 75 - Paris (France); Cohen-Tannoudji, C. [Academie des Sciences, 75 - Paris (France); Dalibard, J.; Laloe, F. [Laboratoire Kastler Brossel. UMR 8552 (ENS, UPMC, CNRS), 75 - Paris (France); Damour, Th. [Institut des Hautes Etudes Scientifiques, 91 - Bures sur Yvette (France); Darrigol, O. [Centre National de la Recherche Scientifique (CNRS), Groupe Histoire des Sciences Rehseis, 75 - Paris (France); Pocholle, J.P. [Thales Research et Technology France, 91 - Palaiseau (France)

    2005-07-01

    The most important contributions of Einstein involve 5 fields of physics : the existence of quanta (light quanta, stimulated radiation emission and Bose-Einstein condensation), relativity, fluctuations (Brownian motion and thermodynamical fluctuations), the basis of quantum physics and cosmology (cosmological constant and the expansion of the universe). Diverse and renowned physicists have appreciated the development of modern physics from Einstein's ideas to the knowledge of today. This book is a collective book that gathers their work under 7 chapters: 1) 1905, a new beginning; 2) from the Einstein, Podolsky and Rosen's article to quantum information (cryptography and quantum computers); 3) the Bose-Einstein condensation in gases; 4) from stimulated emission to the today's lasers; 5) Brownian motion and the fluctuation-dissipation theory; 6) general relativity; and 7) cosmology. (A.C.)

  17. Rotation driven translational diffusion of polyatomic ions in water: A novel mechanism for breakdown of Stokes-Einstein relation

    Science.gov (United States)

    Banerjee, Puja; Yashonath, Subramanian; Bagchi, Biman

    2017-04-01

    While most of the existing theoretical and simulation studies have focused on simple, spherical, halide and alkali ions, many chemically, biologically, and industrially relevant electrolytes involve complex non-spherical polyatomic ions like nitrate, chlorate, and sulfate to name only a few. Interestingly, some polyatomic ions in spite of being larger in size show anomalously high diffusivity and therefore cause a breakdown of the venerable Stokes-Einstein (S-E) relation between the size and diffusivity. Here we report a detailed analysis of the dynamics of anions in aqueous potassium nitrate (KNO3) and aqueous potassium acetate (CH3COOK) solutions. The two ions, nitrate (-NO3) and acetate (CH3-CO2 ), with their similar size show a large difference in diffusivity values. We present evidence that the translational motion of these polyatomic ions is coupled to the rotational motion of the ion. We show that unlike the acetate ion, nitrate ion with a symmetric charge distribution among all periphery oxygen atoms shows a faster rotational motion with large amplitude rotational jumps which enhances its translational motion due to translational-rotational coupling. By creating a family of modified-charge model systems, we have analysed the rotational motion of asymmetric polyatomic ions and the contribution of it to the translational motion. These model systems help clarifying and establishing the relative contribution of rotational motion in enhancing the diffusivity of the nitrate ion over the value predicted by the S-E relation and also over the other polyatomic ions having asymmetric charge distribution like the acetate ion. In the latter case, reduced rotational motion results in lower diffusivity values than those with symmetric charge distribution. We propose translational-rotational coupling as a general mechanism of the breakdown of the S-E relation in the case of polyatomic ions.

  18. Einstein-Podolsky-Rosen correlation in a gravitational field

    International Nuclear Information System (INIS)

    Terashima, Hiroaki; Ueda, Masahito

    2004-01-01

    For quantum communication in a gravitational field, the properties of the Einstein-Podolsky-Rosen (EPR) correlation are studied within the framework of general relativity. Acceleration and gravity are shown to deteriorate the perfect anticorrelation of an EPR pair of spins in the same direction, and apparently decrease the degree of the violation of Bell's inequality. To maintain the perfect EPR correlation and the maximal violation of Bell's inequality, observers must measure the spins in appropriately chosen different directions which depend on the velocity of the particles, the curvature of the space-time, and the positions of the observers. Near the event horizon of a black hole, the appropriate directions depend so sensitively on the positions of the observers that even a very small uncertainty in the identification of the observers' positions leads to a fatal error in quantum communication, unless the observers fall into the black hole together with the particles

  19. Einstein and Austria

    International Nuclear Information System (INIS)

    Broda, E.

    1979-01-01

    This text was written by Engelbert Broda in 1979 and is about Albert Einstein and his relation to Austria. This text is split in different sections which are amongst others: Einstein und Mach; Einstein und Boltzmann; Positivism, Atoms and Relativity; Einstein as an Austrian professor; Einstein’s visits to Austria; Einstein and Viennese friends; Einstein and Friedrich Adler; Einstein and the Austrian mentality; (nowak)

  20. On a new approach for constructing wormholes in Einstein-Born-Infeld gravity

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Young [Kunsan National University, Department of Physics, Kunsan (Korea, Republic of); Park, Mu-In [Sogang University, Research Institute for Basic Science, Seoul (Korea, Republic of)

    2016-11-15

    We study a new approach for the wormhole construction in Einstein-Born-Infeld gravity, which does not require exotic matters in the Einstein equation. The Born-Infeld field equation is not modified by coordinate independent conditions of continuous metric tensor and its derivatives, even though the Born-Infeld fields have discontinuities in their derivatives at the throat in general. We study the relation of the newly introduced conditions with the usual continuity equation for the energy-momentum tensor and the gravitational Bianchi identity. We find that there is no violation of energy conditions for the Born-Infeld fields contrary to the usual approaches. The exoticity of the energy-momentum tensor is not essential for sustaining wormholes. Some open problems are discussed. (orig.)

  1. Inseparability criteria for demonstration of the Einstein-Podolsky-Rosen gedanken experiment

    OpenAIRE

    Reid, M. D.

    2001-01-01

    It is shown that a criterion used to demonstrate realization of the 1935 Einstein-Podolsky-Rosen (EPR) gedanken experiment is sufficient to demonstrate quantum entanglement. A further set of measurable criteria sufficient to demonstrate EPR gedanken experiment is proposed, these being the set of criteria sufficient to demonstrate entanglement, by way of a measured violation of a necessary condition of separability. In this way, provided the spatial separation of systems is sufficient to ensur...

  2. Dark Energy from Violation of Energy Conservation.

    Science.gov (United States)

    Josset, Thibaut; Perez, Alejandro; Sudarsky, Daniel

    2017-01-13

    In this Letter, we consider the possibility of reconciling metric theories of gravitation with a violation of the conservation of energy-momentum. Under some circumstances, this can be achieved in the context of unimodular gravity, and it leads to the emergence of an effective cosmological constant in Einstein's equation. We specifically investigate two potential sources of energy nonconservation-nonunitary modifications of quantum mechanics and phenomenological models motivated by quantum gravity theories with spacetime discreteness at the Planck scale-and show that such locally negligible phenomena can nevertheless become relevant at the cosmological scale.

  3. Homogenization of Stokes and Navier-Stokes equations

    International Nuclear Information System (INIS)

    Allaire, G.

    1990-04-01

    This thesis is devoted to homogenization of Stokes and Navier-Stokes equations with a Dirichlet boundary condition in a domain containing many tiny obstacles. Tipycally those obstacles are distributed at the modes of a periodic lattice with same small period in each axe's direction, and their size is always asymptotically smaller than the lattice's step. With the help of the energy method, and thanks to a suitable pressure's extension, we prove the convergence of the homogenization process when the lattice's step tends to zero (and thus the number of obstacles tends to infinity). For a so-called critical size of the obstacles, the homogenized problem turns out to be a Brinkman's law (i.e. Stokes or Navier-Stokes equation plus a linear zero-order term for the velocity in the momentum equation). For obstacles which have a size smaller than the critical one, the limit problem reduces to the initial Stokes or Navier-Stokes equations, while for larger sizes the homogenized problem a Darcy's law. Furthermore, those results have been extended to the case of obstacles included in a hyperplane, and we establish a simple model of fluid flows through grids, which is based on a special form of Brinkman's law [fr

  4. Generalized absorber theory and the Einstein-Podolsky-Rosen paradox

    International Nuclear Information System (INIS)

    Cramer, J.G.

    1980-01-01

    A generalized form of Wheeler-Feynman absorber theory is used to explain the quantum-mechanical paradox proposed by Einstein, Podolsky, and Rosen (EPR). The advanced solutions of the electromagnetic wave equation and of relativistic quantum-mechanical wave equations are shown to play the role of ''verifier'' in quantum-mechanical ''transactions,'' providing microscopic communication paths between detectors across spacelike intervals in violation of the EPR locality postulate. The principle of causality is discussed in the context of this approach, and possibilities for experimental tests of the theory are examined

  5. Violation of Continuous-Variable Einstein-Podolsky-Rosen Steering with Discrete Measurements

    Science.gov (United States)

    Schneeloch, James; Dixon, P. Ben; Howland, Gregory A.; Broadbent, Curtis J.; Howell, John C.

    2013-03-01

    In this Letter, we derive an entropic Einstein-Podolsky-Rosen (EPR) steering inequality for continuous-variable systems using only experimentally measured discrete probability distributions and details of the measurement apparatus. We use this inequality to witness EPR steering between the positions and momenta of photon pairs generated in spontaneous parametric down-conversion. We examine the asymmetry between parties in this inequality, and show that this asymmetry can be used to reduce the technical requirements of experimental setups intended to demonstrate the EPR paradox. Furthermore, we develop a more stringent steering inequality that is symmetric between parties, and use it to show that the down-converted photon pairs also exhibit symmetric EPR steering.

  6. Fragile X syndrome and fragile X-associated tremor ataxia syndrome.

    Science.gov (United States)

    Hall, Deborah A; Berry-Kravis, Elizabeth

    2018-01-01

    Fragile X-associated disorders encompass several conditions, which are caused by expansion mutations in the fragile X mental retardation 1 (FMR1) gene. Fragile X syndrome is the most common inherited etiology of intellectual disability and results from a full mutation or >200 CGG repeats in FMR1. It is associated with developmental delay, autism spectrum disorder, and seizures. Fragile X-associated tremor/ataxia syndrome is a progressive neurodegenerative disease that occurs in premutation carriers of 55-200 CGG repeats in FMR1 and is characterized by kinetic tremor, gait ataxia, parkinsonism, executive dysfunction, and neuropathy. Fragile X-associated primary ovarian insufficiency also occurs in premutation carrier women and manifests with infertility and early menopause. The diseases constituting fragile X-associated disorders differ mechanistically, due to the distinct molecular properties of premutation versus full mutations. Fragile X syndrome occurs when there is a lack of fragile X mental retardation protein (FMRP) due to FMR1 methylation and silencing. In fragile X-associated tremor ataxia syndrome, a toxic gain of function is postulated with the production of excess CGG repeat-containing FMR1 mRNA, abnormal translation of the repeat sequence leading to production of polyglycine, polyalanine, and other polypeptides and to outright deficits in translation leading to reduced FMRP at larger premutation sizes. The changes in underlying brain chemistry due to FMR1 mutations have led to therapeutic studies in these disorders, with some progress being made in fragile X syndrome. This paper also summarizes indications for testing, genetic counseling issues, and what the future holds for these disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. The Einstein dossiers science and politics - Einstein's Berlin period with an appendix on Einstein's FBI file

    CERN Document Server

    Grundmann, Siegfried

    2004-01-01

    In 1919 the Prussian Ministry of Science, Arts and Culture opened a dossier on "Einstein's Theory of Relativity." It was rediscovered by the author in 1961 and is used in conjunction with numerous other subsequently identified 'Einstein' files as the basis of this fascinating book. In particular, the author carefully scrutinizes Einstein's FBI file from 1950-55 against mostly unpublished material from European including Soviet sources and presents hitherto unknown documentation on Einstein's alleged contacts with the German Communist Party and the Comintern. Siegfried Grundmann's thorough study of Einstein's participation on a committee of the League of Nations, based on archival research in Geneva, is also new. This book outlines Einstein's image in politics and German science policy. It covers the period from his appointment as a researcher in Berlin to his fight abroad against the "boycott of German science" after World War I and his struggle at home against attacks on "Jewish physics" of which he was made...

  8. Equipment fragility testing

    International Nuclear Information System (INIS)

    Holman, G.S.; Chou, C.K.; Cummings, G.E.

    1985-01-01

    Current probabilistic risk assessment (PRA) methods for nuclear power plants utilize component fragilities which are for the most part based on a limited data base and engineering judgement. The seismic design of components is based on code limits and NRC requirements that do not reflect the actual capacity of a component to resist failure. In order to improve the present component fragility data base and establish component seismic design margins, the NRC has commissioned a projected three-year program to compile existing fragilities data and at the same time independently perform fragilities tests on selected mechanical and electrical components. This paper presents the planning and technical approach being taken by LLNL in the NRC Component Fragility Program

  9. Einstein today

    International Nuclear Information System (INIS)

    Aspect, A.; Grangier, Ph.; Bouchet, F.R.; Brunet, E.; Derrida, B.; Cohen-Tannoudji, C.; Dalibard, J.; Laloe, F.; Damour, Th.; Darrigol, O.; Pocholle, J.P.

    2005-01-01

    The most important contributions of Einstein involve 5 fields of physics : the existence of quanta (light quanta, stimulated radiation emission and Bose-Einstein condensation), relativity, fluctuations (Brownian motion and thermodynamical fluctuations), the basis of quantum physics and cosmology (cosmological constant and the expansion of the universe). Diverse and renowned physicists have appreciated the development of modern physics from Einstein's ideas to the knowledge of today. This book is a collective book that gathers their work under 7 chapters: 1) 1905, a new beginning; 2) from the Einstein, Podolsky and Rosen's article to quantum information (cryptography and quantum computers); 3) the Bose-Einstein condensation in gases; 4) from stimulated emission to the today's lasers; 5) Brownian motion and the fluctuation-dissipation theory; 6) general relativity; and 7) cosmology. (A.C.)

  10. Stokes drift

    Science.gov (United States)

    van den Bremer, T. S.; Breivik, Ø.

    2017-12-01

    During its periodic motion, a particle floating at the free surface of a water wave experiences a net drift velocity in the direction of wave propagation, known as the Stokes drift (Stokes 1847 Trans. Camb. Philos. Soc. 8, 441-455). More generally, the Stokes drift velocity is the difference between the average Lagrangian flow velocity of a fluid parcel and the average Eulerian flow velocity of the fluid. This paper reviews progress in fundamental and applied research on the induced mean flow associated with surface gravity waves since the first description of the Stokes drift, now 170 years ago. After briefly reviewing the fundamental physical processes, most of which have been established for decades, the review addresses progress in laboratory and field observations of the Stokes drift. Despite more than a century of experimental studies, laboratory studies of the mean circulation set up by waves in a laboratory flume remain somewhat contentious. In the field, rapid advances are expected due to increasingly small and cheap sensors and transmitters, making widespread use of small surface-following drifters possible. We also discuss remote sensing of the Stokes drift from high-frequency radar. Finally, the paper discusses the three main areas of application of the Stokes drift: in the coastal zone, in Eulerian models of the upper ocean layer and in the modelling of tracer transport, such as oil and plastic pollution. Future climate models will probably involve full coupling of ocean and atmosphere systems, in which the wave model provides consistent forcing on the ocean surface boundary layer. Together with the advent of new space-borne instruments that can measure surface Stokes drift, such models hold the promise of quantifying the impact of wave effects on the global atmosphere-ocean system and hopefully contribute to improved climate projections. This article is part of the theme issue 'Nonlinear water waves'.

  11. Properties of atomic pairs produced in the collision of Bose-Einstein condensates

    Science.gov (United States)

    Ziń, Paweł; Wasak, Tomasz

    2018-04-01

    During a collision of Bose-Einstein condensates correlated pairs of atoms are emitted. The scattered massive particles, in analogy to photon pairs in quantum optics, might be used in the violation of Bell's inequalities, demonstration of Einstein-Podolsky-Rosen correlations, or sub-shot-noise atomic interferometry. Usually, a theoretical description of the collision relies either on stochastic numerical methods or on analytical treatments involving various approximations. Here, we investigate elastic scattering of atoms from colliding elongated Bose-Einstein condensates within the Bogoliubov method, carefully controlling performed approximations at every stage of the analysis. We derive expressions for the one- and two-particle correlation functions. The obtained formulas, which relate the correlation functions to the condensate wave function, are convenient for numerical calculations. We employ the variational approach for condensate wave functions to obtain analytical expressions for the correlation functions, whose properties we analyze in detail. We also present a useful semiclassical model of the process and compare its results with the quantum one. The results are relevant for recent experiments with excited helium atoms, as well as for planned experiments aimed at investigating the nonclassicality of the system.

  12. Deriving Einstein-Podolsky-Rosen steering inequalities from the few-body Abner Shimony inequalities

    Science.gov (United States)

    Zhou, Jie; Meng, Hui-Xian; Jiang, Shu-Han; Xu, Zhen-Peng; Ren, Changliang; Su, Hong-Yi; Chen, Jing-Ling

    2018-04-01

    For the Abner Shimony (AS) inequalities, the simplest unified forms of directions attaining the maximum quantum violation are investigated. Based on these directions, a family of Einstein-Podolsky-Rosen (EPR) steering inequalities is derived from the AS inequalities in a systematic manner. For these inequalities, the local hidden state (LHS) bounds are strictly less than the local hidden variable (LHV) bounds. This means that the EPR steering is a form of quantum nonlocality strictly weaker than Bell nonlocality.

  13. Einstein was right!

    CERN Document Server

    Hess, Karl

    2014-01-01

    All modern books on Einstein emphasize the genius of his relativity theory and the corresponding corrections and extensions of the ancient space-time concept. However, Einstein's opposition to the use of probability in the laws of nature and particularly in the laws of quantum mechanics is criticized and often portrayed as outdated. The author of Einstein Was Right! takes a unique view and shows that Einstein created a ""Trojan horse"" ready to unleash forces against the use of probability as a basis for the laws of nature. Einstein warned that the use of probability would, in the final analys

  14. Maja Winteler-Einstein

    Indian Academy of Sciences (India)

    Einstein. Articles written in Resonance – Journal of Science Education. Volume 5 Issue 4 April 2000 pp 111-120 Reflections. Albert Einstein: A Biographical Sketch · Maja Winteler-Einstein · More Details Fulltext PDF ...

  15. Navier-Stokes

    NARCIS (Netherlands)

    Koren, B.

    2013-01-01

    De Navier-Stokes-vergelijkingen behoren tot de meest gebruikte vergelijkingen voor de berekening van gas- en vloeistofstromingen. Op de Vakantiecursus 2013 van het Platform Wiskunde Nederland vertelt Barry Koren over de Navier-Stokes-vergelijkingen, over stromingsleer en over openstaande

  16. NEC violation in mimetic cosmology revisited

    Directory of Open Access Journals (Sweden)

    Anna Ijjas

    2016-09-01

    Full Text Available In the context of Einstein gravity, if the null energy condition (NEC is satisfied, the energy density in expanding space–times always decreases while in contracting space–times the energy density grows and the universe eventually collapses into a singularity. In particular, no non-singular bounce is possible. It is, though, an open question if this energy condition can be violated in a controlled way, i.e., without introducing pathologies, such as unstable negative-energy states or an imaginary speed of sound. In this letter, we will re-examine the claim that the recently proposed mimetic scenario can violate the NEC without pathologies. We show that mimetic cosmology is prone to gradient instabilities even in cases when the NEC is satisfied (except for trivial examples. Most interestingly, the source of the instability is always the Einstein–Hilbert term in the action. The matter stress-energy component does not contribute spatial gradient terms but instead makes the problematic curvature modes dynamical. We also show that mimetic cosmology can be understood as a singular limit of known, well-behaved theories involving higher-derivative kinetic terms and discuss ways of removing the instability.

  17. Towards an Einstein-Podolsky-Rosen paradox between two macroscopic atomic ensembles at room temperature

    OpenAIRE

    He, Q Y; Reid, M D

    2013-01-01

    Experiments have reported the entanglement of two spatially separated macroscopic atomic ensembles at room temperature (Krauter et al 2011 Phys. Rev. Lett. 107 080503; Julsgaard et al 2001 Nature 413 400). We show how an Einstein-Podolsky-Rosen (EPR) paradox is realizable with this experiment. Our proposed test involves violation of an inferred Heisenberg uncertainty principle, which is a sufficient condition for an EPR paradox. This is a stronger test of nonlocality than entanglement. Our pr...

  18. Einstein and Prague

    International Nuclear Information System (INIS)

    Bicak, J.

    1979-01-01

    A commemorative publication is submitted issued on the occasion of Albert Einstein's centenary remembering Einstein's sojourn and work in Prague. In addition to the article Ueber den Einfluss der Schwerkraft auf die Ausbreitung des Lichtes the publications contains the author's preface to the Czech edition of his Theory, the list of studies written by Einstein while in Prague, an assay on the great physicist's life and work, and extracts from the memoires of Philipp Frank published under the title Einstein, His Life and Times. (L.O.)

  19. Revealing Hidden Einstein-Podolsky-Rosen Nonlocality

    Science.gov (United States)

    Walborn, S. P.; Salles, A.; Gomes, R. M.; Toscano, F.; Souto Ribeiro, P. H.

    2011-04-01

    Steering is a form of quantum nonlocality that is intimately related to the famous Einstein-Podolsky-Rosen (EPR) paradox that ignited the ongoing discussion of quantum correlations. Within the hierarchy of nonlocal correlations appearing in nature, EPR steering occupies an intermediate position between Bell nonlocality and entanglement. In continuous variable systems, EPR steering correlations have been observed by violation of Reid’s EPR inequality, which is based on inferred variances of complementary observables. Here we propose and experimentally test a new criterion based on entropy functions, and show that it is more powerful than the variance inequality for identifying EPR steering. Using the entropic criterion our experimental results show EPR steering, while the variance criterion does not. Our results open up the possibility of observing this type of nonlocality in a wider variety of quantum states.

  20. Einstein and Planck

    Science.gov (United States)

    Heilbron, John

    2005-03-01

    As an editor of the Annalen der Physik, Max Planck published Einstein's early papers on thermodynamics and on special relativity, which Planck probably was the first major physicist to appreciate. They respected one another not only as physicists but also, for their inspired creation of world pictures, as artists. Planck helped to establish Einstein in a sinecure at the center of German physics, Berlin. Despite their differences in scientific style, social life, politics, and religion, they became fast friends. Their mutual admiration survived World War I, during which Einstein advocated pacifism and Planck signed the infamous Manifesto of the 93 Intellectuals supporting the German invasion of Belgium. It also survived the Weimar Republic, which Einstein favored and Planck disliked. Physics drew them together, as both opposed the Copenhagen Interpretation; so did common decency, as Planck helped to protect Einstein from anti-semitic attacks. Their friendship did not survive the Nazis. As a standing secretary of the Berlin Academy, Planck had to advise Einstein to resign from it before his colleagues, outraged at his criticism of the new Germany from the safety of California, expelled him. Einstein never forgave his old friend and former fellow artist for not protesting publicly against his expulsion and denigration, and other enormities of National Socialism. .

  1. Einsteins dream

    International Nuclear Information System (INIS)

    Parker, B.

    1986-01-01

    This book discusses the following topics: the search for meaning; Einstein's dream; curved space; Einstein and warped space-time and extreme wraping; early unified field theories; star death; beyond the white dwarf; the early universe; the hadron, Lepton, and Radiation eras; the redshift controversy; other universes; the final fate of the universe; the missing mass; bounce; fate of the open universe; the world of particles and fields; Dirac's equation; Yukawa; gauge theory; quantum chromodynamics; supergravity and superstrings; twistors and heaven; and the new Einstein

  2. The Chevreton tensor and Einstein-Maxwell spacetimes conformal to Einstein spaces

    International Nuclear Information System (INIS)

    Bergqvist, Goeran; Eriksson, Ingemar

    2007-01-01

    In this paper, we characterize the source-free Einstein-Maxwell spacetimes which have a trace-free Chevreton tensor. We show that this is equivalent to the Chevreton tensor being of pure radiation type and that it restricts the spacetimes to Petrov type N or O. We prove that the trace of the Chevreton tensor is related to the Bach tensor and use this to find all Einstein-Maxwell spacetimes with a zero cosmological constant that have a vanishing Bach tensor. Among these spacetimes we then look for those which are conformal to Einstein spaces. We find that the electromagnetic field and the Weyl tensor must be aligned, and in the case that the electromagnetic field is null, the spacetime must be conformally Ricci-flat and all such solutions are known. In the non-null case, since the general solution is not known on a closed form, we settle by giving the integrability conditions in the general case, but we do give new explicit examples of Einstein-Maxwell spacetimes that are conformal to Einstein spaces, and we also find examples where the vanishing of the Bach tensor does not imply that the spacetime is conformal to a C-space. The non-aligned Einstein-Maxwell spacetimes with vanishing Bach tensor are conformally C-spaces, but none of them are conformal to Einstein spaces

  3. Einstein's meanders

    Science.gov (United States)

    Lomnitz, C.

    2007-05-01

    What does Einstein have to do with subduction? Good question. Peaceful Lake Budi, lying at the heart of an Indian reservation in the Deep South of Chile, had subsided by two meters in the 1960 mega-thrust earthquake. This unique South American salt lake was hiding an awful secret: it was actually an oxbow, not a lake. But Einstein had realized in 1926 that meanders are natural freaks. Rivers will not flow uphill, yet - he claimed - they don't flow down the path of steepest descent either. This anomaly was put at the doorstep of a weak Coriolis Force. Thus Einstein problematized the dilemma of the earth sciences. How can a non-force produce margin-parallel compression in a convergent margin where extension is expected? In fact, where does the energy for meander formation come from? Good question . . . Even Wikipedia knows that Coriolis is not a “force” but an “effect”. So is the obliquity of plate convergence in subduction. Where did Einstein err, and where was he a pioneer? Coastal ablation plus alternating subsidence and emergence in giant earthquakes may yield an answer. Einstein, A. (1926). Die Ursache der Maeanderbildung der Flusslaeufe und das sogenannte Baersche Gesetz, Naturwissenschaften, 14, fascicle II.

  4. From Einstein-Podolsky-Rosen paradox to quantum nonlocality: experimental investigation of quantum correlations

    Science.gov (United States)

    Xu, Jin-Shi; Li, Chuan-Feng; Guo, Guang-Can

    2016-11-01

    In 1935, Einstein, Podolsky and Rosen published their influential paper proposing a now famous paradox (the EPR paradox) that threw doubt on the completeness of quantum mechanics. Two fundamental concepts: entanglement and steering, were given in the response to the EPR paper by Schrodinger, which both reflect the nonlocal nature of quantum mechanics. In 1964, John Bell obtained an experimentally testable inequality, in which its violation contradicts the prediction of local hidden variable models and agrees with that of quantum mechanics. Since then, great efforts have been made to experimentally investigate the nonlocal feature of quantum mechanics and many distinguished quantum properties were observed. In this work, along with the discussion of the development of quantum nonlocality, we would focus on our recent experimental efforts in investigating quantum correlations and their applications with optical systems, including the study of entanglement-assisted entropic uncertainty principle, Einstein-Podolsky-Rosen steering and the dynamics of quantum correlations.

  5. Celebrating Einstein

    Science.gov (United States)

    Shapiro Key, Joey; Yunes, Nicolas

    2013-04-01

    The Gravity Group at Montana State University (MSU) hosted Celebrating Einstein, a free public arts and multimedia event celebrating Einstein and his ideas in Bozeman, Montana April 2-6, 2013. The products of our efforts are now available to any party interested in hosting a similar event. Celebrating Einstein is a truly interdisciplinary effort including art, film, dance, music, physics, history, and education. Events included a black hole immersive art installation, a series of public talks by physicists, and Einstein lessons in the public schools leading up to a live free public multimedia performance including a professional dance company, a live interview with a renowned physicist, and an original score composed for the MSU student symphony to be performed with an original film produced by the Science and Natural History film program at MSU. This project is funded by the Montana Space Grant Consortium, Montana State University, and the National Science Foundation.

  6. Violation of a Bell-like inequality in single-neutron interferometry.

    Science.gov (United States)

    Hasegawa, Yuji; Loidl, Rudolf; Badurek, Gerald; Baron, Matthias; Rauch, Helmut

    2003-09-04

    Non-local correlations between spatially separated systems have been extensively discussed in the context of the Einstein, Podolsky and Rosen (EPR) paradox and Bell's inequalities. Many proposals and experiments designed to test hidden variable theories and the violation of Bell's inequalities have been reported; usually, these involve correlated photons, although recently an experiment was performed with (9)Be(+) ions. Nevertheless, it is of considerable interest to show that such correlations (arising from quantum mechanical entanglement) are not simply a peculiarity of photons. Here we measure correlations between two degrees of freedom (comprising spatial and spin components) of single neutrons; this removes the need for a source of entangled neutron pairs, which would present a considerable technical challenge. A Bell-like inequality is introduced to clarify the correlations that can arise between observables of otherwise independent degrees of freedom. We demonstrate the violation of this Bell-like inequality: our measured value is 2.051 +/- 0.019, clearly above the value of 2 predicted by classical hidden variable theories.

  7. The Einstein almanac

    CERN Document Server

    Calaprice, Alice

    2005-01-01

    Albert Einstein was an exceptional human being. Perhaps nothing reflects the breadth and scope of his brilliance, his interests, and his influence better than his publications -- more than six hundred scientific papers, books, essays, reviews, and opinion pieces. Einstein began publishing in March 1901 with a scientific work that appeared in the German journal Annalen der Physik when he was twenty-two; the last publication was an editorial in the journal Common Cause which appeared a few months before his death in 1955. In the fifty-four-year interval, his published work ranged widely over relativity theory and quantum physics, nationalism, Judaism, war, peace, and education. Indeed, Einstein's literary output was so abundant that even many of his most informed admirers are not familiar with all of it. The Einstein Almanac takes a look at Einstein's year-by-year output, explaining his three-hundred most important publications and setting them into the context of his life, science, and world history. Concentr...

  8. Einstein and relativity

    International Nuclear Information System (INIS)

    Cullwick, E.G.

    1979-01-01

    Einstein published his Special Theory of Relativity in 1905 and in 1915 his General Theory which predicted the bending of light rays passing near the sun. This prediction was apparently confirmed experimentally in 1919 bringing Einstein popular acclaim. Einstein's work is reviewed and the question of whether he was in fact first in the field is examined with especial reference to the work of Maxwell, Lorentz and Poincare. (U.K.)

  9. Einstein the searcher his work explained from dialogues with Einstein

    CERN Document Server

    Moszkowski, Alexander

    2014-01-01

    This volume, first published in 1921, presents a series of portraits of Einstein, thus offering glimpses in the character and private reflections of the man who changed the course of modern science. Intended neither as a biography, nor as a résumé of Einsteinian physics, Einstein: The Searcher instead focusses on Einstein's relationship with the scientific project as he himself conceived it, and so is still of contemporary significance for those puzzled by the spirit of scientific enquiry.

  10. From Einstein to AXAF

    International Nuclear Information System (INIS)

    Tananbaum, H.

    1990-01-01

    The presentations at the 10th Anniversary Einstein Symposium and the articles in this book cover a wide variety of scientific topics describing some of the important advances and discoveries made with the Einstein Observatory. The breadth and depth of science carried out with Einstein has made it essentially impossible to cover fully individual subdisciplines in single review talks and papers. Some of the major Einstein highlights are summarized and the scientific prospects for AXAF are assessed. (author)

  11. Einstein. A centenary volume

    International Nuclear Information System (INIS)

    French, A.P.

    1979-01-01

    The subject is divided as follows: part 1, reminiscences (of Einstein and his life, by various authors); part 2, Einstein and his work (includes accounts of special and general relativity, gravitation, the development of quantum physics and concepts of space and time); part 3, Einstein's letters; part 4, Einstein's writings (including accounts of electrodynamics of moving bodies, general relativity, method of theoretical physics and an elementary derivation of the equivalence of mass and energy). (U.K.)

  12. Seismic fragility of nuclear power plant components (Phase 2): A fragility handbook on eighteen components

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.; Kassir, M.K.; Shteyngart, S.

    1991-06-01

    Fragility estimates of seven equipment classes were published in earlier reports. This report presents fragility analysis results from eleven additional equipment categories. The fragility levels are expressed in probabilistic terms. For users' convenience, this concluding report includes a summary of fragility results of all eighteen equipment classes. A set of conversion factors based on judgment is recommended for use of the information for early vintage equipment. The knowledge gained in conducting the Component Fragility Program and similar other programs is expected to provide a new direction for seismic verification and qualification of equipment. 15 refs., 12 tabs

  13. Charged Rényi entropies in CFTs with Einstein-Gauss-Bonnet holographic duals

    Science.gov (United States)

    Pastras, Georgios; Manolopoulos, Dimitrios

    2014-11-01

    We calculate the Rényi entropy S q ( μ, λ), for spherical entangling surfaces in CFT's with Einstein-Gauss-Bonnet-Maxwell holographic duals. Rényi entropies must obey some interesting inequalities by definition. However, for Gauss-Bonnet couplings λ, larger than specific value, but still allowed by causality, we observe a violation of the inequality , which is related to the existence of negative entropy black holes, providing interesting restrictions in the bulk theory. Moreover, we find an interesting distinction of the behaviour of the analytic continuation of S q ( μ, λ) for imaginary chemical potential, between negative and non-negative λ.

  14. The ultimate quotable Einstein

    CERN Document Server

    2011-01-01

    Here is the definitive new edition of the hugely popular collection of Einstein quotations that has sold tens of thousands of copies worldwide and been translated into twenty-five languages. The Ultimate Quotable Einstein features 400 additional quotes, bringing the total to roughly 1,600 in all. This ultimate edition includes new sections--"On and to Children," "On Race and Prejudice," and "Einstein's Verses: A Small Selection"--as well as a chronology of Einstein's life and accomplishments, Freeman Dyson's authoritative foreword, and new commentary by Alice Calaprice.

  15. Einstein from 'B' to 'Z'

    CERN Document Server

    Stachel, John

    2002-01-01

    John Stachel, the author of this collection of 37 published and unpublished articles on Albert Einstein, has written about Einstein and his work for over 40 years. Trained as a theoretical physicist specializing in the theory of relativity, he was chosen as the founding editor of The Collected papers of Albert Einstein 25 years ago, and is currently Director of the Boston University Center for Einstein Studies. Based on a detailed study of documentary evidence, much of which was newly discovered in the course of his work, Stachel debunks many of the old (and some new) myths about Einstein and offers novel insight into his life and work. Throughout the volume, a new, more human picture of Einstein is offered to replace the plaster saint of popular legend. In particular, a youthful Einstein emerges from the obscurity that previously shrouded his early years, and much new light is shed on the origins of the special and general theories of relativity. Also discussed in some detail are Einstein's troubled relatio...

  16. Einstein

    CERN Document Server

    Smith, Peter D

    2003-01-01

    Albert Einstein re-wrote the textbooks of science in 1905: physics since has been little more than a series of footnotes to the theories of a 26-year-old patent-office clerk. Einstein's science and emotional life come together in this vivid portrait of a rebellious and contradictory figure, a pacifist whose legendary equation E=mc2 opened scientists' eyes to the terrible power within every atom. 'To punish me for my contempt for authority,' he lamented, 'Fate has made me an authority myself.'

  17. Fragile X-associated tremor/ataxia syndrome: another phenotype of the fragile X gene.

    Science.gov (United States)

    Hessl, David; Grigsby, Jim

    2016-08-01

    Neuropsychologists have an important role in evaluating patients with fragile X-associated disorders, but most practitioners are unaware of the recently identified neurodegenerative movement disorder known as fragile X-associated tremor ataxia syndrome (FXTAS). The objective of this editorial is to orient the reader to FXTAS and highlight the importance of clinical neuropsychology in describing the fragile X premutation phenotype and the role practitioners may have in assessing and monitoring patients with or at risk for neurodegeneration. We issued a call for papers for the special issue, highlighting the primary objective of familiarizing clinical neuropsychologists with FXTAS, and with the neuropsychological phenotype of both male and female asymptomatic carriers. Eight papers are included, including an overview of the fragile X-associated disorders (Grigsby), a review of the neuroradiological and neurological aspects of FXTAS and how the disorder compares to other movement disorders (O'Keefe et al.), a perspective on the prominence of white matter disease and dementia in FXTAS (Filley), and a review of mouse models of FXTAS (Foote). There are four research papers, including one on self-reported memory problems in FXTAS (Birch et al.), and three papers focused on the neuropsychiatric aspects of the fragile X premutation, a review (Bourgeois), an examination of autism-related traits (Schneider), and a research paper on executive functioning and psychopathology (Grigsby). The issue highlights the importance of awareness of fragile X-associated disorders for neuropsychologists, an awareness that must reach beyond neurodevelopmental aspects related to fragile X syndrome into the realm of neurodegenerative disease and aging.

  18. Apparent Violation of the Fluctuation-Dissipation Theorem due to Dynamic Heterogeneity in a Model Glass-Forming Liquid

    International Nuclear Information System (INIS)

    Kawasaki, Takeshi; Tanaka, Hajime

    2009-01-01

    Here we study the relation between the mobility and the translational diffusion in supercooled two-dimensional polydisperse colloidal liquids, using numerical simulations. We find an apparent violation of the Einstein-Smoluchowski (ES) relation D=k B Tμ (D: diffusion constant; μ: mobility; k B ; Boltzmann's constant; T: temperature). The violation is a direct consequence of the fact that it is difficult for a driven particle to enter a jammed region with high order due to its yield stress. The degree of this apparent ES violation is controlled solely by the characteristic size of slow jammed regions, ξ. Our finding implies that the characteristic time of this problem is not the structural relaxation time τ α but the lifetime of dynamic heterogeneity, τ ξ . A supercooled liquid can be regarded to be ergodic only over τ ξ , which may be the slowest intrinsic time scale of the system.

  19. Scattering amplitudes in N=2 Maxwell-Einstein and Yang-Mills/Einstein supergravity

    CERN Document Server

    Chiodaroli, Marco; Johansson, Henrik; Roiban, Radu

    2015-01-01

    We expose a double-copy structure in the scattering amplitudes of the generic Jordan family of N=2 Maxwell-Einstein and Yang-Mills/Einstein supergravity theories in four and five dimensions. The Maxwell-Einstein supergravity amplitudes are obtained through the color/kinematics duality as a product of two gauge-theory factors; one originating from pure N=2 super-Yang-Mills theory and the other from the dimensional reduction of a bosonic higher-dimensional pure Yang-Mills theory. We identify a specific symplectic frame in four dimensions for which the on-shell fields and amplitudes from the double-copy construction can be identified with the ones obtained from the supergravity Lagrangian and Feynman-rule computations. The Yang-Mills/Einstein supergravity theories are obtained by gauging a compact subgroup of the isometry group of their Maxwell-Einstein counterparts. For the generic Jordan family this process is identified with the introduction of cubic scalar couplings on the bosonic gauge-theory side, which th...

  20. Violation of Bell's inequality with continuous spatial variables

    International Nuclear Information System (INIS)

    Abouraddy, Ayman F.; Yarnall, Timothy; Saleh, Bahaa E. A.; Teich, Malvin C.

    2007-01-01

    The Einstein-Podolsky-Rosen (EPR) argument revealed the paradoxical properties of a two-particle system entangled continuously in the spatial parameter. Yet a direct test of quantum nonlocality exhibited by this state, via a violation of Bell's inequality, has not been forthcoming. In this paper, we identify and construct experimental arrangements comprising simple optical components, without nonlinearities or moving parts, that implement operators in the spatial-parity space of single-photon fields that correspond to the familiar Pauli spin operators. We achieve this by first establishing an isomorphism between the single-mode multiphoton electromagnetic-field space spanned by a Fock-state basis and the single-photon multimode electromagnetic-field space spanned by a spatial-eigenmode basis. We then proceed to construct a Hilbert space with a two-dimensional basis of spatial even-odd parity modes. In particular, we describe an arrangement that implements a rotation in the parity space of each photon of an entangled-photon pair, allowing for a straightforward experimental test of Bell's inequality using the EPR state. Finally, the violation of a Bell inequality is quantified in terms of the physical parameters of the two-photon source

  1. Albert Einstein a biography

    CERN Document Server

    Fölsing, Albrecht

    1997-01-01

    Albert Einstein's achievements are not just milestones in the history of science; decades ago they became an integral part of the twentieth-century world in which we live. Like no other modern physicist he altered and expanded our understanding of nature. Like few other scholars, he stood fully in the public eye. In a world changing with dramatic rapidity, he embodied the role of the scientist by personal example. Albrecht Folsing, relying on previously unknown sources and letters, brings Einstein's "genius" into focus. Whereas former biographies, written in the tradition of the history of science, seem to describe a heroic Einstein who fell to earth from heaven, Folsing attempts to reconstruct Einstein's thought in the context of the state of research at the turn of the century. Thus, perhaps for the first time, Einstein's surroundings come to light.

  2. Einstein's statistical mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Baracca, A; Rechtman S, R

    1985-08-01

    The foundation of equilibrium classical statistical mechanics were laid down in 1902 independently by Gibbs and Einstein. The latter's contribution, developed in three papers published between 1902 and 1904, is usually forgotten and when not, rapidly dismissed as equivalent to Gibb's. We review in detail Einstein's ideas on the foundations of statistical mechanics and show that they constitute the beginning of a research program that led Einstein to quantum theory. We also show how these ideas may be used as a starting point for an introductory course on the subject.

  3. Einstein's statistical mechanics

    International Nuclear Information System (INIS)

    Baracca, A.; Rechtman S, R.

    1985-01-01

    The foundation of equilibrium classical statistical mechanics were laid down in 1902 independently by Gibbs and Einstein. The latter's contribution, developed in three papers published between 1902 and 1904, is usually forgotten and when not, rapidly dismissed as equivalent to Gibb's. We review in detail Einstein's ideas on the foundations of statistical mechanics and show that they constitute the beginning of a research program that led Einstein to quantum theory. We also show how these ideas may be used as a starting point for an introductory course on the subject. (author)

  4. Einstein algebras and general relativity

    International Nuclear Information System (INIS)

    Heller, M.

    1992-01-01

    A purely algebraic structure called an Einstein algebra is defined in such a way that every spacetime satisfying Einstein's equations is an Einstein algebra but not vice versa. The Gelfand representation of Einstein algebras is defined, and two of its subrepresentations are discussed. One of them is equivalent to the global formulation of the standard theory of general relativity; the other one leads to a more general theory of gravitation which, in particular, includes so-called regular singularities. In order to include other types of singularities one must change to sheaves of Einstein algebras. They are defined and briefly discussed. As a test of the proposed method, the sheaf of Einstein algebras corresponding to the space-time of a straight cosmic string with quasiregular singularity is constructed. 22 refs

  5. Albert Einsteins Wonderjaar

    NARCIS (Netherlands)

    Dieks, D.G.B.J.

    In het jaar 1905 publiceerde Albert Einstein een reeks artikelen die een omwenteling voor de wetenschap betekende. En toch bleef Einstein een kind van zijn tijd, van een eeuw die in het teken stond van dynamo’s, raderen en stoommachines.

  6. Observation of anomalous Stokes versus anti-Stokes ratio in MoTe2 atomic layers

    Science.gov (United States)

    Goldstein, Thomas; Chen, Shao-Yu; Xiao, Di; Ramasubramaniam, Ashwin; Yan, Jun

    We grow hexagonal molybdenum ditelluride (MoTe2), a prototypical transition metal dichalcogenide (TMDC) semiconductor, with chemical vapor transport methods and investigate its atomic layers with Stokes and anti-Stokes Raman scattering. We report observation of all six types of zone center optical phonons. Quite remarkably, the anti-Stokes Raman intensity of the low energy layer-breathing mode becomes more intense than the Stokes peak under certain experimental conditions, creating an illusion of 'negative temperature'. This effect is tunable, and can be switched from anti-Stokes enhancement to suppression by varying the excitation wavelength. We interpret this observation to be a result of resonance effects arising from the C excitons in the vicinity of the Brillouin zone center, which are robust even for multiple layers of MoTe2. The intense anti-Stokes Raman scattering provides a cooling channel for the crystal and opens up opportunities for laser cooling of atomically thin TMDC semiconductor devices. Supported by the University of Massachusetts Amherst, the National Science Foundation Center for Hierarchical Manufacturing (CMMI-1025020) and Office of Emerging Frontiers in Research and Innovation (EFRI-1433496).

  7. Rediscovering Einstein's legacy: How Einstein anticipates Kuhn and Feyerabend on the nature of science.

    Science.gov (United States)

    Oberheim, Eric

    2016-06-01

    Thomas Kuhn and Paul Feyerabend promote incommensurability as a central component of their conflicting accounts of the nature of science. This paper argues that in so doing, they both develop Albert Einstein's views, albeit in different directions. Einstein describes scientific revolutions as conceptual replacements, not mere revisions, endorsing 'Kant-on-wheels' metaphysics in light of 'world change'. Einstein emphasizes underdetermination of theory by evidence, rational disagreement in theory choice, and the non-neutrality of empirical evidence. Einstein even uses the term 'incommensurable' specifically to apply to challenges posed to comparatively evaluating scientific theories in 1949, more than a decade before Kuhn and Feyerabend. This analysis shows how Einstein anticipates substantial components of Kuhn and Feyerabend's views, and suggests that there are strong reasons to suspect that Kuhn and Feyerabend were directly inspired by Einstein's use of the term 'incommensurable', as well as his more general methodological and philosophical reflections. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Nonlocality of the original Einstein-Podolsky-Rosen state

    Science.gov (United States)

    Cohen, O.

    1997-11-01

    We examine the properties and behavior of the original Einstein-Podolsky-Rosen (EPR) wave function [Phys. Rev. 47, 777 (1935)] and related Gaussian-correlated wave functions. We assess the degree of entanglement of these wave functions and consider an argument of Bell [Ann. (N.Y.) Acad. Sci. 480, 263 (1986)] based on the Wigner phase-space distribution [Phys. Rev. 40, 749 (1932)], which implies that the original EPR correlations can accommodate a local hidden-variable description. We extend Bell's analysis to the related Gaussian wave functions. We then show that it is possible to identify definite nonlocal aspects for the original EPR state and related states. We describe possible experiments that would demonstrate these nonlocal features through violations of Bell inequalities. The implications of our results, and in particular their relevance for the causal interpretation of quantum mechanics, are considered.

  9. Einstein and cosmology

    International Nuclear Information System (INIS)

    Gekman, O.

    1982-01-01

    The brief essay of the development of the main ideas of relativistic cosmology is presented. The Einstein's cosmological work about the Universe - ''Cosmological considerations in connection with the general relativity theory'' - gave the basis to all further treatments in this field. In 1922 A. Friedman's work appeared, in which the first expanding Universe model was proposed as a solution of the Einstein field equations. The model was spherically closed, but its curvature radius was a function of time. About 1955 the searches for anisotropic homogeneous solutions to Einstein field equation began. It turned out that isotropic cosmological models are unstable in general. The predominant part of them transform to anisotropic at insignificant breaking of isotropy. The discovery of isotropic background cosmic radiation in 1965, along with the Hubble low of the Universe expansion, served as the direct confirmation of cosmology based on the Einstein theory

  10. Quantum tunneling time of a Bose-Einstein condensate traversing through a laser-induced potential barrier

    International Nuclear Information System (INIS)

    Duan Zhenglu; Fan Bixuan; Yuan Chunhua; Zhang Weiping; Cheng Jing; Zhu Shiyao

    2010-01-01

    We theoretically study the effect of atomic nonlinearity on the tunneling time in the case of an atomic Bose-Einstein condensate (BEC) traversing the laser-induced potential barrier. The atomic nonlinearity is controlled to appear only in the region of the barrier by employing the Feshbach resonance technique to tune interatomic interaction in the tunneling process. Numerical simulation shows that the atomic nonlinear effect dramatically changes the tunneling behavior of the BEC matter wave packet and results in the violation of the Hartman effect and the occurrence of negative tunneling time.

  11. Einstein-Podolsky-Rosen Entanglement of Narrow-Band Photons from Cold Atoms

    Science.gov (United States)

    Lee, Jong-Chan; Park, Kwang-Kyoon; Zhao, Tian-Ming; Kim, Yoon-Ho

    2016-12-01

    Einstein-Podolsky-Rosen (EPR) entanglement introduced in 1935 deals with two particles that are entangled in their positions and momenta. Here we report the first experimental demonstration of EPR position-momentum entanglement of narrow-band photon pairs generated from cold atoms. By using two-photon quantum ghost imaging and ghost interference, we demonstrate explicitly that the narrow-band photon pairs violate the separability criterion, confirming EPR entanglement. We further demonstrate continuous variable EPR steering for positions and momenta of the two photons. Our new source of EPR-entangled narrow-band photons is expected to play an essential role in spatially multiplexed quantum information processing, such as, storage of quantum correlated images, quantum interface involving hyperentangled photons, etc.

  12. Einstein-Podolsky-Rosen Entanglement of Narrow-Band Photons from Cold Atoms.

    Science.gov (United States)

    Lee, Jong-Chan; Park, Kwang-Kyoon; Zhao, Tian-Ming; Kim, Yoon-Ho

    2016-12-16

    Einstein-Podolsky-Rosen (EPR) entanglement introduced in 1935 deals with two particles that are entangled in their positions and momenta. Here we report the first experimental demonstration of EPR position-momentum entanglement of narrow-band photon pairs generated from cold atoms. By using two-photon quantum ghost imaging and ghost interference, we demonstrate explicitly that the narrow-band photon pairs violate the separability criterion, confirming EPR entanglement. We further demonstrate continuous variable EPR steering for positions and momenta of the two photons. Our new source of EPR-entangled narrow-band photons is expected to play an essential role in spatially multiplexed quantum information processing, such as, storage of quantum correlated images, quantum interface involving hyperentangled photons, etc.

  13. Genetics Home Reference: fragile X syndrome

    Science.gov (United States)

    ... Facebook Twitter Home Health Conditions Fragile X syndrome Fragile X syndrome Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Fragile X syndrome is a genetic condition that causes a ...

  14. De Sitter en Einstein. ‘Het lijkt mij dat Einstein hier een vergissing begaan heeft’

    Directory of Open Access Journals (Sweden)

    Jan Guichelaar

    2016-10-01

    Full Text Available De Sitter and EinsteinWillem de Sitter’s interest in gravity was based on his work on celestial mechanics, in particular on the four big moons of Jupiter. His work on cosmology was based on the general theory of relativity of Albert Einstein. De Sitter published in 1917, on request of Arthur Eddington to inform the English astronomers, a series of four articles in The Observatory and the Monthly Notices of the Royal Astronomical Society. Einstein developed his own cosmological models, containing mass. De Sitter found a different solution and described a universe without mass. Einstein could not accept De Sitter’s model and they ‘fought out’ two controversies in their correspondence. In theend Einstein had to confess De Sitter was mainly right in his criticisms. In 1932 Einstein and De Sitter published an article on a new model, the so-called Einstein-De Sitter Model of the universe. So, De Sitter was able to do fundamental work in classical celestial mechanics as well as in the new cosmological theories.

  15. Violation of Bell’s inequality: Must the Einstein locality really be abandoned?

    Science.gov (United States)

    Jung, Kurt

    2017-08-01

    Since John Bell has established his famous inequality and several independent experiments have confirmed the distinct polarization correlation of entangled photons predicted by quantum mechanics it is evident that quantum mechanics cannot be explained by local realistic theories. Actually, the observed polarization correlation can be deduced from wave optical considerations. The correlation has its origin in the phase coupling of the two circularly polarized wave packets leaving the photon source simultaneously. The experimental results violate Bell’s inequality although no non-local interactions have to be assumed. In consequence the principle of locality remains valid in the scope of quantum mechanics. However, the principle of realism has to be replaced by the less stringent principle of contextuality.

  16. Einstein-Rosen gravitational waves

    International Nuclear Information System (INIS)

    Astefanoaei, Iordana; Maftei, Gh.

    2001-01-01

    In this paper we analyse the behaviour of the gravitational waves in the approximation of the far matter fields, considering the indirect interaction between the matter sources and the gravitational field, in a cosmological model based on the Einstein-Rosen solution, Because the properties of the gravitational waves obtained as the solutions of Einstein fields equations (the gravitational field equations) are most obvious in the weak gravitational fields we consider here, the gravitational field in the linear approximation. Using the Newman-Penrose formalism, we calculate in the null-tetradic base (e a ), the spin coefficients, the directional derivates and the tetradic components of Ricci and Weyl tensors. From the Einstein field equations we obtained the solution for b(z, t) what described the behaviour of gravitational wave in Einstein-Rosen Universe and in the particular case, when t → ∞, p(z, t) leads us to the primordial gravitational waves in the Einstein-Rosen Universe. (authors)

  17. Holonomy of Einstein Lorentzian manifolds

    International Nuclear Information System (INIS)

    Galaev, Anton S

    2010-01-01

    The classification of all possible holonomy algebras of Einstein and vacuum Einstein Lorentzian manifolds is obtained. It is shown that each such algebra appears as the holonomy algebra of an Einstein (resp. vacuum Einstein) Lorentzian manifold; the direct constructions are given. Also the holonomy algebras of totally Ricci-isotropic Lorentzian manifolds are classified. The classification of the holonomy algebras of Lorentzian manifolds is reviewed and a complete description of the spaces of curvature tensors for these holonomies is given.

  18. Einstein (1879-1955)

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    In the first part of this book a historical review of Einstein life and works are presented. In the second part papers about different aspects of quantum mechanics are given. The third part is devoted to a round table on Einstein, Podolski and Rosen paradox [fr

  19. New Einstein-Sasaki and Einstein spaces from Kerr-de Sitter

    International Nuclear Information System (INIS)

    Cvetic, M.; Lue, H.; Pope, C.N.; Page, Don N.

    2009-01-01

    In this paper, which is an elaboration of our results in Phys. Rev. Lett. 95:071101, 2005 (hep-th/0504225), we construct new Einstein-Sasaki spaces L p,q,r 1 ,...,r n-1 in all odd dimensions D = 2n+1 ≥ 5. They arise by taking certain BPS limits of the Euclideanised Kerr-de Sitter metrics. This yields local Einstein-Sasaki metrics of cohomogeneity n, with toric U(1) n+1 principal orbits, and n real non-trivial parameters. By studying the structure of the degenerate orbits we show that for appropriate choices of the parameters, characterised by the (n+1) coprime integers (p,q,r 1 ,...,r n-1 ), the local metrics extend smoothly onto complete and non-singular compact Einstein-Sasaki manifolds L p,q,r 1 ,...,r n-1 . We also construct new complete and non-singular compact Einstein spaces Λ p,q,r 1 ,...,r n in D = 2n+1 that are not Sasakian, by choosing parameters appropriately in the Euclideanised Kerr-de Sitter metrics when no BPS limit is taken.

  20. Once upon Einstein

    CERN Document Server

    Damour, Thibault

    2006-01-01

    It is well known that Einstein founded twentieth-century physics with his work on relativity and quanta, but what do we really know about these ground breaking ideas? How were they discovered? What should we retain today from the conceptual upheavals he initiated? Through a selection of concrete scenes taken from Einstein's life, the author offers a view into the formation of his theories, as well as reminders of the day-to-day applications of his ideas. Simultaneously the reader is lead through a reflection on their philosophical impact: How should we think of time according to the theory of relativity, which removes any meaningful "now" and shows that twins can have different ages? How should we think of reality when quantum theory predicts that spatially separated objects nevertheless remain connected through Einstein's notion of "entanglement," which has recently been verified through scientific observation? This book puts readers in Einstein's place, allowing them to share some of those particular moment...

  1. Albert Einstein Centenary

    CERN Document Server

    Weisskopf, Victor Frederick; CERN. Geneva

    1979-01-01

    A socially engaged scientist by V. F. WEISSKOPF. On the origin of the Einstein-Russell statement on nuclear weapon by H. S. BURHOP. This week, we pay homage to Albert Einstein, the giant of twentieth-century physics born exactly 100 years ago on 14 March 1879 in Ulm, Germany. At the height of his career, Einstein made a whole series of monumental contributions to physics, including the elaborate theories of special and general relativity which revolutionized human thought and marked a major breakthrough in our understanding to the Universe. Along with quantum mechanics, relativity is one of the twin pillars of understanding which allow us here at CERN to study the behaviour of the tiniest components of matter. The development of quantum mechanics took the combined efforts of some of the greatest scientists the world has known, while relativity was developed almost single-handed by Einstein. The centenary of his birth is being commemorated all over the world. Exhibitions and symposia are being organized, books...

  2. An Einstein encyclopedia

    CERN Document Server

    Calaprice, Alice; Schulmann, Robert

    2015-01-01

    This is the single most complete guide to Albert Einstein’s life and work for students, researchers, and browsers alike. Written by three leading Einstein scholars who draw on their combined wealth of expertise gained during their work on the Collected Papers of Albert Einstein, this authoritative and accessible reference features more than one hundred entries and is divided into three parts covering the personal, scientific, and public spheres of Einstein’s life. An Einstein Encyclopedia contains entries on Einstein’s birth and death, family and romantic relationships, honors and awards, educational institutions where he studied and worked, citizenships and immigration to America, hobbies and travels, plus the people he befriended and the history of his archives and the Einstein Papers Project. Entries on Einstein’s scientific theories provide useful background and context, along with details about his assistants, collaborators, and rivals, as well as physics concepts related to his work. Coverage o...

  3. Quantum entanglement: facts and fiction - how wrong was Einstein after all?

    Science.gov (United States)

    Nordén, Bengt

    2016-01-01

    Einstein was wrong with his 1927 Solvay Conference claim that quantum mechanics is incomplete and incapable of describing diffraction of single particles. However, the Einstein-Podolsky-Rosen paradox of entangled pairs of particles remains lurking with its 'spooky action at a distance'. In molecules quantum entanglement can be viewed as basis of both chemical bonding and excitonic states. The latter are important in many biophysical contexts and involve coupling between subsystems in which virtual excitations lead to eigenstates of the total Hamiltonian, but not for the separate subsystems. The author questions whether atomic or photonic systems may be probed to prove that particles or photons may stay entangled over large distances and display the immediate communication with each other that so concerned Einstein. A dissociating hydrogen molecule is taken as a model of a zero-spin entangled system whose angular momenta are in principle possible to probe for this purpose. In practice, however, spins randomize as a result of interactions with surrounding fields and matter. Similarly, no experiment seems yet to provide unambiguous evidence of remaining entanglement between single photons at large separations in absence of mutual interaction, or about immediate (superluminal) communication. This forces us to reflect again on what Einstein really had in mind with the paradox, viz. a probabilistic interpretation of a wave function for an ensemble of identically prepared states, rather than as a statement about single particles. Such a prepared state of many particles would lack properties of quantum entanglement that make it so special, including the uncertainty upon which safe quantum communication is assumed to rest. An example is Zewail's experiment showing visible resonance in the dissociation of a coherently vibrating ensemble of NaI molecules apparently violating the uncertainty principle. Einstein was wrong about diffracting single photons where space-like anti

  4. Multiphonon-assisted anti-Stokes and Stokes fluorescence of triply ionized rare-earth ions

    International Nuclear Information System (INIS)

    Auzel, F.

    1976-01-01

    Experimental demonstration of multiphonon-assisted anti-Stokes and Stokes excitation of rare-earth ions (R 3+ ) in different hosts, that is, in a weak-coupling ion-lattice interaction case, is obtained. An exponential behavior of excitation probabilities with respect to energy difference between excitation and electronic line is found just as for multiphonon-assisted nonradiative decay and energy transfer. Exponential parameters α/sub As/ and α/sub S/ for anti-Stokes and Stokes excitation are measured and linked to the Miyakawa-Dexter α parameter for decay, leading to estimates for Pekar-Huang-Rhys coupling parameter S 0 of about 0.04, in agreement with values obtained from one-phonon spectra or nonradiative-decay measurements. A semiempirical formula is deduced to obtain α from only one parameter, an effective phonon energy

  5. Incompressible Navier-Stokes and parabolized Navier-Stokes solution procedures and computational techniques

    Science.gov (United States)

    Rubin, S. G.

    1982-01-01

    Recent developments with finite-difference techniques are emphasized. The quotation marks reflect the fact that any finite discretization procedure can be included in this category. Many so-called finite element collocation and galerkin methods can be reproduced by appropriate forms of the differential equations and discretization formulas. Many of the difficulties encountered in early Navier-Stokes calculations were inherent not only in the choice of the different equations (accuracy), but also in the method of solution or choice of algorithm (convergence and stability, in the manner in which the dependent variables or discretized equations are related (coupling), in the manner that boundary conditions are applied, in the manner that the coordinate mesh is specified (grid generation), and finally, in recognizing that for many high Reynolds number flows not all contributions to the Navier-Stokes equations are necessarily of equal importance (parabolization, preferred direction, pressure interaction, asymptotic and mathematical character). It is these elements that are reviewed. Several Navier-Stokes and parabolized Navier-Stokes formulations are also presented.

  6. Neuromythology of Einstein's brain.

    Science.gov (United States)

    Hines, Terence

    2014-07-01

    The idea that the brain of the great physicist Albert Einstein is different from "average" brains in both cellular structure and external shape is widespread. This belief is based on several studies examining Einstein's brain both histologically and morphologically. This paper reviews these studies and finds them wanting. Their results do not, in fact, provide support for the claim that the structure of Einstein's brain reflects his intellectual abilities. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Systems fragility: The sociology of chaos.

    Science.gov (United States)

    Hodges, Lori R

    2016-01-01

    This article examines the concept of community fragility in emergency management from a systems perspective. Using literature that addresses fragility in four areas of complex systems, including ecosystems, social systems, sociotechnical systems, and complex adaptive systems, a theoretical framework focused on the emergency management field is created. These findings illustrate how community fragility factors can be used in the emergency management field to not only improve overall outcomes after disaster but also build less fragile systems and communities in preparation for future disasters.

  8. How Einstein changed the world

    International Nuclear Information System (INIS)

    Boudenot, J.C.

    2005-01-01

    This book allows the reader to understand in a simple but detailed way the importance of the work of Einstein and its implications in the physics of today. The author first draws a biography of Einstein, then outlines the knowledge of physics at the beginning of the twentieth century, then describes the major contributions of Einstein to the brownian motion, the mass-energy equivalence, relativity and the notion of quantum, and ends by showing that the life-long Einstein's quest for a unitarian theory is still a present-day issue. (A.C.)

  9. Generalized Stokes eignefunctions: a new trial basis for the solution of incompressible Navier-Stokes equations

    International Nuclear Information System (INIS)

    Batcho, P.F.; Karniadakis, G.E.

    1994-01-01

    The present study focuses on the solution of the incompressible Navier-Stokes equations in general, non-separable domains, and employs a Galerkin projection of divergence-free vector functions as a trail basis. This basis is obtained from the solution of a generalized constrained Stokes eigen-problem in the domain of interest. Faster convergence can be achieved by constructing a singular Stokes eigen-problem in which the Stokes operator is modified to include a variable coefficient which vanishes at the domain boundaries. The convergence properties of such functions are advantageous in a least squares sense and are shown to produce significantly better approximations to the solution of the Navier-Stokes equations in post-critical states where unsteadiness characterizes the flowfield. Solutions for the eigen-systems are efficiently accomplished using a combined Lanczos-Uzawa algorithm and spectral element discretizations. Results are presented for different simulations using these global spectral trial basis on non-separable and multiply-connected domains. It is confirmed that faster convergence is obtained using the singular eigen-expansions in approximating stationary Navier-Stokes solutions in general domains. It is also shown that 100-mode expansions of time-dependent solutions based on the singular Stokes eigenfunctions are sufficient to accurately predict the dynamics of flows in such domains, including Hopf bifurcations, intermittency, and details of flow structures

  10. Once Upon Einstein

    International Nuclear Information System (INIS)

    Giannetto, E

    2007-01-01

    Thibault Damour is a theoretical physicist, and a member of the French Academy of Sciences. This book is the translation, by Eric Novak, of the original French Si Einstein m'etait conte (Le Cherche Midi, 2005). It is neither a book of theoretical physics nor a biography of Einstein. It is not a book of history nor philosophy of science. In Damour's words it was written to encourage the reader to share with Einstein 'those times when he understood some part of the hidden order of the universe'. It is a relatively short book, written in a very fluent style, but it deals with all the major problems and achievements of Einstein's works. Starting from special relativity, it continues with general relativity, quantum theories, unified field theory and a brief overview of the actual research related to Einstein's legacy. It is essentially a popular science book with some related exploration in history and philosophy to interpret physical theories. The most important problem discussed by Damour is the nature of time. On this subject, there is a very interesting short paragraph (pp 33--35) dedicated to the reception of the relativity idea by the great writer Marcel Proust and its counterpart within A la Recherche du Temps Perdu. A correct discussion of the implications of a relativistic time should imply the distinction of the different possible interpretations of this concept. Damour seems to conclude that only one interpretation is possible: 'time does not exist', flowing of time is an illusion. One has to know that Einstein's ideas on time were related to Spinoza's perspective of a knowledge sub specie aeternitatis. However, other interpretations are possible and are related to the idea of time as an actuality. Damour speaks about the controversy between Einstein and Bergson, but Bergson is considered as a philosopher who did not understand relativity. This philosophical problem of relativistic time is indeed related to a historical problem briefly discussed by Damour

  11. Einstein-Rosen 'bridge' needs lightlike brane source

    International Nuclear Information System (INIS)

    Guendelman, Eduardo; Kaganovich, Alexander; Nissimov, Emil; Pacheva, Svetlana

    2009-01-01

    The Einstein-Rosen 'bridge' wormhole solution proposed in the classic paper (Einstein and Rosen (1935) ) does not satisfy the vacuum Einstein equations at the wormhole throat. We show that the fully consistent formulation of the original Einstein-Rosen 'bridge' requires solving Einstein equations of bulk D=4 gravity coupled to a lightlike brane with a well-defined world-volume action. The non-vanishing contribution of Einstein-Rosen 'bridge' solution to the right-hand side of Einstein equations at the throat matches precisely the surface stress-energy tensor of the lightlike brane which automatically occupies the throat ('horizon straddling') - a feature triggered by the world-volume lightlike brane dynamics.

  12. Einstein's daughter the search for Lieserl

    CERN Document Server

    Zackheim, Michele

    1999-01-01

    A thoroughly gripping and groundbreaking investigation into the mysterious fate of Albert Einstein's illegitimate daughter. Albert Einstein fell in love with Mileva Maric, the woman who would become his first wife, when they were students at the Zurich Polytechnic Institute. When Maric conceived a child out of wedlock, she went home to her family in Serbia to have the child. Lieserl Maric Einstein was born in 1902. Though Einstein and Maric married the following year, Lieserl was left in the care of her grandparents and never became a part of the Einstein family. In fact, her very existence was unknown until the recent discovery of a cache of letters between Einstein and Maric. The final reference to Lieserl comes in a September 1903 letter, when, at the age of approximately eighteen months, she simply disappears. What happened to Einstein's daughter is the most potent mystery to emerge from the mythology that surrounds one of the century's legendary figures, owing in large part to the careful and apparent...

  13. Fragile X syndrome and fragile X-associated disorders [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Akash Rajaratnam

    2017-12-01

    Full Text Available Fragile X syndrome (FXS is caused by a full mutation on the FMR1 gene and a subsequent lack of FMRP, the protein product of FMR1. FMRP plays a key role in regulating the translation of many proteins involved in maintaining neuronal synaptic connections; its deficiency may result in a range of intellectual disabilities, social deficits, psychiatric problems, and dysmorphic physical features. A range of clinical involvement is also associated with the FMR1 premutation, including fragile X-associated tremor ataxia syndrome, fragile X-associated primary ovarian insufficiency, psychiatric problems, hypertension, migraines, and autoimmune problems. Over the past few years, there have been a number of advances in our knowledge of FXS and fragile X-associated disorders, and each of these advances offers significant clinical implications. Among these developments are a better understanding of the clinical impact of the phenomenon known as mosaicism, the revelation that various types of mutations can cause FXS, and improvements in treatment for FXS.

  14. Conductivity of weakly disordered strange metals: From conformal to hyperscaling-violating regimes

    Directory of Open Access Journals (Sweden)

    Andrew Lucas

    2015-03-01

    Full Text Available We present a semi-analytic method for constructing holographic black holes that interpolate from anti-de Sitter space to hyperscaling-violating geometries. These are holographic duals of conformal field theories in the presence of an applied chemical potential, μ, at a non-zero temperature, T, and allow us to describe the crossover from ‘strange metal’ physics at T≪μ, to conformal physics at T≫μ. Our holographic technique adds an extra gauge field and exploits structure of the Einstein–Maxwell system to manifestly find 1-parameter families of solutions of the Einstein-matter system in terms of a small family of functions, obeying a nested set of differential equations. Using these interpolating geometries, we re-consider holographically some recent questions of interest about hyperscaling-violating field theories. Our focus is a more detailed holographic computation of the conductivity of strange metals, weakly perturbed by disorder coupled to scalar operators, including both the average conductivity as well as sample-to-sample fluctuations. Our findings are consistent with previous scaling arguments, though we point out logarithmic corrections in some special (holographic cases. We also discuss the nature of superconducting instabilities in hyperscaling-violating geometries with appropriate choices of scalar couplings.

  15. Bose-Einstein correlations

    International Nuclear Information System (INIS)

    Zalewski, Kacper

    2000-01-01

    The effect of Bose-Einstein correlations on multiplicity distributions of identical pions is discussed. It is found that these correlations affect significantly the observed multiplicity distributions, but Einstein's condensation is unlikely to be achieved, unless 'cold spots', i.e. regions, where groups of pions with very small relative momenta are produced, occur in high energy heavy-ion collisions

  16. Thermodynamics in Einstein's thought

    International Nuclear Information System (INIS)

    Klein, M.J.

    1983-01-01

    The role of the thermodynamical approach in the Einstein's scientific work is analyzed. The Einstein's development of a notion about statistical fluctuations of thermodynamical systems that leads him to discovery of corpuscular-wave dualism is retraced

  17. Einstein's philosophy of physics

    International Nuclear Information System (INIS)

    Seeger, R.J.

    1979-01-01

    Sources of Einstein's philosophical ideas are discussed. Einstein was indebted to Mach and Poincare, and espoused more or less a logical empiricism. He looked upon Nature as real, rational, and understandable, at least to an extent

  18. Three Faces of Fragile X.

    Science.gov (United States)

    Lieb-Lundell, Cornelia C E

    2016-11-01

    Fragile X syndrome (FXS) is the first of 3 syndromes identified as a health condition related to fragile X mental retardation (FMR1) gene dysfunction. The other 2 syndromes are fragile X-associated primary ovarian insufficiency syndrome (FXPOI) and fragile X-associated tremor/ataxia syndrome (FXTAS), which together are referred to as fragile X-associated disorders (FXDs). Collectively, this group comprises the 3 faces of fragile X. Even though the 3 conditions share a common genetic defect, each one is a separate health condition that results in a variety of body function impairments such as motor delay, musculoskeletal issues related to low muscle tone, coordination limitations, ataxia, tremor, undefined muscle aches and pains, and, for FXTAS, a late-onset neurodegeneration. Although each FXD condition may benefit from physical therapy intervention, available evidence as to the efficacy of intervention appropriate to FXDs is lacking. This perspective article will discuss the genetic basis of FMR1 gene dysfunction and describe health conditions related to this mutation, which have a range of expressions within a family. Physical therapy concerns and possible assessment and intervention strategies will be introduced. Understanding the intergenerational effect of the FMR1 mutation with potential life-span expression is a key component to identifying and treating the health conditions related to this specific genetic condition. © 2016 American Physical Therapy Association.

  19. Incarceration in fragile families.

    Science.gov (United States)

    Wildeman, Christopher; Western, Bruce

    2010-01-01

    Since the mid-1970s the U.S. imprisonment rate has increased roughly fivefold. As Christopher Wildeman and Bruce Western explain, the effects of this sea change in the imprisonment rate--commonly called mass imprisonment or the prison boom--have been concentrated among those most likely to form fragile families: poor and minority men with little schooling. Imprisonment diminishes the earnings of adult men, compromises their health, reduces familial resources, and contributes to family breakup. It also adds to the deficits of poor children, thus ensuring that the effects of imprisonment on inequality are transferred intergenerationally. Perversely, incarceration has its most corrosive effects on families whose fathers were involved in neither domestic violence nor violent crime before being imprisoned. Because having a parent go to prison is now so common for poor, minority children and so negatively affects them, the authors argue that mass imprisonment may increase future racial and class inequality--and may even lead to more crime in the long-term, thereby undoing any benefits of the prison boom. U.S. crime policy has thus, in the name of public safety, produced more vulnerable families and reduced the life chances of their children. Wildeman and Western advocate several policy reforms, such as limiting prison time for drug offenders and for parolees who violate the technical conditions of their parole, reconsidering sentence enhancements for repeat offenders, and expanding supports for prisoners and ex-prisoners. But Wildeman and Western argue that criminal justice reform alone will not solve the problems of school failure, joblessness, untreated addiction, and mental illness that pave the way to prison. In fact, focusing solely on criminal justice reforms would repeat the mistakes the nation made during the prison boom: trying to solve deep social problems with criminal justice policies. Addressing those broad problems, they say, requires a greater social

  20. Correspondence passed between Einstein and Schroedinger; La correspondance entre Einstein et Schroedinger

    Energy Technology Data Exchange (ETDEWEB)

    Balibar, F. [Paris-7 Univ., 75 (France)

    1992-12-31

    The main points of the 26 year long correspondence between Einstein and Schroedinger are reviewed: from the de Broglie thesis and the Bose-Einstein statistics to the Schroedinger equation (1925-1926); from the EPR paradox to the cat parable (1935); a complete collaboration on unitary theories.

  1. Einstein boundary conditions for the 3+1 Einstein equations

    International Nuclear Information System (INIS)

    Frittelli, Simonetta; Gomez, Roberto

    2003-01-01

    In the 3+1 framework of the Einstein equations for the case of a vanishing shift vector and arbitrary lapse, we calculate explicitly the four boundary equations arising from the vanishing of the projection of the Einstein tensor along the normal to the boundary surface of the initial-boundary value problem. Such conditions take the form of evolution equations along (as opposed to across) the boundary for certain components of the extrinsic curvature and for certain space derivatives of the three-metric. We argue that, in general, such boundary conditions do not follow necessarily from the evolution equations and the initial data, but need to be imposed on the boundary values of the fundamental variables. Using the Einstein-Christoffel formulation, which is strongly hyperbolic, we show how three of the boundary equations up to linear combinations should be used to prescribe the values of some incoming characteristic fields. Additionally, we show that the fourth one imposes conditions on some outgoing fields

  2. Applications of the EPR effect in the particle physics correlated decays of kaon and b-meson pairs with CP violation

    International Nuclear Information System (INIS)

    Lipkin, H. J.

    1989-11-01

    The Einstein-Podolsky-Rosen effect arises in particle physics when pairs of neutral K, D or B mesons are created in a definite quantum state, and the decays of the two mesons are correlated. Choosing the decay mode to be detected for one of the two mesons creates a 'polarized beam' on the other side which has interesting and usfull properties. Application to nvestigations of CP violation are discussed. (author)

  3. On some classes of super quasi-Einstein manifolds

    International Nuclear Information System (INIS)

    Ozguer, Cihan

    2009-01-01

    Quasi-Einstein and generalized quasi-Einstein manifolds are the generalizations of Einstein manifolds. In this study, we consider a super quasi-Einstein manifold, which is another generalization of an Einstein manifold. We find the curvature characterizations of a Ricci-pseudosymmetric and a quasi-conformally flat super quasi-Einstein manifolds. We also consider the condition C ∼ .S=0 on a super quasi-Einstein manifold, where C ∼ and S denote the quasi-conformal curvature tensor and Ricci tensor of the manifold, respectively.

  4. Once Upon Einstein

    Energy Technology Data Exchange (ETDEWEB)

    Giannetto, E [Dipartimento di Fisica ' A Volta' , via A Bassi 6, I-27100 Pavia (Italy)

    2007-07-20

    Thibault Damour is a theoretical physicist, and a member of the French Academy of Sciences. This book is the translation, by Eric Novak, of the original French Si Einstein m'etait conte (Le Cherche Midi, 2005). It is neither a book of theoretical physics nor a biography of Einstein. It is not a book of history nor philosophy of science. In Damour's words it was written to encourage the reader to share with Einstein 'those times when he understood some part of the hidden order of the universe'. It is a relatively short book, written in a very fluent style, but it deals with all the major problems and achievements of Einstein's works. Starting from special relativity, it continues with general relativity, quantum theories, unified field theory and a brief overview of the actual research related to Einstein's legacy. It is essentially a popular science book with some related exploration in history and philosophy to interpret physical theories. The most important problem discussed by Damour is the nature of time. On this subject, there is a very interesting short paragraph (pp 33--35) dedicated to the reception of the relativity idea by the great writer Marcel Proust and its counterpart within A la Recherche du Temps Perdu. A correct discussion of the implications of a relativistic time should imply the distinction of the different possible interpretations of this concept. Damour seems to conclude that only one interpretation is possible: 'time does not exist', flowing of time is an illusion. One has to know that Einstein's ideas on time were related to Spinoza's perspective of a knowledge sub specie aeternitatis. However, other interpretations are possible and are related to the idea of time as an actuality. Damour speaks about the controversy between Einstein and Bergson, but Bergson is considered as a philosopher who did not understand relativity. This philosophical problem of relativistic time is indeed related to a

  5. Structuring Stokes correlation functions using vector-vortex beam

    Science.gov (United States)

    Kumar, Vijay; Anwar, Ali; Singh, R. P.

    2018-01-01

    Higher order statistical correlations of the optical vector speckle field, formed due to scattering of a vector-vortex beam, are explored. Here, we report on the experimental construction of the Stokes parameters covariance matrix, consisting of all possible spatial Stokes parameters correlation functions. We also propose and experimentally realize a new Stokes correlation functions called Stokes field auto correlation functions. It is observed that the Stokes correlation functions of the vector-vortex beam will be reflected in the respective Stokes correlation functions of the corresponding vector speckle field. The major advantage of proposing Stokes correlation functions is that the Stokes correlation function can be easily tuned by manipulating the polarization of vector-vortex beam used to generate vector speckle field and to get the phase information directly from the intensity measurements. Moreover, this approach leads to a complete experimental Stokes characterization of a broad range of random fields.

  6. Conformal Einstein spaces

    International Nuclear Information System (INIS)

    Kozameh, C.N.; Newman, E.T.; Tod, K.P.

    1985-01-01

    Conformal transformations in four-dimensional. In particular, a new set of two necessary and sufficient conditions for a space to be conformal to an Einstein space is presented. The first condition defines the class of spaces conformal to C spaces, whereas the last one (the vanishing of the Bach tensor) gives the particular subclass of C spaces which are conformally related to Einstein spaces. (author)

  7. Scattering amplitudes in N=2 Maxwell-Einstein and Yang-Mills/Einstein supergravity

    International Nuclear Information System (INIS)

    Chiodaroli, Marco; Günaydin, Murat; Johansson, Henrik; Roiban, Radu

    2015-01-01

    We expose a double-copy structure in the scattering amplitudes of the generic Jordan family of N=2 Maxwell-Einstein and Yang-Mills/Einstein supergravity theories in four and five dimensions. The Maxwell-Einstein supergravity amplitudes are obtained through the color/kinematics duality as a product of two gauge-theory factors; one originating from pure N=2 super-Yang-Mills theory and the other from the dimensional reduction of a bosonic higher-dimensional pure Yang-Mills theory. We identify a specific symplectic frame in four dimensions for which the on-shell fields and amplitudes from the double-copy construction can be identified with the ones obtained from the supergravity Lagrangian and Feynman-rule computations. The Yang-Mills/Einstein supergravity theories are obtained by gauging a compact subgroup of the isometry group of their Maxwell-Einstein counterparts. For the generic Jordan family this process is identified with the introduction of cubic scalar couplings on the bosonic gauge-theory side, which through the double copy are responsible for the non-abelian vector interactions in the supergravity theory. As a demonstration of the power of this structure, we present explicit computations at tree-level and one loop. The double-copy construction allows us to obtain compact expressions for the supergravity superamplitudes, which are naturally organized as polynomials in the gauge coupling constant.

  8. New Stokes' line in WKB theory

    International Nuclear Information System (INIS)

    Berk, H.L.; Nevins, W.M.; Roberts, K.V.

    1982-01-01

    The WKB theory for differential equations of arbitrary order or integral equations in one dimension is investigated. The rules previously stated for the construction of Stokes' lines for Nth-order differential equations, N> or =3, or integral equations are found to be incomplete because these rules lead to asymptotic forms of the solutions that depend on path. This paradox is resolved by the demonstration that new Stokes' lines can arise when previously defined Stokes' lines cross. A new formulation of the WKB problem is given to justify the new Stokes' lines. With the new Stokes' lines, the asymptotic forms can be shown to be independent of path. In addition, the WKB eigenvalue problem is formulated, and the global dispersion relation is shown to be a functional of loop integrals of the action

  9. Effects of moderate pump and Stokes chirp on chirped-probe pulse femtosecond coherent anti-Stokes Raman scattering thermometry

    KAUST Repository

    Gu, Mingming; Satija, Aman; Lucht, Robert P.

    2018-01-01

    The effects of moderate levels of chirp in the pump and Stokes pulses on chirped-probe-pulse femtosecond coherent anti-Stokes Raman scattering (CPP fs CARS) were investigated. The frequency chirp in the pump and Stokes pulses was introduced

  10. Albert Einstein 1879-1955.

    Science.gov (United States)

    Physics Today, 1979

    1979-01-01

    Celebrates the centennial of Einstein's birth with an eight-page pictorial biography and two special articles: (1) Einstein the catalyst; and (2) Unitary field theories. His special and general theories of relativity and his contributions to quantum physics and other topics are also presented. (HM)

  11. Einstein: A Historical Perspective

    Science.gov (United States)

    Kormos-Buchwald, Diana

    2015-04-01

    In late 1915, Albert Einstein (1879-1955) completed as series of papers on a generalized theory of gravitation that were to constitute a major conceptual change in the history of modern physics and the crowning achievement of his scientific career. But this accomplishment came after a decade of intense intellectual struggle and was received with muted enthusiasm. Einstein's previously unpublished writings and massive correspondence, edited by the Einstein Papers Project, provide vivid insights into the historical, personal, and scientific context of the formulation, completion, and reception of GR during the first decades of the 20th century.

  12. An Einstein-Goedel universe

    International Nuclear Information System (INIS)

    Vaidya, P.C.

    1978-01-01

    The metric for the standard static Einstein model of the universe can be expressed in coordinates for which a congruence of spacelike world lines of the model will be twisting. A method of 'shifting the twist' has been devised by which the twist on spacelike world lines is shifted onto the timelike world lines. The model universe then becomes Goedel's model. A combined Einstein-Goedel model containing a parameter epsilon is obtained. Switching epsilon from +1 to -1 will effect the shift of twist in the world lines and lead from the Einstein model to the Goedel model. (author)

  13. Spacecraft Doppler tracking with possible violations of LLI and LPI: a theoretical modeling

    International Nuclear Information System (INIS)

    Deng Xue-Mei; Xie Yi

    2014-01-01

    Currently two-way and three-way spacecraft Doppler tracking techniques are widely used and play important roles in control and navigation of deep space missions. Starting from a one-way Doppler model, we extend the theory to two-way and three-way Doppler models by making them include possible violations of the local Lorentz invariance (LLI) and the local position invariance (LPI) in order to test the Einstein equivalence principle, which is the cornerstone of general relativity and all other metric theories of gravity. After taking the finite speed of light into account, which is the so-called light time solution (LTS), we make these models depend on the time of reception of the signal only for practical convenience. We find that possible violations of LLI and LPI cannot affect two-way Doppler tracking under a linear approximation of LTS, although this approximation is sufficiently good for most cases in the solar system. We also show that, in three-way Doppler tracking, possible violations of LLI and LPI are only associated with two stations, which suggests that it is better to set the stations at places with significant differences in velocities and gravitational potentials to obtain a high level of sensitivity for the tests

  14. Observation of one-way Einstein-Podolsky-Rosen steering

    Science.gov (United States)

    Händchen, Vitus; Eberle, Tobias; Steinlechner, Sebastian; Samblowski, Aiko; Franz, Torsten; Werner, Reinhard F.; Schnabel, Roman

    2012-09-01

    The distinctive non-classical features of quantum physics were first discussed in the seminal paper by A. Einstein, B. Podolsky and N. Rosen (EPR) in 1935. In his immediate response, E. Schrödinger introduced the notion of entanglement, now seen as the essential resource in quantum information as well as in quantum metrology. Furthermore, he showed that at the core of the EPR argument is a phenomenon that he called steering. In contrast to entanglement and violations of Bell's inequalities, steering implies a direction between the parties involved. Recent theoretical works have precisely defined this property, but the question arose as to whether there are bipartite states showing steering only in one direction. Here, we present an experimental realization of two entangled Gaussian modes of light that in fact shows the steering effect in one direction but not in the other. The generated one-way steering gives a new insight into quantum physics and may open a new field of applications in quantum information.

  15. Beyond Einstein

    Science.gov (United States)

    Hertz, P.

    2003-03-01

    The Structure and Evolution of the Universe (SEU) theme within NASA's Office of Space Science seeks to explore and understand the dynamic transformations of energy in the Universe - the entire web of biological and physical interactions that determine the evolution of our cosmic habitat. This search for understanding will enrich the human spirit and inspire a new generation of explorers, scientists, and engineers. To that end, NASA's strategic planning process has generated a new Roadmap to enable those goals. Called "Beyond Einstein", this Roadmap identifies three science objectives for the SEU theme: (1) Find out what powered the Big Bang; (2) Observe how black holes manipulate space, time, and matter; and (3) Identify the mysterious dark energy pullingthe Universe apart. These objectives can be realized through a combination of large observatories (Constellation-X, LISA), moderate sized, PI-led missions (the Einstein Probes), and a contuinuing program of technology development, research and analysis, and education/public outreach. In this presentation, NASA's proposed Beyond Einstein Program will be described. The full Roadmap is available at http://universe.nasa.gov/.

  16. The practical Einstein experiments, patents, inventions

    CERN Document Server

    Illy, József

    2012-01-01

    Albert Einstein may be best known as the wire-haired whacky physicist who gave us the theory of relativity, but that's just one facet of this genius' contribution to human knowledge and modern science. As Jozsef Illy expertly shows in this book, Einstein had an eminently practical side as well. As a youth, Einstein was an inveterate tinkerer in the electrical supply factory his father and uncle owned and operated. His first paid job was as a patent examiner. Later in life, Einstein contributed to many inventions, including refrigerators, microphones, and instruments for aviation. In published papers, Einstein often provided ways to test his theories and fundamental problems of the scientific community of his times. He delved deeply into a variety of technological innovations, most notably the gyrocompass, and consulted for industry in patent cases and on other legal matters. Einstein also provided explanations for common and mundane phenomena, such as the meandering of rivers. In these and other hands-on exam...

  17. Lifshitz black branes and DC transport coefficients in massive Einstein-Maxwell-dilaton gravity

    Science.gov (United States)

    Kuang, Xiao-Mei; Papantonopoulos, Eleftherios; Wu, Jian-Pin; Zhou, Zhenhua

    2018-03-01

    We construct analytical Lifshitz massive black brane solutions in massive Einstein-Maxwell-dilaton gravity theory. We also study the thermodynamics of these black brane solutions and obtain the thermodynamical stability conditions. On the dual nonrelativistic boundary field theory with Lifshitz symmetry, we analytically compute the DC transport coefficients, including the electric conductivity, thermoelectric conductivity, and thermal conductivity. The novel property of our model is that the massive term supports the Lifshitz black brane solutions with z ≠1 in such a way that the DC transport coefficients in the dual field theory are finite. We also find that the Wiedemann-Franz law in this dual boundary field theory is violated, which indicates that it may involve strong interactions.

  18. Can violations of Bell's inequalities be considered as a final proof of quantum physics?

    Science.gov (United States)

    Hénault, François

    2013-10-01

    Nowadays, it is commonly admitted that the experimental violation of Bell's inequalities that was successfully demonstrated in the last decades by many experimenters, are indeed the ultimate proof of quantum physics and of its ability to describe the whole microscopic world and beyond. But the historical and scientific story may not be envisioned so clearly: it starts with the original paper of Einstein, Podolsky and Rosen (EPR) aiming at demonstrating that the formalism of quantum theory is incomplete. It then goes through the works of D. Bohm, to finally proceed to the famous John Bell's relationships providing an experimental setup to solve the EPR paradox. In this communication is proposed an alternative reading of this history, showing that modern experiments based on correlations between light polarizations significantly deviate from the original spirit of the EPR paper. It is concluded that current experimental violations of Bell's inequalities cannot be considered as an ultimate proof of the completeness of quantum physics models.

  19. Einstein's Revolutionary Light-Quantum Hypothesis

    Science.gov (United States)

    Stuewer, Roger H.

    2005-05-01

    The paper in which Albert Einstein proposed his light-quantum hypothesis was the only one of his great papers of 1905 that he himself termed ``revolutionary.'' Contrary to widespread belief, Einstein did not propose his light-quantum hypothesis ``to explain the photoelectric effect.'' Instead, he based his argument for light quanta on the statistical interpretation of the second law of thermodynamics, with the photoelectric effect being only one of three phenomena that he offered as possible experimental support for it. I will discuss Einstein's light-quantum hypothesis of 1905 and his introduction of the wave-particle duality in 1909 and then turn to the reception of his work on light quanta by his contemporaries. We will examine the reasons that prominent physicists advanced to reject Einstein's light-quantum hypothesis in succeeding years. Those physicists included Robert A. Millikan, even though he provided convincing experimental proof of the validity of Einstein's equation of the photoelectric effect in 1915. The turning point came after Arthur Holly Compton discovered the Compton effect in late 1922, but even then Compton's discovery was contested both on experimental and on theoretical grounds. Niels Bohr, in particular, had never accepted the reality of light quanta and now, in 1924, proposed a theory, the Bohr-Kramers-Slater theory, which assumed that energy and momentum were conserved only statistically in microscopic interactions. Only after that theory was disproved experimentally in 1925 was Einstein's revolutionary light-quantum hypothesis generally accepted by physicists---a full two decades after Einstein had proposed it.

  20. Einstein Up in Smoke

    Science.gov (United States)

    Lisle, John

    2016-01-01

    Albert Einstein's biographers have not explained why he developed the abdominal aortic aneurysm that led to his death. Early conjectures proposed that it was caused by syphilis, without accurate evidence. The present article gives evidence to the contrary, and argues that the principal cause of Einstein's death was smoking.

  1. Experimental violation of a Bell's inequality with efficient detection.

    Science.gov (United States)

    Rowe, M A; Kielpinski, D; Meyer, V; Sackett, C A; Itano, W M; Monroe, C; Wineland, D J

    2001-02-15

    Local realism is the idea that objects have definite properties whether or not they are measured, and that measurements of these properties are not affected by events taking place sufficiently far away. Einstein, Podolsky and Rosen used these reasonable assumptions to conclude that quantum mechanics is incomplete. Starting in 1965, Bell and others constructed mathematical inequalities whereby experimental tests could distinguish between quantum mechanics and local realistic theories. Many experiments have since been done that are consistent with quantum mechanics and inconsistent with local realism. But these conclusions remain the subject of considerable interest and debate, and experiments are still being refined to overcome 'loopholes' that might allow a local realistic interpretation. Here we have measured correlations in the classical properties of massive entangled particles (9Be+ ions): these correlations violate a form of Bell's inequality. Our measured value of the appropriate Bell's 'signal' is 2.25 +/- 0.03, whereas a value of 2 is the maximum allowed by local realistic theories of nature. In contrast to previous measurements with massive particles, this violation of Bell's inequality was obtained by use of a complete set of measurements. Moreover, the high detection efficiency of our apparatus eliminates the so-called 'detection' loophole.

  2. Flooding Fragility Experiments and Prediction

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tahhan, Antonio [Idaho National Lab. (INL), Idaho Falls, ID (United States); Muchmore, Cody [Idaho National Lab. (INL), Idaho Falls, ID (United States); Nichols, Larinda [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bhandari, Bishwo [Idaho National Lab. (INL), Idaho Falls, ID (United States); Pope, Chad [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    This report describes the work that has been performed on flooding fragility, both the experimental tests being carried out and the probabilistic fragility predictive models being produced in order to use the text results. Flooding experiments involving full-scale doors have commenced in the Portal Evaluation Tank. The goal of these experiments is to develop a full-scale component flooding experiment protocol and to acquire data that can be used to create Bayesian regression models representing the fragility of these components. This work is in support of the Risk-Informed Safety Margin Characterization (RISMC) Pathway external hazards evaluation research and development.

  3. Radiating black holes in Einstein-Yang-Mills theory and cosmic censorship

    International Nuclear Information System (INIS)

    Ghosh, Sushant G.; Dadhich, Naresh

    2010-01-01

    Exact nonstatic spherically symmetric black-hole solutions of the higher dimensional Einstein-Yang-Mills equations for a null dust with Yang-Mills gauge charge are obtained by employing Wu-Yang ansatz, namely, HD-EYM Vaidya solution. It is interesting to note that gravitational contribution of Yang-Mills (YM) gauge charge for this ansatz is indeed opposite (attractive rather than repulsive) that of Maxwell charge. It turns out that the gravitational collapse of null dust with YM gauge charge admits strong curvature shell focusing naked singularities violating cosmic censorship. However, there is significant shrinkage of the initial data space for a naked singularity of the HD-Vaidya collapse due to presence of YM gauge charge. The effect of YM gauge charge on structure and location of the apparent and event horizons is also discussed.

  4. The Routledge guidebook to Einstein's relativity

    CERN Document Server

    Trefil, James

    2015-01-01

    Albert Einstein, one of the most prolific scientists of the twentieth century, developed the theory of relativity which was crucial for the advancement of modern physics. Young Einstein identified a paradox between Newtonian Mechanics and Maxwell's equations which pointed to a flawed understanding of space and time by the scientists of the day. In Relativity, Einstein presents his findings using a minimal amount of mathematical language, but the text can still be challenging for readers who lack an extensive scientific background.The Routledge Guidebook to Einstein's Relativity expands on and

  5. Einstein's cosmology review of 1933: a new perspective on the Einstein-de Sitter model of the cosmos

    Science.gov (United States)

    O'Raifeartaigh, Cormac; O'Keeffe, Michael; Nahm, Werner; Mitton, Simon

    2015-09-01

    We present a first English translation and analysis of a little-known review of relativistic cosmology written by Albert Einstein in late 1932. The article, which was published in 1933 in a book of Einstein papers translated into French, contains a substantial review of static and dynamic relativistic models of the cosmos, culminating in a discussion of the Einstein-de Sitter model. The article offers a valuable contemporaneous insight into Einstein's cosmology in the early 1930s and confirms that his interest lay in the development of the simplest model of the cosmos that could account for observation. The article also confirms that Einstein did not believe that simplified relativistic models could give an accurate description of the early universe.

  6. On the Coupling of Incompressible Stokes or Navier–Stokes and Darcy Flows Through Porous Media

    KAUST Repository

    Girault, V.; Kanschat, G.; Riviè re, B.

    2012-01-01

    In this chapter, we present the theoretical analysis of coupled incompressible Navier-Stokes (or Stokes) flows and Darcy flows with the Beavers-Joseph-Saffman interface condition. We discuss alternative interface and porous media models. We review

  7. Evaluation of micronozzle performance through DSMC, navier-stokes and coupled dsmc/navier-stokes approaches

    NARCIS (Netherlands)

    Torre, F. la; Kenjeres, S.; Kleijn, C.R.; Moerel, J.L.P.A.

    2009-01-01

    Both the particle based Direct Simulation Monte Carlo (DSMC) method and a compressible Navier-Stokes based continuum method are used to investigate the flow inside micronozzles and to predict the performance of such devices. For the Navier-Stokes approach, both slip and no-slip boundary conditions

  8. Universal Themes of Bose-Einstein Condensation

    Science.gov (United States)

    Proukakis, Nick P.; Snoke, David W.; Littlewood, Peter B.

    2017-04-01

    Foreword; List of contributors; Preface; Part I. Introduction: 1. Universality and Bose-Einstein condensation: perspectives on recent work D. W. Snoke, N. P. Proukakis, T. Giamarchi and P. B. Littlewood; 2. A history of Bose-Einstein condensation of atomic hydrogen T. Greytak and D. Kleppner; 3. Twenty years of atomic quantum gases: 1995-2015 W. Ketterle; 4. Introduction to polariton condensation P. B. Littlewood and A. Edelman; Part II. General Topics: Editorial notes; 5. The question of spontaneous symmetry breaking in condensates D. W. Snoke and A. J. Daley; 6. Effects of interactions on Bose-Einstein condensation R. P. Smith; 7. Formation of Bose-Einstein condensates M. J. Davis, T. M. Wright, T. Gasenzer, S. A. Gardiner and N. P. Proukakis; 8. Quenches, relaxation and pre-thermalization in an isolated quantum system T. Langen and J. Schmiedmayer; 9. Ultracold gases with intrinsic scale invariance C. Chin; 10. Berezinskii-Kosterlitz-Thouless phase of a driven-dissipative condensate N. Y. Kim, W. H. Nitsche and Y. Yamamoto; 11. Superfluidity and phase correlations of driven dissipative condensates J. Keeling, L. M. Sieberer, E. Altman, L. Chen, S. Diehl and J. Toner; 12. BEC to BCS crossover from superconductors to polaritons A. Edelman and P. B. Littlewood; Part III. Condensates in Atomic Physics: Editorial notes; 13. Probing and controlling strongly correlated quantum many-body systems using ultracold quantum gases I. Bloch; 14. Preparing and probing chern bands with cold atoms N. Goldman, N. R. Cooper and J. Dalibard; 15. Bose-Einstein condensates in artificial gauge fields L. J. LeBlanc and I. B. Spielman; 16. Second sound in ultracold atomic gases L. Pitaevskii and S. Stringari; 17. Quantum turbulence in atomic Bose-Einstein condensates N. G. Parker, A. J. Allen, C. F. Barenghi and N. P. Proukakis; 18. Spinor-dipolar aspects of Bose-Einstein condensation M. Ueda; Part IV. Condensates in Condensed Matter Physics: Editorial notes; 19. Bose-Einstein

  9. The Einstein tensor characterizing some Riemann spaces

    International Nuclear Information System (INIS)

    Rahman, M.S.

    1993-07-01

    A formal definition of the Einstein tensor is given. Mention is made of how this tensor plays a role of expressing certain conditions in a precise form. The cases of reducing the Einstein tensor to a zero tensor are studied on its merit. A lucid account of results, formulated as theorems, on Einstein symmetric and Einstein recurrent spaces is then presented. (author). 5 refs

  10. A one-to-one correspondence between the static Einstein-Maxwell and stationary Einstein-vacuum space-times

    International Nuclear Information System (INIS)

    Chandrasekhar, Subrahmanyan

    1989-01-01

    A one-to-one correspondence is established between the static solutions of the Einstein-Maxwell equations and the stationary solutions of the Einstein-vacuum equations, that enables one to directly write down a solution for the one from a known solution of the other, and conversely, by a simple transcription. The directness of the correspondence is achieved by writing the metric for static Einstein-Maxwell space-times in a coordinate system and a gauge adapted to the two-centre problem and the metric for stationary Einstein-vacuum space-times in a coordinate system and a gauge adapted to black holes with event horizons. (author)

  11. Einstein A to Z

    CERN Document Server

    Fox, Karen C

    2004-01-01

    Einstein was the twentieth century's most celebrated scientist - a man who developed the theory of relativity, revolutionised physics and became an iconic genius in the popular imagination. Essays range from the reasonably scientific including the theory of relativity, to the odd and engaging, such as Einstein's brain, his favourite jokes and films.

  12. Fragile X-associated disorders: Don't miss them.

    Science.gov (United States)

    Birch, Rachael C; Cohen, Jonathan; Trollor, Julian N

    2017-01-01

    Fragile X-associated disorders are a family of inherited disorders caused by expansions in the Fragile X Mental Retardation 1 (FMR1) gene. Premutation expansions of the FMR1 gene confer risk for fragile X-associated primary ovarian insufficiency and fragile X-associated tremor ataxia syndrome, as well as other medical and psychiatric comorbidities. Premutation expansions of the FMR1 gene are common in the general population. However, fragile X-associated disorders are frequently under-recognised and often misdiagnosed. The aim of this article is to describe fragile X-associated disorders and identify specific considerations for general practitioners (GPs) during identification and management of these disorders. GPs have a critical role in the identification of fragile X-associated disorders, as well as coordination of complex care needs. Prompt recognition and appropriate management of these disorders and potential medical and psychiatric comorbidities will have important implications not only for the affected patient, but also other family members who may be at risk.

  13. Component fragilities - data collection, analysis and interpretation

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1986-01-01

    As part of the component fragility research program sponsored by the US Nuclear Regulatory Commission, BNL is involved in establishing seismic fragility levels for various nuclear power plant equipment with emphasis on electrical equipment, by identifying, collecting and analyzing existing test data from various sources. BNL has reviewed approximately seventy test reports to collect fragility or high level test data for switchgears, motor control centers and similar electrical cabinets, valve actuators and numerous electrical and control devices of various manufacturers and models. Through a cooperative agreement, BNL has also obtained test data from EPRI/ANCO. An analysis of the collected data reveals that fragility levels can best be described by a group of curves corresponding to various failure modes. The lower bound curve indicates the initiation of malfunctioning or structural damage, whereas the upper bound curve corresponds to overall failure of the equipment based on known failure modes occurring separately or interactively. For some components, the upper and lower bound fragility levels are observed to vary appreciably depending upon the manufacturers and models. An extensive amount of additional fragility or high level test data exists. If completely collected and properly analyzed, the entire data bank is expected to greatly reduce the need for additional testing to establish fragility levels for most equipment

  14. Physics before and after Einstein

    CERN Document Server

    Capria, M Mamone

    2005-01-01

    It is now a century ago that one of the icons of modern physics published some of the most influential scientific papers of all times. With his work on relativity and quantum theory, Albert Einstein has altered the field of physics forever. It should not come as a surprise that looking back at Einstein''s work, one needs to rethink the whole scope of physics, before and after his time. This books aims to provide a perspective on the history of modern physics, spanning from the late 19th century up to today. It is not an encyclopaedic work, but it presents the groundbreaking and sometimes provocative main contributions by Einstein as marking the line between ''old'' and ''new'' physics, and expands on some of the developments and open issues to which they gave rise.

  15. Intrinsic character of Stokes matrices

    Science.gov (United States)

    Gagnon, Jean-François; Rousseau, Christiane

    2017-02-01

    Two germs of linear analytic differential systems x k + 1Y‧ = A (x) Y with a non-resonant irregular singularity are analytically equivalent if and only if they have the same eigenvalues and equivalent collections of Stokes matrices. The Stokes matrices are the transition matrices between sectors on which the system is analytically equivalent to its formal normal form. Each sector contains exactly one separating ray for each pair of eigenvalues. A rotation in S allows supposing that R+ lies in the intersection of two sectors. Reordering of the coordinates of Y allows ordering the real parts of the eigenvalues, thus yielding triangular Stokes matrices. However, the choice of the rotation in x is not canonical. In this paper we establish how the collection of Stokes matrices depends on this rotation, and hence on a chosen order of the projection of the eigenvalues on a line through the origin.

  16. Component fragility research program

    International Nuclear Information System (INIS)

    Tsai, N.C.; Mochizuki, G.L.; Holman, G.S.

    1989-11-01

    To demonstrate how ''high-level'' qualification test data can be used to estimate the ultimate seismic capacity of nuclear power plant equipment, we assessed in detail various electrical components tested by the Pacific Gas ampersand Electric Company for its Diablo Canyon plant. As part of our Phase I Component Fragility Research Program, we evaluated seismic fragility for five Diablo Canyon components: medium-voltage (4kV) switchgear; safeguard relay board; emergency light battery pack; potential transformer; and station battery and racks. This report discusses our Phase II fragility evaluation of a single Westinghouse Type W motor control center column, a fan cooler motor controller, and three local starters at the Diablo Canyon nuclear power plant. These components were seismically qualified by means of biaxial random motion tests on a shaker table, and the test response spectra formed the basis for the estimate of the seismic capacity of the components. The seismic capacity of each component is referenced to the zero period acceleration (ZPA) and, in our Phase II study only, to the average spectral acceleration (ASA) of the motion at its base. For the motor control center, the seismic capacity was compared to the capacity of a Westinghouse Five-Star MCC subjected to actual fragility tests by LLNL during the Phase I Component Fragility Research Program, and to generic capacities developed by the Brookhaven National Laboratory for motor control center. Except for the medium-voltage switchgear, all of the components considered in both our Phase I and Phase II evaluations were qualified in their standard commercial configurations or with only relatively minor modifications such as top bracing of cabinets. 8 refs., 67 figs., 7 tabs

  17. Einstein boundary conditions in relation to constraint propagation for the initial-boundary value problem of the Einstein equations

    International Nuclear Information System (INIS)

    Frittelli, Simonetta; Gomez, Roberto

    2004-01-01

    We show how the use of the normal projection of the Einstein tensor as a set of boundary conditions relates to the propagation of the constraints, for two representations of the Einstein equations with vanishing shift vector: the Arnowitt-Deser-Misner formulation, which is ill posed, and the Einstein-Christoffel formulation, which is symmetric hyperbolic. Essentially, the components of the normal projection of the Einstein tensor that act as nontrivial boundary conditions are linear combinations of the evolution equations with the constraints that are not preserved at the boundary, in both cases. In the process, the relationship of the normal projection of the Einstein tensor to the recently introduced 'constraint-preserving' boundary conditions becomes apparent

  18. Unified Maxwell-Einstein and Yang-Mills-Einstein supergravity theories in five dimensions

    International Nuclear Information System (INIS)

    Guenaydin, Murat; Zagermann, Marco

    2003-01-01

    Unified N = 2 Maxwell-Einstein supergravity theories (MESGTs) are supergravity theories in which all the vector fields, including the graviphoton, transform in an irreducible representation of a simple global symmetry group of the Lagrangian. As was established long time ago, in five dimensions there exist only four unified Maxwell-Einstein supergravity theories whose target manifolds are symmetric spaces. These theories are defined by the four simple euclidean Jordan algebras of degree three. In this paper, we show that, in addition to these four unified MESGTs with symmetric target spaces, there exist three infinite families of unified MESGTs as well as another exceptional one. These novel unified MESGTs are defined by non-compact (minkowskian) Jordan algebras, and their target spaces are in general neither symmetric nor homogeneous. The members of one of these three infinite families can be gauged in such a way as to obtain an infinite family of unified N = 2 Yang-Mills-Einstein supergravity theories, in which all vector fields transform in the adjoint representation of a simple gauge group of the type SU(N,1). The corresponding gaugings in the other two infinite families lead to Yang-Mills-Einstein supergravity theories coupled to tensor multiplets. (author)

  19. Seismic component fragility data base for IPEEE

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.; Hofmayer, C.

    1990-01-01

    Seismic probabilistic risk assessment or a seismic margin study will require a reliable data base of seismic fragility of various equipment classes. Brookhaven National Laboratory (BNL) has selected a group of equipment and generically evaluated the seismic fragility of each equipment class by use of existing test data. This paper briefly discusses the evaluation methodology and the fragility results. The fragility analysis results when used in the Individual Plant Examination for External Events (IPEEE) Program for nuclear power plants are expected to provide insights into seismic vulnerabilities of equipment for earthquakes beyond the design basis. 3 refs., 1 fig., 1 tab

  20. Einstein's cosmos how Albert Einstein's vision transformed our understanding of space and time

    CERN Document Server

    Kaku, Michio

    2004-01-01

    Few figures loom as large as Albert Einstein in our contemporary culture. It is truly remarkable that a man from such humble beginnings, an unemployed dreamer without a future or a job, who was written off by his professors as a hopeless loser, could to dare to scale the heights he reached. In this enlightening book Michio Kaku reasseses Einstein's work by centering on his three great theories - special relativity, general relativity and the Unified Field Theory. The first yielded the equation E =mc which is now such a fixture in our culture that it is practically a ubiquitous slogan. But the subsequent theories led to the Big Bang theory and have changed irrevocably the way we perceive time and space. Michio Kaku gives a new, refreshing look at the pioneering work of Einstein, giving a more accurate portrayal of his enduring legacy than previous biographies. As today's advanced physicists continue their intense search to fulfill Einstein's most cherished dream, a 'theory of everything', he is recognised as a...

  1. The NASA Beyond Einstein Program

    Science.gov (United States)

    White, Nicholas E.

    2006-01-01

    Einstein's legacy is incomplete, his theory of General relativity raises -- but cannot answer --three profound questions: What powered the big bang? What happens to space, time, and matter at the edge of a black hole? and What is the mysterious dark energy pulling the Universe apart? The Beyond Einstein program within NASA's Office of Space Science aims to answer these questions, employing a series of missions linked by powerful new technologies and complementary approaches towards shared science goals. The Beyond Einstein program has three linked elements which advance science and technology towards two visions; to detect directly gravitational wave signals from the earliest possible moments of the BIg Bang, and to image the event horizon of a black hole. The central element is a pair of Einstein Great Observatories, Constellation-X and LISA. Constellation-X is a powerful new X-ray observatory dedicated to X-Ray Spectroscopy. LISA is the first spaced based gravitational wave detector. These powerful facilities will blaze new paths to the questions about black holes, the Big Bang and dark energy. The second element is a series of competitively selected Einstein Probes, each focused on one of the science questions and includes a mission dedicated resolving the Dark Energy mystery. The third element is a program of technology development, theoretical studies and education. The Beyond Einstein program is a new element in the proposed NASA budget for 2004. This talk will give an overview of the program and the missions contained within it.

  2. MUS81 promotes common fragile site expression

    DEFF Research Database (Denmark)

    Ying, Songmin; Minocherhomji, Sheroy; Chan, Kok Lung

    2013-01-01

    Fragile sites are chromosomal loci with a propensity to form gaps or breaks during early mitosis, and their instability is implicated as being causative in certain neurological disorders and cancers. Recent work has demonstrated that the so-called common fragile sites (CFSs) often impair the fait......Fragile sites are chromosomal loci with a propensity to form gaps or breaks during early mitosis, and their instability is implicated as being causative in certain neurological disorders and cancers. Recent work has demonstrated that the so-called common fragile sites (CFSs) often impair...... the faithful disjunction of sister chromatids in mitosis. However, the mechanisms by which CFSs express their fragility, and the cellular factors required to suppress CFS instability, remain largely undefined. Here, we report that the DNA structure-specific nuclease MUS81-EME1 localizes to CFS loci in early...

  3. Einstein a hundred years of relativity

    CERN Document Server

    Robinson, Andrew

    2015-01-01

    "The eternal mystery of the world is its comprehensibility … The fact that it is comprehensible is a miracle." --Albert Einstein, 1936 Albert Einstein's universal appeal is only partially explained by his brilliant work in physics, as Andrew Robinson demonstrates in this authoritative, accessible, and richly illustrated biography. The main narrative is enriched by twelve essays by well-known scientists, scholars, and artists, including three Nobel Laureates. The book presents clearly the beautiful simplicity at the heart of Einstein's greatest discoveries, and explains how his ideas have continued to influence scientific developments such as lasers, the theory of the big bang, and "theories of everything." Einstein's life and activities outside of science are also considered, including his encounters with famous contemporaries such as Chaplin, Roosevelt, and Tagore, his love of music, and his troubled family life. The book recognizes that Einstein's striking originality was expressed in many ways, from hi...

  4. Conversations With Albert Einstein. II

    Science.gov (United States)

    Shankland, R. S.

    1973-01-01

    Discusses Einstein's views on the role of Michelson-Morley, Fizeau, and Miller experiments in the development of relativity and his attitude toward the theories of new quantum mechanics. Indicates that Einstein's opposition to quantum mechanics is beyond dispute. (CC)

  5. Albert Einstein Centenary

    CERN Document Server

    Amati, Daniele; Weisskopf, Victor Frederick; CERN. Geneva

    1979-01-01

    The scientist and his work by D. AMATI and S. FUBINI. A socially engaged scientist by V. F. WEISSKOPF. This week, we pay homage to Albert Einstein, the giant of twentieth-century physics born exactly 100 years ago on 14 March 1879 in Ulm, Germany. At the height of his career, Einstein made a whole series of monumental contributions to physics, including the elaborate theories of special and general relativity which revolutionized human thought and marked a major breakthrough in our understanding to the Universe. Along with quantum mechanics, relativity is one of the twin pillars of understanding which allow us here at CERN to study the behaviour of the tiniest components of matter. The development of quantum mechanics took the combined efforts of some of the greatest scientists the world has known, while relativity was developed almost single-handed by Einstein. The centenary of his birth is being commemorated all over the world. Exhibitions and symposia are being organized, books published, postage stamps is...

  6. Boltzmann, Einstein, Natural Law and Evolution

    International Nuclear Information System (INIS)

    Broda, E.

    1980-01-01

    Like Boltzmann, Einstein was a protagonist of atomistics. As a physicist, he has been called Boltzmann's true successor. Also in epistemology, after overcoming the positivist influence of Mach, Einstein approached Boltzmann. Any difference between Boltzmann's realism, or even materialism, and Einstein's pantheism may be merely a matter of emphasis. Yet a real difference exists in another respect. Boltzmann explained man's power of thinking and feeling, his morality and his esthetic sense, on an evolutionary, Darwinian, basis. In contrast, evolution had no role in Einstein's thought, though Darwin was accepted by him. This lack of appreciation of the importance of evolution is now attributed to socio-political factors. (author)

  7. Loophole-free Einstein-Podolsky-Rosen experiment via quantum steering

    International Nuclear Information System (INIS)

    Wittmann, Bernhard; Ramelow, Sven; Zeilinger, Anton; Steinlechner, Fabian; Langford, Nathan K; Ursin, Rupert; Brunner, Nicolas; Wiseman, Howard M

    2012-01-01

    Tests of the predictions of quantum mechanics for entangled systems have provided increasing evidence against local realistic theories. However, there remains the crucial challenge of simultaneously closing all major loopholes—the locality, freedom-of-choice and detection loopholes—in a single experiment. An important sub-class of local realistic theories can be tested with the concept of ‘steering’. The term ‘steering’ was introduced by Schrödinger in 1935 for the fact that entanglement would seem to allow an experimenter to remotely steer the state of a distant system as in the Einstein-Podolsky-Rosen (EPR) argument. Einstein called this ‘spooky action at a distance’. EPR-steering has recently been rigorously formulated as a quantum information task opening it up to new experimental tests. Here, we present the first loophole-free demonstration of EPR-steering by violating three-setting quadratic steering inequality, tested with polarization-entangled photons shared between two distant laboratories. Our experiment demonstrates this effect while simultaneously closing all loopholes: both the locality loophole and a specific form of the freedom-of-choice loophole are closed by having a large separation of the parties and using fast quantum random number generators, and the fair-sampling loophole is closed by having high overall detection efficiency. Thereby, we exclude—for the first time loophole-free—an important class of local realistic theories considered by EPR. Besides its foundational importance, loophole-free steering also allows the distribution of quantum entanglement secure event in the presence of an untrusted party. (paper)

  8. Loophole-free Einstein-Podolsky-Rosen experiment via quantum steering

    Science.gov (United States)

    Wittmann, Bernhard; Ramelow, Sven; Steinlechner, Fabian; Langford, Nathan K.; Brunner, Nicolas; Wiseman, Howard M.; Ursin, Rupert; Zeilinger, Anton

    2012-05-01

    Tests of the predictions of quantum mechanics for entangled systems have provided increasing evidence against local realistic theories. However, there remains the crucial challenge of simultaneously closing all major loopholes—the locality, freedom-of-choice and detection loopholes—in a single experiment. An important sub-class of local realistic theories can be tested with the concept of ‘steering’. The term ‘steering’ was introduced by Schrödinger in 1935 for the fact that entanglement would seem to allow an experimenter to remotely steer the state of a distant system as in the Einstein-Podolsky-Rosen (EPR) argument. Einstein called this ‘spooky action at a distance’. EPR-steering has recently been rigorously formulated as a quantum information task opening it up to new experimental tests. Here, we present the first loophole-free demonstration of EPR-steering by violating three-setting quadratic steering inequality, tested with polarization-entangled photons shared between two distant laboratories. Our experiment demonstrates this effect while simultaneously closing all loopholes: both the locality loophole and a specific form of the freedom-of-choice loophole are closed by having a large separation of the parties and using fast quantum random number generators, and the fair-sampling loophole is closed by having high overall detection efficiency. Thereby, we exclude—for the first time loophole-free—an important class of local realistic theories considered by EPR. Besides its foundational importance, loophole-free steering also allows the distribution of quantum entanglement secure event in the presence of an untrusted party.

  9. Exact solutions of Einstein and Einstein-Maxwell equations in higher-dimensional spacetime

    International Nuclear Information System (INIS)

    Xu Dianyan; Beijing Univ., BJ

    1988-01-01

    The D-dimensional Schwarzschild-de Sitter metric and Reissner-Nordstrom-de-Sitter metric are derived directly by solving the Einstein and Einstein-Maxwell equations. The D-dimensional Kerr metric is rederived by using the complex coordinate transformation method and the D-dimensional Kerr-de Sitter metric is also given. The conjecture about the D-dimensional metric of a rotating charged mass is given at the end of this paper. (author)

  10. When Art Meets Einstein

    Science.gov (United States)

    Science Scope, 2006

    2006-01-01

    This article deals with a pale blue sculpture entitled "A New World View", as an homage to the most famous scientist in modern history, Albert Einstein. It has 32 bas-relief squares composed of glass and steel that represent one aspect of the life and legacy of Albert Einstein. Images of children's faces peer out from behind the glass squares,…

  11. Albert Einstein memorial lectures

    CERN Document Server

    Mechoulam, Raphael; The Israel Academy for Sciences and Humanities

    2012-01-01

    This volume consists of a selection of the Albert Einstein Memorial Lectures presented annually at the Israel Academy of Sciences and Humanities. Delivered by eminent scientists and scholars, including Nobel laureates, they cover a broad spectrum of subjects in physics, chemistry, life science, mathematics, historiography and social issues. This distinguished memorial lecture series was inaugurated by the Israel Academy of Sciences and Humanities following an international symposium held in Jerusalem in March 1979 to commemorate the centenary of Albert Einstein's birth. Considering that Einstein's interests, activities and influence were not restricted to theoretical physics but spanned broad fields affecting society and the welfare of humankind, it was felt that these memorial lectures should be addressed to scientists, scholars and erudite laypersons rather than to physicists alone.

  12. Astrophysical observations: lensing and eclipsing Einstein's theories.

    Science.gov (United States)

    Bennett, Charles L

    2005-02-11

    Albert Einstein postulated the equivalence of energy and mass, developed the theory of special relativity, explained the photoelectric effect, and described Brownian motion in five papers, all published in 1905, 100 years ago. With these papers, Einstein provided the framework for understanding modern astrophysical phenomena. Conversely, astrophysical observations provide one of the most effective means for testing Einstein's theories. Here, I review astrophysical advances precipitated by Einstein's insights, including gravitational redshifts, gravitational lensing, gravitational waves, the Lense-Thirring effect, and modern cosmology. A complete understanding of cosmology, from the earliest moments to the ultimate fate of the universe, will require developments in physics beyond Einstein, to a unified theory of gravity and quantum physics.

  13. Approximate Stokes Drift Profiles in Deep Water

    Science.gov (United States)

    Breivik, Øyvind; Janssen, Peter A. E. M.; Bidlot, Jean-Raymond

    2014-09-01

    A deep-water approximation to the Stokes drift velocity profile is explored as an alternative to the monochromatic profile. The alternative profile investigated relies on the same two quantities required for the monochromatic profile, viz the Stokes transport and the surface Stokes drift velocity. Comparisons with parametric spectra and profiles under wave spectra from the ERA-Interim reanalysis and buoy observations reveal much better agreement than the monochromatic profile even for complex sea states. That the profile gives a closer match and a more correct shear has implications for ocean circulation models since the Coriolis-Stokes force depends on the magnitude and direction of the Stokes drift profile and Langmuir turbulence parameterizations depend sensitively on the shear of the profile. The alternative profile comes at no added numerical cost compared to the monochromatic profile.

  14. Einstein before Israel Zionist icon or iconoclast?

    CERN Document Server

    Rosenkranz, Ze’ev

    2011-01-01

    Albert Einstein was initially skeptical and even disdainful of the Zionist movement, yet he affiliated himself with this controversial political ideology and today is widely seen as an outspoken advocate for a modern Jewish homeland in Palestine. What enticed this renowned scientist and humanitarian, who repeatedly condemned nationalism of all forms, to radically change his views? Was he in fact a Zionist? Einstein Before Israel traces Einstein's involvement with Zionism from his initial contacts with the movement at the end of World War I to his emigration from Germany in 1933 in the wake of Hitler's rise to power. Drawing on a wealth of rare archival evidence--much of it never before published--this book offers the most nuanced picture yet of Einstein's complex and sometimes stormy relationship with Jewish nationalism. Ze'ev Rosenkranz sheds new light on Einstein's encounters with prominent Zionist leaders, and reveals exactly what Einstein did and didn't like about Zionist beliefs, objectives, and methods...

  15. On solutions of Einstein and Einstein-Yang-Mills equations with (maximal) conformal subsymmetries

    International Nuclear Information System (INIS)

    Sinzinkayo, S.; Demaret, J.

    1985-01-01

    The maximal subgroups of the conformal group (which have in common as a subgroup the group of pure spatial rotations) are considered as isometry groups of conformally flat space-times. The corresponding cosmological solutions of Einstein's field equations are identified. For each of them, the possibility is investigated that it could be generated by an SU(2) Yang-Mills field built, via the Corrigan-Fairlie-'t Hooft-Wilczek ansatz, from a scalar field identical with the square root of the conformal factor defining the space-time metric tensor. In particular, the Einstein cosmological model can be generated in this manner, but in the framework of strong gravity only, a micro-Einstein universe being then viewed as a possible model for a hadron. (author)

  16. Vortex sorter for Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Whyte, Graeme; Veitch, John; Courtial, Johannes; Oehberg, Patrik

    2004-01-01

    We have designed interferometers that sort Bose-Einstein condensates into their vortex components. The Bose-Einstein condensates in the two arms of the interferometer are rotated with respect to each other through fixed angles; different vortex components then exit the interferometer in different directions. The method we use to rotate the Bose-Einstein condensates involves asymmetric phase imprinting and is itself new. We have modeled rotation through fixed angles and sorting into vortex components with even and odd values of the topological charge of two-dimensional Bose-Einstein condensates in a number of states (pure or superposition vortex states for different values of the scattering length). Our scheme may have applications for quantum information processing

  17. Lorentz invariance violation and charge (non)conservation: A general theoretical frame for extensions of the Maxwell equations

    International Nuclear Information System (INIS)

    Laemmerzahl, Claus; Macias, Alfredo; Mueller, Holger

    2005-01-01

    All quantum gravity approaches lead to small modifications in the standard laws of physics which in most cases lead to violations of Lorentz invariance. One particular example is the extended standard model (SME). Here, a general phenomenological approach for extensions of the Maxwell equations is presented which turns out to be more general than the SME and which covers charge nonconservation (CNC), too. The new Lorentz invariance violating terms cannot be probed by optical experiments but need, instead, the exploration of the electromagnetic field created by a point charge or a magnetic dipole. Some scalar tensor theories and higher dimensional brane theories predict CNC in four dimensions and some models violating special relativity have been shown to be connected with CNC. Its relation to the Einstein Equivalence Principle has been discussed. Because of this upcoming interest, the experimental status of electric charge conservation is reviewed. Up to now there seem to exist no unique tests of charge conservation. CNC is related to the precession of polarization, to a modification of the 1/r-Coulomb potential, and to a time dependence of the fine structure constant. This gives the opportunity to describe a dedicated search for CNC

  18. CP violation

    CERN Document Server

    1989-01-01

    Contents: CP Phenomenology: Introduction to CP Violation (C Jarlskog); CP-Violation in the K 0 -K 0 -System (K Kleinknecht); The Quark Mixing Matrix, Charm Decays and B Decays (S Stone); The Question of CP Noninvariance - As Seen through the Eyes of Neutral Beauty (I I Bigi et al.); In Search of CP Noninvariance in Heavy Quark Systems (L-L Chau); CP Violation at High Energy e + e - Colliders (J Bernabéu & M B Gavela); CP Violation in the Standard Model with Four Families (A Datta & E A Paschos); CP Effects When Neutrinos are their Own Antiparticles (B Kayser); On Spontaneous CP Violation Trigg

  19. On the Coupling of Incompressible Stokes or Navier–Stokes and Darcy Flows Through Porous Media

    KAUST Repository

    Girault, V.

    2012-11-03

    In this chapter, we present the theoretical analysis of coupled incompressible Navier-Stokes (or Stokes) flows and Darcy flows with the Beavers-Joseph-Saffman interface condition. We discuss alternative interface and porous media models. We review some finite element methods used by several authors in this coupling and present numerical experiments.

  20. Einstein's Jury The Race to Test Relativity

    CERN Document Server

    Crelinsten, Jeffrey

    2006-01-01

    Einstein's Jury is the dramatic story of how astronomers in Germany, England, and America competed to test Einstein's developing theory of relativity. Weaving a rich narrative based on extensive archival research, Jeffrey Crelinsten shows how these early scientific debates shaped cultural attitudes we hold today. The book examines Einstein's theory of general relativity through the eyes of astronomers, many of whom were not convinced of the legitimacy of Einstein's startling breakthrough. These were individuals with international reputations to uphold and benefactors and shareholders to p

  1. Piecewise linear manifolds: Einstein metrics and Ricci flows

    International Nuclear Information System (INIS)

    Schrader, Robert

    2016-01-01

    This article provides an attempt to extend concepts from the theory of Riemannian manifolds to piecewise linear (p.l.) spaces. In particular we propose an analogue of the Ricci tensor, which we give the name of an Einstein vector field . On a given set of p.l. spaces we define and discuss (normalized) Einstein flows. p.l. Einstein metrics are defined and examples are provided. Criteria for flows to approach Einstein metrics are formulated. Second variations of the total scalar curvature at a specific Einstein space are calculated. (paper)

  2. Determinants of Banking System Fragility : A Regional Perspective

    NARCIS (Netherlands)

    Degryse, H.A.; Elahi, M.A.; Penas, M.F.

    2012-01-01

    Abstract: Banking systems are fragile not only within one country but also within and across regions. We study the role of regional banking system characteristics for regional banking system fragility. We find that regional banking system fragility reduces when banks in the region jointly hold more

  3. Two copies of the Einstein-Podolsky-Rosen state of light lead to refutation of EPR ideas.

    Science.gov (United States)

    Rosołek, Krzysztof; Stobińska, Magdalena; Wieśniak, Marcin; Żukowski, Marek

    2015-03-13

    Bell's theorem applies to the normalizable approximations of original Einstein-Podolsky-Rosen (EPR) state. The constructions of the proof require measurements difficult to perform, and dichotomic observables. By noticing the fact that the four mode squeezed vacuum state produced in type II down-conversion can be seen both as two copies of approximate EPR states, and also as a kind of polarization supersinglet, we show a straightforward way to test violations of the EPR concepts with direct use of their state. The observables involved are simply photon numbers at outputs of polarizing beam splitters. Suitable chained Bell inequalities are based on the geometric concept of distance. For a few settings they are potentially a new tool for quantum information applications, involving observables of a nondichotomic nature, and thus of higher informational capacity. In the limit of infinitely many settings we get a Greenberger-Horne-Zeilinger-type contradiction: EPR reasoning points to a correlation, while quantum prediction is an anticorrelation. Violations of the inequalities are fully resistant to multipair emissions in Bell experiments using parametric down-conversion sources.

  4. Employment Impact and Financial Burden for Families of Children with Fragile X Syndrome: Findings from the National Fragile X Survey

    Science.gov (United States)

    Ouyang, L.; Grosse, S.; Raspa, M.; Bailey, D.

    2010-01-01

    Background: The employment impact and financial burden experienced by families of children with fragile X syndrome (FXS) has not been quantified in the USA. Method: Using a national fragile X family survey, we analysed data on 1019 families with at least one child who had a full FXS mutation. Out-of-pocket expenditures related to fragile X were…

  5. Einstein's universe

    CERN Document Server

    Calder, Nigel

    1979-01-01

    This brilliantly written book unlocks the astounding implications of Einstein's revolutionary theories on the nature of science, time and motion. It far surpasses any previous explanation of Relativity for laymen.

  6. Financial fragility in the Great Moderation

    NARCIS (Netherlands)

    Bezemer, Dirk; Grydaki, Maria

    2014-01-01

    A nascent literature explores the measurement of financial fragility. This paper considers evidence for rising financial fragility during the 1984-2007 Great Moderation in the U.S. The literature suggests that macroeconomic stability combined with strong growth of credit to asset markets, in asset

  7. Solutions of Einstein's field equations

    Energy Technology Data Exchange (ETDEWEB)

    Tomonaga, Y [Utsunomiya Univ. (Japan). Faculty of Education

    1978-12-01

    In this paper the author investigates the Einstein's field equations of the non-vacuum case and generalizes the solution of Robertson-Walker by the three dimensional Einstein spaces. In Section 2 the author shortly generalizes the dynamic space-time of G. Lemetre and A. Friedmann by a simple transformation.

  8. Conceptual Development of Einstein's Mass-Energy Relationship

    Science.gov (United States)

    Wong, Chee Leong; Yap, Kueh Chin

    2005-01-01

    Einstein's special theory of relativity was published in 1905. It stands as one of the greatest intellectual achievements in the history of human thought. Einstein described the equivalence of mass and energy as "the most important upshot of the special theory of relativity" (Einstein, 1919). In this paper, we will discuss the evolution of the…

  9. Einstein for Schools and the General Public

    Science.gov (United States)

    Johansson, K. E.; Kozma, C; Nilsson, Ch

    2006-01-01

    In April 2005 the World Year of Physics (Einstein Year in the UK and Ireland) was celebrated with an Einstein week in Stockholm House of Science. Seven experiments illustrated Einstein's remarkable work in 1905 on Brownian motion, the photoelectric effect and special relativity. Thirteen school classes with 260 pupils, 30 teachers and 25 members…

  10. Series expansion of the modified Einstein Procedure

    Science.gov (United States)

    Seema Chandrakant Shah-Fairbank

    2009-01-01

    This study examines calculating total sediment discharge based on the Modified Einstein Procedure (MEP). A new procedure based on the Series Expansion of the Modified Einstein Procedure (SEMEP) has been developed. This procedure contains four main modifications to MEP. First, SEMEP solves the Einstein integrals quickly and accurately based on a series expansion. Next,...

  11. Mileva Maric Einstein vivre avec Albert Einstein

    CERN Document Server

    Milentijevic, Radmila

    2013-01-01

    Radmila Milentijevic n’est pas la première à écrire sur les relations entre le génial Albert Einstein et sa première épouse et précieuse collaboratrice durant ses années de recherches, la scientifique serbe Mileva Maric. Mais c’est la première fois qu’un ouvrage traite de cette idylle, puis de ce drame familial qui a duré près de cinquante années, sous une forme quasiment poétique, si rare dans l’historiographie scientifique.Professeur émérite d’histoire à l’université de New York, l’auteur propose ici une monographie riche et vivante, dévoilant une face cachée d’Albert Einstein, et faisant de sa compagne une figure historique de premier plan en même temps qu’un personnage romanesque dont le destin tragique ne laissera aucun lecteur indifférent.

  12. Stochastic 2-D Navier-Stokes Equation

    International Nuclear Information System (INIS)

    Menaldi, J.L.; Sritharan, S.S.

    2002-01-01

    In this paper we prove the existence and uniqueness of strong solutions for the stochastic Navier-Stokes equation in bounded and unbounded domains. These solutions are stochastic analogs of the classical Lions-Prodi solutions to the deterministic Navier-Stokes equation. Local monotonicity of the nonlinearity is exploited to obtain the solutions in a given probability space and this significantly improves the earlier techniques for obtaining strong solutions, which depended on pathwise solutions to the Navier-Stokes martingale problem where the probability space is also obtained as a part of the solution

  13. Stokes Space in Direct-Detection Data Transmission Systems

    DEFF Research Database (Denmark)

    Estaran Tolosa, Jose Manuel; Lu, Xiaofeng; Zibar, Darko

    2015-01-01

    Stokes-based processing permits complete and phase-insensitive characterization of the field’s SOP, readily unlocking polarization diversity in transmission systems where DD is desired. We present an overview on Stokes notions and most recent achievements in this context.......Stokes-based processing permits complete and phase-insensitive characterization of the field’s SOP, readily unlocking polarization diversity in transmission systems where DD is desired. We present an overview on Stokes notions and most recent achievements in this context....

  14. Chromosome fragility at FRAXA in human cleavage stage embryos at risk for fragile X syndrome.

    Science.gov (United States)

    Verdyck, Pieter; Berckmoes, Veerle; De Vos, Anick; Verpoest, Willem; Liebaers, Inge; Bonduelle, Maryse; De Rycke, Martine

    2015-10-01

    Fragile X syndrome (FXS), the most common inherited intellectual disability syndrome, is caused by expansion and hypermethylation of the CGG repeat in the 5' UTR of the FMR1 gene. This expanded repeat, also known as the rare fragile site FRAXA, causes X chromosome fragility in cultured cells from patients but only when induced by perturbing pyrimidine synthesis. We performed preimplantation genetic diagnosis (PGD) on 595 blastomeres biopsied from 442 cleavage stage embryos at risk for FXS using short tandem repeat (STR) markers. In six blastomeres, from five embryos an incomplete haplotype was observed with loss of all alleles telomeric to the CGG repeat. In all five embryos, the incomplete haplotype corresponded to the haplotype carrying the CGG repeat expansion. Subsequent analysis of additional blastomeres from three embryos by array comparative genomic hybridization (aCGH) confirmed the presence of a terminal deletion with a breakpoint close to the CGG repeat in two blastomeres from one embryo. A blastomere from another embryo showed the complementary duplication. We conclude that a CGG repeat expansion at FRAXA causes X chromosome fragility in early human IVF embryos at risk for FXS. © 2015 Wiley Periodicals, Inc.

  15. Einstein and the "Crucial" Experiment

    Science.gov (United States)

    Holton, Gerald

    1969-01-01

    Examines the widespread view that it was the crucial Michelson-Morley experiment that led Einstein to formulate the special relativity theory. From Einstein's writings, evidence is presented that no such direct genetic connection exists. The author suggests that the historian of science must resist the experimenticist's fallacy of imposing a…

  16. The fragile X syndrome: Isolation of the FMR-1 gene and characterization of the fragile X mutation

    NARCIS (Netherlands)

    B.A. Oostra (Ben); A. Verkerk

    1992-01-01

    markdownabstractConclusion Rapid progress has been made in the analysis of the fragile X syndrome during 1991. Different groups have discovered that fragile X chromosomes are preferentially methylated. In these X chromosomes an insertion has been found in the methylated region. The FMR-1 gene,

  17. 2011 Einstein Fellows Chosen

    Science.gov (United States)

    2011-03-01

    ASA has announced the selection of the 2011 Einstein Fellows who will conduct research related to NASA's Physics of the Cosmos program, which aims to expand our knowledge of the origin, evolution, and fate of the Universe. The Einstein Fellowship provides support to the awardees for three years, and the Fellows may pursue their research at a host university or research center of their choosing in the United States. The new Fellows will begin their programs in the fall of 2011. The new Einstein Fellows and their host institutions are listed below: * Akos Bogdan (Smithsonian Astrophysical Observatory, Cambridge, Mass.) * Samuel Gralla (University of Maryland, College Park, Md.) * Philip Hopkins (University of California at Berkeley) * Matthew Kunz (Princeton University, Princeton, N.J.) * Laura Lopez (Massachusetts Institute of Technology, Cambridge, Mass.) * Amy Reines (National Radio Astronomy Observatory, Charlottesville, Virg.) * Rubens Reis (University of Michigan, Ann Arbor) * Ken Shen (Lawrence Berkeley National Laboratory, Berkeley, Calif.) * Jennifer Siegal-Gaskins (California Institute of Technology, Pasadena) * Lorenzo Sironi (Harvard University, Cambridge, Mass.) NASA has two other astrophysics theme-based fellowship programs: the Sagan Fellowship Program, which supports research into exoplanet exploration, and the Hubble Fellowship Program, which supports research into cosmic origins. More information on the Einstein Fellowships can be found at: http://cxc.harvard.edu/fellows/

  18. Exact Solutions for Einstein's Hyperbolic Geometric Flow

    International Nuclear Information System (INIS)

    He Chunlei

    2008-01-01

    In this paper we investigate the Einstein's hyperbolic geometric flow and obtain some interesting exact solutions for this kind of flow. Many interesting properties of these exact solutions have also been analyzed and we believe that these properties of Einstein's hyperbolic geometric flow are very helpful to understanding the Einstein equations and the hyperbolic geometric flow

  19. Seismic fragility capacity of equipment

    International Nuclear Information System (INIS)

    Iijima, Toru; Abe, Hiroshi; Suzuki, Kenichi

    2006-01-01

    Seismic probabilistic safety assessment (PSA) is an available method to evaluate residual risks of nuclear plants that are designed on definitive seismic conditions. From our preliminary seismic PSA analysis, horizontal shaft pumps are important components that have significant influences on the core damage frequency (CDF). An actual horizontal shaft pump and some kinds of elements were tested to evaluate realistic fragility capacities. Our test results showed that the realistic fragility capacity of horizontal shaft pump would be at least four times as high as a current value, 1.6 x 9.8 m/s 2 , used for our seismic PSA. We are going to incorporate the fragility capacity data that were obtained from those tests into our seismic PSA analysis, and we expect that the reliability of seismic PSA should increase. (author)

  20. Quantum theory and Einstein's general relativity

    International Nuclear Information System (INIS)

    Borzeszkowski, H.H.v.; Treder, H.J.

    1984-01-01

    The paper concerns Einstein's general relativity, wave mechanics and the quantization of Einstein's gravitation equations. The principle of equivalence and its association with both wave mechanics and quantum gravity, is discussed. (U.K.)

  1. Seismic fragility analyses

    International Nuclear Information System (INIS)

    Kostov, Marin

    2000-01-01

    In the last two decades there is increasing number of probabilistic seismic risk assessments performed. The basic ideas of the procedure for performing a Probabilistic Safety Analysis (PSA) of critical structures (NUREG/CR-2300, 1983) could be used also for normal industrial and residential buildings, dams or other structures. The general formulation of the risk assessment procedure applied in this investigation is presented in Franzini, et al., 1984. The probability of failure of a structure for an expected lifetime (for example 50 years) can be obtained from the annual frequency of failure, β E determined by the relation: β E ∫[d[β(x)]/dx]P(flx)dx. β(x) is the annual frequency of exceedance of load level x (for example, the variable x may be peak ground acceleration), P(fI x) is the conditional probability of structure failure at a given seismic load level x. The problem leads to the assessment of the seismic hazard β(x) and the fragility P(fl x). The seismic hazard curves are obtained by the probabilistic seismic hazard analysis. The fragility curves are obtained after the response of the structure is defined as probabilistic and its capacity and the associated uncertainties are assessed. Finally the fragility curves are combined with the seismic loading to estimate the frequency of failure for each critical scenario. The frequency of failure due to seismic event is presented by the scenario with the highest frequency. The tools usually applied for probabilistic safety analyses of critical structures could relatively easily be adopted to ordinary structures. The key problems are the seismic hazard definitions and the fragility analyses. The fragility could be derived either based on scaling procedures or on the base of generation. Both approaches have been presented in the paper. After the seismic risk (in terms of failure probability) is assessed there are several approaches for risk reduction. Generally the methods could be classified in two groups. The

  2. Fragile X syndrome

    Science.gov (United States)

    ... problems, or intellectual disability may not be present. Symptoms Behavior problems associated with fragile X syndrome include: Autism spectrum disorder Delay in crawling, walking, or twisting Hand flapping ...

  3. The Detection and Analysis of Chromosome Fragile Sites

    DEFF Research Database (Denmark)

    Bjerregaard, Victoria A; Özer, Özgün; Hickson, Ian D

    2018-01-01

    A fragile site is a chromosomal locus that is prone to form a gap or constriction visible within a condensed metaphase chromosome, particularly following exposure of cells to DNA replication stress. Based on their frequency, fragile sites are classified as either common (CFSs; present in all...... for detection and analysis of chromosome fragile sites....

  4. The world-line. Albert Einstein and modern physics; Die Weltlinie. Albert Einstein und die moderne Physik

    Energy Technology Data Exchange (ETDEWEB)

    Maalampi, Jukka [Jyvaeskylae Univ. (Finland). Dept. of Physics

    2008-07-01

    This book is an entertaining and formula-free presentation of modern physics from the 19th century to present. The life of Albert Einstein and his scientific works are drawn as red fathom through the text. The author explains central terms and results of modern physics in populary-scientific form from the historical perspective. To the reader in humorous form an imagination is mediated how modern physics has been developed. We learn from the exciting effects of the ether, we hear from faraday and magnetic needles, from Maxwell's prediction of the electromagnetic waves, from heinrich Hertz and from the photoelectric effect. Was the Michelson-Morley experiment a measurement success or an unsuccess? Why has Einstein abandoned the ether? How has Einstein in the miraculous year 1905 revolutionated physics and why he has begged Newton for excusement? Exist atoms? What is motion? What is light and what is to be understood under ''now'' and ''here''? Light deviation or non-deviation? How act the tidal forces? And above all: How has Einstein answered these questions. We meet Poincare, Lorentz and Hilbert, Boltzmann and Bohr, Minkowski, Planck, de Broglie, Hubble and Weyl, Gamow, Hahn and Meitner, Kapiza and Landau, Fermi and many other famous scientists. What had Eddington against Chandrasekhar and what had Einstein against black holes? Why should space tourists and dream tourists make holiday not on the Loch Ness but on the safe side of a black hole? Why inveighed Pauli against Einstein? Is the concern with the atomic-bomb formula right? Smeared matter, big bang and cosmic background radiation, gravitational waves and double pulsars, the cosmological constant and the expansion of the universe are further themes, which keep the reader in breath and let no mental vacuum arise. [German] Das Buch ist eine unterhaltsame und formelfreie Darstellung der modernen Physik vom 19. Jahrhundert bis zur Gegenwart. Das Leben Albert Einsteins

  5. Origins of Stokes shift in PbS nanocrystals

    KAUST Repository

    Voznyy, Oleksandr

    2017-10-27

    Stokes shift, an energy difference between the excitonic absorption and emission, is a property of colloidal quantum dots (CQDs) typically ascribed to splitting between dark and bright excitons. In some materials, e.g., PbS, CuInS2, CdHgTe, a Stokes shift of up to 200 meV is observed, substantially larger than the estimates of dark-bright state splitting or vibronic relaxations. The shift origin remains highly debated, as contradictory signatures of both surface and bulk character were reported for the Stokes-shifted electronic state. Here we show that the energy transfer among CQDs in a polydispersed ensemble in solution suffices to explain the excess Stokes shift. This energy transfer is primarily due to CQD aggregation, and can be substantially eliminated by extreme dilution, higher-viscosity solvent, or better-dispersed colloids. Our findings highlight that ensemble polydispersity remains the primary source of the Stokes shift in CQDs in solution, propagating into the Stokes shift in films and the open-circuit voltage deficit in CQD solar cells. Improved synthetic control can bring notable advancements in CQD photovoltaics, and the Stokes shift continues to provide a sensitive and significant metric to monitor ensemble size distribution.

  6. Albert Einstein's Magic Mountain: An Aarau Education*

    Science.gov (United States)

    Hunziker, Herbert

    2015-03-01

    For economic reasons, the electrotechnical factory J. Einstein & Cie. (co-owned by Albert Einstein's father Hermann) had to be closed in the summer of 1894. While Albert's parents emigrated to Italy to build a new existence, he remained in Munich to complete his studies at the Gymnasium. Left behind, however, he had a difficult time with what he considered the rigid educational practices at the Munich Luitpold-Gymnasium and quit without a diploma. The present article discusses Einstein's richly winding path to the Aargau Cantonal School (Switzerland), especially its history and educational philosophy during the time of his stay in Aarau. There, Einstein met some outstanding teachers, who could serve him as models of scholars and human beings. In spite of Einstein's distinct independence of mind, these personalities may well have had a significant influence on the alignment of his inner compass.

  7. Albert Einstein: A Biographical Sketch

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 4. Albert Einstein: A Biographical Sketch. Maja Winteler-Einstein. Reflections Volume 5 Issue 4 April 2000 pp 111-120. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/005/04/0111-0120 ...

  8. Einstein's Materialism and Modern Tests of Quantum Mechanics

    Science.gov (United States)

    Vigier, J. P.

    After a presentation of Einstein's and Bohr's antagonistic point of view on the interpretation of Quantum Mechanics an illustration of their conflicting positions in the particular case of Young's double slit experiment is presented. It is then shown that in their most recent form (i. e. time dependent neutron interferometry) these experiments suggest (if one accepts absolute energymomentum conservation in all individual microprocesses) that Einstein was right in the Bohr-Einstein controversy.Translated AbstractEinsteins Materialismus und heutige Tests der QuantenmechanikNach einer Darstellung von Einsteins und Bohrs antagonistischen Standpunkten in der Interpretation der Quantenmechanik werden ihre widersprüchlichen Positionen im speziellen Fall des Youngschen Doppelspaltexperiments dargestellt. Es wird dann gezeigt, daß diese Experimente in ihrer neuesten Form (d. h. zeitabhängige Neutroneninterferometrie) Einstein in der Bohr-Einsteinkontroverse recht gaben (wenn man absolute Energie-Impulserhaltung bei allen individuellen Mikroprozessen annimmt).

  9. Revisiting Einstein's brain in Brain Awareness Week.

    Science.gov (United States)

    Chen, Hao; Chen, Su; Zeng, Lidan; Zhou, Lin; Hou, Shengtao

    2014-10-01

    Albert Einstein's brain has long been an object of fascination to both neuroscience specialists and the general public. However, without records of advanced neuro-imaging of his brain, conclusions regarding Einstein's extraordinary cognitive capabilities can only be drawn based on the unique external features of his brain and through comparison of the external features with those of other human brain samples. The recent discovery of 14 previously unpublished photographs of Einstein's brain taken at unconventional angles by Dr. Thomas Stoltz Harvey, the pathologist, ignited a renewed frenzy about clues to explain Einstein's genius. Dr. Dean Falk and her colleagues, in their landmark paper published in Brain (2013; 136:1304-1327), described in such details about the unusual features of Einstein's brain, which shed new light on Einstein's intelligence. In this article, we ask what are the unique structures of his brain? What can we learn from this new information? Can we really explain his extraordinary cognitive capabilities based on these unique brain structures? We conclude that studying the brain of a remarkable person like Albert Einstein indeed provides us a better example to comprehensively appreciate the relationship between brain structures and advanced cognitive functions. However, caution must be exercised so as not to over-interpret his intelligence solely based on the understanding of the surface structures of his brain.

  10. BOOK REVIEW: Once Upon Einstein

    Science.gov (United States)

    Giannetto, E.

    2007-07-01

    Thibault Damour is a theoretical physicist, and a member of the French Academy of Sciences. This book is the translation, by Eric Novak, of the original French Si Einstein m'etait conté (Le Cherche Midi, 2005). It is neither a book of theoretical physics nor a biography of Einstein. It is not a book of history nor philosophy of science. In Damour's words it was written to encourage the reader to share with Einstein `those times when he understood some part of the hidden order of the universe'. It is a relatively short book, written in a very fluent style, but it deals with all the major problems and achievements of Einstein's works. Starting from special relativity, it continues with general relativity, quantum theories, unified field theory and a brief overview of the actual research related to Einstein's legacy. It is essentially a popular science book with some related exploration in history and philosophy to interpret physical theories. The most important problem discussed by Damour is the nature of time. On this subject, there is a very interesting short paragraph (pp 33--35) dedicated to the reception of the relativity idea by the great writer Marcel Proust and its counterpart within À la Recherche du Temps Perdu. A correct discussion of the implications of a relativistic time should imply the distinction of the different possible interpretations of this concept. Damour seems to conclude that only one interpretation is possible: `time does not exist', flowing of time is an illusion. One has to know that Einstein's ideas on time were related to Spinoza's perspective of a knowledge sub specie aeternitatis. However, other interpretations are possible and are related to the idea of time as an actuality. Damour speaks about the controversy between Einstein and Bergson, but Bergson is considered as a philosopher who did not understand relativity. This philosophical problem of relativistic time is indeed related to a historical problem briefly discussed by Damour

  11. Einstein 1905-1955: His Approach to Physics

    Science.gov (United States)

    Damour, Thibault

    We review Einstein's epistemological conceptions, and indicate their philosophical roots. The particular importance of the ideas of Hume, Kant, Mach, and Poincaré is highlighted. The specific characteristics of Einstein's approach to physics are underlined. Lastly, we consider the practical application of Einstein's methodological principles to the two theories of relativity, and to quantum theory. We emphasize a Kantian approach to quantum theory.

  12. Einstein's first paper on relativity

    International Nuclear Information System (INIS)

    Schwartz, H.M.

    1977-01-01

    Because of its exceptional significance in the history of great ideas in science, Einstein's first paper on relativity, especially its first part, deserves a more careful translation into English than presently exists. A new and annotated translation of this first part is presented here, together with a brief discussion of certain aspects of Einstein's paper

  13. CP Violation course

    CERN Multimedia

    CERN. Geneva HR-RFA

    2006-01-01

    The lecture introduces the concepts and phenomena of matter-antimatter symmetry violation, so-called "CP" violation. The lecture is organized in four courses, the first being devoted to a historical overview and an introduction into fundamental discrete symmetries. The second course introduces the most compelling CP-violating phenomena, and presents the first experimental discovery of CP violation in the neutral kaon system. The third course discusses how CP violation is beautifully incorporated into the Standard Model of particle interactions, and how modern B-meson "factories" provide precise tests of this picture. Finally, the fourth and last course introduces CP violation and the genesis of our matter world.

  14. Einstein and a century of time

    Science.gov (United States)

    Raine, D. J.

    2005-09-01

    In a world overabundant in information, a subject is defined by its iconography. Physics is the falling apple, the planetary atom, the laser, the mushroom cloud and the image of the later Einstein - images that represent, respectively, gravity, atomic theory, quantum theory, mass-energy and the scientist who had a hand in all four. It is therefore appropriate that World Year of Physics is called Einstein Year in the UK. Of course one can argue that progress in science depends on the contributions of many people; that there are other geniuses in physics, even some colourful personalities. Nevertheless there are fundamental reasons why Einstein's early achievements stand out even in their company. When at last the thought came to him that 'time itself was suspect', Einstein had found a new insight into the nature of the physical universe. It is this: that the universal properties of material objects tell us about the nature of space and time, and it is through these properties, not philosophical logic or common sense, that we discover the structure of spacetime. The later Einstein turned this successful formula on its head and sought to use the properties of spacetime to define those of material objects, thereby seeking to abolish matter entirely in favour of geometry. Before I introduce this special feature of European Journal of Physics I will say a few words about what is not here. Like all great geniuses Einstein can be seen as the climax of what went before him and the initiation of what was to follow. Looking back we can see the influence of Mach's positivism, according to which the role of science is to relate observations to other observations; hence only observations can tell us what is 'real'. But Einstein also grew up with the family electromechanical businesses, which testifies to the reality of the Maxwellian electromagnetic fields: thus only theory can tell us what is real! As is well known, Einstein himself refused to accept the full consequences of

  15. Correct Linearization of Einstein's Equations

    Directory of Open Access Journals (Sweden)

    Rabounski D.

    2006-06-01

    Full Text Available Regularly Einstein's equations can be reduced to a wave form (linearly dependent from the second derivatives of the space metric in the absence of gravitation, the space rotation and Christoffel's symbols. As shown here, the origin of the problem is that one uses the general covariant theory of measurement. Here the wave form of Einstein's equations is obtained in the terms of Zelmanov's chronometric invariants (physically observable projections on the observer's time line and spatial section. The obtained equations depend on solely the second derivatives even if gravitation, the space rotation and Christoffel's symbols. The correct linearization proves: the Einstein equations are completely compatible with weak waves of the metric.

  16. Construction of Einstein-Sasaki metrics in D≥7

    International Nuclear Information System (INIS)

    Lue, H.; Pope, C. N.; Vazquez-Poritz, J. F.

    2007-01-01

    We construct explicit Einstein-Kaehler metrics in all even dimensions D=2n+4≥6, in terms of a 2n-dimensional Einstein-Kaehler base metric. These are cohomogeneity 2 metrics which have the new feature of including a NUT-type parameter, or gravomagnetic charge, in addition to..' in addition to mass and rotation parameters. Using a canonical construction, these metrics all yield Einstein-Sasaki metrics in dimensions D=2n+5≥7. As is commonly the case in this type of construction, for suitable choices of the free parameters the Einstein-Sasaki metrics can extend smoothly onto complete and nonsingular manifolds, even though the underlying Einstein-Kaehler metric has conical singularities. We discuss some explicit examples in the case of seven-dimensional Einstein-Sasaki spaces. These new spaces can provide supersymmetric backgrounds in M theory, which play a role in the AdS 4 /CFT 3 correspondence

  17. From hadronic parity violation to electron parity-violating experiments

    International Nuclear Information System (INIS)

    Oers, Willem T.H. van

    2010-01-01

    The weak interaction is manifested in parity-violating observables. With the weak interaction extremely well known parity-violating measurements in hadronic systems can be used to deduce strong interaction effects in those systems. Parity-violating analyzing powers in electron-proton scattering have led to determining the strange quark contributions to the charge and magnetization distributions of the nucleon. Parity-violating electron-proton and electron-electron scattering can also be performed to test the predictions of the Standard Model in the 'running' of the electroweak mixing angle or sin 2 θ W .

  18. Books on Einstein--Collectors' Delight

    Science.gov (United States)

    Khoon, Koh Aik; Jalal, Azman; Abd-Shukor, R.; Yatim, Baharudin; Talib, Ibrahim Abu; Daud, Abdul Razak; Samat, Supian

    2009-01-01

    A survey of thirteen books on Einstein is presented. Its gives an idea on how much is written about the man and how frequent are the publications. The year 2005 saw the most publications. It is the centenary for the Miraculous Year. Interestingly some books can just sustain their readers' interest with just words. Einstein comes alive with the…

  19. Einstein pictures the x-ray sky

    International Nuclear Information System (INIS)

    Hartline, B.K.

    1979-01-01

    The second High Energy Astronomy Observatory (HEAO-2, Einstein) is revolutionizing x-ray astronomy just as its namesake revolutionized physics. Earlier x-ray observatories, including HEAO-1, were designed to scan the sky for x-ray emitters. With Einstein, the challenge has shifted from discovering x-ray sources to understanding the processes producing the x-rays. But having 500 times the sensitivity of previous detectors, Einstein makes more than its share of discoveries, too. For example, it sees distant quasars and clusters of galaxies that can barely be detected by the largest optical telescopes

  20. Behavioral Phenotype of Fragile X Syndrome in Adolescence and Adulthood

    Science.gov (United States)

    Smith, Leann E.; Barker, Erin T.; Seltzer, Marsha Mailick; Abbeduto, Leonard; Greenberg, Jan S.

    2012-01-01

    The present study explored the behavioral profile of individuals with fragile X syndrome during adolescence and adulthood. Individuals with both fragile X syndrome and autism (n = 30) were compared with (a) individuals diagnosed with fragile X syndrome (but not autism; n = 106) and (b) individuals diagnosed with autism (but not fragile X syndrome;…

  1. Autism Spectrum Disorder and Fragile X Syndrome

    Science.gov (United States)

    ... only after another family member has been diagnosed. Autism Spectrum Disorder and Fragile X Syndrome Fragile X syndrome is ... gene cause of ASD What Is Autism Spectrum Disorder? Autism spectrum disorder (ASD) is a behavioral diagnosis. The range ...

  2. Relay testing parametric investigation of seismic fragility

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.; Hofmayer, C.; Kassir, M.; Pepper, S.

    1989-01-01

    The seismic capacity of most electrical equipment is governed by malfunction of relays. An evaluation of the existing relay test data base at Brookhaven National Laboratory (BNL) has indicated that the seismic fragility of a relay may depend on various parameters related to the design or the input motion. In particular, the electrical mode, contact state, adjustment, chatter duration acceptance limit, and the frequency and the direction of the vibration input have been considered to influence the relay fragility level. For a particular relay type, the dynamics of its moving parts depends on the exact model number and vintage and hence, these parameters may also influence the fragility level. In order to investigate the effect of most of these parameters on the seismic fragility level, BNL has conducted a relay test program. The testing has been performed at Wyle Laboratories. Establishing the correlation between the single frequency fragility test input and the corresponding multifrequency response spectrum (TRS) is also an objective of this test program. This paper discusses the methodology used for testing and presents a brief summary of important test results. 1 ref., 10 figs

  3. A student's guide to Einstein's major papers

    CERN Document Server

    Kennedy, Robert E

    2012-01-01

    Our understanding of the physical universe underwent a revolution in the early twentieth century - evolving from the classical physics of Newton, Galileo, and Maxwell to the modern physics of relativity and quantum mechanics. The dominant figure in this revolutionary change was Albert Einstein. In a single year, 1905, Einstein produced breakthrough works in three areas of physics: on the size and the effects of atoms; on the quantization of the electromagnetic field; and on the special theory of relativity. In 1916 he produced a fourth breakthrough work, the general theory of relativity. A Student's Guide to Einstein's Major Papers focuses on Einstein's contributions, setting his major works into their historical context, and then takes the reader through the details of each paper, including the mathematics. This book helps the reader appreciate the simplicity and insightfulness of Einstein's ideas and how revolutionary his work was, and locate it in the evolution of scientific thought begun by the ancient...

  4. Secrets of the old one Einstein, 1905

    CERN Document Server

    Bernstein, Jeremy

    2006-01-01

    In March 1905, at approximately eight week intervals, the Editor of the noted German physics journal, Annalen der Physik, received three hand-written manuscripts from a relatively unknown patent examiner in Bern, Switzerland. This patent examiner was the twenty-six year old Albert Einstein and the three papers would set the agenda for twentieth century physics. A fourth short paper was received in September 1905 and contained Einstein's derivation of the formula E=mc^2. These papers changed our lives in the twentieth century and beyond. While to a professional physicist the mathematics in these papers are quite straight forward, the ideas behind them are not. In fact, none of Einstein's contemporaries fully understood what he had done. In SECRETS OF THE OLD ONE: Einstein, 1905, renowned science writer Jeremy Bernstein makes these ideas accessible to a general reader with a limited background in mathematics. After reading this book, you will understand why 1905 is often designated as Einstein's miracle year.

  5. Seismic fragility of nuclear power plant components (Phase II)

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.; Kassir, M.K.; Pepper, S.E.

    1990-02-01

    As part of the Component Fragility Program which was initiated in FY 1985, three additional equipment classes have been evaluated. This report contains the fragility results and discussions on these equipment classes which are switchgear, I and C panels and relays. Both low and medium voltage switchgear assemblies have been considered and a separate fragility estimate for each type is provided. Test data on cabinets from the nuclear instrumentation/neutron monitoring system, plant/process protection system, solid state protective system and engineered safeguards test system comprise the BNL data base for I and C panels (NSSS). Fragility levels have been determined for various failure modes of switchgear and I ampersand C panels, and the deterministic results are presented in terms of test response spectra. In addition, the test data have been evaluated for estimating the respective probabilistic fragility levels which are expressed in terms of a median value, an uncertainty coefficient, a randomness coefficient and an HCLPF value. Due to a wide variation of relay design and the fragility level, a generic fragility level cannot be established for relays. 7 refs., 13 figs., 12 tabs

  6. Effects of moderate pump and Stokes chirp on chirped-probe pulse femtosecond coherent anti-Stokes Raman scattering thermometry

    KAUST Repository

    Gu, Mingming

    2018-01-08

    The effects of moderate levels of chirp in the pump and Stokes pulses on chirped-probe-pulse femtosecond coherent anti-Stokes Raman scattering (CPP fs CARS) were investigated. The frequency chirp in the pump and Stokes pulses was introduced by placing SF11 glass disks with thicknesses of 10 mm or 20 mm in the optical path for these beams. The magnitude of the chirp in the probe beam was much greater and was induced by placing a 30-cm rod of SF10 glass in the beam path. The temperature measurements were performed in hydrogen/air non-premixed flames stabilized on a Hencken burner at equivalence ratios of 0.3, 0.5, 0.7, and 1.0. We performed measurements with no disks in pump and Stokes beam paths, and then with disks of 10 mm and 20 mm placed in both beam paths. The spectrum of the nonresonant background four-wave mixing signal narrowed considerably with increasing pump and Stokes chirp, while the resonant CARS signal was relatively unaffected. Consequently, the interference of the nonresonant background with the resonant CARS signal in the frequency-spread dephasing region of the spectrum was minimized. The increased rate of decay of the resonant CARS signal with increasing temperature was thus readily apparent. We have started to analyze the CPP fs CARS thermometry data and initial results indicate improved accuracy and precision are obtained due to moderate chirp in the pump and Stokes laser pulses.

  7. Realization of the purely spatial Einstein-Podolsky-Rosen paradox in full-field images of spontaneous parametric down-conversion

    Science.gov (United States)

    Moreau, Paul-Antoine; Mougin-Sisini, Joé; Devaux, Fabrice; Lantz, Eric

    2012-07-01

    We demonstrate Einstein-Podolsky-Rosen (EPR) entanglement by detecting purely spatial quantum correlations in the near and far fields of spontaneous parametric down-conversion generated in a type-2 beta barium borate crystal. Full-field imaging is performed in the photon-counting regime with an electron-multiplying CCD camera. The data are used without any postselection, and we obtain a violation of Heisenberg inequalities with inferred quantities taking into account all the biphoton pairs in both the near and far fields by integration on the entire two-dimensional transverse planes. This ensures a rigorous demonstration of the EPR paradox in its original position-momentum form.

  8. Einstein's Mirror

    Science.gov (United States)

    Gjurchinovski, Aleksandar; Skeparovski, Aleksandar

    2008-10-01

    Reflection of light from a plane mirror in uniform rectilinear motion is a century-old problem, intimately related to the foundations of special relativity.1-4 The problem was first investigated by Einstein in his famous 1905 paper by using the Lorentz transformations to switch from the mirror's rest frame to the frame where the mirror moves at a constant velocity.5 Einstein showed an intriguing fact that the usual law of reflection would not hold in the case of a uniformly moving mirror, that is, the angles of incidence and reflection of the light would not equal each other. Later on, it has been shown that the law of reflection at a moving mirror can be obtained in various alternative ways,6-10 but none of them seems suitable for bringing this interesting subject into the high school classroom.

  9. Stokes line width

    International Nuclear Information System (INIS)

    Nikiskov, A.I.; Ritus, V.I.

    1993-01-01

    The concept of Stokes line width is introduced for the asymptotic expansions of functions near an essential singularity. Explicit expressions are found for functions (switching functions) that switch on the exponentially small terms for the Dawson integral, Airy function, and the gamma function. A different, more natural representation of a function, not associated with expansion in an asymptotic series, in the form of dominant and recessive terms is obtained by a special division of the contour integral which represents the function into contributions of higher and lower saddle points. This division leads to a narrower, natural Stokes line width and a switching function of an argument that depends on the topology of the lines of steepest descent from the saddle point

  10. The Einstein-Podolsky-Rosen paradox

    International Nuclear Information System (INIS)

    Roy, S.M.

    1980-01-01

    The celebrated arguments of Einstein, Podolsky and Rosen claiming that quantum mechanics cannot be a complete theory are reviewed. Recent research climaxed by Bell's theorem shows that Einstein's locality or ''no telepathy'' postulate conflicts with quantum theory. It adds a new dimension to the paradox by catapulting the problem from the domain of metaphysics into that of experimental physics. (auth.)

  11. The times of Albert Einstein

    International Nuclear Information System (INIS)

    Ahmad, S.M.W.

    1990-09-01

    ''The life of Albert Einstein has a dramatic quality that does not rest exclusively on his theory of relativity. The extravagant timing of history linked him with three shattering developments of the twentieth century: the rise and fall of Nazi Germany, the birth of nuclear weapons, and the birth of zionism (and Israel). Their impact on Einstein's genius combined to drive him into a contact with the affairs of the world for which Einstein had little taste''. This article is the result of my lecture delivered at ICTP on 17 August, 1990 before a knowledgable audience that included scientists from many countries including the third world countries. This one and half hour lecture was organised by Dr. A.M. Hamende and Dr. H.R. Dalafi. 10 refs

  12. Resilience and the Fragile City

    Directory of Open Access Journals (Sweden)

    John de Boer

    2015-04-01

    Full Text Available Humanitarian, security, and development actors are witnessing two distinct but intertwined trends that will have a dramatic impact on their operations. The first relates to the fact that the locus of global poverty and vulnerability to disaster are increasingly concentrated in fragile and conflict affected states. The second trend is associated with the notion that the world has entered a period of unprecedented urbanization. For the first time in history, more people live inside urban centres than outside of them. As the world continues to urbanize, global emergencies will increasingly be concentrated in cities, particularly in lower income and fragile countries where the pace of urbanization is fastest. Yet, despite the growing risks facing urban populations living in fragile and conflict affected countries, there is very little understanding of what can be done to reduce the risks posed to these cities and their populations.

  13. Albert Einstein, Analogizer Extraordinaire

    CERN Multimedia

    CERN. Geneva

    2007-01-01

    Where does deep insight in physics come from? It is tempting to think that it comes from the purest and most precise of reasoning, following ironclad laws of thought that compel the clear mind completely rigidly. And yet the truth is quite otherwise. One finds, when one looks closely at any major discovery, that the greatest of physicists are, in some sense, the most crazily daring and irrational of all physicists. Albert Einstein exemplifies this thesis in spades. In this talk I will describe the key role, throughout Albert Einstein's fabulously creative life, played by wild guesses made by analogy lacking any basis whatsoever in pure reasoning. In particular, in this year of 2007, the centenary of 1907, I will describe how over the course of two years (1905 through 1907) of pondering, Einstein slowly came, via analogy, to understand the full, radical consequences of the equation that he had first discovered and published in 1905, arguably the most famous equation of all time: E = mc2.

  14. The Einstein-Vlasov System/Kinetic Theory.

    Science.gov (United States)

    Andréasson, Håkan

    2011-01-01

    The main purpose of this article is to provide a guide to theorems on global properties of solutions to the Einstein-Vlasov system. This system couples Einstein's equations to a kinetic matter model. Kinetic theory has been an important field of research during several decades in which the main focus has been on non-relativistic and special relativistic physics, i.e., to model the dynamics of neutral gases, plasmas, and Newtonian self-gravitating systems. In 1990, Rendall and Rein initiated a mathematical study of the Einstein-Vlasov system. Since then many theorems on global properties of solutions to this system have been established. This paper gives introductions to kinetic theory in non-curved spacetimes and then the Einstein-Vlasov system is introduced. We believe that a good understanding of kinetic theory in non-curved spacetimes is fundamental to a good comprehension of kinetic theory in general relativity.

  15. Covariant Conformal Decomposition of Einstein Equations

    Science.gov (United States)

    Gourgoulhon, E.; Novak, J.

    It has been shown1,2 that the usual 3+1 form of Einstein's equations may be ill-posed. This result has been previously observed in numerical simulations3,4. We present a 3+1 type formalism inspired by these works to decompose Einstein's equations. This decomposition is motivated by the aim of stable numerical implementation and resolution of the equations. We introduce the conformal 3-``metric'' (scaled by the determinant of the usual 3-metric) which is a tensor density of weight -2/3. The Einstein equations are then derived in terms of this ``metric'', of the conformal extrinsic curvature and in terms of the associated derivative. We also introduce a flat 3-metric (the asymptotic metric for isolated systems) and the associated derivative. Finally, the generalized Dirac gauge (introduced by Smarr and York5) is used in this formalism and some examples of formulation of Einstein's equations are shown.

  16. Seismic fragility levels of nuclear power plant equipment

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1987-01-01

    Seismic fragility levels of safety-related electrical and mechanical equipment used in nuclear power plants are discussed. The fragility level is defined as the vibration level corresponding to initiation of equipment malfunctions. The test response spectrum is used as a measure of this vibration level. The fragility phenomenon of an equipment is represented by a number of response spectra corresponding to various failure modes. Analysis methods are described for determination of the fragility level by use of existing test data. Useful conversion factors are tabulated to transform test response spectra from one damping value to another. Results are presented for switch-gears and motor control centers. The capacity levels of these equipment assemblies are observed to be limited by malfunctioning of contactors, motor starters, relays and/or switches. The applicability of the fragility levels, determined in terms of test response spectra, to Seismic Margin Studies and Probabilistic Risk Assessments is discussed and specific recommendations are provided

  17. Einstein in love a scientific romance

    CERN Document Server

    Overbye, Dennis

    2000-01-01

    At its height, Einstein's marriage to Mileva was an extraordinary one - a colleague and often fierce adversary, Mileva was brilliantly matched with the scientific genius. Dennis Overbye seeks to present this scientific romance in a vivid light, telling the private story of the young Einstein.

  18. Einstein, Kant, and Taoism

    OpenAIRE

    Kim, Y. S.

    2006-01-01

    It is said that Einstein's conceptual base for the theory of relativity was the philosophy formulated by Immanuel Kant. Then, is it possible to see how Kant played a role in Einstein's thinking without reading Kant's books? This question arises because it is not possible for physicists to read Kant's writings. Yes, it is possible if we use the method of physics. It is known also that Kant's mode of thinking was profoundly affected by the geography of Koenigsberg where he spent eighty years of...

  19. Ceremony marking Einstein Year

    CERN Multimedia

    2005-01-01

    Sunday 13th November at 10:00amat Geneva's St. Peter's Cathedral To mark Einstein Year and the importance of the intercultural dialogue of which it forms a part, a religious service will take place on Sunday 13 November at 10 a.m. in St. Peter's Cathedral, to which CERN members and colleagues are warmly welcomed. Pastor Henry Babel, senior minister at the Cathedral, will speak on the theme: 'God in Einstein's Universe'. Diether Blechschmidt will convey a message on behalf of the scientific community.

  20. Quantum theory and Einstein's general relativity

    International Nuclear Information System (INIS)

    Borzeszkowski, H. von; Treder, H.

    1982-01-01

    We dicusss the meaning and prove the accordance of general relativity, wave mechanics, and the quantization of Einstein's gravitation equations themselves. Firstly, we have the problem of the influence of gravitational fields on the de Broglie waves, which influence is in accordance with Einstein's weak principle of equivalence and the limitation of measurements given by Heisenberg's uncertainty relations. Secondly, the quantization of the gravitational fields is a ''quantization of geometry.'' However, classical and quantum gravitation have the same physical meaning according to limitations of measurements given by Einstein's strong principle of equivalence and the Heisenberg uncertainties for the mechanics of test bodies

  1. Study on the Progress of Ecological Fragility Assessment in China

    Science.gov (United States)

    Chen, Pei; Hou, Kang; Chang, Yue; Li, Xuxiang; Zhang, Yunwei

    2018-02-01

    The basic elements of human survival are based on the ecological environment. The development of social economic and the security of the ecological environment are closely linked and interact with each other. The fragility of the environment directly affects the stability of the regional ecosystem and the sustainable development of the ecological environment. As part of the division of the national ecological security, the assessment of ecological fragility has become a hot and difficult issue in environmental research, and researchers at home and abroad have systematically studied the causes and states of ecological fragility. The assessment of regional ecological fragility is a qualitative and quantitative analysis of the unbalanced distribution of ecological environment factors caused by human socio-economic activities or changes in ecosystems. At present, researches on ecological fragility has not formed a complete and unified index assessment system, and the unity of the assessment model has a direct impact on the accuracy of the index weights. Therefore, the discussion on selection of ecological fragility indexes and the improvement of ecological fragility assessment model is necessary, which is good for the improvement of ecological fragility assessment system in China.

  2. Frequency of fragile-x in x‑linked mental retardation

    African Journals Online (AJOL)

    ... with isolated mental retardation or autism of unknown etiology with considerable fragile X dysmorphic features or established family history of fragile X syndrome, chromosomal study that identifies the fragile site at Xq27.3 in addition to other cytogenetic abnormalities could be useful or early diagnosis and intervention by ...

  3. Spontaneous Lorentz and diffeomorphism violation, massive modes, and gravity

    International Nuclear Information System (INIS)

    Bluhm, Robert; Fung Shuhong; Kostelecky, V. Alan

    2008-01-01

    Theories with spontaneous local Lorentz and diffeomorphism violation contain massless Nambu-Goldstone modes, which arise as field excitations in the minimum of the symmetry-breaking potential. If the shape of the potential also allows excitations above the minimum, then an alternative gravitational Higgs mechanism can occur in which massive modes involving the metric appear. The origin and basic properties of the massive modes are addressed in the general context involving an arbitrary tensor vacuum value. Special attention is given to the case of bumblebee models, which are gravitationally coupled vector theories with spontaneous local Lorentz and diffeomorphism violation. Mode expansions are presented in both local and spacetime frames, revealing the Nambu-Goldstone and massive modes via decomposition of the metric and bumblebee fields, and the associated symmetry properties and gauge fixing are discussed. The class of bumblebee models with kinetic terms of the Maxwell form is used as a focus for more detailed study. The nature of the associated conservation laws and the interpretation as a candidate alternative to Einstein-Maxwell theory are investigated. Explicit examples involving smooth and Lagrange-multiplier potentials are studied to illustrate features of the massive modes, including their origin, nature, dispersion laws, and effects on gravitational interactions. In the weak static limit, the massive mode and Lagrange-multiplier fields are found to modify the Newton and Coulomb potentials. The nature and implications of these modifications are examined.

  4. Towards an Einstein-Podolsky-Rosen paradox between two macroscopic atomic ensembles at room temperature

    Science.gov (United States)

    He, Q. Y.; Reid, M. D.

    2013-06-01

    Experiments have reported the entanglement of two spatially separated macroscopic atomic ensembles at room temperature (Krauter et al 2011 Phys. Rev. Lett. 107 080503; Julsgaard et al 2001 Nature 413 400). We show how an Einstein-Podolsky-Rosen (EPR) paradox is realizable with this experiment. Our proposed test involves violation of an inferred Heisenberg uncertainty principle, which is a sufficient condition for an EPR paradox. This is a stronger test of nonlocality than entanglement. Our proposal would enable the first definitive confirmation of quantum EPR paradox correlations between two macroscopic objects at room temperature. This is a necessary intermediate step towards a nonlocal experiment with causal measurement separations. As well as having fundamental significance, the realization of an atomic EPR paradox could provide a resource for novel applications in quantum technology.

  5. Correspondence passed between Einstein and Schroedinger

    International Nuclear Information System (INIS)

    Balibar, F.

    1992-01-01

    The main points of the 26 year long correspondence between Einstein and Schroedinger are reviewed: from the de Broglie thesis and the Bose-Einstein statistics to the Schroedinger equation (1925-1926); from the EPR paradox to the cat parable (1935); a complete collaboration on unitary theories

  6. Rivaroxaban for the treatment of symptomatic deep-vein thrombosis and pulmonary embolism in Chinese patients: a subgroup analysis of the EINSTEIN DVT and PE studies.

    Science.gov (United States)

    Wang, Yuqi; Wang, Chen; Chen, Zhong; Zhang, Jiwei; Liu, Zhihong; Jin, Bi; Ying, Kejing; Liu, Changwei; Shao, Yuxia; Jing, Zhicheng; Meng, Isabelle Ling; Prins, Martin H; Pap, Akos F; Müller, Katharina; Lensing, Anthonie Wa

    2013-12-16

    The worldwide EINSTEIN DVT and EINSTEIN PE studies randomized 8282 patients with acute symptomatic deep-vein thrombosis (DVT) and/or pulmonary embolism (PE) and, for the first time in trials in this setting, included patients in China. This analysis evaluates the results of these studies in this subgroup of patients. A total of 439 Chinese patients who had acute symptomatic DVT (n=211), or PE with or without DVT (n=228), were randomized to receive rivaroxaban (15 mg twice daily for 21 days, followed by 20 mg once daily) or standard therapy of enoxaparin overlapping with and followed by an adjusted-dose vitamin K antagonist, for 3, 6, or 12 months. The primary efficacy outcome was symptomatic recurrent venous thromboembolism. The principal safety outcome was major or non-major clinically relevant bleeding. The primary efficacy outcome occurred in seven (3.2%) of the 220 patients in the rivaroxaban group and in seven (3.2%) of the 219 patients in the standard-therapy group (hazard ratio, 1.04; 95% confidence interval 0.36-3.0; p=0.94). The principal safety outcome occurred in 13 (5.9%) patients in the rivaroxaban group and in 20 (9.2%) patients in the standard-therapy group (hazard ratio, 0.63; 95% confidence interval 0.31-1.26; p=0.19). Major bleeding was observed in no patients in the rivaroxaban group and in five (2.3%) patients in the standard-therapy group. In fragile patients (defined as age >75 years, creatinine clearance EINSTEIN PE, ClinicalTrials.gov NCT00439777; EINSTEIN DVT, ClinicalTrials.gov NCT00440193.

  7. Exact solutions of Einstein and Einstein-scalar equations in 2+1 dimensions

    International Nuclear Information System (INIS)

    Virbhadra, K.S.

    1995-01-01

    A nonstatic and circularly symmetric exact solution of the Einstein equations (with a cosmological constant Λ and null fluid) in 2 + 1 dimensions is given. This is a nonstatic generalization of the uncharged spinless Bandos Teitelboim Zanelli (BTZ) metric. For Λ = 0, spacetime is though not flat, the Kretschmann invariant vanishes. The energy, momentum, and power output for this metric are obtained. Further a static and circularly symmetric exact solution of the Einstein-massless scalar equations is given, which has a curvature singularity at r=0 and the scalar field diverges at r=0 as well as at infinity. (author). 12 refs

  8. Static Einstein--Maxwell field equations

    International Nuclear Information System (INIS)

    Das, A.

    1979-01-01

    The static Einstein--Maxwell field equations are investigated in the presence of both electric and magnetic fields. The sources or bodies are assumed to be of finite size and to not affect the connectivity of the associated space. Furthermore, electromagnetic and metric fields are assumed to have reasonable differentiabilities. It is then proved that the electric and magnetic field vectors are constant multiples of one another. Moreover, the static Einstein--Maxwell equations reduce to the static magnetovac case. If, furthermore, the variational derivation of the Einstein--Maxwell equations is assumed, then both the total electric and magnetic charge of each body must vanish. As a physical consequence it is pointed out that if a suspended magnet be electrically charged then it must experience a purely general relativistic torque

  9. Bose-Einstein condensation in microgravity.

    Science.gov (United States)

    van Zoest, T; Gaaloul, N; Singh, Y; Ahlers, H; Herr, W; Seidel, S T; Ertmer, W; Rasel, E; Eckart, M; Kajari, E; Arnold, S; Nandi, G; Schleich, W P; Walser, R; Vogel, A; Sengstock, K; Bongs, K; Lewoczko-Adamczyk, W; Schiemangk, M; Schuldt, T; Peters, A; Könemann, T; Müntinga, H; Lämmerzahl, C; Dittus, H; Steinmetz, T; Hänsch, T W; Reichel, J

    2010-06-18

    Albert Einstein's insight that it is impossible to distinguish a local experiment in a "freely falling elevator" from one in free space led to the development of the theory of general relativity. The wave nature of matter manifests itself in a striking way in Bose-Einstein condensates, where millions of atoms lose their identity and can be described by a single macroscopic wave function. We combine these two topics and report the preparation and observation of a Bose-Einstein condensate during free fall in a 146-meter-tall evacuated drop tower. During the expansion over 1 second, the atoms form a giant coherent matter wave that is delocalized on a millimeter scale, which represents a promising source for matter-wave interferometry to test the universality of free fall with quantum matter.

  10. Statistics in a Trilinear Interacting Stokes-Antistokes Boson System

    Science.gov (United States)

    Tänzler, W.; Schütte, F.-J.

    The statistics of a system of four boson modes is treated with simultaneous Stokes-Antistokes interaction taking place. The time evolution is calculated in full quantum manner but in short time approximation. Mean photon numbers and correlations of second order are calculated. Antibunching can be found in the laser mode and in the system of Stokes and Antistokes mode.Translated AbstractStatistik in einem trilinear wechselwirkenden Stokes-Antistokes-BosonensystemDie Statistik eines Systems von vier Bosonenmoden mit gleichzeitiger Stokes-Antistokes-Wechselwirkung wird bei vollquantenphysikalischer Beschreibung in Kurzzeitnäherung untersucht. Mittlere Photonenzahlen und Korrelationen zweiter Ordnung werden berechnet. Dabei wird Antibunching sowohl in der Lasermode allein als auch im System aus Stokes- und Antistokesmode gefunden.

  11. Component fragilities. Data collection, analysis and interpretation

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1985-01-01

    As part of the component fragility research program sponsored by the US NRC, BNL is involved in establishing seismic fragility levels for various nuclear power plant equipment with emphasis on electrical equipment. To date, BNL has reviewed approximately seventy test reports to collect fragility or high level test data for switchgears, motor control centers and similar electrical cabinets, valve actuators and numerous electrical and control devices, e.g., switches, transmitters, potentiometers, indicators, relays, etc., of various manufacturers and models. BNL has also obtained test data from EPRI/ANCO. Analysis of the collected data reveals that fragility levels can best be described by a group of curves corresponding to various failure modes. The lower bound curve indicates the initiation of malfunctioning or structural damage, whereas the upper bound curve corresponds to overall failure of the equipment based on known failure modes occurring separately or interactively. For some components, the upper and lower bound fragility levels are observed to vary appreciably depending upon the manufacturers and models. For some devices, testing even at the shake table vibration limit does not exhibit any failure. Failure of a relay is observed to be a frequent cause of failure of an electrical panel or a system. An extensive amount of additional fregility or high level test data exists

  12. Unsteady Stokes equations: Some complete general solutions

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    homogeneous unsteady Stokes equations are examined. A necessary and sufficient condition for a divergence-free vector to represent the velocity field of a possible unsteady Stokes flow in the absence of body forces is derived. Keywords. Complete ...

  13. Einstein's essays in science

    CERN Document Server

    Einstein, Albert

    2009-01-01

    His name is synonymous with ""genius,"" but these essays by the renowned physicist and scholar are accessible to any reader. In addition to outlining the core of relativity theory in everyday language, Albert Einstein presents fascinating discussions of other scientific fields to which he made significant contributions. The Nobel Laureate also profiles some of history's most influential physicists, upon whose studies his own work was based.Assembled during Einstein's lifetime from his speeches and essays, this book marks the first presentation to the wider world of the scientist's accomplishme

  14. Ethic and Evolution in Boltzmann's and Einstein's Thought

    Energy Technology Data Exchange (ETDEWEB)

    Broda, E.

    1980-07-01

    In physics and to a large extent in epistomology, Einstein was the natural successor to Boltzmann. But while Boltzmann was an ardent evolutionist, Einstein cared little for biology. Boltzmann applied Darwinian principles also to ethics, but remained aloof from politics. In contrast, Einstein's morality, though expressed in magnificent and selfless activity, lacked a firm theoretical basis. (author)

  15. Ethic and Evolution in Boltzmann's and Einstein's Thought

    International Nuclear Information System (INIS)

    Broda, E.

    1980-01-01

    In physics and to a large extent in epistomology, Einstein was the natural successor to Boltzmann. But while Boltzmann was an ardent evolutionist, Einstein cared little for biology. Boltzmann applied Darwinian principles also to ethics, but remained aloof from politics. In contrast, Einstein's morality, though expressed in magnificent and selfless activity, lacked a firm theoretical basis. (author)

  16. BANKING SYSTEM FRAGILITY: CASE OF THE REPUBLIC OF MOLDOVA

    Directory of Open Access Journals (Sweden)

    Dorina CLICHICI

    2014-04-01

    Full Text Available The paper studied the determinants of Moldovan banking system fragility. It underlines the existing researches into the empirical determinants of banking fragility. The analysis revealed that there are numerous channels through which weaknesses within the macroeconomic conditions and structural characteristics might increase banking system fragility. The main macroeconomic determinants which may have an impact on Moldovan banking system fragility are: excessive domestic liquidity, pro-cyclical character of the banking system, dependence on remittances, financial dollarization. There are also several banking characteristics which play a role for Moldovan banking system fragility: the undermined intermediation function, high level of bad loans, uncertainties in the ownership structure, low presence of foreign strategic investors. The paper employed a quantitative, a qualitative and a comparative analysis using the financial soundness and structural indicators of the Moldovan banking system in order to assess the impact of various determinants on Moldovan banking system fragility. The results reveal a high degree of capitalization and liquidity of Moldovan banking system, factors which contribute and maintain the general stability of the entire financial system.

  17. Longitudinal Profiles of Adaptive Behavior in Fragile X Syndrome

    Science.gov (United States)

    Quintin, Eve-Marie; Jo, Booil; Lightbody, Amy A.; Hazlett, Heather Cody; Piven, Joseph; Hall, Scott S.; Reiss, Allan L.

    2014-01-01

    OBJECTIVE: To examine longitudinally the adaptive behavior patterns in fragile X syndrome. METHOD: Caregivers of 275 children and adolescents with fragile X syndrome and 225 typically developing children and adolescents (2–18 years) were interviewed with the Vineland Adaptive Behavior Scales every 2 to 4 years as part of a prospective longitudinal study. RESULTS: Standard scores of adaptive behavior in people with fragile X syndrome are marked by a significant decline over time in all domains for males and in communication for females. Socialization skills are a relative strength as compared with the other domains for males with fragile X syndrome. Females with fragile X syndrome did not show a discernible pattern of developmental strengths and weaknesses. CONCLUSIONS: This is the first large-scale longitudinal study to show that the acquisition of adaptive behavior slows as individuals with fragile X syndrome age. It is imperative to ensure that assessments of adaptive behavior skills are part of intervention programs focusing on childhood and adolescence in this condition. PMID:25070318

  18. Fragile Butterfly

    DEFF Research Database (Denmark)

    2011-01-01

    Valg af materiale/medie/form: Med indlevelse og en unik balance af sårbarhed i stemmen synger og fortolker Heidie sine egne sange, hvis lyriske tekster grundlæggende har to temaer: En dyb kærlighed til livet og det at turde kærligheden. Toneuniverset i Fragile Butterfly tager sit afsæt i jazzen...

  19. Tracking development assistance for health to fragile states: 2005-2011.

    Science.gov (United States)

    Graves, Casey M; Haakenstad, Annie; Dieleman, Joseph L

    2015-03-19

    Development assistance for health (DAH) has grown substantially, totaling more than $31.3 billion in 2013. However, the degree that countries with high concentrations of armed conflict, ethnic violence, inequality, debt, and corruption have received this health aid and how that assistance might be different from the funding provided to other countries has not been assessed. We combine DAH estimates and a multidimensional fragile states index for 2005 through 2011. We disaggregate and compare total DAH disbursed for fragile states versus stable states. Between 2005 and 2011, DAH per person in fragile countries increased at an annualized rate of 5.4%. In 2011 DAH to fragile countries totaled $6.2 billion, which is $5.05 per person. This is 43% of total DAH that is traced to a country. Comparing low-income countries, funding channeled to fragile countries was $7.22 per person while stable countries received $11.15 per person. Relative to stable countries, donors preferred to provide more funding to low-income fragile countries that have refugees or ongoing external intervention but tended to avoid providing funding to countries with political gridlock, flawed elections, or economic decline. In 2011, Ethiopia received the most health aid of all fragile countries, while the United States provided the most funds to fragile countries. In 2011, 1.2 billion people lived in fragile countries. DAH can bolster health systems and might be especially valuable in providing long-term stability in fragile environments. While external health funding to these countries has increased since 2005, it is, in per person terms, almost half as much as the DAH provided to stable countries of comparable income levels.

  20. Einstein and solid-state physics

    International Nuclear Information System (INIS)

    Aut, I.

    1982-01-01

    A connection between the development of solid-state physics and the works and activity of Albert Einstein is traced. A tremendous Einstein contribution to solid state physics is marked. A strict establishment of particle-wave dualism; a conclusion about the applicability of the Plank radiation law not only to black body radiation; finding out particles indistinguishability - all three discoveries have a principle significance for solid state physics too

  1. Einstein and the twin paradox

    International Nuclear Information System (INIS)

    Pesic, Peter

    2003-01-01

    Einstein was the first to discuss and resolve the 'twin paradox', which in 1905 he did not consider paradoxical and treated as a consequence of lack of simultaneity. He maintained this view until at least 1914. However, in 1918 Einstein brought forward arguments about accelerated frames of reference that tended to overshadow his initial resolution. His earlier arguments were gradually rediscovered during the subsequent controversy about this 'paradox'

  2. A note on families of fragility curves

    International Nuclear Information System (INIS)

    Kaplan, S.; Bier, V.M.; Bley, D.C.

    1989-01-01

    In the quantitative assessment of seismic risk, uncertainty in the fragility of a structural component is usually expressed by putting forth a family of fragility curves, with probability serving as the parameter of the family. Commonly, a lognormal shape is used both for the individual curves and for the expression of uncertainty over the family. A so-called composite single curve can also be drawn and used for purposes of approximation. This composite curve is often regarded as equivalent to the mean curve of the family. The equality seems intuitively reasonable, but according to the authors has never been proven. The paper presented proves this equivalence hypothesis mathematically. Moreover, the authors show that this equivalence hypothesis between fragility curves is itself equivalent to an identity property of the standard normal probability curve. Thus, in the course of proving the fragility curve hypothesis, the authors have also proved a rather obscure, but interesting and perhaps previously unrecognized, property of the standard normal curve

  3. Entanglement Equilibrium and the Einstein Equation.

    Science.gov (United States)

    Jacobson, Ted

    2016-05-20

    A link between the semiclassical Einstein equation and a maximal vacuum entanglement hypothesis is established. The hypothesis asserts that entanglement entropy in small geodesic balls is maximized at fixed volume in a locally maximally symmetric vacuum state of geometry and quantum fields. A qualitative argument suggests that the Einstein equation implies the validity of the hypothesis. A more precise argument shows that, for first-order variations of the local vacuum state of conformal quantum fields, the vacuum entanglement is stationary if and only if the Einstein equation holds. For nonconformal fields, the same conclusion follows modulo a conjecture about the variation of entanglement entropy.

  4. An Einstein-Cartan Fine Structure Constant Definition

    Directory of Open Access Journals (Sweden)

    Stone R. A. Jr.

    2010-01-01

    Full Text Available The fine structure constant definition given in Stone R.A. Jr. Progress in Physics, 2010, v.1, 11-13 is compared to an Einstein-Cartan fine structure constant definition. It is shown that the Einstein-Cartan definition produces the correct pure theory value, just not the measure value. To produce the measured value, the pure theory Einstein-Cartan fine structure constant requires only the new variables and spin coupling of the fine structure constant definition in [1].

  5. Albert Einstein and the relativity theory

    International Nuclear Information System (INIS)

    Pavlickova, E.

    1975-01-01

    A bibliography is presented of Albert Einstein's works, listing his correspondence, biographical literature, articles on A. Einstein published in Czech journals, principal relativity theory monographs and popular, historical and philosophical publications. The bibliographical records are listed alphabetically. Most references give the abbreviations of libraries where the publications are available. (J.P.)

  6. BOOK REVIEW: A Student's Guide to Einstein's Major Papers A Student's Guide to Einstein's Major Papers

    Science.gov (United States)

    Janssen, Michel

    2013-12-01

    The core of this volume is formed by four chapters (2-5) with detailed reconstructions of the arguments and derivations in four of Einstein's most important papers, the three main papers of his annus mirabilis 1905 (on the light quantum, Brownian motion, and special relativity) and his first systematic exposition of general relativity of 1916. The derivations are given in sufficient detail and in sufficiently modernized notation (without any serious distortion of the originals) for an undergraduate physics major to read and understand them with far less effort than it would take him or her to understand (English translations of) Einstein's original papers. Each of these four papers is accompanied by a detailed introduction, which covers the conceptual development of the relevant field prior to Einstein's contribution to it and corrects some of the myths surrounding these papers that still have not been fully eradicated among physicists. (One quibble: though Kennedy correctly points out that the goal of the light quantum paper was not to explain the photoelectric effect, it is also not quite right to say that 'it was written to explain the Wien region of blackbody radiation' (p. xv). Einstein used this explanatory feat as the central argument for his light quantum hypothesis.) These four chapters then are the most valuable part of the volume. They could be used, independently of one another, but preferably in conjunction with Einstein's original texts, in courses on quantum mechanics, statistical mechanics, electrodynamics, and general relativity, respectively, to add a historical component to such courses. As a historian of science embedded in a physics department who is regularly called upon to give guest lectures in such courses on the history of their subjects, I can highly recommend the volume for this purpose. However, I would not adopt this volume as (one of) the central text(s) for a course on the history of modern physics. For one thing, chapter 1, which in

  7. Linear Einstein equations and Kerr-Schild maps

    International Nuclear Information System (INIS)

    Gergely, Laszlo A

    2002-01-01

    We prove that given a solution of the Einstein equations g ab for the matter field T ab , an autoparallel null vector field l a and a solution (l a l c , T ac ) of the linearized Einstein equation on the given background, the Kerr-Schild metric g ac + λl a l c (λ arbitrary constant) is an exact solution of the Einstein equation for the energy-momentum tensor T ac + λT ac + λ 2 l (a T c)b l b . The mixed form of the Einstein equation for Kerr-Schild metrics with autoparallel null congruence is also linear. Some more technical conditions hold when the null congruence is not autoparallel. These results generalize previous theorems for vacuum due to Xanthopoulos and for flat seed spacetime due to Guerses and Guersey

  8. 21 CFR 864.6600 - Osmotic fragility test.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Osmotic fragility test. 864.6600 Section 864.6600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6600 Osmotic fragility...

  9. On static black holes solutions in Einstein and Einstein-Gauss-Bonnet gravity with topology [Formula: see text].

    Science.gov (United States)

    Dadhich, Naresh; Pons, Josep M

    We study static black hole solutions in Einstein and Einstein-Gauss-Bonnet gravity with the topology of the product of two spheres, [Formula: see text], in higher dimensions. There is an unusual new feature of the Gauss-Bonnet black hole: the avoidance of a non-central naked singularity prescribes a mass range for the black hole in terms of [Formula: see text]. For an Einstein-Gauss-Bonnet black hole a limited window of negative values for [Formula: see text] is also permitted. This topology encompasses black strings, branes, and generalized Nariai metrics. We also give new solutions with the product of two spheres of constant curvature.

  10. CERN physicist receives Einstein Medal

    CERN Multimedia

    2006-01-01

    On 29 June the CERN theorist Gabriele Veneziano was awarded the prestigious Albert Einstein Medal for significant contributions to the understanding of string theory. This award is given by the Albert Einstein Society in Bern to individuals whose scientific contributions relate to the work of Einstein. Former recipients include exceptional physicists such as Murray Gell-Mann last year, but also Stephen Hawking and Victor Weisskopf. Gabriele Veneziano, a member of the integrated CERN Theory Team since 1977, led the Theory Division from 1994 to 1997 and has already received many prestigious prizes for his outstanding work, including the Enrico Fermi Prize (see CERN Courier, November 2005), the Dannie Heineman Prize for mathematical physics of the American Physical Society in 2004 (see Bulletin No. 47/2003), and the I. Ya. Pomeranchuk Prize of the Institute of Theoretical and Experimental Physics (Moscow) in 1999.

  11. Einstein as a Missionary of Science

    Science.gov (United States)

    Renn, Jürgen

    2013-01-01

    The paper reviews Einstein's engagement as a mediator and popularizer of science. It discusses the formative role of popular scientific literature for the young Einstein, showing that not only his broad scientific outlook but also his internationalist political views were shaped by these readings. Then, on the basis of recent detailed…

  12. Navier-Stokes equations an introduction with applications

    CERN Document Server

    Łukaszewicz, Grzegorz

    2016-01-01

    This volume is devoted to the study of the Navier–Stokes equations, providing a comprehensive reference for a range of applications: from students to engineers and mathematicians involved in research on fluid mechanics, dynamical systems, and mathematical modeling. Equipped with only a basic knowledge of calculus, functional analysis, and partial differential equations, the reader is introduced to the concept and applications of the Navier–Stokes equations through a series of fully self-contained chapters. Including lively illustrations that complement and elucidate the text, and a collection of exercises at the end of each chapter, this book is an indispensable, accessible, classroom-tested tool for teaching and understanding the Navier–Stokes equations. Incompressible Navier–Stokes equations describe the dynamic motion (flow) of incompressible fluid, the unknowns being the velocity and pressure as functions of location (space) and time variables. A solution to these equations predicts the behavior o...

  13. On entanglement of light and Stokes parameters

    International Nuclear Information System (INIS)

    Żukowski, Marek; Laskowski, Wiesław; Wieśniak, Marcin

    2016-01-01

    We present a new approach to Stokes parameters, which enables one to see better non-classical properties of bright quantum light, and of undefined overall photon numbers. The crucial difference is as follows. The standard quantum optical Stokes parameters are averages of differences of intensities of light registered at the two exits of polarization analyzers, and one gets their normalized version by dividing them by the average total intensity. The new ones are averages of the registered normalized Stokes parameters, for the duration of the experiment. That is, we redefine each Stokes observable as the difference of photon number operators at the two exits of a polarizing beam splitter multiplied by the inverse of their sum. The vacuum eigenvalue of the operator is defined a zero. We show that with such an approach one can obtain more sensitive entanglement indicators based on polarization measurements. (paper)

  14. On entanglement of light and Stokes parameters

    Science.gov (United States)

    Żukowski, Marek; Laskowski, Wiesław; Wieśniak, Marcin

    2016-08-01

    We present a new approach to Stokes parameters, which enables one to see better non-classical properties of bright quantum light, and of undefined overall photon numbers. The crucial difference is as follows. The standard quantum optical Stokes parameters are averages of differences of intensities of light registered at the two exits of polarization analyzers, and one gets their normalized version by dividing them by the average total intensity. The new ones are averages of the registered normalized Stokes parameters, for the duration of the experiment. That is, we redefine each Stokes observable as the difference of photon number operators at the two exits of a polarizing beam splitter multiplied by the inverse of their sum. The vacuum eigenvalue of the operator is defined a zero. We show that with such an approach one can obtain more sensitive entanglement indicators based on polarization measurements.

  15. T-violating effects in neutron physics and CP-violation in gauge models

    International Nuclear Information System (INIS)

    Herczeg, P.

    1987-01-01

    Discussed in this paper is the subject of T-violation in the transmission of polarized neutrons through polarized and oriented targets. Considered is the possible size of the T-violating effects both from a phenomenological point of view, and also in gauge models with CP-violation. A brief discussion of T-violating effects in β-decay is included

  16. Einstein-Friedmann equation, nonlinear dynamics and chaotic behaviours

    International Nuclear Information System (INIS)

    Tanaka, Yosuke; Nakano, Shingo; Ohta, Shigetoshi; Mori, Keisuke; Horiuchi, Tanji

    2009-01-01

    We have studied the Einstein-Friedmann equation [Case 1] on the basis of the bifurcation theory and shown that the chaotic behaviours in the Einstein-Friedmann equation [Case 1] are reduced to the pitchfork bifurcation and the homoclinic bifurcation. We have obtained the following results: (i) 'The chaos region diagram' (the p-λ plane) in the Einstein-Friedmann equation [Case 1]. (ii) 'The chaos inducing chart' of the homoclinic orbital systems in the unforced differential equations. We have discussed the non-integrable conditions in the Einstein-Friedmann equation and proposed the chaotic model: p=p 0 ρ n (n≥0). In case n≠0,1, the Einstein-Friedmann equation is not integrable and there may occur chaotic behaviours. The cosmological constant (λ) turns out to play important roles for the non-integrable condition in the Einstein-Friedmann equation and also for the pitchfork bifurcation and the homoclinic bifurcation in the relativistic field equation. With the use of the E-infinity theory, we have also discussed the physical quantities in the gravitational field equations, and obtained the formula logκ=-10(1/φ) 2 [1+(φ) 8 ]=-26.737, which is in nice agreement with the experiment (-26.730).

  17. Linearized pseudo-Einstein equations on the Heisenberg group

    Science.gov (United States)

    Barletta, Elisabetta; Dragomir, Sorin; Jacobowitz, Howard

    2017-02-01

    We study the pseudo-Einstein equation R11bar = 0 on the Heisenberg group H1 = C × R. We consider first order perturbations θɛ =θ0 + ɛ θ and linearize the pseudo-Einstein equation about θ0 (the canonical Tanaka-Webster flat contact form on H1 thought of as a strictly pseudoconvex CR manifold). If θ =e2uθ0 the linearized pseudo-Einstein equation is Δb u - 4 | Lu|2 = 0 where Δb is the sublaplacian of (H1 ,θ0) and L bar is the Lewy operator. We solve the linearized pseudo-Einstein equation on a bounded domain Ω ⊂H1 by applying subelliptic theory i.e. existence and regularity results for weak subelliptic harmonic maps. We determine a solution u to the linearized pseudo-Einstein equation, possessing Heisenberg spherical symmetry, and such that u(x) → - ∞ as | x | → + ∞.

  18. Einstein y la complejidad

    Directory of Open Access Journals (Sweden)

    Jou, David

    2007-12-01

    Full Text Available We study Einstein’s contributions to thermodynamics and statistical physics and their influence on some fields of physics which have led to current studies on complexity. We focus our attention on the use of fluctuations and entropy as a common framework for light and matter, whcich leds him to some of his fundamental contributions (phtoelectric effect, Brownian motion, specific heat of solids, stimulated light emission, Bose-Einstein condensation. We underline some aspects of Einstein’s research style: extrapolations, analogies, simplifications. We underline the relationship between light and matter as a common link of his researches in statistical physics.Presentamos las contribuciones de Einstein a la termodinámica y la mecánica estadística y su resonancia en ramas de la física que han conducido hasta la consideración actual de lo complejo. Nos referimos especialmente al uso de las fluctuaciones y de la entropía como marco común y nexo de unión entre luz y materia, que le conducen a algunas de sus aportaciones fundamentales (efecto fotoeléctrico, movimiento browniano, calor específico de los sólidos, emisión estimulada de la luz, condensación de Bose-Einstein. Consideramos también algunas facetas del estilo de investigación de Einstein, que se manifiestan con especial claridad en este campo: extrapolaciones, analogías, simplificaciones. Destacamos especialmente la importancia de la relación entre luz y materia en sus investigaciones.

  19. Adrian Stokes and the portrait of Melanie Klein.

    Science.gov (United States)

    Sayers, Janet

    2015-08-01

    This paper focuses on the offer by the art writer Adrian Stokes to commission and pay for a portrait of the psychoanalyst Melanie Klein by the artist William Coldstream. It details some of the precursors of this offer in Stokes's preceding involvement first with Klein and then with Coldstream; her response to this offer; and its outcome and aftermath in Stokes's subsequent writing about Klein and Coldstream. Copyright © 2015 Institute of Psychoanalysis.

  20. CP violation in B decay

    OpenAIRE

    Yamamoto, Hitoshi

    2001-01-01

    We review the physics of CP violation in B decays. After introducing the CKM matrix and how it causes CP violation, we cover three types of CP violation that can occur in B decays: CP violation in mixing, CP violation by mixing-decay interference, and CP violation in decay.

  1. Analyticity estimates for the Navier-Stokes equations

    DEFF Research Database (Denmark)

    Herbst, I.; Skibsted, Erik

    We study spatial analyticity properties of solutions of the Navier-Stokes equation and obtain new growth rate estimates for the analyticity radius. We also study stability properties of strong global solutions of the Navier-Stokes equation with data in and prove a stability result...

  2. Solitons, gauge theories and the 'great Einstein theorem'

    International Nuclear Information System (INIS)

    Dresden, M.; Chen, S.F.

    1976-01-01

    A field theory is said to be of 'Einstein type' if it has the property that the field equations imply the equations of motion. It is known that general relativity is of Einstein type, it is demonstrated here that the Yang-Mills gauge theory is of Einstein type. The relationship between the singularities in the solutions of the field equations and soliton type is analyzed. (Auth.)

  3. Usng subjective percentiles and test data for estimating fragility functions

    International Nuclear Information System (INIS)

    George, L.L.; Mensing, R.W.

    1981-01-01

    Fragility functions are cumulative distribution functions (cdfs) of strengths at failure. They are needed for reliability analyses of systems such as power generation and transmission systems. Subjective opinions supplement sparse test data for estimating fragility functions. Often the opinions are opinions on the percentiles of the fragility function. Subjective percentiles are likely to be less biased than opinions on parameters of cdfs. Solutions to several problems in the estimation of fragility functions are found for subjective percentiles and test data. How subjective percentiles should be used to estimate subjective fragility functions, how subjective percentiles should be combined with test data, how fragility functions for several failure modes should be combined into a composite fragility function, and how inherent randomness and uncertainty due to lack of knowledge should be represented are considered. Subjective percentiles are treated as independent estimates of percentiles. The following are derived: least-squares parameter estimators for normal and lognormal cdfs, based on subjective percentiles (the method is applicable to any invertible cdf); a composite fragility function for combining several failure modes; estimators of variation within and between groups of experts for nonidentically distributed subjective percentiles; weighted least-squares estimators when subjective percentiles have higher variation at higher percents; and weighted least-squares and Bayes parameter estimators based on combining subjective percentiles and test data. 4 figures, 2 tables

  4. The Einstein-Vlasov System/Kinetic Theory

    Directory of Open Access Journals (Sweden)

    Håkan Andréasson

    2002-12-01

    Full Text Available The main purpose of this article is to provide a guide to theorems on global properties of solutions to the Einstein-Vlasov system. This system couples Einstein's equations to a kinetic matter model. Kinetic theory has been an important field of research during several decades in which the main focus has been on nonrelativistic and special relativistic physics, i.e., to model the dynamics of neutral gases, plasmas, and Newtonian self-gravitating systems. In 1990, Rendall and Rein initiated a mathematical study of the Einstein-Vlasov system. Since then many theorems on global properties of solutions to this system have been established. The Vlasov equation describes matter phenomenologically, and it should be stressed that most of the theorems presented in this article are not presently known for other such matter models (i.e., fluid models. This paper gives introductions to kinetic theory in non-curved spacetimes and then the Einstein-Vlasov system is introduced. We believe that a good understanding of kinetic theory in non-curved spacetimes is fundamental to good comprehension of kinetic theory in general relativity.

  5. Sky surveys with Einstein

    International Nuclear Information System (INIS)

    Gioia, I.M.

    1990-01-01

    Since the early times after the launch of the Einstein Observatory, systematic studies of serendipitous Einstein x-ray sources have been carried out by several observers with interests in both galactic and extragalactic astronomy. The majority of these studies were not surveys in the strict sense of the word: in several cases no analyses requiring flux completeness were performed. However, these systematic searches for sources added much to our knowledge of the behaviour in the X-ray domain of the different classes of astronomical objects and in many instances led to the study of their properties at different wavebands. (author)

  6. Einstein and modern cosmology

    International Nuclear Information System (INIS)

    Stabell, R.

    1979-01-01

    Einstein applied his gravitation theory to a universe model with positively curved space in 1917. In order to maintain a static universe he introduced the cosmological constant, which in the light of later nonstatic universe models, he described as his life's greatest mistake. The best known such model is the Einstein-de Sitter model, which is here discussed in some detail. The 'big bang' theory is also discussed leading to the cosmic background radiation. The early phase of the 'big bang' cosmology, the first ten seconds, and the first minutes are discussed, leading to the transparent stage. (JIW)

  7. The intellectual quadrangle: Mach-Boltzmann-Planck-Einstein

    International Nuclear Information System (INIS)

    Broda, E.

    1981-01-01

    These four men were influential in the transition from classical to modern physics. They interacted as scientists, often antagonistically. Thus Boltzmann was the greatest champion of the atom, while Mach remained unconvinced all his life. As a aphysicist, Einstein was greatly influenced by both Mach and Boltzmann, although Mach in the end rejected relativity as well. Because of his work on statistical mechanics, fluctuations, and quantum theory, Einstein has been called the natural successor to Boltzmann. Planck also was influenced by Mach at first. Hence he and Boltzmann were adversaries antil Planck converted to atomistics in 1900 and used the statistical interpretation of entropy to establish his radiation law. Planck accepted relativity early, but in quantum theory he was for a long time partly opposed to Einstein, and vice versa - Einstein considered Planck's derivation of his radiation law as unsound, while Planck could not accept the light quantum. In the case of all four physicists, science was interwoven with philosophy. Boltzmann consistently fought Mach's positivism, while Planck and Einstein moved from positivism to realism. All were also, though in very different ways, actively interested in public affairs. (orig.)

  8. Molecular characterization of X chromosome fragility in idiopathic ...

    African Journals Online (AJOL)

    Heba Alla Hosny Omar

    2015-11-23

    Nov 23, 2015 ... Frequency of fragile X syndrome among male siblings and relatives of mentally retarded patients ... hence the wide clinical spectrum of disorders caused by this ... fragile X syndrome, autism and other less well-characterized.

  9. Trio Fragile / Olga Kaljundi

    Index Scriptorium Estoniae

    Kaljundi, Olga, 1941-2001

    1998-01-01

    Tallinna Vene Draamateatri galeriis esinenud trupi "Trio Fragile" vernissaazhist. Trio loomingust ja osalejatest : kahe muusiku seltskonnas esineb ka 1984.a. Kunstiülikooli lõpetanud kunstnik Tõnu Talve.

  10. How History Helped Einstein in Special Relativity

    Science.gov (United States)

    Martinez, Alberto

    2013-04-01

    I will discuss how the German intellectual movement known as ``critical history'' motivated several physicists in the late 1900s to radically analyze the fundamental principles of mechanics, leading eventually to Einstein's special theory of relativity. Eugen Karl Dühring, Johann Bernhard Stallo, Ludwig Lange, and Ernst Mach wrote critical histories of mechanics, some of which emphasized notions of relativity and observation, in opposition to old metaphysical concepts that seemed to infect the foundations of physics. This strand of critical history included the ``genetic method'' of analyzing how concepts develop over time, in our minds, by way of ordinary experiences, which by 1904 was young Albert Einstein's favorite approach for examining fundamental notions. Thus I will discuss how history contributed in Einstein's path to relativity, as well as comment more generally on Einstein's views on history.

  11. Development of Einstein's general theory of relativity

    International Nuclear Information System (INIS)

    Datta, B.K.

    1980-01-01

    Starting from Poincare's Lorentz-invariant theory of gravity formulated in 1906, development of Einstein's general theory of relativity during 1906-1916 is discussed. Three stages in this development are recognised. In the first stage during 1907-1914, Einstein tried to extend the relativity principle of uniform motion to the frames in non-uniform motion. For this purpose, he introduced the principle of equivalence which made it possible to calculate the effect of homogeneous gravitational field on arbitrary physical processes. During the second stage comprising years 1912-1914 overlapping the first stage, Einstein and Grossmann were struggling to translate physical postulates into the language of the absolute differential calculus. In the period 1915-1916, Einstein formulated the field equations of general relativity. While discussing these developmental stages, theories of gravitation formulated by Abraham, Nordstroem and Mie are also discussed. (M.G.B.)

  12. Ehrenfest en Einstein. Menselijke katalysator van het heldere denken

    Directory of Open Access Journals (Sweden)

    Marijn J. Hollestelle

    2016-10-01

    Full Text Available Ehrenfest and EinsteinEhrenfest and Einstein met just before Ehrenfest became professor at Leiden University. They had much in common and became best friends. Ehrenfest shed light on some problematic aspects of Einstein’s work and during the years acted as an important sparring partner for Einstein. Ehrenfest also explained difficult aspects of Einstein’s work to the physics community. He set others on the track of working on general relativity and made Leiden an international centre for these developments during the years 1912–1920. Ehrenfest made sure Einstein was appointed part-time professor at Leiden, from which Leiden physics profited. He also aided Bohr and Einstein during their notorious debates. Ehrenfest struggled with depression his whole life. The rapid developments and mathematicising of quantum physics, Hitler’s appointment as Reichs Chancellor, money and marriage problems worsened his depressions. In 1933 Ehrenfest committed suicide, and Einstein moved to the United States and away from the study on quantum physics.

  13. Ferroelectricity by Bose-Einstein condensation in a quantum magnet.

    Science.gov (United States)

    Kimura, S; Kakihata, K; Sawada, Y; Watanabe, K; Matsumoto, M; Hagiwara, M; Tanaka, H

    2016-09-26

    The Bose-Einstein condensation is a fascinating phenomenon, which results from quantum statistics for identical particles with an integer spin. Surprising properties, such as superfluidity, vortex quantization or Josephson effect, appear owing to the macroscopic quantum coherence, which spontaneously develops in Bose-Einstein condensates. Realization of Bose-Einstein condensation is not restricted in fluids like liquid helium, a superconducting phase of paired electrons in a metal and laser-cooled dilute alkali atoms. Bosonic quasi-particles like exciton-polariton and magnon in solids-state systems can also undergo Bose-Einstein condensation in certain conditions. Here, we report that the quantum coherence in Bose-Einstein condensate of the magnon quasi particles yields spontaneous electric polarization in the quantum magnet TlCuCl 3 , leading to remarkable magnetoelectric effect. Very soft ferroelectricity is realized as a consequence of the O(2) symmetry breaking by magnon Bose-Einstein condensation. The finding of this ferroelectricity will open a new window to explore multi-functionality of quantum magnets.

  14. Attentional Set-Shifting in Fragile X Syndrome

    Science.gov (United States)

    Van der Molen, M. J. W.; Van der Molen, M. W.; Ridderinkhof, K. R.; Hamel, B. C. J.; Curfs, L. M. G.; Ramakers, G. J. A.

    2012-01-01

    The ability to flexibly adapt to the changing demands of the environment is often reported as a core deficit in fragile X syndrome (FXS). However, the cognitive processes that determine this attentional set-shifting deficit remain elusive. The present study investigated attentional set-shifting ability in fragile X syndrome males with the…

  15. 48 CFR 2803.104-10 - Violations or possible violations.

    Science.gov (United States)

    2010-10-01

    ... General IMPROPER BUSINESS PRACTICES AND PERSONAL CONFLICTS OF INTEREST Safeguards 2803.104-10 Violations... action to be taken. The types of actions that would normally be taken when a violation has occurred that...

  16. Improved Iris Recognition through Fusion of Hamming Distance and Fragile Bit Distance.

    Science.gov (United States)

    Hollingsworth, Karen P; Bowyer, Kevin W; Flynn, Patrick J

    2011-12-01

    The most common iris biometric algorithm represents the texture of an iris using a binary iris code. Not all bits in an iris code are equally consistent. A bit is deemed fragile if its value changes across iris codes created from different images of the same iris. Previous research has shown that iris recognition performance can be improved by masking these fragile bits. Rather than ignoring fragile bits completely, we consider what beneficial information can be obtained from the fragile bits. We find that the locations of fragile bits tend to be consistent across different iris codes of the same eye. We present a metric, called the fragile bit distance, which quantitatively measures the coincidence of the fragile bit patterns in two iris codes. We find that score fusion of fragile bit distance and Hamming distance works better for recognition than Hamming distance alone. To our knowledge, this is the first and only work to use the coincidence of fragile bit locations to improve the accuracy of matches.

  17. High functioning male with fragile X syndrome and fragile X-associated tremor/ataxia syndrome.

    Science.gov (United States)

    Basuta, Kirin; Schneider, Andrea; Gane, Louise; Polussa, Jonathan; Woodruff, Bryan; Pretto, Dalyir; Hagerman, Randi; Tassone, Flora

    2015-09-01

    Fragile X syndrome (FXS) affects individuals with more than 200 CGG repeats (full mutation) in the fragile X mental retardation 1 (FMR1) gene. Those born with FXS experience cognitive and social impairments, developmental delays, and some features of autism spectrum disorders. Carriers of a premutation (55-200 CGG repeats) are generally not severely affected early in life; however, are at high risk of developing the late onset neurodegenerative disorder, Fragile X-associated Tremor/Ataxia Syndrome (FXTAS), or Fragile X-associated Primary Ovarian Insufficiency (FXPOI), and may have other medical conditions such as developmental delay, autism spectrum disorders, hypertension, anxiety, and immune-mediated disorders. Here we present a case of a 58-year-old man with a borderline IQ, average memory skills, and executive function deficits. He met criteria for multiple psychiatric diagnoses and presented with tremor and ataxia, meeting criteria for FXTAS. Molecular testing unveiled a completely unmethylated FMR1 full mutation in peripheral blood mononucleated cells with elevated FMR1 mRNA and premutation alleles of different sizes in two other tissues (primary fibroblasts and sperm), indicating the presence of allele instability based on both inter- and intra-tissue mosaicism. The observation of FXTAS in this case of a full mutation mosaic man suggests that the pathogenic mechanism underlying this disorder is not observed exclusively in premutation carriers as it was originally thought. The concomitant presence of features of FXS and late onset neurological deterioration with probable FXTAS likely result from a combined molecular pathology of elevated FMR1 mRNA levels, a molecular hallmark of FXTAS and low FMRP expression that leads to FXS. © 2015 Wiley Periodicals, Inc.

  18. Fragility correlates thermodynamic and kinetic properties of glass forming liquids

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, C.Narayana [Maharani’s Science College for Women, Bangalore 560001 (India); Viswanatha, R.; Chethana, B.K. [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India); Gowda, V.C.Veeranna [Government First Grade College, Jayanagara, Bangalore 560070 (India); Rao, K.J., E-mail: kalyajrao@yahoo.co.in [Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India)

    2015-03-15

    Graphical abstract: The suggested new fragility parameter correlates viscosity and configurational entropy. - Highlights: • A new fragility function, F=ΔT/ΔC{sub p}×C{sub p}{sup l}/T{sub g} has been proposed. • A three parameter viscosity function using the new F reproduces Angell fragility plot. • A new ΔC{sub p} function is derived which directly relates Adam–Gibbs function with the fragility based viscosity function. - Abstract: In our earlier communication we proposed a simple fragility determining function, ([NBO]/V{sub m}{sup 3}T{sub g}), which we have now used to analyze several glass systems using available thermal data. A comparison with similar fragility determining function, ΔC{sub p}/C{sub p}{sup l}, introduced by Chryssikos et al. in their investigation of lithium borate glasses has also been performed and found to be more convenient quantity for discussing fragilities. We now propose a new function which uses both ΔC{sub p} and ΔT and which gives a numerical fragility parameter, F whose value lies between 0 and 1 for glass forming liquids. F can be calculated through the use of measured thermal parameters ΔC{sub p}, C{sub p}{sup l}, T{sub g} and T{sub m}. Use of the new fragility values in reduced viscosity equation reproduces the whole range of viscosity curves of the Angell plot. The reduced viscosity equation can be directly compared with the Adam–Gibbs viscosity equation and a heat capacity function can be formulated which reproduces satisfactorily the ΔC{sub p} versus ln(T{sub r}) curves and hence the configurational entropy.

  19. Small vacuum energy from small equivalence violation in scalar gravity

    International Nuclear Information System (INIS)

    Agrawal, Prateek; Sundrum, Raman

    2017-01-01

    The theory of scalar gravity proposed by Nordström, and refined by Einstein and Fokker, provides a striking analogy to general relativity. In its modern form, scalar gravity appears as the low-energy effective field theory of the spontaneous breaking of conformal symmetry within a CFT, and is AdS/CFT dual to the original Randall-Sundrum I model, but without a UV brane. Scalar gravity faithfully exhibits several qualitative features of the cosmological constant problem of standard gravity coupled to quantum matter, and the Weinberg no-go theorem can be extended to this case as well. Remarkably, a solution to the scalar gravity cosmological constant problem has been proposed, where the key is a very small violation of the scalar equivalence principle, which can be elegantly formulated as a particular type of deformation of the CFT. In the dual AdS picture this involves implementing Goldberger-Wise radion stabilization where the Goldberger-Wise field is a pseudo-Nambu Goldstone boson. In quantum gravity however, global symmetries protecting pNGBs are not expected to be fundamental. We provide a natural six-dimensional gauge theory origin for this global symmetry and show that the violation of the equivalence principle and the size of the vacuum energy seen by scalar gravity can naturally be exponentially small. Our solution may be of interest for study of non-supersymmetric CFTs in the spontaneously broken phase.

  20. Small vacuum energy from small equivalence violation in scalar gravity

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, Prateek [Department of Physics, Harvard University,Cambridge, MA 02138 (United States); Sundrum, Raman [Department of Physics, University of Maryland,College Park, MD 20742 (United States)

    2017-05-29

    The theory of scalar gravity proposed by Nordström, and refined by Einstein and Fokker, provides a striking analogy to general relativity. In its modern form, scalar gravity appears as the low-energy effective field theory of the spontaneous breaking of conformal symmetry within a CFT, and is AdS/CFT dual to the original Randall-Sundrum I model, but without a UV brane. Scalar gravity faithfully exhibits several qualitative features of the cosmological constant problem of standard gravity coupled to quantum matter, and the Weinberg no-go theorem can be extended to this case as well. Remarkably, a solution to the scalar gravity cosmological constant problem has been proposed, where the key is a very small violation of the scalar equivalence principle, which can be elegantly formulated as a particular type of deformation of the CFT. In the dual AdS picture this involves implementing Goldberger-Wise radion stabilization where the Goldberger-Wise field is a pseudo-Nambu Goldstone boson. In quantum gravity however, global symmetries protecting pNGBs are not expected to be fundamental. We provide a natural six-dimensional gauge theory origin for this global symmetry and show that the violation of the equivalence principle and the size of the vacuum energy seen by scalar gravity can naturally be exponentially small. Our solution may be of interest for study of non-supersymmetric CFTs in the spontaneously broken phase.

  1. Developing empirical collapse fragility functions for global building types

    Science.gov (United States)

    Jaiswal, K.; Wald, D.; D'Ayala, D.

    2011-01-01

    Building collapse is the dominant cause of casualties during earthquakes. In order to better predict human fatalities, the U.S. Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER) program requires collapse fragility functions for global building types. The collapse fragility is expressed as the probability of collapse at discrete levels of the input hazard defined in terms of macroseismic intensity. This article provides a simple procedure for quantifying collapse fragility using vulnerability criteria based on the European Macroseismic Scale (1998) for selected European building types. In addition, the collapse fragility functions are developed for global building types by fitting the beta distribution to the multiple experts’ estimates for the same building type (obtained from EERI’s World Housing Encyclopedia (WHE)-PAGER survey). Finally, using the collapse probability distributions at each shaking intensity level as a prior and field-based collapse-rate observations as likelihood, it is possible to update the collapse fragility functions for global building types using the Bayesian procedure.

  2. Treatment of Fragile X Syndrome with a Neuroactive Steroid

    Science.gov (United States)

    2013-08-01

    Fulks JL, O’Bryhim BE et al (2010) Dopamine release and uptake impairments and behavioral alterations observed in mice that model fragile x mental...D2 dopamine receptor agonist. J Cogn Neurosci 4(1):58–68 Luo Y, Shan G et al (2010) Fragile x mental retardation protein regulates proliferation and...AD_________________ Award Number: W81XWH-11-1-0626 TITLE: Treatment of Fragile X Syndrome with a

  3. Nuclear Power Plant Mechanical Component Flooding Fragility Experiments Status

    Energy Technology Data Exchange (ETDEWEB)

    Pope, C. L. [Idaho State Univ., Pocatello, ID (United States); Savage, B. [Idaho State Univ., Pocatello, ID (United States); Johnson, B. [Idaho State Univ., Pocatello, ID (United States); Muchmore, C. [Idaho State Univ., Pocatello, ID (United States); Nichols, L. [Idaho State Univ., Pocatello, ID (United States); Roberts, G. [Idaho State Univ., Pocatello, ID (United States); Ryan, E. [Idaho State Univ., Pocatello, ID (United States); Suresh, S. [Idaho State Univ., Pocatello, ID (United States); Tahhan, A. [Idaho State Univ., Pocatello, ID (United States); Tuladhar, R. [Idaho State Univ., Pocatello, ID (United States); Wells, A. [Idaho State Univ., Pocatello, ID (United States); Smith, C. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-07-24

    This report describes progress on Nuclear Power Plant mechanical component flooding fragility experiments and supporting research. The progress includes execution of full scale fragility experiments using hollow-core doors, design of improvements to the Portal Evaluation Tank, equipment procurement and initial installation of PET improvements, designation of experiments exploiting the improved PET capabilities, fragility mathematical model development, Smoothed Particle Hydrodynamic simulations, wave impact simulation device research, and pipe rupture mechanics research.

  4. Seismic fragility of nuclear power plant components. Phase I

    International Nuclear Information System (INIS)

    Bandyopadhyay, K.K.; Hofmayer, C.H.

    1986-06-01

    As part of the Component Fragility Research Program, sponsored by the US Nuclear Regulatory Commission, BNL is involved in establishing seismic fragility levels for various nuclear power plant equipment by identifying, collecting and analyzing existing test data from various sources. In Phase I of this program, BNL has reviewed approximately seventy test reports to collect fragility or high level test data for switchgears, motor control centers and similar electrical cabinets, valve actuators and numerous electrical devices of various manufacturers and models. This report provides an assessment and evaluation of the data collected in Phase I. The fragility data for medium voltage and low voltage switchgears and motor control centers are analyzed using the test response spectra (TRS) as a measure of the fragility level. The analysis reveals that fragility levels can best be described by a group of TRS curves corresponding to various failure modes. The lower-bound curve indicates the initiation of malfunctioning or structural damage; whereas, the upper-bound curve corresponds to overall failure of the equipment based on known failure modes. High level test data for some components are included in the report. These data indicate that some components are inherently strong and do not exhibit any failure mode even when tested at the vibration limit of a shake table. The common failure modes are identified in the report. The fragility levels determined in this report have been compared with those used in the PRA and Seismic Margin Studies. It appears that the BNL data better correlate with the HCLPF (High Confidence of a Low Probability of Failure) level used in Seismic Margin Studies and can improve this level as high as 60% for certain applications. Specific recommendations are provided for proper application of BNL fragility data to other studies

  5. Einstein, Ethics and the Atomic Bomb

    Science.gov (United States)

    Rife, Patricia

    2005-03-01

    Einstein voiced his ethical views against war as well as fascism via venues and alliances with a variety of organizations still debated today. In 1939, he signed a letter to President Roosevelt (drafted by younger colleagues Szilard, Wigner and others) warning the U.S.government about the danger of Nazi Germany gaining control of uranium in the Belgian-controlled Congo in order to develop atomic weapons, based on the discovery of fission by Otto Hahn and Lise Meitner. In 1945, he became a member of the Princeton-based ``Emergency Committee for Atomic Scientists'' organized by Bethe, Condon, Bacher, Urey, Szilard and Weisskopf. Rare Einstein slides will illustrate Dr.Rife's presentation on Albert Einstein's philosophic and ethical convictions about peace, and public stance against war (1914-1950).

  6. Classes of exact Einstein Maxwell solutions

    Science.gov (United States)

    Komathiraj, K.; Maharaj, S. D.

    2007-12-01

    We find new classes of exact solutions to the Einstein Maxwell system of equations for a charged sphere with a particular choice of the electric field intensity and one of the gravitational potentials. The condition of pressure isotropy is reduced to a linear, second order differential equation which can be solved in general. Consequently we can find exact solutions to the Einstein Maxwell field equations corresponding to a static spherically symmetric gravitational potential in terms of hypergeometric functions. It is possible to find exact solutions which can be written explicitly in terms of elementary functions, namely polynomials and product of polynomials and algebraic functions. Uncharged solutions are regainable with our choice of electric field intensity; in particular we generate the Einstein universe for particular parameter values.

  7. Observation of correlated anti-Stokes emissions by multiwave mixing in sodium vapor

    International Nuclear Information System (INIS)

    Motomura, Koji; Tsukamoto, Mayumi; Wakiyama, Akira; Harada, Ken-ichi; Mitsunaga, Masaharu

    2005-01-01

    We study experimentally nonlinear optical processes in which Stokes and anti-Stokes fields build up under strong, resonant, counterpropagating pump laser excitation in atomic sodium vapor. We find that, at some pump frequency, two off-axis anti-Stokes emissions propagating along reflection-symmetric directions are strongly temporally correlated, with a correlation time of 0.5 μs and a correlation range of 1 mrad. It is shown by the numerical analysis based on six-wave mixing process involving pump, Stokes, and anti-Stokes waves in the forward and the backward directions that such correlated anti-Stokes emissions are possible when the medium is opaque for the Stokes field and transparent for the anti-Stokes field. Possibilities of quantum correlation for entangled photon generation using this system are discussed

  8. Kerr black holes are not fragile

    Energy Technology Data Exchange (ETDEWEB)

    McInnes, Brett, E-mail: matmcinn@nus.edu.sg [Centro de Estudios Cientificos (CECs), Valdivia (Chile); National University of Singapore (Singapore)

    2012-04-21

    Certain AdS black holes are 'fragile', in the sense that, if they are deformed excessively, they become unstable to a fundamental non-perturbative stringy effect analogous to Schwinger pair-production [of branes]. Near-extremal topologically spherical AdS-Kerr black holes, which are natural candidates for string-theoretic models of the very rapidly rotating black holes that have actually been observed to exist, do represent a very drastic deformation of the AdS-Schwarzschild geometry. One therefore has strong reason to fear that these objects might be 'fragile', which in turn could mean that asymptotically flat rapidly rotating black holes might be fragile in string theory. Here we show that this does not happen: despite the severe deformation implied by near-extremal angular momenta, brane pair-production around topologically spherical AdS-Kerr-Newman black holes is always suppressed.

  9. Einstein wrote back my life in physics

    CERN Document Server

    Moffat, John W

    2012-01-01

    John W. Moffat was a poor student of math and science. That is, until he read Einstein's famous paper on general relativity. Realizing instantly that he had an unusual and unexplained aptitude for understanding the complex physics described in the paper, Moffat wrote a letter to Einstein that would change the course of his life. Einstein Wrote Back tells the story of Moffat's unusual entry into the world of academia and documents his career at the frontlines of twentieth-century physics as he worked and associated with some of the greatest minds in scientific history, including Niels Bohr,

  10. Einstein constraints in the Yang-Mills form

    International Nuclear Information System (INIS)

    Ashtekar, A.

    1987-01-01

    It is pointed out that constraints of Einstein's theory play a powerful role in both classical and quantum theory because they generate motions in spacetime, rather than in an internal space. New variables are then introduced on the Einstein phase space in terms of which constraints simplify considerably. In particular, the use of these variables enables one to imbed the constraint surface of Einstein's theory into that of Yang-Mills. The imbedding suggests new lines of attack to a number of problems in classical and quantum gravity and provides new concepts and tools to investigate the microscopic structure of space-time geometry

  11. Effective equivalence of the Einstein-Cartan and Einstein theories of gravity

    International Nuclear Information System (INIS)

    Nester, J.M.

    1977-01-01

    I prove that, for any choice of minimally coupled source field Lagrangian for the Einstein-Cartan-Sciama-Kibble theory of gravity, there exists a related minimally coupled source field Lagrangian for the Einstein theory which produces the same field equations for the metric and source field. By using a standard first-order form for source Lagrangians, the converse is also demonstrated. This establishes a one-to-one correspondence between source Lagrangians for the two theories which clearly reveals their similarities and their differences. Because of this ''equivalence,'' one can view either theory, in terms of the other, as minimal coupling for a related Minkowski source Lagrangian or as nonminimal coupling for the same Minkowski source Lagrangian. Consequently the two theories are, in this sense, indistinguishable. Some other implications of this ''equivalence'' are discussed

  12. Self Completeness of Einstein Gravity

    CERN Document Server

    Dvali, Gia

    2010-01-01

    We argue, that in Einsteinian gravity the Planck length is the shortest length of nature, and any attempt of resolving trans-Planckian physics bounces back to macroscopic distances due to black hole formation. In Einstein gravity trans-Planckian propagating quantum degrees of freedom cannot exist, instead they are equivalent to the classical black holes that are fully described by lighter infra-red degrees of freedom and give exponentially-soft contribution into the virtual processes. Based on this property we argue that pure-Einstein (super)gravity and its high-dimensional generalizations are self-complete in deep-UV, but not in standard Wilsonian sense. We suggest that certain strong-coupling limit of string theory is built-in in pure Einstein gravity, whereas the role of weakly-coupled string theory limit is to consistently couple gravity to other particle species, with their number being set by the inverse string coupling. We also discuss some speculative ideas generalizing the notion of non-Wilsonian sel...

  13. Tirilazad mesylate protects stored erythrocytes against osmotic fragility.

    Science.gov (United States)

    Epps, D E; Knechtel, T J; Bacznskyj, O; Decker, D; Guido, D M; Buxser, S E; Mathews, W R; Buffenbarger, S L; Lutzke, B S; McCall, J M

    1994-12-01

    The hypoosmotic lysis curve of freshly collected human erythrocytes is consistent with a single Gaussian error function with a mean of 46.5 +/- 0.25 mM NaCl and a standard deviation of 5.0 +/- 0.4 mM NaCl. After extended storage of RBCs under standard blood bank conditions the lysis curve conforms to the sum of two error functions instead of a possible shift in the mean and a broadening of a single error function. Thus, two distinct sub-populations with different fragilities are present instead of a single, broadly distributed population. One population is identical to the freshly collected erythrocytes, whereas the other population consists of osmotically fragile cells. The rate of generation of the new, osmotically fragile, population of cells was used to probe the hypothesis that lipid peroxidation is responsible for the induction of membrane fragility. If it is so, then the antioxidant, tirilazad mesylate (U-74,006f), should protect against this degradation of stored erythrocytes. We found that tirilazad mesylate, at 17 microM (1.5 mol% with respect to membrane lecithin), retards significantly the formation of the osmotically fragile RBCs. Concomitantly, the concentration of free hemoglobin which accumulates during storage is markedly reduced by the drug. Since the presence of the drug also decreases the amount of F2-isoprostanes formed during the storage period, an antioxidant mechanism must be operative. These results demonstrate that tirilazad mesylate significantly decreases the number of fragile erythrocytes formed during storage in the blood bank.

  14. Albert Einstein and 20th century's physics

    International Nuclear Information System (INIS)

    Zajac, R.

    1979-01-01

    Albert Einstein's teaching and his three fundamental works are discussed dealing with the molecular theory of heat applied to the motion of suspended particles in liquids at rest, the photoelectric effect, and the theory of relativity. Albert Einstein's impact on contemporary physics is evaluated. (J.P.)

  15. Improved Erythrocyte Osmotic Fragility and Packed Cell Volume ...

    African Journals Online (AJOL)

    Improved Erythrocyte Osmotic Fragility and Packed Cell Volume following administration of Aloe barbadensis Juice Extract in Rats. ... Abstract. Aloe barbadensis is a popular house plant that has a long history of a multipurpose folk remedy. ... Keywords: osmotic fragility, packed cell volume, haemoglobin, Aloe vera ...

  16. Spectroscopy of dark soliton states in Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Bongs, K; Burger, S; Hellweg, D; Kottke, M; Dettmer, S; Rinkleff, T; Cacciapuoti, L; Arlt, J; Sengstock, K; Ertmer, W

    2003-01-01

    Experimental and numerical studies of the velocity field of dark solitons in Bose-Einstein condensates are presented. The formation process after phase imprinting as well as the propagation of the emerging soliton are investigated using spatially resolved Bragg spectroscopy of soliton states in Bose-Einstein condensates of 87 Rb. A comparison of experimental data to results from numerical simulations of the Gross-Pitaevskii equation clearly identifies the flux underlying a dark soliton propagating in a Bose-Einstein condensate. The results allow further optimization of the phase imprinting method for creating collective excitations of Bose-Einstein condensates

  17. CP violation and long-distance effects in radiative B decays

    International Nuclear Information System (INIS)

    Leusen, J. van

    2004-01-01

    In this thesis the CP violating asymmetries in the decays anti B 0 →π + π - , anti B 0 →ρ 0 γ, anti B 0 →π + π - γ, and anti B 0 →ρ 0 e + e - are calculated on the base of the →d transition and the CKM-mixing. (HSI) In the present thesis rare decays from the range of B meson physics were discussed. Thereby the main aim was put on decays with b→d transitions. The models were studied concerning branching ratios, CP asymmetries, Stokes-vector components, and forward-backward asymmetries. For the decay anti B 0 →π + π - the model from the QCD factorization was discussed and compared with the actual results from the experiments. Furthermore the decay channels anti B 0 →ρ 0 γ, anti B 0 →π + π - γ, and anti B 0 →ρ 0 e + e - were studied

  18. Test of the Equivalence Principle in an Einstein Elevator

    Science.gov (United States)

    Shapiro, Irwin I.; Glashow, S.; Lorenzini, E. C.; Cosmo, M. L.; Cheimets, P. N.; Finkelstein, N.; Schneps, M.

    2005-01-01

    This Annual Report illustrates the work carried out during the last grant-year activity on the Test of the Equivalence Principle in an Einstein Elevator. The activity focused on the following main topics: (1) analysis and conceptual design of a detector configuration suitable for the flight tests; (2) development of techniques for extracting a small signal from data strings with colored and white noise; (3) design of the mechanism that spins and releases the instrument package inside the cryostat; and (4) experimental activity carried out by our non-US partners (a summary is shown in this report). The analysis and conceptual design of the flight-detector (point 1) was focused on studying the response of the differential accelerometer during free fall, in the presence of errors and precession dynamics, for various detector's configurations. The goal was to devise a detector configuration in which an Equivalence Principle violation (EPV) signal at the sensitivity threshold level can be successfully measured and resolved out of a much stronger dynamics-related noise and gravity gradient. A detailed analysis and comprehensive simulation effort led us to a detector's design that can accomplish that goal successfully.

  19. Einstein gravity 3-point functions from conformal field theory

    Science.gov (United States)

    Afkhami-Jeddi, Nima; Hartman, Thomas; Kundu, Sandipan; Tajdini, Amirhossein

    2017-12-01

    We study stress tensor correlation functions in four-dimensional conformal field theories with large N and a sparse spectrum. Theories in this class are expected to have local holographic duals, so effective field theory in anti-de Sitter suggests that the stress tensor sector should exhibit universal, gravity-like behavior. At the linearized level, the hallmark of locality in the emergent geometry is that stress tensor three-point functions 〈 T T T 〉, normally specified by three constants, should approach a universal structure controlled by a single parameter as the gap to higher spin operators is increased. We demonstrate this phenomenon by a direct CFT calculation. Stress tensor exchange, by itself, violates causality and unitarity unless the three-point functions are carefully tuned, and the unique consistent choice exactly matches the prediction of Einstein gravity. Under some assumptions about the other potential contributions, we conclude that this structure is universal, and in particular, that the anomaly coefficients satisfy a ≈ c as conjectured by Camanho et al. The argument is based on causality of a four-point function, with kinematics designed to probe bulk locality, and invokes the chaos bound of Maldacena, Shenker, and Stanford.

  20. Stationary axisymmetric Einstein--Maxwell field equations

    International Nuclear Information System (INIS)

    Catenacci, R.; Diaz Alonso, J.

    1976-01-01

    We show the existence of a formal identity between Einstein's and Ernst's stationary axisymmetric gravitational field equations and the Einstein--Maxwell and the Ernst equations for the electrostatic and magnetostatic axisymmetric cases. Our equations are invariant under very simple internal symmetry groups, and one of them appears to be new. We also obtain a method for associating two stationary axisymmetric vacuum solutions with every electrostatic known

  1. What about Albert Einstein? Using Biographies to Promote Students' Scientific Thinking

    Science.gov (United States)

    Fingon, Joan C.; Fingon, Shallon D.

    2009-01-01

    Who hasn't heard of Einstein? Science educators everywhere are familiar with Einstein's genius and general theory of relativity. Students easily recognize Einstein's image by his white flyaway hair and bushy mustache. It is well known that Einstein was a brilliant physicist and an abstract thinker who often used his creativity and imagination in…

  2. The correlation between fragility, density, and atomic interaction in glass-forming liquids.

    Science.gov (United States)

    Wang, Lijin; Guan, Pengfei; Wang, W H

    2016-07-21

    The fragility that controls the temperature-dependent viscous properties of liquids as the glass transition is approached, in various glass-forming liquids with different softness of the repulsive part of atomic interactions at different densities, is investigated by molecular dynamic simulations. We show that the landscape of fragility in purely repulsive systems can be separated into three regions denoted as RI, RII, and RIII, respectively, with qualitatively disparate dynamic behaviors: RI which can be described by "softness makes strong glasses," RII where fragility is independent of softness and can only be tuned by density, and RIII with constant fragility, suggesting that density plays an unexpected role for understanding the repulsive softness dependence of fragility. What is more important is that we unify the long-standing inconsistence with respect to the repulsive softness dependence of fragility by observing that a glass former can be tuned more fragile if nonperturbative attraction is added into it. Moreover, we find that the vastly dissimilar influences of attractive interaction on fragility could be estimated from the structural properties of related zero-temperature glasses.

  3. Classes of general axisymmetric solutions of Einstein-Maxwell equations

    International Nuclear Information System (INIS)

    Krori, K.D.; Choudhury, T.

    1981-01-01

    An exact solution of the Einstein equations for a stationary axially symmetric distribution of mass composed of all types of multipoles is obtained. Following Ernst (1968), from this vacuum solution the corresponding solution of the coupled Einstein-Maxwell equations is derived. A solution of Einstein-Maxwell fields for a static axially symmetric system composed of all types of multipoles is also obtained. (author)

  4. Bose-Einstein Condensation

    Indian Academy of Sciences (India)

    absolute zero. These ideas had ... Everybody is talking about Bose-Einstein condensation. This discovery ... needed if we want to find the probability distribution of the x- ... Boltzmann took two approaches to the problem, both of them deep and ...

  5. Component Fragility Research Program: Phase 1 component prioritization

    International Nuclear Information System (INIS)

    Holman, G.S.; Chou, C.K.

    1987-06-01

    Current probabilistic risk assessment (PRA) methods for nuclear power plants utilize seismic ''fragilities'' - probabilities of failure conditioned on the severity of seismic input motion - that are based largely on limited test data and on engineering judgment. Under the NRC Component Fragility Research Program (CFRP), the Lawrence Livermore National Laboratory (LLNL) has developed and demonstrated procedures for using test data to derive probabilistic fragility descriptions for mechanical and electrical components. As part of its CFRP activities, LLNL systematically identified and categorized components influencing plant safety in order to identify ''candidate'' components for future NRC testing. Plant systems relevant to safety were first identified; within each system components were then ranked according to their importance to overall system function and their anticipated seismic capacity. Highest priority for future testing was assigned to those ''very important'' components having ''low'' seismic capacity. This report describes the LLNL prioritization effort, which also included application of ''high-level'' qualification data as an alternate means of developing probabilistic fragility descriptions for PRA applications

  6. Competition between Bose-Einstein Condensation and Spin Dynamics.

    Science.gov (United States)

    Naylor, B; Brewczyk, M; Gajda, M; Gorceix, O; Maréchal, E; Vernac, L; Laburthe-Tolra, B

    2016-10-28

    We study the impact of spin-exchange collisions on the dynamics of Bose-Einstein condensation by rapidly cooling a chromium multicomponent Bose gas. Despite relatively strong spin-dependent interactions, the critical temperature for Bose-Einstein condensation is reached before the spin degrees of freedom fully thermalize. The increase in density due to Bose-Einstein condensation then triggers spin dynamics, hampering the formation of condensates in spin-excited states. Small metastable spinor condensates are, nevertheless, produced, and they manifest in strong spin fluctuations.

  7. Einstein's Mirror

    Science.gov (United States)

    Gjurchinovski, Aleksandar; Skeparovski, Aleksandar

    2008-01-01

    Reflection of light from a plane mirror in uniform rectilinear motion is a century-old problem, intimately related to the foundations of special relativity. The problem was first investigated by Einstein in his famous 1905 paper by using the Lorentz transformations to switch from the mirror's rest frame to the frame where the mirror moves at a…

  8. You err, Einstein.. Newton, Einstein, Heisenberg, and Feynman discuss quantum physics

    International Nuclear Information System (INIS)

    Fritzsch, Harald

    2008-01-01

    Harald Fritzsch and his star physicists Einstein, Heisenberg, and Feynman explain the central concept of nowadays physics, quantum mechanics, without it nothing goes in modern world. And the great Isaac newton puts the questions, which all would put

  9. Theory of a gauge gravitational field at localization of the Einstein group

    International Nuclear Information System (INIS)

    Tunyak, V.N.

    1985-01-01

    Theory of a gauge gravitational field when localizing a group of movements of the Einstein homogeneous static Universe (the R x SO Einstein group (4)) has been formulated. Proceeding from tetrade components of the Einstein Universe the relation between the Riemann metrics and gauge fields of the Einstein group has been established. Metric coherence with torsion transforming to the Kristoffel coherence of the Einstein Universe has been found when switching out gauge fields. It is shown that within the limit of infinite radius of the Einstein Universe curvature the given Einstein-invariant gauge theory transforms to the tetrade gravitation theory with localized triade rotations. Exact solutions in the form of nonsingular cosmological models have been obtained

  10. 48 CFR 903.104-7 - Violations or possible violations.

    Science.gov (United States)

    2010-10-01

    ... violation or possible violation of subsections 27 (a), (b), (c) or (d) of the Office of Federal Procurement... disclosure of proprietary or source selection information is the Assistant General Counsel for Procurement...) and (2) for Headquarters activities is the Agency Ethics Official (Designated Agency Ethics Official...

  11. Molecular characterization of X chromosome fragility in idiopathic ...

    African Journals Online (AJOL)

    Background: Fragile X syndrome (FXS) is the most common form of inherited mental retardation. Frequency of fragile X syndrome among male siblings and relatives of mentally retarded patients is relatively high. Cytogenetic diagnosis of FXS is unreliable since it is ineffective for the diagnosis of premutated males or ...

  12. EINSTEIN EQUATIONS FOR TETRAD FIELDS ECUACIONES DE EINSTEIN PARA CAMPOS TETRADOS

    Directory of Open Access Journals (Sweden)

    Héctor Torres-Silva

    2008-11-01

    Full Text Available Every metric tensor can be expressed by the inner product of tetrad fields. We prove that Einstein's equations for these fields have the same form as the stress-energy tensor of electromagnetism if the total external current . Using the Evans' unified field theory, we show that the true unification of gravity and electromagnetism is with source-free Maxwell equations.Todo tensor métrico puede ser expresado por el producto interno de campos tetrados. Se prueba que las ecuaciones de Einstein para esos campos tienen la misma forma que el tensor electromagnético de momento-energía si la corriente externa total es igual a cero. Usando la teoría de campo unificado de Evans se muestra que la verdadera unificación de la gravedad y el electromagnetismo es con las ecuaciones de Maxwell sin fuentes.

  13. Approximate Stokes Drift Profiles and their use in Ocean Modelling

    Science.gov (United States)

    Breivik, Oyvind; Bidlot, Jea-Raymond; Janssen, Peter A. E. M.; Mogensen, Kristian

    2016-04-01

    Deep-water approximations to the Stokes drift velocity profile are explored as alternatives to the monochromatic profile. The alternative profiles investigated rely on the same two quantities required for the monochromatic profile, viz the Stokes transport and the surface Stokes drift velocity. Comparisons against parametric spectra and profiles under wave spectra from the ERA-Interim reanalysis and buoy observations reveal much better agreement than the monochromatic profile even for complex sea states. That the profiles give a closer match and a more correct shear has implications for ocean circulation models since the Coriolis-Stokes force depends on the magnitude and direction of the Stokes drift profile and Langmuir turbulence parameterizations depend sensitively on the shear of the profile. Of the two Stokes drift profiles explored here, the profile based on the Phillips spectrum is by far the best. In particular, the shear near the surface is almost identical to that influenced by the f-5 tail of spectral wave models. The NEMO general circulation ocean model was recently extended to incorporate the Stokes-Coriolis force along with two other wave-related effects. The ECWMF coupled atmosphere-wave-ocean ensemble forecast system now includes these wave effects in the ocean model component (NEMO).

  14. Fragile-to-fragile liquid transition at Tg and stable-glass phase nucleation rate maximum at the Kauzmann temperature TK

    International Nuclear Information System (INIS)

    Tournier, Robert F.

    2014-01-01

    An undercooled liquid is unstable. The driving force of the glass transition at T g is a change of the undercooled-liquid Gibbs free energy. The classical Gibbs free energy change for a crystal formation is completed including an enthalpy saving. The crystal growth critical nucleus is used as a probe to observe the Laplace pressure change Δp accompanying the enthalpy change −V m ×Δp at T g where V m is the molar volume. A stable glass–liquid transition model predicts the specific heat jump of fragile liquids at T≤T g , the Kauzmann temperature T K where the liquid entropy excess with regard to crystal goes to zero, the equilibrium enthalpy between T K and T g , the maximum nucleation rate at T K of superclusters containing magic atom numbers, and the equilibrium latent heats at T g and T K . Strong-to-fragile and strong-to-strong liquid transitions at T g are also described and all their thermodynamic parameters are determined from their specific heat jumps. The existence of fragile liquids quenched in the amorphous state, which do not undergo liquid–liquid transition during heating preceding their crystallization, is predicted. Long ageing times leading to the formation at T K of a stable glass composed of superclusters containing up to 147 atom, touching and interpenetrating, are evaluated from nucleation rates. A fragile-to-fragile liquid transition occurs at T g without stable-glass formation while a strong glass is stable after transition

  15. Structure of the space of solutions of Einstein's equations II: Several killing fields and the Einstein-Yang-Mills equations

    International Nuclear Information System (INIS)

    Arms, J.M.; Marsden, J.E.; Moncrief, V.

    1982-01-01

    The space of solutions of Einstein's vacuum equations is shown to have conical singularities at each spacetime possessing a compact Cauchy surface of constant mean curvature and a nontrivial set of Killing fields. Similar results are shown for the coupled Einstein-Yang-Mills system. Combined with an appropriate slice theorem, the results show that the space of geometrically equivalent solutions is a stratified manifold with each stratum being a symplectic manifold characterized by the symmetry type of its members. Contents: Introduction 1. The Kuranishi map and its properties. 2. The momentum constraints. 3. The Hamiltonian constraints. 4. The Einstein-Yang-Mills system. 5. Discussion and examples

  16. Invertible chaotic fragile watermarking for robust image authentication

    International Nuclear Information System (INIS)

    Sidiropoulos, Panagiotis; Nikolaidis, Nikos; Pitas, Ioannis

    2009-01-01

    Fragile watermarking is a popular method for image authentication. In such schemes, a fragile signal that is sensitive to manipulations is embedded in the image, so that it becomes undetectable after any modification of the original work. Most algorithms focus either on the ability to retrieve the original work after watermark detection (invertibility) or on detecting which image parts have been altered (localization). Furthermore, the majority of fragile watermarking schemes suffer from robustness flaws. We propose a new technique that combines localization and invertibility. Moreover, watermark dependency on the original image and the non-linear watermark embedding procedure guarantees that no malicious attacks will manage to create information leaks.

  17. Clinical neurogenetics: fragile x-associated tremor/ataxia syndrome.

    Science.gov (United States)

    Hall, Deborah A; O'Keefe, Joan A

    2013-11-01

    This article summarizes the clinical findings, genetics, pathophysiology, and treatment of fragile X-associated tremor ataxia syndrome. The disorder occurs from a CGG repeat (55-200) expansion in the fragile X mental retardation 1 gene. It manifests clinically in kinetic tremor, gait ataxia, and executive dysfunction, usually in older men who carry the genetic abnormality. The disorder has distinct radiographic and pathologic findings. Symptomatic treatment is beneficial in some patients. The inheritance is X-linked and family members may be at risk for other fragile X-associated disorders. This information is useful to neurologists, general practitioners, and geneticists. Copyright © 2013. Published by Elsevier Inc.

  18. Einstein's Years in Switzerland

    Science.gov (United States)

    Plendl, Hans S.

    2005-11-01

    Albert Einstein left Germany, the country of his birth, in 1894 and moved to Switzerland in 1895. He studied, worked and taught there, except for a year's stay in Prague, until1914. That year he returned to Germany, where he lived until his emigration to the United States in 1933. In 1905, while living with his wife Mileva and their first son Hans Albert in Bern and working as a technical expert at the Swiss Patent Office, he published his dissertation on the determination of molecular dimensions, his papers on Brownian Motion that helped to establish the Kinetic Theory of Heat and on the Photo-Electric Effect that validated the Quantum Theory of Light, and the two papers introducing the Special Theory of Relativity. How the young Einstein could help to lay the foundations of these theories while still working on his dissertation, holding a full-time job and helping to raise a family has evoked much discussion among his biographers. In this contribution, the extent to which living within Swiss society and culture could have made this feat possible will be examined. Old and recent photos of places in Switzerland where Einstein has lived and worked will be shown.

  19. What Einstein Can Teach Us about Education

    Science.gov (United States)

    Hayes, Denis

    2007-01-01

    People are more likely to associate Einstein with complex scientific theories and mathematical calculations than with education theory. In fact, Einstein's own experiences of schooling and his reflections on the meaning of life and the significance of education are profound and oddly relevant to the situation that pertains in England today. It is…

  20. From Einstein's theorem to Bell's theorem: a history of quantum non-locality

    Science.gov (United States)

    Wiseman, H. M.

    2006-04-01

    In this Einstein Year of Physics it seems appropriate to look at an important aspect of Einstein's work that is often down-played: his contribution to the debate on the interpretation of quantum mechanics. Contrary to physics ‘folklore’, Bohr had no defence against Einstein's 1935 attack (the EPR paper) on the claimed completeness of orthodox quantum mechanics. I suggest that Einstein's argument, as stated most clearly in 1946, could justly be called Einstein's reality locality completeness theorem, since it proves that one of these three must be false. Einstein's instinct was that completeness of orthodox quantum mechanics was the falsehood, but he failed in his quest to find a more complete theory that respected reality and locality. Einstein's theorem, and possibly Einstein's failure, inspired John Bell in 1964 to prove his reality locality theorem. This strengthened Einstein's theorem (but showed the futility of his quest) by demonstrating that either reality or locality is a falsehood. This revealed the full non-locality of the quantum world for the first time.

  1. Genetics Home Reference: fragile X-associated primary ovarian insufficiency

    Science.gov (United States)

    ... Share: Email Facebook Twitter Home Health Conditions FXPOI Fragile X-associated primary ovarian insufficiency Printable PDF Open All ... Javascript to view the expand/collapse boxes. Description Fragile X-associated primary ovarian insufficiency ( FXPOI ) is a condition ...

  2. Genetics Home Reference: fragile X-associated tremor/ataxia syndrome

    Science.gov (United States)

    ... Share: Email Facebook Twitter Home Health Conditions FXTAS Fragile X-associated tremor/ataxia syndrome Printable PDF Open All ... Javascript to view the expand/collapse boxes. Description Fragile X-associated tremor/ataxia syndrome ( FXTAS ) is characterized by ...

  3. Monogamy inequalities for the Einstein-Podolsky-Rosen paradox and quantum steering

    Science.gov (United States)

    Reid, M. D.

    2013-12-01

    Monogamy inequalities for the way bipartite Einstein-Podolsky-Rosen (EPR) steering can be distributed among N systems are derived. One set of inequalities is based on witnesses with two measurement settings, and may be used to demonstrate correlation of outcomes between two parties, that cannot be shared with more parties. It is shown that the monogamy for steering is directional. Two parties cannot independently demonstrate steering of a third system, using the same two-setting steering witness, but it is possible for one party to steer two independent systems. This result explains the monogamy of two-setting Bell inequality violations and the sensitivity of the continuous variable (CV) EPR criterion to losses on the steering party. We generalize to m settings. A second type of monogamy relation gives the quantitative amount of sharing possible, when the number of parties is less than or equal to m, and takes a form similar to the Coffman-Kundu-Wootters relation for entanglement. The results enable characterization of the tripartite steering for CV Gaussian systems and qubit Greenberger-Horne-Zeilinger and W states.

  4. Boundary Shape Control of the Navier-Stokes Equations and Applications

    Institute of Scientific and Technical Information of China (English)

    Kaitai LI; Jian SU; Aixiang HUANG

    2010-01-01

    In this paper,the geometrical design for the blade's surface(s)in an impeller or for the profile of an aircraft,is modeled from the mathematical point of view by a boundary shape control problem for the Navier-Stokes equations.The objective function is the sum of a global dissipative function and the power of the fluid.The control variables are the geometry of the boundary and the state equations are the Navier-Stokes equations.The Euler-Lagrange equations of the optimal control problem are derived,which are an elliptic boundary value system of fourth order,coupled with the Navier-Stokes equations.The authors also prove the existence of the solution of the optimal control problem,the existence of the solution of the Navier-Stokes equations with mixed boundary conditions,the weak continuity of the solution of the Navier-Stokes equations with respect to the geometry shape of the blade's surface and the existence of solutions of the equations for the G(a)teaux derivative of the solution of the Navier-Stokes equations with respect to the geometry of the boundary.

  5. Die Leben Einsteins eine Reise durch die Geschichte der Physik

    CERN Document Server

    Fiami

    2005-01-01

    Jeder kennt die Namen Einstein, Newton oder Galilei. aber was weiss man über sie? Hier ein Porträt Einsteins anhand von sechs Meilensteinen aus der Geschichte der Physik. Einstein tritt auf als Protagonist in verschiedenen Epochen und bei verschiedenen Entdeckungen, die die Welt verändert haben.

  6. The correlation between fragility, density, and atomic interaction in glass-forming liquids

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lijin; Guan, Pengfei, E-mail: pguan@csrc.ac.cn [Beijing Computational Science Research Center, Beijing 100193 (China); Wang, W. H. [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2016-07-21

    The fragility that controls the temperature-dependent viscous properties of liquids as the glass transition is approached, in various glass-forming liquids with different softness of the repulsive part of atomic interactions at different densities, is investigated by molecular dynamic simulations. We show that the landscape of fragility in purely repulsive systems can be separated into three regions denoted as R{sub I,} R{sub II}, and R{sub III}, respectively, with qualitatively disparate dynamic behaviors: R{sub I} which can be described by “softness makes strong glasses,” R{sub II} where fragility is independent of softness and can only be tuned by density, and R{sub III} with constant fragility, suggesting that density plays an unexpected role for understanding the repulsive softness dependence of fragility. What is more important is that we unify the long-standing inconsistence with respect to the repulsive softness dependence of fragility by observing that a glass former can be tuned more fragile if nonperturbative attraction is added into it. Moreover, we find that the vastly dissimilar influences of attractive interaction on fragility could be estimated from the structural properties of related zero-temperature glasses.

  7. The correlation between fragility, density, and atomic interaction in glass-forming liquids

    International Nuclear Information System (INIS)

    Wang, Lijin; Guan, Pengfei; Wang, W. H.

    2016-01-01

    The fragility that controls the temperature-dependent viscous properties of liquids as the glass transition is approached, in various glass-forming liquids with different softness of the repulsive part of atomic interactions at different densities, is investigated by molecular dynamic simulations. We show that the landscape of fragility in purely repulsive systems can be separated into three regions denoted as R I, R II , and R III , respectively, with qualitatively disparate dynamic behaviors: R I which can be described by “softness makes strong glasses,” R II where fragility is independent of softness and can only be tuned by density, and R III with constant fragility, suggesting that density plays an unexpected role for understanding the repulsive softness dependence of fragility. What is more important is that we unify the long-standing inconsistence with respect to the repulsive softness dependence of fragility by observing that a glass former can be tuned more fragile if nonperturbative attraction is added into it. Moreover, we find that the vastly dissimilar influences of attractive interaction on fragility could be estimated from the structural properties of related zero-temperature glasses.

  8. 3D Topology optimization of Stokes flow problems

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Allan; Dammann, Bernd

    of energy efficient devices for 2D Stokes flow. Creeping flow problems are described by the Stokes equations which model very viscous fluids at macro scales or ordinary fluids at very small scales. The latter gives the motivation for topology optimization problems based on the Stokes equations being a model......The present talk is concerned with the application of topology optimization to creeping flow problems in 3D. This research is driven by the fact that topology optimization has proven very successful as a tool in academic and industrial design problems. Success stories are reported from such diverse...

  9. Derivation of Einstein-Cartan theory from general relativity

    Science.gov (United States)

    Petti, Richard

    2015-04-01

    General relativity cannot describe exchange of classical intrinsic angular momentum and orbital angular momentum. Einstein-Cartan theory fixes this problem in the least invasive way. In the late 20th century, the consensus view was that Einstein-Cartan theory requires inclusion of torsion without adequate justification, it has no empirical support (though it doesn't conflict with any known evidence), it solves no important problem, and it complicates gravitational theory with no compensating benefit. In 1986 the author published a derivation of Einstein-Cartan theory from general relativity, with no additional assumptions or parameters. Starting without torsion, Poincaré symmetry, classical or quantum spin, or spinors, it derives torsion and its relation to spin from a continuum limit of general relativistic solutions. The present work makes the case that this computation, combined with supporting arguments, constitutes a derivation of Einstein-Cartan theory from general relativity, not just a plausibility argument. This paper adds more and simpler explanations, more computational details, correction of a factor of 2, discussion of limitations of the derivation, and discussion of some areas of gravitational research where Einstein-Cartan theory is relevant.

  10. Screening and diagnosis for the fragile X syndrome among the mentally retarded: an epidemiological and psychological survey. Collaborative Fragile X Study Group

    NARCIS (Netherlands)

    B.B.A. de Vries (Bert); B.A. Oostra (Ben); M.F. Niermeijer (Martinus); A. Tibben (Arend); A.M.W. van den Ouweland (Ans); S. Mohkamsing; H.J. Duivenvoorden (Hugo); E. Mol; K. Gelsema; M. van Rijn; D.J.J. Halley (Dicky); L.A. Sandkuijl (Lodewijk)

    1997-01-01

    textabstractThe fragile X syndrome is an X-linked mental retardation disorder caused by an expanded CGG repeat in the first exon of the fragile X mental retardation (FMR1) gene. Its frequency, X-linked inheritance, and consequences for relatives all prompt for

  11. Elastic scattering of a Bose-Einstein condensate at a potential landscape

    International Nuclear Information System (INIS)

    Březinová, Iva; Burgdörfer, Joachim; Lode, Axel U J; Streltsov, Alexej I; Cederbaum, Lorenz S; Alon, Ofir E; Collins, Lee A; Schneider, Barry I

    2014-01-01

    We investigate the elastic scattering of Bose-Einstein condensates at shallow periodic and disorder potentials. We show that the collective scattering of the macroscopic quantum object couples to internal degrees of freedom of the Bose-Einstein condensate such that the Bose-Einstein condensate gets depleted. As a precursor for the excitation of the Bose-Einstein condensate we observe wave chaos within a mean-field theory

  12. Generalized Einstein-Aether theories and the Solar System

    International Nuclear Information System (INIS)

    Bonvin, Camille; Durrer, Ruth; Ferreira, Pedro G.; Zlosnik, Tom G.; Starkman, Glenn

    2008-01-01

    It has been shown that generalized Einstein-Aether theories may lead to significant modifications to the nonrelativistic limit of the Einstein equations. In this paper we study the effect of a general class of such theories on the Solar System. We consider corrections to the gravitational potential in negative and positive powers of distance from the source. Using measurements of the perihelion shift of Mercury and time delay of radar signals to Cassini, we place constraints on these corrections. We find that a subclass of generalized Einstein-Aether theories is compatible with these constraints

  13. Interactions of Ultracold Impurity Particles with Bose-Einstein Condensates

    Science.gov (United States)

    2015-06-23

    AFRL-OSR-VA-TR-2015-0141 INTERACTIONS OF ULTRACOLD IMPURITY PARTICLES WITH BOSE- EINSTEIN CONDENSATES Georg Raithel UNIVERSITY OF MICHIGAN Final...SUBTITLE Interactions of ultracold impurity particles with Bose- Einstein Condensates 5a. CONTRACT NUMBER FA9550-10-1-0453 5b. GRANT NUMBER 5c...Interactions of ultracold impurity particles with Bose- Einstein Condensates Contract/Grant #: FA9550-10-1-0453 Reporting Period: 8/15/2010 to 2/14

  14. [Photoeffects, Einstein's light quanta and the history of their acceptance].

    Science.gov (United States)

    Wiederkehr, Karl Heinrich

    2006-01-01

    It is generally supposed, that the discovery of the efficacy-quantum by Planck was the impetus to Einstein's hypothesis of lightquanta. With its help Einstein could explain the external light-electrical effect. But even years before Einstein had worked at the photoeffect and already made experiments on it. For that reason the article gives a short survey about the history of the lightelectric effects. Lenard's basical work about the release of the photoelectrons is dealt with in detail, without which Einstein would scarcely have found his lightquanta. Furthermore it is shown how difficult it was for the physicists to give up--at least partially--the traditional view of the undulation-nature of light, and how they searched to explain the great energies of the photoelectrons. On the other side it is set forth how Einstein's formula of lightquanta was gradually confirmed. The tragical development of Einstein's personal relations with Johannes Stark and Philipp Lenard are briefly described. Stark was one of the few who supported Einstein's ideas at the beginning. Only with the Compton-effect, which could only be quantitatively interpreted by means of lightquanta and the special theory of relativity 1923, the way was free for the general acceptance of the lightquanta. Einstein did not agree to the obtained dualism of undulation and corpuscle; he had a different solution in mind about the fusion of the two forms of appearance of light.

  15. Approximate radiative solutions of the Einstein equations

    International Nuclear Information System (INIS)

    Kuusk, P.; Unt, V.

    1976-01-01

    In this paper the external field of a bounded source emitting gravitational radiation is considered. A successive approximation method is used to integrate the Einstein equations in Bondi's coordinates (Bondi et al, Proc. R. Soc.; A269:21 (1962)). A method of separation of angular variables is worked out and the approximate Einstein equations are reduced to key equations. The losses of mass, momentum, and angular momentum due to gravitational multipole radiation are found. It is demonstrated that in the case of proper treatment a real mass occurs instead of a mass aspect in a solution of the Einstein equations. In an appendix Bondi's new function is given in terms of sources. (author)

  16. CP violation and modular symmetries

    International Nuclear Information System (INIS)

    Dent, Thomas

    2001-01-01

    We reconsider the origin of CP violation in fundamental theory. Existing string models of spontaneous CP violation make ambiguous predictions, due to the arbitrariness of CP transformation and the apparent noninvariance of the results under duality. We find a modular CP invariance condition, applicable to any predictive model of spontaneous CP violation, which circumvents these problems; it strongly constrains CP violation by heterotic string moduli. The dilaton is also evaluated as a source of CP violation, but is likely experimentally excluded. We consider the prospects for explaining CP violation in strongly coupled strings and brane worlds

  17. Strong plasma shock structures based on the Navier--Stokes equations

    International Nuclear Information System (INIS)

    Abe, K.

    1975-01-01

    The structure of a plasma collisional shock wave is examined on the basis of the Navier--Stokes equations and simultaneously on the basis of the Fokker--Planck equation. The resultant structures are compared to check the validity of the Navier--Stokes equations applied to the structures of strong shock waves. The Navier--Stokes equations give quite correct structures for weak shock waves. For the strong shock waves, the detailed structures obtained from the Navier--Stokes equations differ from the results of the Fokker--Planck equation, but the shock thicknesses of the two shock waves are in relatively close agreement

  18. Spatial entanglement patterns and Einstein-Podolsky-Rosen steering in Bose-Einstein condensates

    Science.gov (United States)

    Fadel, Matteo; Zibold, Tilman; Décamps, Boris; Treutlein, Philipp

    2018-04-01

    Many-particle entanglement is a fundamental concept of quantum physics that still presents conceptual challenges. Although nonclassical states of atomic ensembles were used to enhance measurement precision in quantum metrology, the notion of entanglement in these systems was debated because the correlations among the indistinguishable atoms were witnessed by collective measurements only. Here, we use high-resolution imaging to directly measure the spin correlations between spatially separated parts of a spin-squeezed Bose-Einstein condensate. We observe entanglement that is strong enough for Einstein-Podolsky-Rosen steering: We can predict measurement outcomes for noncommuting observables in one spatial region on the basis of corresponding measurements in another region with an inferred uncertainty product below the Heisenberg uncertainty bound. This method could be exploited for entanglement-enhanced imaging of electromagnetic field distributions and quantum information tasks.

  19. Academic Training: Einstein and beyond: Introduction to General relativity

    CERN Multimedia

    Françoise Benz

    2005-01-01

    2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 3, 4, 5, 6, 7 October from 11:00 to 12:00 - Main Auditorium, bldg. 500 Einstein and beyond: Introduction to General relativity by N. Straumann / Institut fur theoretische physics, Univ. Zürich We review the enduring achievements of Einstein's papers of 1905 and their impact on the further developments in physics. Program : Lectures I and II:Einstein's Contributions to Statistical Mechanics and Quantum Theory Lecture III:Einstein's Thesis at the University of Zürich Lecture IV: From Special to General Relativity Lecture V: The History and the Mystery of the Cosmological Constant ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch

  20. Preserved entropy and fragile magnetism.

    Science.gov (United States)

    Canfield, Paul C; Bud'ko, Sergey L

    2016-08-01

    A large swath of quantum critical and strongly correlated electron systems can be associated with the phenomena of preserved entropy and fragile magnetism. In this overview we present our thoughts and plans for the discovery and development of lanthanide and transition metal based, strongly correlated systems that are revealed by suppressed, fragile magnetism, quantum criticality, or grow out of preserved entropy. We will present and discuss current examples such as YbBiPt, YbAgGe, YbFe2Zn20, PrAg2In, BaFe2As2, CaFe2As2, LaCrSb3 and LaCrGe3 as part of our motivation and to provide illustrative examples.

  1. Einstein was right!

    CERN Multimedia

    2003-01-01

    For the first time scientists have succeeded in measuring the speed of gravity. They took advantage of a rare alignment of Jupiter against a far-off quasar to measure the fundamental constant described by Albert Einstein in his general theory of relativity (2 pages).

  2. CP violation

    Indian Academy of Sciences (India)

    We have just entered a period during which we expect considerable progress toward understanding CP violation. Here we review what we have learnt so far, and what is to be expected in the near future. To do this we cover the foundation of CP violation at a level which can be understood by physicists who are not working ...

  3. Fragility and cooperativity concepts in hydrogen-bonded organic glasses

    International Nuclear Information System (INIS)

    Delpouve, N.; Vuillequez, A.; Saiter, A.; Youssef, B.; Saiter, J.M.

    2012-01-01

    Molecular dynamics at the glass transition of three lactose/oil glassy systems have been investigated according to the cooperativity and fragility approaches. From Donth's approach, the cooperativity length is estimated by modulated temperature calorimetric measurements. Results reveal that modification of the disaccharide by oil leads to increase the disorder degree in the lactose, the size of the cooperative domains and the fragility index. These particular hydrogen-bonded organic glasses follow the general tendency observed on organic and inorganic polymers: the higher the cooperativity length, the higher the value of the fragility index at T g .

  4. New details emerge from the Einstein files

    CERN Multimedia

    Overbye, D

    2002-01-01

    For many years the FBI spied on Einstein. New details of this surveilance are emerging in "The Einstein File: J. Edgar Hoover's Secret War Against the World's Most Famous Scientist," by Fred Jerome, who sued the government with the help of the Public Citizen Litigation Group to obtain a less censored version of the file (1 page).

  5. EPR before EPR: A 1930 Einstein-Bohr thought Experiment Revisited

    Science.gov (United States)

    Nikolic, Hrvoje

    2012-01-01

    In 1930, Einstein argued against the consistency of the time-energy uncertainty relation by discussing a thought experiment involving a measurement of the mass of the box which emitted a photon. Bohr seemingly prevailed over Einstein by arguing that Einstein's own general theory of relativity saves the consistency of quantum mechanics. We revisit…

  6. Finiteness Marking in Boys with Fragile X Syndrome

    Science.gov (United States)

    Sterling, Audra M.; Rice, Mabel L.; Warren, Steven F.

    2012-01-01

    Purpose: The current study investigated finiteness marking (e.g., he walk "s", he walk "ed") in boys with fragile X syndrome (FXS); the boys were grouped based on receptive vocabulary (i.e., borderline, impaired). Method: Twenty-one boys with the full mutation of fragile X, between the ages of 8 and 16 years participated. The…

  7. A Student's Guide to Einstein's Major Papers

    International Nuclear Information System (INIS)

    Janssen, Michel

    2013-01-01

    The core of this volume is formed by four chapters (2–5) with detailed reconstructions of the arguments and derivations in four of Einstein's most important papers, the three main papers of his annus mirabilis 1905 (on the light quantum, Brownian motion, and special relativity) and his first systematic exposition of general relativity of 1916. The derivations are given in sufficient detail and in sufficiently modernized notation (without any serious distortion of the originals) for an undergraduate physics major to read and understand them with far less effort than it would take him or her to understand (English translations of) Einstein's original papers. Each of these four papers is accompanied by a detailed introduction, which covers the conceptual development of the relevant field prior to Einstein's contribution to it and corrects some of the myths surrounding these papers that still have not been fully eradicated among physicists. (One quibble: though Kennedy correctly points out that the goal of the light quantum paper was not to explain the photoelectric effect, it is also not quite right to say that 'it was written to explain the Wien region of blackbody radiation' (p. xv). Einstein used this explanatory feat as the central argument for his light quantum hypothesis.) These four chapters then are the most valuable part of the volume. They could be used, independently of one another, but preferably in conjunction with Einstein's original texts, in courses on quantum mechanics, statistical mechanics, electrodynamics, and general relativity, respectively, to add a historical component to such courses. As a historian of science embedded in a physics department who is regularly called upon to give guest lectures in such courses on the history of their subjects, I can highly recommend the volume for this purpose. However, I would not adopt this volume as (one of) the central text(s) for a course on the history of modern physics. For one thing, chapter 1, which

  8. Dilemmas in counselling females with the fragile X syndrome

    NARCIS (Netherlands)

    B.B.A. de Vries (Bert); H.M. van den Boer-van den Berg; M.F. Niermeijer (Martinus); A. Tibben (Arend)

    1999-01-01

    textabstractThe dilemmas in counselling a mildly retarded female with the fragile X syndrome and her retarded partner are presented. The fragile X syndrome is an X linked mental retardation disorder that affects males and, often less severely, females. Affected females

  9. Seismic fragilities for nuclear power plant risk studies

    International Nuclear Information System (INIS)

    Kennedy, R.P.; Ravindra, M.K.

    1983-01-01

    Seismic fragilities of critical structures and equipment are developed as families of conditional failure frequency curves plotted against peak ground acceleration. The procedure is based on available data combined with judicious extrapolation of design information on plant structures and equipment. Representative values of fragility parameters for typical modern nuclear power plants are provided. Based on the fragility evaluation for about a dozen nuclear power plants, it is proposed that unnecessary conservatism existing in current seismic design practice could be removed by properly accounting for inelastic energy absorption capabilities of structures. The paper discusses the key contributors to seismic risk and the significance of possible correlation between component failures and potential design and construction errors

  10. Effective updating process of seismic fragilities using Bayesian method and information entropy

    International Nuclear Information System (INIS)

    Kato, Masaaki; Takata, Takashi; Yamaguchi, Akira

    2008-01-01

    Seismic probabilistic safety assessment (SPSA) is an effective method for evaluating overall performance of seismic safety of a plant. Seismic fragilities are estimated to quantify the seismically induced accident sequences. It is a great concern that the SPSA results involve uncertainties, a part of which comes from the uncertainty in the seismic fragility of equipment and systems. A straightforward approach to reduce the uncertainty is to perform a seismic qualification test and to reflect the results on the seismic fragility estimate. In this paper, we propose a figure-of-merit to find the most cost-effective condition of the seismic qualification tests about the acceleration level and number of components tested. Then a mathematical method to reflect the test results on the fragility update is developed. A Bayesian method is used for the fragility update procedure. Since a lognormal distribution that is used for the fragility model does not have a Bayes conjugate function, a parameterization method is proposed so that the posterior distribution expresses the characteristics of the fragility. The information entropy is used as the figure-of-merit to express importance of obtained evidence. It is found that the information entropy is strongly associated with the uncertainty of the fragility. (author)

  11. Forests, Fragility and Conflict : Overview and Case Studies

    OpenAIRE

    Harwell, Emily; Farah, Douglas; Blundell, Arthur G.

    2011-01-01

    This book provides a synthesis of key themes and current knowledge about the links among forests, armed conflict, poverty, and various aspects of state fragility. The main themes addressed are: how predatory, incapable, or absent states are fragile in different ways, and their diverse relationships to forests and conflict; the mechanisms by which forests facilitate or prolong conflict, inc...

  12. Data-Driven Decision Making in Fragile Contexts : Evidence from Sudan

    OpenAIRE

    Hamilton, Alexander; Hammer, Craig

    2017-01-01

    Data deficiencies contribute to state fragility and exacerbate fragile states’ already limited capacity to provide basic services, public security and rule of law. The lack of robust, good quality data can also have a disabling effect on government efforts to manage political conflict, and indeed can worsen conflict, since violent settings pose substantial challenges to knowledge generation, capture and application. In short, in fragile contexts the need for reliable evidence at all levels ...

  13. Bayesian methodology for generic seismic fragility evaluation of components in nuclear power plants

    International Nuclear Information System (INIS)

    Yamaguchi, Akira; Campbell, R.D.; Ravindra, M.K.

    1991-01-01

    Bayesian methodology for updating the seismic fragility of components in nuclear power plants is presented. The generic fragility data which have been evaluated based on the past SPSAs are combined with the seismic experience data. Although the seismic experience is limited to the acceleration range below the median capacity of the components, it has been found that the evidence is effective to update the fragility tail. In other words, the uncertainty of the fragility is reduced although the median capacity itself is not modified to a great extent. The annual frequency of failure is also reduced as a result of the updating of the fragility tail. The PDF of the seismic capacity is handled in discrete form, which enables the use of arbitrary type of prior distribution. Accordingly, the Log-N prior can be used which is consistent with the widely used fragility model. For evaluating posterior fragility parameters (A m and B U ), two methods have been proposed. Furthermore, it has been found that the importance of evidence used in the Bayesian methodology can be quantified by the entropy of the evidence. Only the events with high entropy need to be considered in the Bayesian updating of the fragility. The currently available seismic experience database for typical components can be utilized to develop the fragility tail which is contributive to the seismically-induced failure frequency. The combined use of generic fragility and seismic experience data, with the aid of Bayesian methodology, provides refined generic fragility curves which are useful for SPSA studies. (author)

  14. Tip loss correction for actuator / Navier Stokes computations

    DEFF Research Database (Denmark)

    Shen, Wen Zhong; Sørensen, Jens Nørkær; Mikkelsen, Robert Flemming

    2004-01-01

    The new tip loss correction, initially developed for ID BEM computations [1], is now extended to 2D Actuator Disc / Navier-Stokes (AD/NS) computations and 3D Actuator Line / Navier-Stokes (AL/NS) computations. As shown in the paper, the tip loss correction is an important and necessary step...

  15. Conformal and covariant Z4 formulation of the Einstein equations: Strongly hyperbolic first-order reduction and solution with discontinuous Galerkin schemes

    Science.gov (United States)

    Dumbser, Michael; Guercilena, Federico; Köppel, Sven; Rezzolla, Luciano; Zanotti, Olindo

    2018-04-01

    We present a strongly hyperbolic first-order formulation of the Einstein equations based on the conformal and covariant Z4 system (CCZ4) with constraint-violation damping, which we refer to as FO-CCZ4. As CCZ4, this formulation combines the advantages of a conformal and traceless formulation, with the suppression of constraint violations given by the damping terms, but being first order in time and space, it is particularly suited for a discontinuous Galerkin (DG) implementation. The strongly hyperbolic first-order formulation has been obtained by making careful use of first and second-order ordering constraints. A proof of strong hyperbolicity is given for a selected choice of standard gauges via an analytical computation of the entire eigenstructure of the FO-CCZ4 system. The resulting governing partial differential equations system is written in nonconservative form and requires the evolution of 58 unknowns. A key feature of our formulation is that the first-order CCZ4 system decouples into a set of pure ordinary differential equations and a reduced hyperbolic system of partial differential equations that contains only linearly degenerate fields. We implement FO-CCZ4 in a high-order path-conservative arbitrary-high-order-method-using-derivatives (ADER)-DG scheme with adaptive mesh refinement and local time-stepping, supplemented with a third-order ADER-WENO subcell finite-volume limiter in order to deal with singularities arising with black holes. We validate the correctness of the formulation through a series of standard tests in vacuum, performed in one, two and three spatial dimensions, and also present preliminary results on the evolution of binary black-hole systems. To the best of our knowledge, these are the first successful three-dimensional simulations of moving punctures carried out with high-order DG schemes using a first-order formulation of the Einstein equations.

  16. Hermitian-Einstein metrics on holomorphic vector bundles over Hermitian manifolds

    International Nuclear Information System (INIS)

    Xi Zhang

    2004-07-01

    In this paper, we prove the long-time existence of the Hermitian-Einstein flow on a holomorphic vector bundle over a compact Hermitian (non-kaehler) manifold, and solve the Dirichlet problem for the Hermitian-Einstein equations. We also prove the existence of Hermitian-Einstein metrics for holomorphic vector bundles on a class of complete noncompact Hermitian manifolds. (author)

  17. CP violation

    CERN Multimedia

    CERN. Geneva

    1999-01-01

    In the first two lectures, CP violation in the K system is pedagogically reviewed: its manifestations in the neutral K meson systems, in rare K meson decays and in decays of charged K mesons, and results from classical and current experiments, are discussed. In the third lecture, CP Violation in the B system and the forthcoming experimental tests will be discussed.

  18. Is CP violation maximal

    International Nuclear Information System (INIS)

    Gronau, M.

    1984-01-01

    Two ambiguities are noted in the definition of the concept of maximal CP violation. The phase convention ambiguity is overcome by introducing a CP violating phase in the quark mixing matrix U which is invariant under rephasing transformations. The second ambiguity, related to the parametrization of U, is resolved by finding a single empirically viable definition of maximal CP violation when assuming that U does not single out one generation. Considerable improvement in the calculation of nonleptonic weak amplitudes is required to test the conjecture of maximal CP violation. 21 references

  19. The highly fragile glass former Decalin

    International Nuclear Information System (INIS)

    Eibl, Stefan

    2009-01-01

    Systems exhibiting the glass transition can be classified by fragility. In this work we studied structural and dynamical aspects of highly fragile C 10 H 18 Decalin. Trans Decalin is locked into a pseudo-flat centrosymmetric conformation, while cis Decalin interchanges dynamically between chiral, pseudo-spherical ground states. On investigation of the phase behaviour trans Decalin was found to crystallise rapidly and cleanly; its crystal structure could be determined. From the crystal structure the dynamics of crystalline trans Decalin could be calculated using ab-initio lattice energy calculations and compared to measurements. Using neutron diffraction and molecular dynamics simulations the amorphous structure of Decalin was investigated. The difference in structure to the common molecular liquid Cumene is significant. The features of the amorphous structure of sphere-like cis Decalin show strong resemblance to the ones of Argon and metallic glasses. The dynamics of Decalin were investigated in the slightly supercooled liquid range. Using neutron scattering and optical spectroscopy, data was collected for a wide spectral range and several temperatures. The data suggests high fragility for the generic Decalin mixture, which is in agreement with the reported results. By contrast to previous estimations, an extrapolation of our data indicates cis Decalin to be only slightly less fragile than the generic mixture. Finally a lower limit to the four point susceptibility function χ 4 could be calculated and the number of correlated molecules determined. The evolution of this value as a function of T g /T and relaxation time are in agreement with literature. (author) [fr

  20. Einstein's conversion from his static to an expanding universe

    Science.gov (United States)

    Nussbaumer, Harry

    2014-02-01

    In 1917 Einstein initiated modern cosmology by postulating, based on general relativity, a homogenous, static, spatially curved universe. To counteract gravitational contraction he introduced the cosmological constant. In 1922 Alexander Friedman showed that Albert Einstein's fundamental equations also allow dynamical worlds, and in 1927 Georges Lemaître, backed by observational evidence, concluded that our universe was expanding. Einstein impetuously rejected Friedman's as well as Lemaître's findings. However, in 1931 he retracted his former static model in favour of a dynamic solution. This investigation follows Einstein on his hesitating path from a static to the expanding universe. Contrary to an often advocated belief the primary motive for his switch was not observational evidence, but the realisation that his static model was unstable.

  1. Einstein's pathway to the special theory of relativity

    CERN Document Server

    Weinstein, Galina

    2015-01-01

    This book pieces together the jigsaw puzzle of Einstein's journey to discovering the special theory of relativity. Between 1902 and 1905, Einstein sat in the Patent Office and may have made calculations on old pieces of paper that were once patent drafts. One can imagine Einstein trying to hide from his boss, writing notes on small sheets of paper, and, according to reports, seeing to it that the small sheets of paper on which he was writing would vanish into his desk-drawer as soon as he heard footsteps approaching his door. He probably discarded many pieces of papers and calculations and flu

  2. On gravitational wave energy in Einstein gravitational theory

    International Nuclear Information System (INIS)

    Folomeshkin, V.N.; Vlasov, A.A.

    1978-01-01

    By the example of precise wave solutions for the Einstein equations it is shown that a standard commonly adopted formulation of energy-momentum problem with pseudotensors provides us either with a zero or sign-variable values for the energy of gravitational waves. It is shown that if in the Einstein gravitational theory a strict transition to the limits of weak fields is realised then the theory gives us an unambiguous zero result for weak gravitational waves. The well-known non-zero result arises due to incorrect transition to weak field approximation in the Einstein gravitation theory

  3. Restricted gravity: Abelian projection of Einstein's theory

    International Nuclear Information System (INIS)

    Cho, Y.M.

    2013-01-01

    Treating Einstein's theory as a gauge theory of Lorentz group, we decompose the gravitational connection Γμ into the restricted connection made of the potential of the maximal Abelian subgroup H of Lorentz group G and the valence connection made of G/H part of the potential which transforms covariantly under Lorentz gauge transformation. With this we show that Einstein's theory can be decomposed into the restricted gravity made of the restricted connection which has the full Lorentz gauge invariance which has the valence connection as gravitational source. The decomposition shows the existence of a restricted theory of gravitation which has the full general invariance but is much simpler than Einstein's theory. Moreover, it tells that the restricted gravity can be written as an Abelian gauge theory,

  4. New Information about Albert Einstein's Brain.

    Science.gov (United States)

    Falk, Dean

    2009-01-01

    In order to glean information about hominin (or other) brains that no longer exist, details of external neuroanatomy that are reproduced on endocranial casts (endocasts) from fossilized braincases may be described and interpreted. Despite being, of necessity, speculative, such studies can be very informative when conducted in light of the literature on comparative neuroanatomy, paleontology, and functional imaging studies. Albert Einstein's brain no longer exists in an intact state, but there are photographs of it in various views. Applying techniques developed from paleoanthropology, previously unrecognized details of external neuroanatomy are identified on these photographs. This information should be of interest to paleoneurologists, comparative neuroanatomists, historians of science, and cognitive neuroscientists. The new identifications of cortical features should also be archived for future scholars who will have access to additional information from improved functional imaging technology. Meanwhile, to the extent possible, Einstein's cerebral cortex is investigated in light of available data about variation in human sulcal patterns. Although much of his cortical surface was unremarkable, regions in and near Einstein's primary somatosensory and motor cortices were unusual. It is possible that these atypical aspects of Einstein's cerebral cortex were related to the difficulty with which he acquired language, his preference for thinking in sensory impressions including visual images rather than words, and his early training on the violin.

  5. On a theorem of Cattabriga related to Stokes equations

    International Nuclear Information System (INIS)

    Georgescu, V.

    1978-01-01

    We study the ''generalized Stokes boundary value problem'', which is a (generalization of a) linearized version of Navier-Stokes equations and we show the existence and unicity of the weak solution. It is known that these results can be used to prove the existence of weak (local) solutions to the Navier-Stokes equations. However, we are mainly interested in the method of proving it will be seen how easy the result follows from some general theorems about differential forms on a Riemannian manifold. (author)

  6. A Trial of Metformin in Individuals With Fragile X Syndrome

    Science.gov (United States)

    2018-04-10

    Fragile X Syndrome; Fragile X Mental Retardation Syndrome; Mental Retardation, X Linked; Genetic Diseases, X-Linked; Trinucleotide Repeat Expansion; Fra(X) Syndrome; Intellectual Disability; FXS; Neurobehavioral Manifestations; Sex Chromosome Disorders

  7. Fragility and cooperativity concepts in hydrogen-bonded organic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Delpouve, N., E-mail: delpouve.nicolas@gmail.com [AMME-LECAP EA 4528 International Laboratory, University of Rouen, Avenue de l' Universite BP 12, 76801 Saint Etienne du Rouvray (France); Vuillequez, A.; Saiter, A.; Youssef, B.; Saiter, J.M. [AMME-LECAP EA 4528 International Laboratory, University of Rouen, Avenue de l' Universite BP 12, 76801 Saint Etienne du Rouvray (France)

    2012-09-01

    Molecular dynamics at the glass transition of three lactose/oil glassy systems have been investigated according to the cooperativity and fragility approaches. From Donth's approach, the cooperativity length is estimated by modulated temperature calorimetric measurements. Results reveal that modification of the disaccharide by oil leads to increase the disorder degree in the lactose, the size of the cooperative domains and the fragility index. These particular hydrogen-bonded organic glasses follow the general tendency observed on organic and inorganic polymers: the higher the cooperativity length, the higher the value of the fragility index at T{sub g}.

  8. Seismic fragility analysis of structural components for HFBR facilities

    International Nuclear Information System (INIS)

    Park, Y.J.; Hofmayer, C.H.

    1992-01-01

    The paper presents a summary of recently completed seismic fragility analyses of the HFBR facilities. Based on a detailed review of past PRA studies, various refinements were made regarding the strength and ductility evaluation of structural components. Available laboratory test data were analysed to evaluate the formulations used to predict the ultimate strength and deformation capacities of steel, reinforced concrete and masonry structures. The biasness and uncertainties were evaluated within the framework of the fragility evaluation methods widely accepted in the nuclear industry. A few examples of fragility calculations are also included to illustrate the use of the presented formulations

  9. Fermilab | Science | Questions for the Universe | Einstein's Dream of

    Science.gov (United States)

    newsletter Einstein's Dream of Unified Forces In this Section: Einstein's Dream of Unified Forces Are there dream of an ultimate explanation for everything from the tiniest quanta of particle physics to the

  10. Einstein's enigma or black holes in my bubble bath

    CERN Document Server

    Vishveshwara, C V

    2006-01-01

    A funny rendition of the story of gravitation theory from the early historic origins to the developments in astrophysics, focusing on Albert Einstein''s theory of general relativity and black-hole physics.

  11. Radiating Kerr particle in Einstein universe

    International Nuclear Information System (INIS)

    Vaidya, P.C.; Patel, L.K.

    1989-01-01

    A generalized Kerr-NUT type metric is considered in connection with Einstein field equations corresponding to perfect fluid plus a pure radiation field. A general scheme for obtaining the exact solutions of these field equations is developed. Two physically meaningful particular cases are investigated in detail. One gives the field of a radiating Kerr particle embedded in the Einstein universe. The other solution may probably represent a deSitter-like universe pervaded by a pure radiation field. (author). 7 refs

  12. Stationary axisymmetric four dimensional space-time endowed with Einstein metric

    International Nuclear Information System (INIS)

    Hasanuddin; Azwar, A.; Gunara, B. E.

    2015-01-01

    In this paper, we construct Ernst equation from vacuum Einstein field equation for both zero and non-zero cosmological constant. In particular, we consider the case where the space-time admits axisymmetric using Boyer-Lindquist coordinates. This is called Kerr-Einstein solution describing a spinning black hole. Finally, we give a short discussion about the dynamics of photons on Kerr-Einstein space-time

  13. On Einstein's kinematics and his derivation of Lorentz transformation equations

    International Nuclear Information System (INIS)

    Gulati, Shobha; Gulati, S.P.

    1981-01-01

    Recently the present authors have claimed that Einstein's historic derivation of 1905 of Lorentz transformation equations is a 'howler' - a correct result achieved through some incorrect steps. In the present contribution, this howler is fully resolved. Incidently, Einstein's kinematical considerations are found to be void of any new definitional elements or conventionality as unjustifiably claimed by Einstein and some other scientists. (author)

  14. CP violation

    International Nuclear Information System (INIS)

    Quinn, H.

    1995-12-01

    In this talk the author briefly reviews the cosmological importance of CP violation and the status of calculations of baryogenisis in the context of the Standard Model. The author then turns to a discussion of Standard Model Predictions for CP violation in B decays, stressing the importance of multiple measurements to overconstrain the model parameters and thus search for indications of beyond-Standard-Model physics

  15. The Classical Version of Stokes' Theorem Revisited

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    2005-01-01

    Using only fairly simple and elementary considerations - essentially from first year undergraduate mathematics - we prove that the classical Stokes' theorem for any given surface and vector field in $\\mathbb{R}^{3}$ follows from an application of Gauss' divergence theorem to a suitable modification...... of the vector field in a tubular shell around the given surface. The intuitive appeal of the divergence theorem is thus applied to bootstrap a corresponding intuition for Stokes' theorem. The two stated classical theorems are (like the fundamental theorem of calculus) nothing but shadows of the general version...... to above. Our proof that Stokes' theorem follows from Gauss' divergence theorem goes via a well known and often used exercise, which simply relates the concepts of divergence and curl on the local differential level. The rest of the paper uses only integration in $1$, $2$, and $3$ variables together...

  16. Reassessing the Ritz-Einstein debate on the radiation asymmetry in classical electrodynamics

    Science.gov (United States)

    Frisch, Mathias; Pietsch, Wolfgang

    2016-08-01

    We investigate the debate between Walter Ritz and Albert Einstein on the origin and nature of the radiation asymmetry. We argue that Ritz's views on the radiation asymmetry were far richer and nuanced than the oft-cited joint letter with Einstein (Ritz & Einstein, 1909) suggests, and that Einstein's views in 1909 on the asymmetry are far more ambiguous than is commonly recognized. Indeed, there is strong evidence that Einstein ultimately came to agree with Ritz that elementary radiation processes in classical electrodynamics are non-symmetric and fully retarded.

  17. Errors and violations

    International Nuclear Information System (INIS)

    Reason, J.

    1988-01-01

    This paper is in three parts. The first part summarizes the human failures responsible for the Chernobyl disaster and argues that, in considering the human contribution to power plant emergencies, it is necessary to distinguish between: errors and violations; and active and latent failures. The second part presents empirical evidence, drawn from driver behavior, which suggest that errors and violations have different psychological origins. The concluding part outlines a resident pathogen view of accident causation, and seeks to identify the various system pathways along which errors and violations may be propagated

  18. Einstein, Bohr, and Bell

    Science.gov (United States)

    Bellac, Michel Le

    2014-11-01

    The final form of quantum physics, in the particular case of wave mechanics, was established in the years 1925-1927 by Heisenberg, Schrödinger, Born and others, but the synthesis was the work of Bohr who gave an epistemological interpretation of all the technicalities built up over those years; this interpretation will be examined briefly in Chapter 10. Although Einstein acknowledged the success of quantum mechanics in atomic, molecular and solid state physics, he disagreed deeply with Bohr's interpretation. For many years, he tried to find flaws in the formulation of quantum theory as it had been more or less accepted by a large majority of physicists, but his objections were brushed away by Bohr. However, in an article published in 1935 with Podolsky and Rosen, universally known under the acronym EPR, Einstein thought he had identified a difficulty in the by then standard interpretation. Bohr's obscure, and in part beyond the point, answer showed that Einstein had hit a sensitive target. Nevertheless, until 1964, the so-called Bohr-Einstein debate stayed uniquely on a philosophical level, and it was actually forgotten by most physicists, as the few of them aware of it thought it had no practical implication. In 1964, the Northern Irish physicist John Bell realized that the assumptions contained in the EPR article could be tested experimentally. These assumptions led to inequalities, the Bell inequalities, which were in contradiction with quantum mechanical predictions: as we shall see later on, it is extremely likely that the assumptions of the EPR article are not consistent with experiment, which, on the contrary, vindicates the predictions of quantum physics. In Section 3.2, the origin of Bell's inequalities will be explained with an intuitive example, then they will be compared with the predictions of quantum theory in Section 3.3, and finally their experimental status will be reviewed in Section 3.4. The debate between Bohr and Einstein goes much beyond a

  19. Einstein's Gravity and Dark Energy/Matter

    CERN Document Server

    Sarfatti, J

    2003-01-01

    Should Einstein's general relativity be quantized in the usual way even though it is not renormalizable the way the spin 1/2 lepto-quark - spin 1 gauge force boson local field theories are? Condensed matter theorists using P.W. Anderson's "More is different" approach, consistent with Andrei Sakharov's idea of "metric elasticity" with gravity emergent out of quantum electrodynamic zero point vacuum fluctuations, is the approach I take in this paper. The QED vacuum in globally-flat Minkowski space-time is unstable due to exchange of virtual photons between virtual electrons and positron "holes" near the -mc2 Fermi surface well inside the 2mc2 energy gap. This results in a non-perturbative emergence of both Einstein's gravity and a unified dark energy/dark matter w = -1 exotic vacuum zero point fluctuation field controlled by the local macro-quantum vacuum coherent field. The latter is a Bose-Einstein condensate of virtual off-mass-shell bound electron-positron pairs. The dark matter exotic vacuum phase with pos...

  20. Discrete Bose-Einstein spectra

    International Nuclear Information System (INIS)

    Vlad, Valentin I.; Ionescu-Pallas, Nicholas

    2001-03-01

    The Bose-Einstein energy spectrum of a quantum gas, confined in a rigid cubic box, is shown to become discrete and strongly dependent on the box geometry (size L), temperature, T and atomic mass number, A at , in the region of small γ=A at TV 1/3 . This behavior is the consequence of the random state degeneracy in the box. Furthermore, we demonstrate that the total energy does not obey the conventional law any longer, but a new law, which depends on γ and on the quantum gas fugacity. This energy law imposes a faster decrease to zero than it is classically expected, for γ→0. The lighter the gas atoms, the higher the temperatures or the box size, for the same effects in the discrete Bose-Einstein regime. (author)

  1. Synthesis and inversion of Stokes spectral profiles. Thesis

    International Nuclear Information System (INIS)

    Murphy, G.A.

    1990-01-01

    Observations of Stokes spectral profiles enable the magnetic fields on the Sun's surface to be determined. Inversion is the process whereby the profiles are reduced to magnetic field vectors. One of the most robust, accurate and rapid methods available for inversion uses the least-squares fitting of analytical Stokes profiles. As this technique is suitable for the automated reduction of large sets of data, it has been adopted for use with the Advanced Stokes Polarimeter, presently under development. The limitations of inversion by analytical profile fitting have not been firmly established. Confident analysis of magnet field vectors depends upon the precise interpretation of reduced data. In this work, a framework is introduced which allows such an assessment to be made. The magnetofluid-static sunspot models presented here provide a self-consistent range of physical conditions similar to those in sunspots. Inversion can then be carried out on Stokes profiles synthesized from these known realistic conditions. The capabilities of an inversion technique can be evaluated by comparison between the models and the deduced values

  2. Solutions of Navier-Stokes Equation with Coriolis Force

    Directory of Open Access Journals (Sweden)

    Sunggeun Lee

    2017-01-01

    Full Text Available We investigate the Navier-Stokes equation in the presence of Coriolis force in this article. First, the vortex equation with the Coriolis effect is discussed. It turns out that the vorticity can be generated due to a rotation coming from the Coriolis effect, Ω. In both steady state and two-dimensional flow, the vorticity vector ω gets shifted by the amount of -2Ω. Second, we consider the specific expression of the velocity vector of the Navier-Stokes equation in two dimensions. For the two-dimensional potential flow v→=∇→ϕ, the equation satisfied by ϕ is independent of Ω. The remaining Navier-Stokes equation reduces to the nonlinear partial differential equations with respect to the velocity and the corresponding exact solution is obtained. Finally, the steady convective diffusion equation is considered for the concentration c and can be solved with the help of Navier-Stokes equation for two-dimensional potential flow. The convective diffusion equation can be solved in three dimensions with a simple choice of c.

  3. Incompressible Navier-Stokes equations. Theory and practice

    Energy Technology Data Exchange (ETDEWEB)

    Gjesdal, T.

    1996-12-31

    This paper contains notes from a seminar presented at the Dept. of Mathematics in the University of Bergen, Norway, Oct. 1996. It first introduces the theory of existence and uniqueness of solutions to the incompressible Navier-Stokes equation and defines a well-posed initial-boundary value problem. It then discusses different methods for solving numerically the Navier-Stokes equations in velocity-pressure formulation. The emphasis is on pressure correction methods. 19 refs.

  4. Abnormal anti-Stokes Raman emission as a coherent anti-Stokes Raman scattering-like process in disordered media

    International Nuclear Information System (INIS)

    Baltog, Ioan; Baibarac, Mihaela; Smaranda, Ion; Lefrant, Serge

    2011-01-01

    In this paper, we demonstrate that, by continuous single beam excitation, one can generate an abnormal anti-Stokes Raman emission (AASRE) whose properties are similar to a coherent anti-Stokes Raman scattering (CARS). The effect has been observed in materials which possess intrinsically nonlinear properties (LiNbO 3 and CdS), which have the electric susceptibility of third order different from zero, χ (3) ≠ 0, as well as in materials that become nonlinear under resonant optical excitation. In the latter case, we used poly-3,4-ethylendioxythiophene (PEDOT) in its undoped state deposited electrochemically on Au support. Raman studies corroborated with images of optical microscopy demonstrate that the production of AASRE is conditioned by the existence of a particular morphology of the sample able to ensure efficient transport of the light inside the sample through a multiple light scattering mechanism. In this context, it was found that LiNbO 3 and CdS in powder form as well as the PEDOT films layered on a rough Au substrate are suitable morphological forms. We explain AASRE as resulting from a wave-mixing mechanism of the incident laser light ω l with a Stokes-shifted Raman light ω S produced by a spontaneous Raman light scattering process, both strongly scattered inside the sample. As a CARS process, AASRE is conditioned by the achievement of phase-matching requirements, which makes the difference between the wave vectors of mixing light close to zero, Δk =/2k l - k S - k CARS /∼ 0. In condensed media, the small dispersion of the refractive index makes Δk ∼ 0 so that the formation of a favourable phase-matching geometry may be accomplished even at a crossing angle θ of travelling scattered light ω l and ω S . For tightly focused beams, the requirement of phase matching relaxes; it is no longer sensitive to the Raman shift, so that a wide intense anti-Stokes Raman spectrum is observed at an angle larger than the Stokes Raman spectrum.

  5. CP violation

    International Nuclear Information System (INIS)

    Gronau, M.

    1995-01-01

    We review the present status of the Standard Model of CP violation, which is based on a complex phase in the Cabibbo-Kobayashi-Maskawa (CKM) matrix. So far CP violation has been observed only in K 0 -K 0 mixing, consistent with a sizable phase. The implications of future CP nonconserving measusrements in K and B decays are discussed within the model. Direct CP violation in K→2π may be observed in the near future, however this would not be a powerful test of the model. B decays provide a wide variety of CP asymmetry measurements, which can serve as precise tests of the Standard Model in cases where the asymmetry is cleanly related to phases of CKM matrix elements. Some of the most promising cases are discussed. ((orig.))

  6. Albert Einstein

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    In a single year, 1905, Albert Einstein made several dramatic contributions to physics. He deduced the true nature of Brownian motion (doing much to underline the molecular and atomic nature of matter), he demonstrated the particle nature of light in a way which was accessible to experimental investigation (the work for which he received the Nobel prize) and, most dramatically of all, he conceived the special theory of relativity

  7. R-parity violating supersymmetry

    CERN Document Server

    Barbier, R.; Besancon, M.; Chemtob, M.; Deandrea, A.; Dudas, E.; Fayet, Pierre; Lavignac, S.; Moreau, G.; Perez, E.; Sirois, Y.

    2004-01-01

    The possible appearance of R-parity violating couplings, and hence implicitly the question of lepton and baryon number conservation, has been emphasised since the early development of supersymmetric theories. The rich phenomenology implied by R-parity violation has now gained full attention in the search for supersymmetry. In this review, theoretical and phenomenological implications of R-parity violation in supersymmetric theories are discussed, in relation with particle and astroparticle physics. Fundamental aspects include the relation with continuous and discrete symmetries, up to more recent developments on the Abelian family symmetries and hierarchy of R-parity violating couplings. The question of the generation of the standard model neutrino masses and mixings is presented. The possible contributions of R-parity violating Yukawa couplings in processes involving virtual supersymmetric particles and the resulting constraints are reviewed. Finally, a survey of the direct production of supersymmetric parti...

  8. Agricultural Fragility Estimates Subjected to Volcanic Ash Fall Hazards

    Science.gov (United States)

    Ham, H. J.; Lee, S.; Choi, S. H.; Yun, W. S.

    2015-12-01

    Agricultural Fragility Estimates Subjected to Volcanic Ash Fall Hazards Hee Jung Ham1, Seung-Hun Choi1, Woo-Seok Yun1, Sungsu Lee2 1Department of Architectural Engineering, Kangwon National University, Korea 2Division of Civil Engineering, Chungbuk National University, Korea ABSTRACT In this study, fragility functions are developed to estimate expected volcanic ash damages of the agricultural sector in Korea. The fragility functions are derived from two approaches: 1) empirical approach based on field observations of impacts to agriculture from the 2006 eruption of Merapi volcano in Indonesia and 2) the FOSM (first-order second-moment) analytical approach based on distribution and thickness of volcanic ash observed from the 1980 eruption of Mt. Saint Helens and agricultural facility specifications in Korea. Fragility function to each agricultural commodity class is presented by a cumulative distribution function of the generalized extreme value distribution. Different functions are developed to estimate production losses from outdoor and greenhouse farming. Seasonal climate influences vulnerability of each agricultural crop and is found to be a crucial component in determining fragility of agricultural commodities to an ash fall. In the study, the seasonality coefficient is established as a multiplier of fragility function to consider the seasonal vulnerability. Yields of the different agricultural commodities are obtained from Korean Statistical Information Service to create a baseline for future agricultural volcanic loss estimation. Numerically simulated examples of scenario ash fall events at Mt. Baekdu volcano are utilized to illustrate the application of the developed fragility functions. Acknowledgements This research was supported by a grant 'Development of Advanced Volcanic Disaster Response System considering Potential Volcanic Risk around Korea' [MPSS-NH-2015-81] from the Natural Hazard Mitigation Research Group, Ministry of Public Safety and Security of

  9. The Einstein@Home search for gravitational waves and neutron stars

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Einstein@Home is a volunteer distributed computing project with more than 300,000 participants. Like other volunteer computing projects, Einstein@Home harvests idle computer cycles from the the laptop and desktop computers of the general public. This provides enormous computing power, on the scale of some of the world's fastest supercomputers, but at very low cost. I describe the current status of the Einstein@Home search for new neutron stars, using data from the Laser Interferometer Gravitational-wave Observatory (LIGO), from the Arecibo and Parkes radio telescopes, and from the Fermi gamma-ray satellite. The sensitivity of these searches is limited by computing power, so the Einstein@Home approach allows the detection of weaker signals than more conventional approaches. In the past 18 months, Einstein@Home has discovered more than 20 new radio and gamma-ray pulsars, including a number of particularly interesting and exotic systems.

  10. Moral Violations Reduce Oral Consumption

    Science.gov (United States)

    Chan, Cindy; Van Boven, Leaf; Andrade, Eduardo B.; Ariely, Dan

    2014-01-01

    Consumers frequently encounter moral violations in everyday life. They watch movies and television shows about crime and deception, hear news reports of corporate fraud and tax evasion, and hear gossip about cheaters and thieves. How does exposure to moral violations influence consumption? Because moral violations arouse disgust and because disgust is an evolutionarily important signal of contamination that should provoke a multi-modal response, we hypothesize that moral violations affect a key behavioral response to disgust: reduced oral consumption. In three experiments, compared with those in control conditions, people drank less water and chocolate milk while (a) watching a film portraying the moral violations of incest, (b) writing about moral violations of cheating or theft, and (c) listening to a report about fraud and manipulation. These findings imply that “moral disgust” influences consumption in ways similar to core disgust, and thus provide evidence for the associations between moral violations, emotions, and consumer behavior. PMID:25125931

  11. Moral Violations Reduce Oral Consumption.

    Science.gov (United States)

    Chan, Cindy; Van Boven, Leaf; Andrade, Eduardo B; Ariely, Dan

    2014-07-01

    Consumers frequently encounter moral violations in everyday life. They watch movies and television shows about crime and deception, hear news reports of corporate fraud and tax evasion, and hear gossip about cheaters and thieves. How does exposure to moral violations influence consumption? Because moral violations arouse disgust and because disgust is an evolutionarily important signal of contamination that should provoke a multi-modal response, we hypothesize that moral violations affect a key behavioral response to disgust: reduced oral consumption. In three experiments, compared with those in control conditions, people drank less water and chocolate milk while (a) watching a film portraying the moral violations of incest, (b) writing about moral violations of cheating or theft, and (c) listening to a report about fraud and manipulation. These findings imply that "moral disgust" influences consumption in ways similar to core disgust, and thus provide evidence for the associations between moral violations, emotions, and consumer behavior.

  12. The Seismic Fragility Evaluation of an Offsite Transformer according to Aging Effects

    International Nuclear Information System (INIS)

    Kim, Min Kyu; Choi, In Kil

    2008-01-01

    A seismic fragility analysis was performed, especially for an aged electric power transmission system, in this study. A real electric transformer system for Korean Nuclear Power Plants was selected for the seismic fragility evaluation. In the case of a seismic fragility analysis we should use design material properties and conditions. However material properties and environmental conditions of most structures and equipment are changed according to a lapse of time. Aging conditions greatly affect the integrity of the structures and equipment at NPP sites, but it is very difficult to estimate them qualitatively. Integrity of an anchor bolt system was considered with the aging conditions for an electric transformer system. At first, a seismic fragility analysis was performed for a fine condition for an electric transformer system. After that, a seismic fragility analysis according to the fastener of an anchor bolt system was conducted. This study showed that a looser anchor bolt creates seismic responses and seismic fragility changes of more 10%

  13. Beyond Einstein: Exploring the Extreme Universe

    Science.gov (United States)

    Barbier, Louis M.

    2005-01-01

    This paper will give an overview of the NASA Universe Division Beyond Einstein program. The Beyond Einstein program consists of a series of exploratory missions to investigate some of the most important and pressing problems in modern-day astrophysics - including searches for Dark Energy and studies of the earliest times in the universe, during the inflationary period after the Big Bang. A variety of new technologies are being developed both in the science instrumentation these missions will carry and in the spacecraft that will carry those instruments.

  14. Partially massless graviton on beyond Einstein spacetimes

    Science.gov (United States)

    Bernard, Laura; Deffayet, Cédric; Hinterbichler, Kurt; von Strauss, Mikael

    2017-06-01

    We show that a partially massless graviton can propagate on a large set of spacetimes which are not Einstein spacetimes. Starting from a recently constructed theory for a massive graviton that propagates the correct number of degrees of freedom on an arbitrary spacetime, we first give the full explicit form of the scalar constraint responsible for the absence of a sixth degree of freedom. We then spell out generic conditions for the constraint to be identically satisfied, so that there is a scalar gauge symmetry which makes the graviton partially massless. These simplify if one assumes that spacetime is Ricci symmetric. Under this assumption, we find explicit non-Einstein spacetimes (some, but not all, with vanishing Bach tensors) allowing for the propagation of a partially massless graviton. These include in particular the Einstein static Universe.

  15. Statistics of the Navier–Stokes-alpha-beta regularization model for fluid turbulence

    International Nuclear Information System (INIS)

    Hinz, Denis F; Kim, Tae-Yeon; Fried, Eliot

    2014-01-01

    We explore one-point and two-point statistics of the Navier–Stokes-αβ regularization model at moderate Reynolds number (Re ≈ 200) in homogeneous isotropic turbulence. The results are compared to the limit cases of the Navier–Stokes-α model and the Navier–Stokes-αβ model without subgrid-scale stress, as well as with high-resolution direct numerical simulation. After reviewing spectra of different energy norms of the Navier–Stokes-αβ model, the Navier–Stokes-α model, and Navier–Stokes-αβ model without subgrid-scale stress, we present probability density functions and normalized probability density functions of the filtered and unfiltered velocity increments along with longitudinal velocity structure functions of the regularization models and direct numerical simulation results. We highlight differences in the statistical properties of the unfiltered and filtered velocity fields entering the governing equations of the Navier–Stokes-α and Navier–Stokes-αβ models and discuss the usability of both velocity fields for realistic flow predictions. The influence of the modified viscous term in the Navier–Stokes-αβ model is studied through comparison to the case where the underlying subgrid-scale stress tensor is neglected. Whereas, the filtered velocity field is found to have physically more viable probability density functions and structure functions for the approximation of direct numerical simulation results, the unfiltered velocity field is found to have flatness factors close to direct numerical simulation results. (paper)

  16. The formative years of relativity the history and meaning of Einstein's Princeton lectures : featuring Einstein's classic text The meaning of relativity in its historical context

    CERN Document Server

    Gutfreund, Hanoch

    2017-01-01

    First published in 1922 and based on lectures delivered in May 1921, Albert Einstein's The Meaning of Relativity offered an overview and explanation of the then new and controversial theory of relativity. The work would go on to become a monumental classic, printed in numerous editions and translations worldwide. Now, The Formative Years of Relativity introduces Einstein's masterpiece to new audiences. This beautiful volume contains Einstein's insightful text, accompanied by important historical materials and commentary looking at the origins and development of general relativity. Hanoch Gutfreund and Jurgen Renn provide fresh, original perspectives, placing Einstein's achievements into a broader context for all readers. In this book, Gutfreund and Renn tell the rich story behind the early reception, spread, and consequences of Einstein's ideas during the formative years of general relativity in the late 1910s and 1920s. They show that relativity's meaning changed radically throughout the nascent years of it...

  17. The incompressible non-relativistic Navier-Stokes equation from gravity

    International Nuclear Information System (INIS)

    Bhattacharyya, Sayantani; Minwalla, Shiraz; Wadia, Spenta R.

    2009-01-01

    We note that the equations of relativistic hydrodynamics reduce to the incompressible Navier-Stokes equations in a particular scaling limit. In this limit boundary metric fluctuations of the underlying relativistic system turn into a forcing function identical to the action of a background electromagnetic field on the effectively charged fluid. We demonstrate that special conformal symmetries of the parent relativistic theory descend to 'accelerated boost' symmetries of the Navier-Stokes equations, uncovering a conformal symmetry structure of these equations. Applying our scaling limit to holographically induced fluid dynamics, we find gravity dual descriptions of an arbitrary solution of the forced non-relativistic incompressible Navier-Stokes equations. In the holographic context we also find a simple forced steady state shear solution to the Navier-Stokes equations, and demonstrate that this solution turns unstable at high enough Reynolds numbers, indicating a possible eventual transition to turbulence.

  18. Wavefront sensing with all-digital Stokes measurements

    CSIR Research Space (South Africa)

    Dudley, Angela L

    2014-09-25

    Full Text Available to wavefront sensing [8] based on Stokes polarimetry which makes use of the amplitude and phase relationship between orthogonal states of polarization. With our approach a field of interest is generated by encoding an appropriate hologram on a spatial light... modulator (SLM). Since SLMs are diffraction-inefficient, we can exploit the amplitude relationship between the orthogonal polarization states allowing the execution of Stokes polarimetry of the co-linear superposition of the reference beam and the beam...

  19. Structure of the space of solutions of Einstein's equations II: Several killing fields and the Einstein-Yang-Mills equations

    Energy Technology Data Exchange (ETDEWEB)

    Arms, J.M.; Marsden, J.E.; Moncrief, V.

    1982-11-01

    The space of solutions of Einstein's vacuum equations is shown to have conical singularities at each spacetime possessing a compact Cauchy surface of constant mean curvature and a nontrivial set of Killing fields. Similar results are shown for the coupled Einstein-Yang-Mills system. Combined with an appropriate slice theorem, the results show that the space of geometrically equivalent solutions is a stratified manifold with each stratum being a symplectic manifold characterized by the symmetry type of its members. Contents: Introduction 1. The Kuranishi map and its properties. 2. The momentum constraints. 3. The Hamiltonian constraints. 4. The Einstein-Yang-Mills system. 5. Discussion and examples.

  20. Diagnostic, carrier and prenatal genetic testing for fragile X ...

    African Journals Online (AJOL)

    Background. Fragile X syndrome (FXS), the most common inherited cause of intellectual disability (ID) worldwide, is caused by the expansion of a CGG repeat in the fragile X mental retardation gene (FMR-1) gene. Objectives. To review, retrospectively, the genetic services for FXS and other FMR-1-related disorders ...

  1. Whole-of-Government Approaches to Fragile States in Africa

    DEFF Research Database (Denmark)

    Olsen, Gorm Rye

    2013-01-01

    For a number of years fragile states have been high on the foreign policy agendas of the USA and the EU. Both actors look upon fragile states with great concern and consider them as security threats. Officially they give priority to ‘whole-of-government approaches’ (wga) when addressing the threats...

  2. Cities could hold the key to understanding fragility | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Cities are engines of economic growth and the primary sites of basic service delivery. Yet weak governance, along with inequalities related to income, social class, religion, and gender, may lead to a breakdown of systems and structures, and eventually to "fragile cities." Although the fragile cities concept is relatively new, ...

  3. On the stability of the Einstein universe

    International Nuclear Information System (INIS)

    Soares, I.D.

    1983-01-01

    It is shown sthat the Einstein Universe is stable by a large class of exact perturbations, which are made starting from a detailed exam of the topology of the model, and which include perturbations of the type considered by Lemaitre. The problem is reduced to the one-dimensional motion of a particle, in a potential well whose minimum corresponds to the configuration of the Einstein Universe. (Author) [pt

  4. EMQN best practice guidelines for the molecular genetic testing and reporting of fragile X syndrome and other fragile X-associated disorders

    Science.gov (United States)

    Biancalana, Valérie; Glaeser, Dieter; McQuaid, Shirley; Steinbach, Peter

    2015-01-01

    Different mutations occurring in the unstable CGG repeat in 5' untranslated region of FMR1 gene are responsible for three fragile X-associated disorders. An expansion of over ∼200 CGG repeats when associated with abnormal methylation and inactivation of the promoter is the mutation termed ‘full mutation' and is responsible for fragile X syndrome (FXS), a neurodevelopmental disorder described as the most common cause of inherited intellectual impairment. The term ‘abnormal methylation' is used here to distinguish the DNA methylation induced by the expanded repeat from the ‘normal methylation' occurring on the inactive X chromosomes in females with normal, premutation, and full mutation alleles. All male and roughly half of the female full mutation carriers have FXS. Another anomaly termed ‘premutation' is characterized by the presence of 55 to ∼200 CGGs without abnormal methylation, and is the cause of two other diseases with incomplete penetrance. One is fragile X-associated primary ovarian insufficiency (FXPOI), which is characterized by a large spectrum of ovarian dysfunction phenotypes and possible early menopause as the end stage. The other is fragile X-associated tremor/ataxia syndrome (FXTAS), which is a late onset neurodegenerative disorder affecting males and females. Because of the particular pattern and transmission of the CGG repeat, appropriate molecular testing and reporting is very important for the optimal genetic counselling in the three fragile X-associated disorders. Here, we describe best practice guidelines for genetic analysis and reporting in FXS, FXPOI, and FXTAS, including carrier and prenatal testing. PMID:25227148

  5. The second postulate of Einstein's theory of special relativity

    International Nuclear Information System (INIS)

    McMorris, M.N.

    1979-01-01

    This paper argues that Einstein in his original publication on special relativity uses two separate principles concerning the velocity of light: (i) its value, c(s), is independent of the motion of its source; (ii) its value, c(o), is independent of the motion of the observer. Where commentators have not been plainly ignorant of the existence of both principles in Einstein's work, they have been uncertain as to which one should be put forward. Uncertainty has arisen in the literature because Einstein occassionally uses constant velocity of light without any qualification. This paper sets out specifically to clear up the uncertainty as to whether c(s) or c(o) is being referred to in the early sections. It is established that c(s) is used right up to the middle of the third section, when c(o) is introduced for the first time. The paper also emphasises that there was no need to introduce c(o) before this point. It clarifies another (neglected) point also, that in so far as Einstein uses c(s), this constancy of the wave propagation is not peculiar to light; but in so far as he uses c(o) it is. The occassion is also taken to point out a contradiction and a logical infelicity occurring in Einstein's paper. The intention here is to show that Einstein's original oaper, at least up to the derivation of the Lorentz transformation equations, was not as satisfactory as it could have been. (auth.)

  6. Herwig Schopper Einstein's Legacy

    CERN Multimedia

    Schneegans, Susan

    2005-01-01

    "Last June, the United Nations declared 2005 the International Year of Physics and invited UNESCO to take the lead in celebrating the hundreth anniversary of Albert Einstein's legandary articles on relativisty, quantum theory and Brownian motion" (3 pages)

  7. Resonances for coupled Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Haroutyunyan, H.L.; Nienhuis, G.

    2004-01-01

    The properties of a Bose-Einstein condensate in a two-well potential can be manipulated by periodic modulation of the potential parameters. We study the effects arising from modulating the barrier height and the difference in well depth. At certain modulation frequencies the system exhibits resonances, which may show up in an enhancement of the tunneling rate between the wells. Resonances can be used to control the particle distribution over the wells. Some of the effects occurring in the two-well system also arise for a Bose-Einstein condensate in an optical lattice

  8. Einstein and general relativity: historical perspectives

    International Nuclear Information System (INIS)

    Chandrasekhar, S.

    1978-01-01

    The place of Einstein in 20th-century physics is discussed. The basic ideas that led Einstein to his theory of gravitation by the sheer power of speculative thought are described in the most general terms. The prediction of the bending of starlight by the Sun and the eclipse expedition of 1919 are recounted. The author feels that ''the general theory of relativity is incredibly rich in its content;...one finds a glittering face at almost every turn.'' The prediction of black holes by general relativity is noted

  9. Mathematical implications of Einstein-Weyl causality

    International Nuclear Information System (INIS)

    Borchers, H.J.; Sen, R.N.

    2006-01-01

    The present work is the first systematic attempt at answering the following fundamental question: what mathematical structures does Einstein-Weyl causality impose on a point-set that has no other previous structure defined on it? The authors propose an axiomatization of Einstein-Weyl causality (inspired by physics), and investigate the topological and uniform structures that it implies. Their final result is that a causal space is densely embedded in one that is locally a differentiable manifold. The mathematical level required of the reader is that of the graduate student in mathematical physics. (orig.)

  10. Bohr vs. Einstein: Fortolkning af kvantemekanikken

    DEFF Research Database (Denmark)

    Andersen, Christian Kraglund; Wade, Andrew Christopher James

    2013-01-01

    Siden 1913, da Bohr fremlagde sin kvantemekaniske model for atomet, har fysikere diskuteret, hvordan kvan- temekanikken skal fortolkes. Specielt aktive i denne diskussion var Bohr og Einstein, som havde modstridende opfattelser af, hvordan kvantemekanikken skulle forstås. Kan katte være både...... levende og døde på samme tid? Kan vi teleportere partikler mellem Månen og Jorden? Disse spørgsmål, og mange flere, forsøgte Bohr og Einstein at besvare, og det vil vi ligeledes i denne artikel....

  11. The problem of electric sources in Einstein's Hermite-symmetric field theory

    International Nuclear Information System (INIS)

    Kreisel, E.

    1986-01-01

    The possibility is investigated to introduce a geometric source without A-invariance and Hermite-symmetry breaking of Einstein's Hermitian relativity. It would be very meaningful to interpret a source of this kind as electric current. With this extension Einstein's unitary field theory contains Einstein's gravitation, electromagnetism and the gluonic vacuum of chromodynamics. (author)

  12. A note on Einstein-Sasaki metrics in D ≥ 7

    International Nuclear Information System (INIS)

    Chen, W; Lue, H; Pope, C N; Vazquez-Poritz, J F

    2005-01-01

    In this paper, we obtain new non-singular Einstein-Sasaki spaces in dimensions D ≥ 7. The local construction involves taking a circle bundle over a (D - 1)-dimensional Einstein-Kaehler metric that is itself constructed as a complex line bundle over a product of Einstein-Kaehler spaces. In general, the resulting Einstein-Sasaki spaces are singular, but if parameters in the local solutions satisfy appropriate rationality conditions, the metrics extend smoothly onto complete and non-singular compact manifolds. The seven-dimensional space, whose base is a complex line bundle over S 2 x S 2 , is discussed in detail since it has relevance in terms of the AdS/CFT correspondence

  13. The world-line. Albert Einstein and modern physics

    International Nuclear Information System (INIS)

    Maalampi, Jukka

    2008-01-01

    This book is an entertaining and formula-free presentation of modern physics from the 19th century to present. The life of Albert Einstein and his scientific works are drawn as red fathom through the text. The author explains central terms and results of modern physics in populary-scientific form from the historical perspective. To the reader in humorous form an imagination is mediated how modern physics has been developed. We learn from the exciting effects of the ether, we hear from faraday and magnetic needles, from Maxwell's prediction of the electromagnetic waves, from heinrich Hertz and from the photoelectric effect. Was the Michelson-Morley experiment a measurement success or an unsuccess? Why has Einstein abandoned the ether? How has Einstein in the miraculous year 1905 revolutionated physics and why he has begged Newton for excusement? Exist atoms? What is motion? What is light and what is to be understood under ''now'' and ''here''? Light deviation or non-deviation? How act the tidal forces? And above all: How has Einstein answered these questions. We meet Poincare, Lorentz and Hilbert, Boltzmann and Bohr, Minkowski, Planck, de Broglie, Hubble and Weyl, Gamow, Hahn and Meitner, Kapiza and Landau, Fermi and many other famous scientists. What had Eddington against Chandrasekhar and what had Einstein against black holes? Why should space tourists and dream tourists make holiday not on the Loch Ness but on the safe side of a black hole? Why inveighed Pauli against Einstein? Is the concern with the atomic-bomb formula right? Smeared matter, big bang and cosmic background radiation, gravitational waves and double pulsars, the cosmological constant and the expansion of the universe are further themes, which keep the reader in breath and let no mental vacuum arise [de

  14. CP violation and modular symmetries

    OpenAIRE

    Dent, Thomas

    2001-01-01

    We reconsider the origin of CP violation in fundamental theory. Existing string models of spontaneous CP violation make ambiguous predictions, due to the arbitrariness of CP transformation and the apparent non-invariance of the results under duality. We find an unambiguous modular CP invariance condition, applicable to predictive models of spontaneous CP violation, which circumvents these problems; it strongly constrains CP violation by heterotic string moduli. The dilaton is also evaluated a...

  15. Einstein's Annalen Papers: The Complete Collection 1901 - 1922

    Science.gov (United States)

    Renn, Jürgen

    2005-05-01

    In 1905, Einstein's Annus Mirabilis, Albert Einstein made three discoveries concerning the foundations of nature which form the basis of his fame as a physicist. These revolutionary papers on the light-quantum hypothesis, Brownian motion, and special relativity, were published in the journal "Annalen der Physik". All three are now established as pillars of modern science and its applications in technology and are an indispensable part of the modern world. This volume presents some of the most significant original papers which Albert Einstein ever wrote. It includes the facsimiles of the three revolutionary papers of 1905. In addition it contains papers which show the consequences of the ground-breaking ideas of these seminal papers from E=mc² to the quantum theory of specific heats. It also features Einstein's first exposition of his new general theory of relativity. Introducing the original German papers the science historians Jürgen Renn (MPI for the History of Science, Berlin), David C. Cassidy (Hofstra University, Hempstead), Michel Janssen (University of Minnesota), and Robert Rynasiewicz (John Hopkins University) complement and comment the collection with topical articles.

  16. Einstein and interpretation of quantum field theory

    International Nuclear Information System (INIS)

    Kashlyun, F.

    1982-01-01

    The main problems of the quantum theory, the basis of which was laid by Planck in 1900 as a result of the discovery of elementary quantum of action, are examined. The most important Einstein contributions to the quantum theory are enumerated. The Einstein work about the light quanta, proved wave-particle dualism, stated one of the most complicated problems to the physics. The work on the specific heat capacity of solids shows that the quantum theory should be beyond the limits of the narrow range of the problems on black radiation. The works on the equilibrium of radiation have convincingly demonstrates statistical character of the radiation processes and have marked the way to Heizenberg form of the quantum mechanics. Einstein generalized the idea of wave-particle dualism to the ordinary gas. It helped to prepare the Schroedinger form of quantum mechanics

  17. More accurate theory for Bose-Einstein condensation fraction

    International Nuclear Information System (INIS)

    Biswas, Shyamal

    2008-01-01

    Bose-Einstein statistics is derived in the thermodynamic limit when the ratio of system size to thermal de Broglie wavelength goes to infinity. However, according to the experimental setup of Bose-Einstein condensation of harmonically trapped Bose gas of alkali atoms, the ratio near the condensation temperature (T o ) is 30-50. And, at ultralow temperatures well below T o , this ratio becomes comparable to 1. We argue that finite size as well as the ultralow temperature induces corrections to Bose-Einstein statistics. From the corrected statistics we plot condensation fraction versus temperature graph. This theoretical plot satisfies well with the experimental plot [A. Griesmaier et al., Phys. Rev. Lett. 94 (2005) 160401

  18. Estudio comparativo de flujo de fluido a través de una placa de orificio usando las ecuaciones de Stokes y de Navier-Stokes

    Directory of Open Access Journals (Sweden)

    Miryam Lucía Guerra-Mazo

    2016-05-01

    Full Text Available Presenta los resultados de la comparación entre las ecuaciones de Stokes y de Navier-Stokes para la simulación del flujo de agua líquida, a condiciones atmosféricas, a través de una placa orificio concéntrica. A partir de los datos experimentales que fueron tomados en el banco de fluidos, se evaluaron las simulaciones de ambas ecuaciones, usando el software libre Freefem++cs, que se basa en el método de los elementos finitos; las variables evaluadas son velocidad y presión en un intervalo de tiempo. Al analizar los resultados obtenidos con las simulaciones y comparar con los datos experimentales se encontró que las ecuaciones de Navier-Stokes representan mejor el sistema que la ecuación de Stokes.

  19. Optical absorption in a degenerate Bose-Einstein gas

    International Nuclear Information System (INIS)

    Yip, S.K.

    2002-01-01

    We develop a theory on optical absorption in a dilute Bose-Einstein gas at low temperatures. This theory is motivated by the Bogoliubov theory of elementary excitations for this system, and takes into account explicitly the modification of the nature and dispersion of elementary excitations due to Bose-Einstein condensation. Our results show important differences from existing theories

  20. Fragility and hysteretic creep in frictional granular jamming.

    Science.gov (United States)

    Bandi, M M; Rivera, M K; Krzakala, F; Ecke, R E

    2013-04-01

    The granular jamming transition is experimentally investigated in a two-dimensional system of frictional, bidispersed disks subject to quasistatic, uniaxial compression without vibrational disturbances (zero granular temperature). Three primary results are presented in this experimental study. First, using disks with different static friction coefficients (μ), we experimentally verify numerical results that predict jamming onset at progressively lower packing fractions with increasing friction. Second, we show that the first compression cycle measurably differs from subsequent cycles. The first cycle is fragile-a metastable configuration with simultaneous jammed and unjammed clusters-over a small packing fraction interval (φ(1)disk displacements over the same packing fraction interval. This fragile behavior is explained through a percolation mechanism of stressed contacts where cluster growth exhibits spatial correlation with disk displacements and contributes to recent results emphasizing fragility in frictional jamming. Control experiments show that the fragile state results from the experimental incompatibility between the requirements for zero friction and zero granular temperature. Measurements with several disk materials of varying elastic moduli E and friction coefficients μ show that friction directly controls the start of the fragile state but indirectly controls the exponential pressure rise. Finally, under repetitive loading (compression) and unloading (decompression), we find the system exhibits pressure hysteresis, and the critical packing fraction φ(c) increases slowly with repetition number. This friction-induced hysteretic creep is interpreted as the granular pack's evolution from a metastable to an eventual structurally stable configuration. It is shown to depend on the quasistatic step size Δφ, which provides the only perturbative mechanism in the experimental protocol, and the friction coefficient μ, which acts to stabilize the pack.

  1. Coherence, Abstraction, and Personal Involvement: Albert Einstein, Physicist and Humanist.

    Science.gov (United States)

    Ne'eman, Yuval

    1979-01-01

    Reviews Einstein's main contributions to physics, and analyzes the importance of a coherent body of theory. Einstein's involvement in nonscientific issues such as nuclear disarmament is also included. (HM)

  2. Obesity, Food Selectivity, and Physical Activity in Individuals with Fragile X Syndrome

    Science.gov (United States)

    Raspa, Melissa; Bailey, Donald B., Jr.; Bishop, Ellen; Holiday, David; Olmsted, Murrey

    2010-01-01

    National survey data from 884 families were used to examine the overall health of children and adults with fragile X syndrome. Results indicate the rate of obesity in adults with fragile X syndrome is similar to the general population (30%). Male children with fragile X syndrome, however, had higher rates of obesity (31%) when compared with…

  3. Ectodermal dysplasia-skin fragility syndrome: A rare case report

    Directory of Open Access Journals (Sweden)

    Subhash Kashyap

    2015-01-01

    Full Text Available Ectodermal dysplasia/skin fragility syndrome (ED-SFS is a newly described autosomal recessive disorder characterized by skin fragility and blistering, palmoplantar keratoderma, abnormal hair growth, nail dystrophy, and occasionally defective sweating. It results from mutations in the PKP1 gene encoding plakophilin 1 (PKP1, which is an important component of stratifying epithelial desmosomes and a nuclear component of many cell types. Only 12 cases of this rare genodermatosis have been reported so far. We present an unusual case of ED-SFS in a 12-year boy who was normal at birth but subsequently developed skin fragility, hair and nail deformities, abnormal dentition, palmoplantar keratoderma, and abnormal sweating but no systemic abnormality.

  4. Sasaki-Einstein Manifolds and Volume Minimisation

    CERN Document Server

    Martelli, D; Yau, S T; Martelli, Dario; Sparks, James; Yau, Shing-Tung

    2006-01-01

    We study a variational problem whose critical point determines the Reeb vector field for a Sasaki-Einstein manifold. This extends our previous work on Sasakian geometry by lifting the condition that the manifolds are toric. We show that the Einstein-Hilbert action, restricted to a space of Sasakian metrics on a link L in a Calabi-Yau cone M, is the volume functional, which in fact is a function on the space of Reeb vector fields. We relate this function both to the Duistermaat-Heckman formula and also to a limit of a certain equivariant index on M that counts holomorphic functions. Both formulae may be evaluated by localisation. This leads to a general formula for the volume function in terms of topological fixed point data. As a result we prove that the volume of any Sasaki-Einstein manifold, relative to that of the round sphere, is always an algebraic number. In complex dimension n=3 these results provide, via AdS/CFT, the geometric counterpart of a-maximisation in four dimensional superconformal field theo...

  5. Bose-Einstein condensation of paraxial light

    Science.gov (United States)

    Klaers, J.; Schmitt, J.; Damm, T.; Vewinger, F.; Weitz, M.

    2011-10-01

    Photons, due to the virtually vanishing photon-photon interaction, constitute to very good approximation an ideal Bose gas, but owing to the vanishing chemical potential a (free) photon gas does not show Bose-Einstein condensation. However, this is not necessarily true for a lower-dimensional photon gas. By means of a fluorescence induced thermalization process in an optical microcavity one can achieve a thermal photon gas with freely adjustable chemical potential. Experimentally, we have observed thermalization and subsequently Bose-Einstein condensation of the photon gas at room temperature. In this paper, we give a detailed description of the experiment, which is based on a dye-filled optical microcavity, acting as a white-wall box for photons. Thermalization is achieved in a photon number-conserving way by photon scattering off the dye molecules, and the cavity mirrors both provide an effective photon mass and a confining potential-key prerequisites for the Bose-Einstein condensation of photons. The experimental results are in good agreement with both a statistical and a simple rate equation model, describing the properties of the thermalized photon gas.

  6. Optimal distribution of integration time for intensity measurements in Stokes polarimetry.

    Science.gov (United States)

    Li, Xiaobo; Liu, Tiegen; Huang, Bingjing; Song, Zhanjie; Hu, Haofeng

    2015-10-19

    We consider the typical Stokes polarimetry system, which performs four intensity measurements to estimate a Stokes vector. We show that if the total integration time of intensity measurements is fixed, the variance of the Stokes vector estimator depends on the distribution of the integration time at four intensity measurements. Therefore, by optimizing the distribution of integration time, the variance of the Stokes vector estimator can be decreased. In this paper, we obtain the closed-form solution of the optimal distribution of integration time by employing Lagrange multiplier method. According to the theoretical analysis and real-world experiment, it is shown that the total variance of the Stokes vector estimator can be significantly decreased about 40% in the case discussed in this paper. The method proposed in this paper can effectively decrease the measurement variance and thus statistically improves the measurement accuracy of the polarimetric system.

  7. Polarization speckles and generalized Stokes vector wave: a review [invited

    DEFF Research Database (Denmark)

    Takeda, Mitsuo; Wang, Wei; Hanson, Steen Grüner

    2010-01-01

    We review some of the statistical properties of polarization-related speckle phenomena, with an introduction of a less known concept of polarization speckles and their spatial degree of polarization. As a useful means to characterize twopoint vector field correlations, we review the generalized...... Stokes parameters proposed by Korotkova and Wolf, and introduce its time-domain representation to describe the space-time evolution of the correlation between random electric vector fields at two different space-time points. This time-domain generalized Stokes vector, with components similar to those...... of the beam coherence polarization matrix proposed by Gori, is shown to obey the wave equation in exact analogy to a coherence function of scalar fields. Because of this wave nature, the time-domain generalized Stokes vector is referred to as generalized Stokes vector wave in this paper....

  8. Franz Selety (1893-1933?). His cosmological investigations and the correspondence with Einstein (German Title: Franz Selety (1893-1933?). Seine kosmologischen Arbeiten und der Briefwechsel mit Einstein)

    Science.gov (United States)

    Jung, Tobias

    In 1922, Franz Selety, university-bred philosopher and self-educated physicist and cosmologist, developed a molecular hierarchical, spatially infinite, Newtonian cosmological model. His considerations were based on his earlier philosophical work published in 1914 as well as on the early correspondence with Einstein in 1917. Historically, the roots of hierarchical models can be seen in 18th century investigations by Thomas Wright of Durham, Immanuel Kant and Johann Heinrich Lambert. Those investigations were taken up by Edmund Fournier d'Albe and Carl Charlier at the beginning of the 20th century. Selety's cosmological model was criticized by Einstein mainly due to its spatial infiniteness which in Einstein's opinion seemed to contradict Mach's principle. This criticism sheds light on Einstein's conviction that with his first cosmological model, namely the static, spatially infinite, though unbounded Einstein Universe of 1917, the appropriate cosmological theory already had been established.

  9. Spatial entanglement patterns and Einstein-Podolsky-Rosen steering in Bose-Einstein condensates.

    Science.gov (United States)

    Fadel, Matteo; Zibold, Tilman; Décamps, Boris; Treutlein, Philipp

    2018-04-27

    Many-particle entanglement is a fundamental concept of quantum physics that still presents conceptual challenges. Although nonclassical states of atomic ensembles were used to enhance measurement precision in quantum metrology, the notion of entanglement in these systems was debated because the correlations among the indistinguishable atoms were witnessed by collective measurements only. Here, we use high-resolution imaging to directly measure the spin correlations between spatially separated parts of a spin-squeezed Bose-Einstein condensate. We observe entanglement that is strong enough for Einstein-Podolsky-Rosen steering: We can predict measurement outcomes for noncommuting observables in one spatial region on the basis of corresponding measurements in another region with an inferred uncertainty product below the Heisenberg uncertainty bound. This method could be exploited for entanglement-enhanced imaging of electromagnetic field distributions and quantum information tasks. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  10. On some types of exact solutions of the Einstein equation. 2

    International Nuclear Information System (INIS)

    Obukhov, V.V.

    1978-01-01

    Several types of the Einstein spaces which can describe gravitational waves are investigated. When the solutions of the Einstein equations are found, additional conditions are imposed on the metrics under consideration. It is required: 1) that the spaces should admit the two-parametric Abelian group of motion; 2) that the wave coordinate system would be privileged; 3) that bicharacteristics of the Einstein equation would satisfy the harmonicity condition. The superposition of the enumerated conditions has made it possible to perform a complete integration of the Einstein equations. The solutions obtained are interpreted as the wave ones

  11. The Influence of Ernst Mach and Ludwig Boltzmann on Albert Einstein

    International Nuclear Information System (INIS)

    Broda, E.

    1979-01-01

    This document, written by Engelbert Broda in 1979, analyses the influence of Ernst Mach and Ludwig Boltzmann on Albert Einstein. Broda describes how Einstein and his scientific thinking benefited from Mach’s criticism on classical mechanics and its basic concepts like absolute time and absolute space. This criticism encouraged Einstein in the time he worked on his special relativity. On the other side Broda writes about the influence of Ludwig Boltzman, an atomist, whose scientific work and research prepared the ground for Einsteins work on the quantum-structure of electromagnetic radiation or the discovery of the photoelectric effect. (nowak)

  12. Extrinsic CPT Violation in Neutrino Oscillations

    International Nuclear Information System (INIS)

    Ohlsson, Tommy

    2004-01-01

    In this talk, we investigate extrinsic CPT violation in neutrino oscillations in matter with three flavors. Note that extrinsic CPT violation is different from intrinsic CPT violation. Extrinsic CPT violation is one way of quantifying matter effects, whereas intrinsic CPT violation would mean that the CPT invariance theorem is not valid. We present analytical formulas for the extrinsic CPT probability differences and discuss their implications for long-baseline experiments and neutrino factory setups

  13. Fragility Analysis of Concrete Gravity Dams

    Science.gov (United States)

    Tekie, Paulos B.; Ellingwood, Bruce R.

    2002-09-01

    Concrete gravity dams are an important part ofthe nation's infrastructure. Many dams have been in service for over 50 years, during which time important advances in the methodologies for evaluation of natural phenomena hazards have caused the design-basis events to be revised upwards, in some cases significantly. Many existing dams fail to meet these revised safety criteria and structural rehabilitation to meet newly revised criteria may be costly and difficult. A probabilistic safety analysis (PSA) provides a rational safety assessment and decision-making tool managing the various sources of uncertainty that may impact dam performance. Fragility analysis, which depicts fl%e uncertainty in the safety margin above specified hazard levels, is a fundamental tool in a PSA. This study presents a methodology for developing fragilities of concrete gravity dams to assess their performance against hydrologic and seismic hazards. Models of varying degree of complexity and sophistication were considered and compared. The methodology is illustrated using the Bluestone Dam on the New River in West Virginia, which was designed in the late 1930's. The hydrologic fragilities showed that the Eluestone Dam is unlikely to become unstable at the revised probable maximum flood (PMF), but it is likely that there will be significant cracking at the heel ofthe dam. On the other hand, the seismic fragility analysis indicated that sliding is likely, if the dam were to be subjected to a maximum credible earthquake (MCE). Moreover, there will likely be tensile cracking at the neck of the dam at this level of seismic excitation. Probabilities of relatively severe limit states appear to be only marginally affected by extremely rare events (e.g. the PMF and MCE). Moreover, the risks posed by the extreme floods and earthquakes were not balanced for the Bluestone Dam, with seismic hazard posing a relatively higher risk.

  14. Einstein, Schwarzschild, the Perihelion Motion of Mercury and the Rotating Disk Story

    OpenAIRE

    Weinstein, Galina

    2014-01-01

    On November 18, 1915 Einstein reported to the Prussian Academy that the perihelion motion of Mercury is explained by his new General Theory of Relativity: Einstein found approximate solutions to his November 11, 1915 field equations. Einstein's field equations cannot be solved in the general case, but can be solved in particular situations. The first to offer such an exact solution was Karl Schwarzschild. Schwarzschild found one line element, which satisfied the conditions imposed by Einstein...

  15. Ectodermal Dysplasia Skin Fragility Syndrome

    Directory of Open Access Journals (Sweden)

    Ayça Alan Atalay

    2014-06-01

    Full Text Available Ectodermal dysplasia-skin fragility syndrome (EDSFS is a rare autosomal recessive genodermatosis first described in 1997 by Mc Grath. EDSFS results from loss of function mutations in plakophilin-1 (PKP1. PKP1 is a structural component of desmosomes, cellcell adhesion complexes. It is also found as a nuclear protein in several cell types that are lack of desmosomes. In skin, however, PKP1 expression is confined mainly to suprabasal keratinocytes and the outer root sheath of hair follicules. Loss of function mutation in PKP1 leads to extensive skin fragility, bullae and erosions following minor trauma, focal keratoderma with painful fissures, alopecia, and nail dystrophy. In some patients hypohidrosis may also be seen. EDSFS is now considered as a specific suprabasal form of epidermolysis bullosa simplex. In this report we describe a 20 year old EDSFS case.

  16. Albert Einstein and his mentor Max Talmey. The seventh Charles B. Snyder Lecture.

    Science.gov (United States)

    Ravin, J G

    1997-01-01

    While he was a student at the Munich medical school, Max Talmey strongly influenced the education of Albert Einstein. Their association occurred during five years of Einstein's second decade. They lost contact for many years after each left Munich. Talmey emigrated to the United States and practiced medicine, mainly ophthalmology, in New York City. He made significant contributions to medicine, to the popularization of Einstein's work, and to the development of international languages. The relationship of Talmey and Einstein was rekindled when Einstein visited and later moved to the United States.

  17. A class of exact solutions to the Einstein field equations

    International Nuclear Information System (INIS)

    Goyal, Nisha; Gupta, R K

    2012-01-01

    The Einstein-Rosen metric is considered and a class of new exact solutions of the field equations for stationary axisymmetric Einstein-Maxwell fields is obtained. The Lie classical approach is applied to obtain exact solutions. By using the Lie classical method, we are able to derive symmetries that are used for reducing the coupled system of partial differential equations into ordinary differential equations. From reduced differential equations we have derived some new exact solutions of Einstein-Maxwell equations. (paper)

  18. Time symmetry and the Einstein paradox

    International Nuclear Information System (INIS)

    Costa de Beauregard, O.

    1977-01-01

    The characteristic difference between the paleoquantal calculation (addition of partial probabilities) and the neoquantal one (addition of partial amplitudes) for the correlation of photon polarizations in cascade transitions is derived in terms of elementary trigonometry. This deliberate use of simple formulae aims at a transparent rendering of the change in paradigm required by the so-called EPR paradox (which is truly the 1927 Einstein paradox), namely that 1) the two photons do not possess polarizations of their own when leaving the source C, but borrow one later, when interacting with the analysers L and N; 2) the die is thus not cast at C, but later, at L and N; 3) the correlation between the measurements at L and N is tied through C, in their common past. The tight connection between this ''Einstein nonseparability'' and the nonlocality in Feynman's ''theory of positrons'' is demonstrated through an analysis of the e + e - annihilation into two photons. Thus the Einstein paradox corresponds, in the ''new wavelike probability calculus'', to the Loschmid and Zermelo sort of paradox in the old probability calculus. That is, it contrasts the intrinsic time symmetry existing at the elementary level to the factlike macroscopic time asymmetry. The discussion deliberately by-passes the hidden-variable problem, the model in this being Einstein's by-passing of the mechanical aether when proposing special relativity. It is believed today, like in 1905, the problem is tayloring the wording after the (operationally good) mathematics. Moreover, that the change in paradigm, which is needed, comes through a victory of formalism over modelism. (author)

  19. Optimal control of compressible Navier-Stokes equations

    International Nuclear Information System (INIS)

    Ito, K.; Ravindran, S.S.

    1994-01-01

    Optimal control for the viscous incompressible flows, which are governed by incompressible Navier-Stokes equations, has been the subject of extensive study in recent years, see, e.g., [AT], [GHS], [IR], and [S]. In this paper we consider the optimal control of compressible isentropic Navier-Stokes equations. We develop the weak variational formulation and discuss the existence and necessary optimality condition characterizing the optimal control. A numerical method based on the mixed-finite element method is also discussed to compute the control and numerical results are presented

  20. Measurement of the Stokes parameters of light

    International Nuclear Information System (INIS)

    Berry, H.G.; Gabrielse, G.; Livingston, A.E.

    1977-01-01

    We describe a measuring system for determing the state of polarization of a beam of light in terms of its Stokes parameters. The technique which can be fully automated incorporates a monochromator and single photon counting detection and can thus be applied over a large wavelength range for very weak optical signals. Fourier transformation of the data by an on-line minicomputer allows immediate calculation of the Stokes parameters. We discuss special applications to light emitted from excited atomic systems with and without cylindrical symmetry

  1. Calculation of thermodynamic properties of finite Bose-Einstein systems

    NARCIS (Netherlands)

    Borrmann, P.; Harting, J.D.R.; Mülken, O.; Hilf, E.

    1999-01-01

    We derive an exact recursion formula for the calculation of thermodynamic functions of finite systems obeying Bose-Einstein statistics. The formula is applicable for canonical systems where the particles can be treated as noninteracting in some approximation, e.g., like Bose-Einstein condensates in

  2. From Newton to Einstein.

    Science.gov (United States)

    Ryder, L. H.

    1987-01-01

    Discusses the history of scientific thought in terms of the theories of inertia and absolute space, relativity and gravitation. Describes how Sir Isaac Newton used the work of earlier scholars in his theories and how Albert Einstein used Newton's theories in his. (CW)

  3. Inviscid limit of stochastic damped 2D Navier–Stokes equations

    International Nuclear Information System (INIS)

    Bessaih, Hakima; Ferrario, Benedetta

    2014-01-01

    We consider the inviscid limit of the stochastic damped 2D Navier–Stokes equations. We prove that, when the viscosity vanishes, the stationary solution of the stochastic damped Navier–Stokes equations converges to a stationary solution of the stochastic damped Euler equation and that the rate of dissipation of enstrophy converges to zero. In particular, this limit obeys an enstrophy balance. The rates are computed with respect to a limit measure of the unique invariant measure of the stochastic damped Navier–Stokes equations. (paper)

  4. CP-violations in B decays

    Indian Academy of Sciences (India)

    Recent results on CP-violation measurements in decays from energy asymmetric -factory experiments are reported. Thanks to large accumulated data samples, CP-violations in decays in mixing-decay interference and direct CP-violation are now firmly established. The measurements of three angles of the unitarity ...

  5. Analysing the Effect on CMB in a Parity and Charge Parity Violating Varying Alpha Theory

    Energy Technology Data Exchange (ETDEWEB)

    Maity, Debaprasad; /NCTS, Taipei /Taiwan, Natl. Taiwan U.; Chen, Pisin; /NCTS, Taipei /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC

    2012-09-14

    In this paper we study in detail the effect of our recently proposed model of parity and charge-parity (PCP) violating varying alpha on the Cosmic Microwave Background (CMB) photon passing through the intra galaxy-cluster medium (ICM). The ICM is well known to be composed of magnetized plasma. According to our model, the polarization and intensity of the CMB would be affected when traversing through the ICM due to non-trivial scalar photon interactions. We have calculated the evolution of such polarization and intensity collectively, known as the stokes parameters of the CMB photon during its journey through the ICM and tested our results against the Sunyaev-Zel'dovich (SZ) measurement on Coma galaxy cluster. Our model contains a PCP violating parameter, {beta}, and a scale of alpha variation {omega}. Using the derived constrained on the photon-to-scalar conversion probability, {bar P}{sub {gamma}{yields}{phi}}, for Coma cluster in ref.[34] we found a contour plot in the ({omega},{beta}) parameter plane. The {beta} = 0 line in this parameter space corresponds to well-studied Maxwell-dilaton type models which has lower bound on {omega} {approx}> 6.4 x 10{sup 9} GeV. In general, as the absolute value of {beta} increases, lower bound on {omega} also increases. Our model in general predicts the modification of the CMB polarization with a non-trivial dependence on the parity violating coupling parameter {beta}. However, it is unconstrained in this particular study. We show that this effect can in principle be detected in the future measurements on CMB polarization such that {beta} can also be constrained.

  6. International Companies in Fragile States

    DEFF Research Database (Denmark)

    Patey, Luke; Kragelund, Peter

    Denmark must not fail to promote corporate social responsibility in fragile states. International companies remain active in these environments, and often worsen rather than alleviate poor governance. Financial transparency and human rights initiatives offer the first step in ensuring...

  7. q-deformed Einstein's model to describe specific heat of solid

    Science.gov (United States)

    Guha, Atanu; Das, Prasanta Kumar

    2018-04-01

    Realistic phenomena can be described more appropriately using generalized canonical ensemble, with proper parameter sets involved. We have generalized the Einstein's theory for specific heat of solid in Tsallis statistics, where the temperature fluctuation is introduced into the theory via the fluctuation parameter q. At low temperature the Einstein's curve of the specific heat in the nonextensive Tsallis scenario exactly lies on the experimental data points. Consequently this q-modified Einstein's curve is found to be overlapping with the one predicted by Debye. Considering only the temperature fluctuation effect(even without considering more than one mode of vibration is being triggered) we found that the CV vs T curve is as good as obtained by considering the different modes of vibration as suggested by Debye. Generalizing the Einstein's theory in Tsallis statistics we found that a unique value of the Einstein temperature θE along with a temperature dependent deformation parameter q(T) , can well describe the phenomena of specific heat of solid i.e. the theory is equivalent to Debye's theory with a temperature dependent θD.

  8. Robust-yet-fragile nature of interdependent networks

    Science.gov (United States)

    Tan, Fei; Xia, Yongxiang; Wei, Zhi

    2015-05-01

    Interdependent networks have been shown to be extremely vulnerable based on the percolation model. Parshani et al. [Europhys. Lett. 92, 68002 (2010), 10.1209/0295-5075/92/68002] further indicated that the more intersimilar networks are, the more robust they are to random failures. When traffic load is considered, how do the coupling patterns impact cascading failures in interdependent networks? This question has been largely unexplored until now. In this paper, we address this question by investigating the robustness of interdependent Erdös-Rényi random graphs and Barabási-Albert scale-free networks under either random failures or intentional attacks. It is found that interdependent Erdös-Rényi random graphs are robust yet fragile under either random failures or intentional attacks. Interdependent Barabási-Albert scale-free networks, however, are only robust yet fragile under random failures but fragile under intentional attacks. We further analyze the interdependent communication network and power grid and achieve similar results. These results advance our understanding of how interdependency shapes network robustness.

  9. Einstein une biographie dessinée

    CERN Document Server

    Maier, Corinne

    2015-01-01

    « Je m'appelle Albert Einstein. En voulant comprendre l'univers, j'ai libéré des forces de destruction terrifiantes. Mais il faut continuer à chercher le grand secret du cosmos. » Albert Einstein (1879-1955) est un immense génie devenu, sans le vouloir, une star de la science. Avec ses théories de la relativité restreinte puis de la relativité générale, il a radicalement transformé nos vies. Voici le récit de son existence passionnée et de ses contributions fondamentales.

  10. Albert Einstein's 1916 Review Article on General Relativity

    OpenAIRE

    Sauer, Tilman

    2004-01-01

    The first comprehensive overview of the final version of the general theory of relativity was published by Einstein in 1916 after several expositions of preliminary versions and latest revisions of the theory in November 1915. A historical account of this review paper is given, of its prehistory, including a discussion of Einstein's collaboration with Marcel Grossmann, and of its immediate reception.

  11. Generation of static solutions of self-consistent system of Einstein-Maxwell equations

    International Nuclear Information System (INIS)

    Anchikov, A.M.; Daishev, R.A.

    1988-01-01

    The theorem, according to which the static solution of the self-consistent system of the Einstein-Maxwell equations is assigned to energy static solution of the Einstein equations with the arbitrary energy-momentum tensor in the right part, is proved. As a consequence of this theorem, the way of the generation of the static solutions of the self-consistent system of the Einstein-Maxwell equations with charged dust as a source of the vacuum solutions of the Einstein equations is shown

  12. Einstein-Podolsky-Rosen entanglement and steering in two-well Bose-Einstein-condensate ground states

    Science.gov (United States)

    He, Q. Y.; Drummond, P. D.; Olsen, M. K.; Reid, M. D.

    2012-08-01

    We consider how to generate and detect Einstein-Podolsky-Rosen (EPR) entanglement and the steering paradox between groups of atoms in two separated potential wells in a Bose-Einstein condensate. We present experimental criteria for this form of entanglement and propose experimental strategies for detecting entanglement using two- or four-mode ground states. These approaches use spatial and/or internal modes. We also present higher-order criteria that act as signatures to detect the multiparticle entanglement present in this system. We point out the difference between spatial entanglement using separated detectors and other types of entanglement that do not require spatial separation. The four-mode approach with two spatial and two internal modes results in an entanglement signature with spatially separated detectors, conceptually similar to the original EPR paradox.

  13. Einstein-Weyl spaces and third-order differential equations

    Science.gov (United States)

    Tod, K. P.

    2000-08-01

    The three-dimensional null-surface formalism of Tanimoto [M. Tanimoto, "On the null surface formalism," Report No. gr-qc/9703003 (1997)] and Forni et al. [Forni et al., "Null surfaces formation in 3D," J. Math Phys. (submitted)] are extended to describe Einstein-Weyl spaces, following Cartan [E. Cartan, "Les espaces généralisées et l'integration de certaines classes d'equations différentielles," C. R. Acad. Sci. 206, 1425-1429 (1938); "La geometria de las ecuaciones diferenciales de tercer order," Rev. Mat. Hispano-Am. 4, 1-31 (1941)]. In the resulting formalism, Einstein-Weyl spaces are obtained from a particular class of third-order differential equations. Some examples of the construction which include some new Einstein-Weyl spaces are given.

  14. CP violation in B decays

    International Nuclear Information System (INIS)

    Kayser, B.

    1990-01-01

    The study of CP-violating effects in B decays will be a good test of whether CP violation is caused by the known weak interaction. If this is its origin, then large, cleanly-predicted CP-violating effects are expected in certain neutral B decays to hadronic CP eigenstates. The phenomenology of CP violation in the B system is reviewed, and the genesis of these large effects is explained. In this it is shown that large, cleanly-predicted effects are also expected in some decays to states which are not CP eigenstates. The combined study of the latter decays and those to CP eigenstates may make it possible to obtain a statistically-significant CP-violating signal with fewer B mesons that would otherwise be required

  15. Implications of Navier-Stokes turbulence theory for plasma turbulence

    International Nuclear Information System (INIS)

    Montgomery, David

    1977-01-01

    A brief discussion of Navier-Stokes turbulence theory is given with particular reference to the two dimensional case. The MHD turbulence is introduced with possible applications of techniques developed in Navier-Stokes theory. Turbulence in Vlasov plasma is also discussed from the point of view of the ''direct interaction approximation'' (DIA). (A.K.)

  16. Nonlocality of a single photon: Paths to an Einstein-Podolsky-Rosen-steering experiment

    International Nuclear Information System (INIS)

    Jones, S. J.; Wiseman, H. M.

    2011-01-01

    A single-photon incident on a beam splitter produces an entangled field state, and in principle could be used to violate a Bell inequality, but such an experiment (without postselection) is beyond the reach of current experiments. Here we consider the somewhat simpler task of demonstrating Einstein-Podolsky-Rosen (EPR) steering with a single photon (also without postselection). We demonstrate that Alice's choice of measurement on her portion of the entangled state can affect Bob's portion of the entangled state in his laboratory, in a sense rigorously defined by us and Doherty [Phys. Rev. Lett. 98, 140402 (2007)]. Previous work by Lvovsky and coworkers [Phys. Rev. Lett. 92, 047903 (2004)] has addressed this phenomenon (which they called remote preparation) experimentally using homodyne measurements on a single photon. Here we show that, unfortunately, their experimental parameters do not meet the bounds necessary for a rigorous demonstration of EPR steering with a single photon. However, we also show that modest improvements in the experimental parameters, and the addition of photon counting to the arsenal of Alice's measurements, would be sufficient to allow such a demonstration.

  17. Speeded Recognition of Ungrammaticality: Double Violations.

    Science.gov (United States)

    Moore, Timothy E.; Biederman, Irving

    1979-01-01

    The speed at which sentences with various kinds of violations could be rejected was studied. Compatible with the sequential model was the finding that noun-verb and adjective-noun double violations did not result in shorter reaction times than noun-verb single violations, although double violations were judged less acceptable. (Author/RD)

  18. Beautiful CP violation

    International Nuclear Information System (INIS)

    Dunietz, I.

    1997-01-01

    CP violation is observed to date only in K 0 decays and is parameterizable by a single quantity ε. Because it is one of the least understood phenomena in the Standard Model and holds a clue to baryogenesis, it must be investigated further. Highly specialized searches in K 0 decays are possible. Effects in B decays are much larger. In addition to the traditional B d → J/ψK S , π + π - asymmetries, CP violation could be searched for in already existing inclusive B data samples. The rapid B s --anti B s oscillations cancel in untagged B s data samples, which therefore allow feasibility studies for the observation of CP violation and the extraction of CKM elements with present vertex detectors. The favored method for the extraction of the CKM angle γ is shown to be unfeasible and a solution is presented involving striking direct CP violation in charged B decays. Novel methods for determining the B s mixing parameter Δm are described without the traditional requirement of flavor-specific final states

  19. Epidemiology of "fragile skin": results from a survey of different skin types

    Directory of Open Access Journals (Sweden)

    Haftek M

    2013-12-01

    Full Text Available Marek Haftek,1 Christine Coutanceau,2 Charles Taïeb3 1Université Lyon 1, Laboratoire de Recherche Dermatologique, Faculté de Médecine et de Pharmacie, Lyon, 2Département Médical, Laboratoires Dermatologiques A-Derma, Lavaur, 3Public Health, Pierre Fabre SA, Paris, France Background: Epidemiologic information regarding the prevalence of "fragile skin" in different adult populations is currently limited. The objective of the current survey was to assess the occurrence of perceived "fragile skin" across different skin types in the general adult population. Methods: Individuals aged 15–65 years from five representative geographic regions (France, Spain, Sweden, Japan, and the US were interviewed and grouped into the following skin types: Caucasian North skin (n=1,218, Caucasian South skin (n=1,695, Asian skin (n=1,500, and Black skin (n=500. The main survey question was "In your opinion, do you have fragile skin?" Concepts relating to the nature and appearance of an individual's skin were also evaluated. Results: A total of 4,913 individuals were interviewed. Subjects in the Caucasian North, Caucasian South, Asian, and Black skin type groups responded positively to the question "In your opinion, do you have fragile skin?" in the following proportions: 24.44%, 29.71%, 52.67%, and 42.20%, respectively. With the exception of individuals in the Black skin group, "fragile skin" was prevalent in significantly more women than men (P<0.0001. Compared with other age categories, the prevalence of "fragile skin" was significantly higher in individuals aged 15–34 years (P<0.0001, regardless of skin type. In general, individuals reporting "fragile skin" were 2–3-fold more likely to respond positively to a series of questions relating to the nature and appearance of their skin. The prevalence of "fragile skin" was also higher in individuals who experienced dermatosis (skin lesions of any type in the previous 12 months. Conclusion: Whilst these

  20. Relativity and Gravitation : 100 Years After Einstein in Prague

    CERN Document Server

    Ledvinka, Tomáš; General Relativity, Cosmology and Astrophysics : Perspectives 100 Years After Einstein's Stay in Prague

    2014-01-01

    In early April 1911 Albert Einstein arrived in Prague to become full professor of theoretical physics at the German part of Charles University. It was there, for the first time, that he concentrated primarily on the problem of gravitation. Before he left Prague in July 1912 he had submitted the paper “Relativität und Gravitation: Erwiderung auf eine Bemerkung von M. Abraham” in which he remarkably anticipated what a future theory of gravity should look like. At the occasion of the Einstein-in-Prague centenary an international meeting was organized under a title inspired by Einstein's last paper from the Prague period: "Relativity and Gravitation, 100 Years after Einstein in Prague". The main topics of the conference included: classical relativity, numerical relativity, relativistic astrophysics and cosmology, quantum gravity, experimental aspects of gravitation, and conceptual and historical issues. The conference attracted over 200 scientists from 31 countries, among them a number of leading experts in ...