Semi-classical Electrodynamics
Lestone, John
2016-03-01
Quantum electrodynamics is complex and its associated mathematics can appear overwhelming for those not trained in this field. We describe semi-classical approaches that can be used to obtain a more intuitive physical feel for several QED processes including electro-statics, Compton scattering, pair annihilation, the anomalous magnetic moment, and the Lamb shift, that could be taught easily to undergraduate students. Any physicist who brings their laptop to the talk will be able to build spread sheets in less than 10 minutes to calculate g/2 =1.001160 and a Lamb shift of 1057 MHz.
Semi-classical signal analysis
Laleg-Kirati, Taous-Meriem; Sorine, Michel
2010-01-01
This study introduces a new signal analysis method called SCSA, based on a semi-classical approach. The main idea in the SCSA is to interpret a pulse-shaped signal as a potential of a Schr\\"odinger operator and then to use the discrete spectrum of this operator for the analysis of the signal. We present some numerical examples and the first results obtained with this method on the analysis of arterial blood pressure waveforms.
Semi-classical signal analysis
Laleg-Kirati, Taous-Meriem
2012-09-30
This study introduces a new signal analysis method, based on a semi-classical approach. The main idea in this method is to interpret a pulse-shaped signal as a potential of a Schrödinger operator and then to use the discrete spectrum of this operator for the analysis of the signal. We present some numerical examples and the first results obtained with this method on the analysis of arterial blood pressure waveforms. © 2012 Springer-Verlag London Limited.
Classical, Semi-classical and Quantum Noise
Poor, H; Scully, Marlan
2012-01-01
David Middleton was a towering figure of 20th Century engineering and science and one of the founders of statistical communication theory. During the second World War, the young David Middleton, working with Van Fleck, devised the notion of the matched filter, which is the most basic method used for detecting signals in noise. Over the intervening six decades, the contributions of Middleton have become classics. This collection of essays by leading scientists, engineers and colleagues of David are in his honor and reflect the wide influence that he has had on many fields. Also included is the introduction by Middleton to his forthcoming book, which gives a wonderful view of the field of communication, its history and his own views on the field that he developed over the past 60 years. Focusing on classical noise modeling and applications, Classical, Semi-Classical and Quantum Noise includes coverage of statistical communication theory, non-stationary noise, molecular footprints, noise suppression, Quantum e...
Semi-classical methods in nuclear physics
Brink, David M.
These lecture notes present an introduction to some semi-classical techniques which have applications in nuclear physics. Topics discussed include the WKB method, approaches based on the Feynman path integral, the Gutzwiller trace formula for level density fluctuations and the Thomas-Fermi approximation and the Vlasov equation for many-body problems. There are applications to heavy ion fusion reactions, bremsstrahlung emission in alpha decay and nuclear response functions.
A Semi-classical calculus of correlations
De Verdière, Yves Colin
2011-01-01
The method of passive imaging in seismology has been developped recently in order to image the earth crust from recordings of the seismic noise. This method is founded on the computation of correlations of the seismic noise. In this paper, we give an explicit formula for this correlation in the "semi-classical" regime. In order to do that, we define the power spectrum of a random field as the ensemble average of its Wigner measure, this allows phase-space computations: the pseudo-differential calculus and the ray theory. This way, we get a formula for the correlation of the seismic noise in the semi-classcial regime with a source noise which can be localized and non homogeneous. After that, we show how the use of surface guided waves allows to image the earth crust.
Chen Wen-Xue; Zhang Shu-Lian; Zhang Peng; Zeng Zhao-Li
2012-01-01
In this paper,we propose a semi-classical theory to successfully explain the polarization flipping in a single frequency laser. An experimental setup is built to verify this theory. The observed experimental phenomena are consistent with the theoretical analysis.We perform phase retardation measurements of birefringent components using this experimental system.The results show that the measurement repeatability is 0.12° and the measurement accuracy is 0.22°.
Semi-classical Universe Near Initial Singularity
,
2009-01-01
The properties of the quantum universe on extremely small spacetime scales are studied in the semi-classical approach to the well-defined quantum model. It is shown that near the initial cosmological singularity point quantum gravity effects ~ h exhibit themselves in the form of additional matter source with the negative pressure and the equation of state as for ultrastiff matter. The analytical solution of the equations of theory of gravity, in which matter is represented by the radiation and additional matter source of quantum nature, is found. It is shown that in the stage of the evolution of the universe, when quantum corrections ~ h dominate over the radiation, the geometry of the universe is described by the metric which is conformal to a metric of a unit four-sphere in a five-dimensional Euclidean flat space. In the radiation dominated era the metric is found to be conformal to a unit hyperboloid embedded in a five-dimensional Lorentz-signatured flat space. The origin of the universe can be interpreted...
Self-Consistence of Semi-Classical Gravity
Suen, W M
1992-01-01
Simon argued that the semi-classical theory of gravity, unless with some of its solutions excluded, is unacceptable for reasons of both self-consistency and experiment, and that it has to be replaced by a constrained semi-classical theory. We examined whether the evidence is conclusive.
Semi-classical States in Homogeneous Loop Quantum Cosmology
Tan, H; Ma, Yongge; Tan, Huahai
2006-01-01
Semi-classical states in homogeneous loop quantum cosmology (LQC) are constructed by two different ways. In the first approach, we firstly construct an exponentiated annihilation operator. Then a kind of semi-classical (coherent) state is obtained by solving the eigen-equation of that operator. Moreover, we use these coherent states to analyze the semi-classical limit of the quantum dynamics. It turns out that the Hamiltonian constraint operator employed currently in homogeneous LQC has correct classical limit with respect to the coherent states. In the second approach, the other kind of semi-classical state is derived from the mathematical construction of coherent states for compact Lie groups due to Hall.
Semi-classical beam cooling in an intense laser pulse
Yoffe, Samuel R; Noble, Adam; Jaroszynski, Dino A
2014-01-01
We present a novel technique for studying the evolution of a particle distribution using single particle dynamics such that the distribution can be accurately reconstructed using fewer particles than existing approaches. To demonstrate this, the Landau-Lifshiftz description of radiation reaction is adapted into a semi-classical model, for which the Vlasov equation is intractable. Collision between an energetic electron bunch and high-intensity laser pulses are then compared using the two theories. Reduction in beam cooling is observed for the semi-classical case.
Semi-classical limit of relativistic quantum mechanics
L Kocis
2005-07-01
It is shown that the semi-classical limit of solutions to the Klein–Gordon equation gives the particle probability density that is in direct proportion to the inverse of the particle velocity. It is also shown that in the case of the Dirac equation a different result is obtained.
Semi-Classical Quantization of the Many-Anyon System
Illuminati, F
1993-01-01
We discuss the problem of N anyons in harmonic well, and derive the semi-classical spectrum as an exactly solvable limit of the many-anyon Hamiltonian. The relevance of our result to the solution of the anyon-gas model is discussed.
Semi-Classical Quantization of the Many-Anyon System
Illuminati, Fabrizio
1992-01-01
We discuss the problem of N anyons in harmonic well, and derive the semi-classical spectrum as an exactly solvable limit of the many-anyon Hamiltonian. The relevance of our result to the solution of the anyon-gas model is discussed.
Modified Semi-Classical Methods for Nonlinear Quantum Oscillations Problems
Moncrief, Vincent; Maitra, Rachel
2012-01-01
We develop a modified semi-classical approach to the approximate solution of Schrodinger's equation for certain nonlinear quantum oscillations problems. At lowest order, the Hamilton-Jacobi equation of the conventional semi-classical formalism is replaced by an inverted-potential-vanishing-energy variant thereof. Under smoothness, convexity and coercivity hypotheses on its potential energy function, we prove, using the calculus of variations together with the Banach space implicit function theorem, the existence of a global, smooth `fundamental solution'. Higher order quantum corrections, for ground and excited states, are computed through the integration of associated systems of linear transport equations, and formal expansions for the corresponding energy eigenvalues obtained by imposing smoothness on the quantum corrections to the eigenfunctions. For linear oscillators our expansions naturally truncate, reproducing the well-known solutions for the energy eigenfunctions and eigenvalues. As an application, w...
Coulombic potentials in the semi-classical limit
Chantelau, K. (Technische Univ. Berlin (Germany, F.R.). Fachbereich 3 - Mathematik)
1990-05-01
This paper is devoted to Schroedinger operators in two dimensions with singular (Coulombic) potentials. We investigate the behaviour of the eigenvalues at the bottom of the spectrum in the semi-classical limit. To overcome the difficulties due to the singularities, we use some kind of generalisation of the Levi-Civita transform. After this regularisation, we apply the theory of Helffer and Sjoestrand to get the full asymptotics for the eigenvalues. (orig.).
A Semi-Classical Model to Study Nuclear Fragmentation
Navarro, Martha; Chernomoretz, Ariel; Dorso, Claudio; Lopez, Jorge
1999-10-01
A semi-classical model based on the use of molecular dynamics has been developed for the study of heavy-ion reactions at intermediate energies. The model reproduces nucleon-nucleon cross sections through the use of a two-body potential. The study covers several characteristics of heavy-ion collisions, such as formation of necks, and formation of intermediate residue. Preliminary results on the use of the model to study the caloric curve of nuclear matter and the temperature evolution of the system are also discussed.
Semi-classical quantum theory for cyclotron radiation
陈军锋; 邓劲松; 徐毅; 尤峻汉
1997-01-01
A semi-classical quantum theory of the cyclotron radiation of the nonrelativistic thermal electrons in a very strong magnetic field is presented.The basic formulae of the absorption coefficient of cyclotron resonance kv and the absorption (scattering) cross-section of cyclotron resonance σv have been derived under the quadrupole approximation.σv is an important quantity in the study of the "magnetic inverse-Compton scattering".It is shown that σv is greatly larger than the Thomson cross-sectron σT,which is important in discussing the magnetic inverse-Compton scattering of the relativistic electrons in a very strong magnetic field.
On semi-Classical Questions Related to Signal Analysis
Laleg-Kirati, Taous-Meriem
2010-01-01
This study explores the reconstruction of a signal using spectral quantities associated with some self-adjoint realization of an h-dependent Schr\\"odinger operator when the parameter h tends to 0. Theoretical results in semi-classical analysis are proved. Some numerical results are also presented. We first consider as a toy model the sech^2 function. Then we study a real signal given by arterial blood pressure measurements. This approach seems to be very promising in signal analysis. Indeed it provides new spectral quantities that can give relevant information on some signals as it is the case for arterial blood pressure signal.
A semi-classical treatment of channeling radiation reaction
Huang, Zhirong; Chen, Pisin; Ruth, Ronald D.
1996-10-01
A semi-classical formalism is used to calculate the radiation reaction of a relativistic particle in a straight, continuous focusing system. Due to the absence of quantum excitation in such a focusing system, the radiation damping rate of the transverse action obtained using this formalism agrees exactly with the result from the classical Lorentz-Dirac radiation reaction equation. In the limit where the pitch angle of the particle is much smaller than the radiation opening angle, the transverse action damps exponentially with an energy-independent rate that is much faster than the energy decay rate. In the opposite limit, both the transverse action and the energy damp with power laws and their relative rates are comparable. The general time-dependence of the transverse action damping and the energy decay are obtained analytically from these rate equations.
Semi-classical Scar functions in phase space
Rivas, A M F
2006-01-01
We develop a semi-classical approximation for the scar function in the Weyl-Wigner representation in the neighborhood of a classically unstable periodic orbit of chaotic two dimensional systems. The prediction of hyperbolic fringes, asymptotic to the stable and unstable manifolds, is verified computationally for a (linear) cat map, after the theory is adapted to a discrete phase space appropriate to a quantized torus. Characteristic fringe patterns can be distinguished even for quasi-energies where the fixed point is not Bohr-quantized. Also the patterns are highly localized in the neighborhood of the periodic orbit and along its stable and unstable manifolds without any long distance patterns that appears for the case of the spectral Wigner function.
Improvements on Semi-Classical Distorted-Wave model
Sun Weili; Watanabe, Y.; Kuwata, R. [Kyushu Univ., Fukuoka (Japan); Kohno, M.; Ogata, K.; Kawai, M.
1998-03-01
A method of improving the Semi-Classical Distorted Wave (SCDW) model in terms of the Wigner transform of the one-body density matrix is presented. Finite size effect of atomic nuclei can be taken into account by using the single particle wave functions for harmonic oscillator or Wood-Saxon potential, instead of those based on the local Fermi-gas model which were incorporated into previous SCDW model. We carried out a preliminary SCDW calculation of 160 MeV (p,p`x) reaction on {sup 90}Zr with the Wigner transform of harmonic oscillator wave functions. It is shown that the present calculation of angular distributions increase remarkably at backward angles than the previous ones and the agreement with the experimental data is improved. (author)
Semi-Classical field theory as Decoherence Free Subspaces
Varela, Jaime
2014-01-01
We formulate semi-classical field theory as an approximate decoherence-free-subspace of a finite-dimensional quantum-gravity hilbert space. A complementarity construction can be realized as a unitary transformation which changes the decoherence-free-subspace. This can be translated to signify that field theory on a global slice, in certain space-times, is the simultaneous examination of two different superselected sectors of a gauge theory. We posit that a correct course graining procedure of quantum gravity should be WKB states propagating in a curved background in which particles exiting a horizon have imaginary components to their phases. The field theory appears non-unitary, but it is due to the existence of approximate decoherence free sub-spaces. Furthermore, the importance of operator spaces in the course-graining procedure is discussed. We also briefly touch on Firewalls.
On semi-classical questions related to signal analysis
Helffer, Bernard
2011-12-01
This study explores the reconstruction of a signal using spectral quantities associated with some self-adjoint realization of an h-dependent Schrödinger operator -h2(d2/dx2)-y(x), h>0, when the parameter h tends to 0. Theoretical results in semi-classical analysis are proved. Some numerical results are also presented. We first consider as a toy model the sech2 function. Then we study a real signal given by arterial blood pressure measurements. This approach seems to be very promising in signal analysis. Indeed it provides new spectral quantities that can give relevant information on some signals as it is the case for arterial blood pressure signal. © 2011 - IOS Press and the authors. All rights reserved.
Semi-Classical Wavefunction Perspective to High-Harmonic Generation
Mauger, Francois; Lopata, Kenneth; Schafer, Kenneth J; Gaarde, Mette B
2015-01-01
We introduce a semi-classical wavefunction (SCWF) model for strong-field physics and attosecond science. When applied to high harmonic generation (HHG), this formalism allows one to show that the natural time-domain separation of the contribution of ionization, propagation and recollisions to the HHG process leads to a frequency-domain factorization of the harmonic yield into these same contributions, for any choice of atomic or molecular potential. We first derive the factorization from the natural expression of the dipole signal in the temporal domain by using a reference system, as in the quantitative rescattering (QRS) formalism [J. Phys. B. 43, 122001 (2010)]. Alternatively, we show how the trajectory component of the SCWF can be used to express the factorization, which also allows one to attribute individual contributions to the spectrum to the underlying trajectories.
Minisuperspace Stellar Collapse in Semi-Classical Gravity
Balakrishna, Jayashree; Moran, Christine Corbett
2015-01-01
We compute the Schr\\"odinger and WKB propagators for the semi-classical collapse of a sphere of dust. This extends the work by Redmount and Suen (1993) from the free particle case to nontrivial gravity. In the Oppenheimer-Snyder model, a star can be idealised as a collapsing dust sphere of uniform density and zero pressure. The particles that make up the star have the attributes of classical dust where each particle is assumed to be infinitesimal in size and to interact only gravitationally with other matter. We include quantum mechanical effects, which lift some of these assumptions. This allows for the possibility that some configurations will not collapse to black holes. We find analytic, closed-form solutions for classical paths of a particle on the surface of a collapsing star in Schwarzschild and Kruskal geometries. Kruskal coordinates can be used to study the wavefunction inside the apparent horizon. The propagator is written in closed form in Schwarzschild coordinates in both the WKB and in the Schr\\"...
Semi-classical string solutions for N=1 SYM
Pons, J M; Pons, Josep M.; Talavera, Pere
2003-01-01
We study semi-classically the dynamics of string solitons in the Maldacena-Nunez background, dual in the infra-red to N=1, d=4 SYM. For closed string configurations rotating in the S^2 x R space wrapped by the stack of N D-branes we find a behavior that indicates the decoupling of the stringy Kaluza-Klein modes with sufficiently large SO(3) quantum numbers. We show that the spectrum of a pulsating string configuration in S^2 coincides with that of a N=2 super Sine-Gordon model. Closed string configurations spinning in the transversal S^3 give a relation of the energy and the conserved angular momentum identical to that obtained for configurations spinning in the S^5 of the AdS_5 x S^5, dual to N =4 SYM. In order to obtain non-trivial relations between the energy and the spin, we also consider conical-like configurations stretching along a radial variable in the unwrapped directions of the system of D-branes and simultaneously along the transversal direction. We find that in this precise case, these configurat...
Conformal Blocks Beyond the Semi-Classical Limit
Fitzpatrick, A Liam
2015-01-01
Black hole microstates and their approximate thermodynamic properties can be studied using heavy-light correlation functions in AdS/CFT. Universal features of these correlators can be extracted from the Virasoro conformal blocks in CFT2, which encapsulate quantum gravitational effects in AdS3. At infinite central charge c, the Virasoro vacuum block provides an avatar of the black hole information paradox in the form of periodic Euclidean-time singularities that must be resolved at finite c. We compute Virasoro blocks in the heavy-light, large c limit, extending our previous results by determining perturbative 1/c corrections. We obtain explicit closed-form expressions for both the `semi-classical' $h_L^2 / c^2$ and `quantum' $h_L / c^2$ corrections to the vacuum block, and we provide integral formulas for general Virasoro blocks. We comment on the interpretation of our results for thermodynamics, discussing how monodromies in Euclidean time can arise from AdS calculations using `geodesic Witten diagrams'. We ...
Semi-classical properties of Berezin–Toeplitz operators with C{sup k}-symbol
Barron, Tatyana, E-mail: tatyana.barron@uwo.ca; Pinsonnault, Martin, E-mail: mpinson@uwo.ca [Department of Mathematics, University of Western Ontario, London, Ontario N6A 5B7 (Canada); Ma, Xiaonan, E-mail: ma@math.jussieu.fr [Institut Universitaire de France and Université Paris Diderot–Paris 7, UFR de Mathématiques, Case 7012, 75205 Paris Cedex 13 (France); Marinescu, George, E-mail: gmarines@math.uni-koeln.de [Mathematisches Institut, Universität zu Köln, Weyertal 86-90, 50931 Köln, Germany and Institute of Mathematics “Simion Stoilow,” Romanian Academy, Bucharest (Romania)
2014-04-15
We obtain the semi-classical expansion of the kernels and traces of Toeplitz operators with C{sup k}-symbol on a symplectic manifold. We also give a semi-classical estimate of the distance of a Toeplitz operator to the space of self-adjoint and multiplication operators.
Some semi-classical issues in boundary sine-Gordon model
Kormos, M
2002-01-01
The semi-classical quantisation of the two lowest energy static solutions of boundary sine-Gordon model is considered. A relation between the Lagrangian and bootstrap parameters is established by comparing their quantum corrected energy difference and the exact one. This relation is also confirmed by studying the semi-classical limit of soliton reflections on the boundary.
Classical and semi-classical solutions of the Yang--Mills theory. [Review
Jackiw, R.; Nohl, C.; Rebbi, C.
1977-12-01
This review summarizes what is known at present about classical solutions to Yang-Mills theory both in Euclidean and Minkowski space. The quantal meaning of these solutions is also discussed. Solutions in Euclidean space expose multiple vacua and tunnelling of the quantum theory. Those in Minkowski space-time provide a semi-classical spectrum for a conformal generator.
Globally singularity-free semi-classical wave functions in closed form
Jung, C; Seligman, T H
2000-01-01
We use a factorization technique and representation of canonical transformations to construct globally valid closed form expressions without singularities of semi-classical wave functions for arbitrary smooth potentials over a one-dimensional position space.
Entropy correction of charged black hole via fermions tunneling beyond semi-classical approximation
无
2010-01-01
Motivated by the idea of tunneling beyond semi-classical approximation of Majhi et al., we discuss entropy correction of Dirac particles tunneling from the Reissner-Nordstrm black hole with a global monopole. To get the corrections correctly, we regard the proportionality constants of quantum correction terms to the semi-classical term of action as the inverse of the square of the Planck Length but not that of the Planck Mass. Our study shows that corrections to the Bekenstein-Hawking entropy, namely the logarithmic term and the inverse area term, may be reproduced as the quantum effect is considered.
The symmetric = ω -semi-classical orthogonal polynomials of class one
Maroni, P.; Mejri, M.
2008-12-01
We give the system of Laguerre-Freud equations associated with the = ω -semi-classical functionals of class one, where = ω is the divided difference operator. This system is solved in the symmetric case. There are essentially two canonical cases. The corresponding integral representations are given.
The semi-classical energy of closed Nambu-Goto strings
Zahn, Jochen
2016-01-01
We compute semi-classical corrections to the energy of rotating closed Nambu-Goto strings. We find the Regge intercept $a = 1 + \\frac{D-2}{24}$ for $D$ dimensional target space. Also the discrepancy with the standard approaches to string quantization is clarified.
Adding quantum effects to the semi-classical molecular dynamics simulations
Yang, Siyang
2011-01-01
Simulating the molecular dynamics (MD) using classical or semi-classical trajectories provides important details for the understanding of many chemical reactions, protein folding, drug design, and solvation effects. MD simulations using trajectories have achieved great successes in the computer simulations of various systems, but it is difficult to incorporate quantum effects in a robust way. Therefore, improving quantum wavepacket dynamics and incorporating nonadiabatic transitions and quantum effects into classical and semi-classical molecular dynamics is critical as well as challenging. In this paper, we present a MD scheme in which a new set of equations of motion (EOM) are proposed to effectively propagate nuclear trajectories while conserving quantum mechanical energy which is critical for describing quantum effects like tunneling. The new quantum EOM is tested on a one-state one-dimensional and a two-state two-dimensional model nonadiabatic systems. The global quantum force experienced by each trajecto...
Semi-classical statistical approach to Fr\\"ohlich condensation theory
Preto, Jordane
2012-01-01
Fr\\"ohlich model equations describing phonon condensation in open systems of biological relevance are here reinvestigated in a semi-classical non-equilibrium statistical context (with "semi-classical" it is meant that the evolution of the system is described by means of classical equations with the addition of energy quantization). In particular, the assumptions that are necessary to deduce Fr\\"ohlich rate equations are highlighted and we show how these hypotheses led us to write an appropriate form for the master equation. As a comparison with known previous results, analytical relations with the Wu-Austin quantum Hamiltonian description are emphasized. Finally, we show how solutions of the master equation can be implemented numerically and outline some representative results of the condensation effect. Our approach thus provides more information with respect to the existing ones, in what we are concerned with the time evolution of the probability density functions instead of following average quantities.
Filipuk, Galina; Zhang, Lun
2011-01-01
We show that the coefficients of the three-term recurrence relation for orthogonal polynomials with respect to a semi-classical extension of the Laguerre weight satisfy the fourth Painlev\\'e equation when viewed as functions of one of the parameters in the weight. We compare different approaches to derive this result, namely, the ladder operators approach, the isomonodromy deformations approach and combining the Toda system for the recurrence coefficients with a discrete equation. We also discuss a relation between the recurrence coefficients for the Freud weight and the semi-classical Laguerre weight and show how it arises from the B\\"acklund transformation of the fourth Painlev\\'e equation.
The recurrence coefficients of semi-classical Laguerre polynomials and the fourth Painlevé equation
Filipuk, Galina; Van Assche, Walter; Zhang, Lun
2012-05-01
We show that the coefficients of the three-term recurrence relation for orthogonal polynomials with respect to a semi-classical extension of the Laguerre weight satisfy the fourth Painlevé equation when viewed as functions of one of the parameters in the weight. We compare different approaches to derive this result, namely, the ladder operators approach, the isomonodromy deformations approach and combining the Toda system for the recurrence coefficients with a discrete equation. We also discuss a relation between the recurrence coefficients for the Freud weight and the semi-classical Laguerre weight and show how it arises from the Bäcklund transformation of the fourth Painlevé equation.
High-frequency averaging in semi-classical Hartree-type equations
Giannoulis, Johannes; Sparber, Christof
2009-01-01
We investigate the asymptotic behavior of solutions to semi-classical Schroedinger equations with nonlinearities of Hartree type. For a weakly nonlinear scaling, we show the validity of an asymptotic superposition principle for slowly modulated highly oscillatory pulses. The result is based on a high-frequency averaging effect due to the nonlocal nature of the Hartree potential, which inhibits the creation of new resonant waves. In the proof we make use of the framework of Wiener algebras.
Stochastic semi-classical description of sub-barrier fusion reactions
Ayik Sakir
2011-10-01
Full Text Available A semi-classical method that incorporates the quantum effects of the low-lying vibrational modes is applied to fusion reactions. The quantum effect is simulated by stochastic sampling of initial zero-point ﬂuctuations of the surface modes. In this model, dissipation of the relative energy into non-collective excitations of nuclei can be included straightforwardly. The inclusion of dissipation is shown to increase the agreement with the fusion cross section data of Ni isotopes.
Coupled-channel cavity QED model and Semi-classical solution
WEN Ling-hua; KONG Ling-bo; LIU Min; ZHAN Ming-sheng
2004-01-01
A semi-classical scheme is presented to solve the coupled-channel cavity QED (CQED) model. Such model exhibits remarkable characteristics as shown by numerical calculations. A relation between the swing or angular velocity of the detuning and the motion of the atoms is discussed. With the augmentation of the optical field intensity or frequency, the atoms are trapped firstly and then they move stochastically and finally chaos sets in.
Mathematical properties of a semi-classical signal analysis method: Noisy signal case
Liu, Dayan
2012-08-01
Recently, a new signal analysis method based on a semi-classical approach has been proposed [1]. The main idea in this method is to interpret a signal as a potential of a Schrodinger operator and then to use the discrete spectrum of this operator to analyze the signal. In this paper, we are interested in a mathematical analysis of this method in discrete case considering noisy signals. © 2012 IEEE.
On the semi-classical limit of scalar products of the XXZ spin chain
Jiang, Yunfeng; Brunekreef, Joren
2017-03-01
We study the scalar products between Bethe states in the XXZ spin chain with anisotropy |Δ| > 1 in the semi-classical limit where the length of the spin chain and the number of magnons tend to infinity with their ratio kept finite and fixed. Our method is a natural yet non-trivial generalization of similar methods developed for the XXX spin chain. The final result can be written in a compact form as a contour integral in terms of Faddeev's quantum dilogarithm function, which in the isotropic limit reduces to the classical dilogarithm function.
On the Semi-Classical Limit of Scalar Products of the XXZ Spin Chain
Jiang, Yunfeng
2016-01-01
We study the scalar products between Bethe states in the XXZ spin chain with anisotropy $|\\Delta|>1$ in the semi-classical limit where the length of the spin chain and the number of magnons tend to infinity with their ratio kept finite and fixed. Our method is a natural yet non-trivial generalization of similar methods developed for the XXX spin chain. The final result can be written in a compact form as a contour integral in terms of Faddeev's quantum dilogarithm function, which in the isotropic limit reduces to the classical dilogarithm function.
Solving effective field theory of interacting QCD pomerons in the semi-classical approximation
Bondarenko, S; Bondarenko, Sergey; Motyka, Leszek
2006-01-01
Effective field theory of BFKL pomerons interacting by QCD triple pomeron vertices is investigated. Classical equations of motion for the effective pomeron fields are presented being a minimal extension of the Balitsky-Kovchegov equation that incorporates both merging and splitting of the pomerons and that is self-dual. The equations are solved for symmetric boundary conditions. The solutions provide the dominant contribution to the scattering amplitudes in the semi-classical approximation. We find that for rapidities of the scattering larger than a critical value Y_c at least two classical solutions exist. Curiously, for each of the two classical solutions with the lowest action the symmetry between the projectile and the target is found to be spontaneously broken, being however preserved for the complete set of classical solutions. The solving configurations at rapidities Y>Y_c consist of a Gribov field being strongly suppressed even at very large gluon momenta and the complementary Gribov field that conver...
Big Crunch Avoidance in k = 1 Semi-Classical Loop Quantum Cosmology
Singh, P; Singh, Parampreet; Toporensky, Alexey
2004-01-01
It is well known that a closed universe with a minimally coupled massive scalar field always collapses to a singularity unless the initial conditions are extremely fine tuned. We show that the corrections to the equations of motion for the massive scalar field, given by loop quantum gravity in high curvature regime, always lead to a bounce independently of the initial conditions. In contrast to the previous works in loop quantum cosmology, we note that the singularity can be avoided even at the semi-classical level of effective dynamical equations with non-perturbative quantum gravity modifications, without using a discrete quantum evolution.
Magnus, Alphonse P.
1993-01-01
Recurrence coefficients of semi-classical orthogonal polynomials (orthogonal polynomials related to a weight function $w$ such that $w'/w$ is a rational function) are shown to be solutions of non linear differential equations with respect to a well-chosen parameter, according to principles established by D. G. Chudnovsky. Examples are given. For instance, the recurrence coefficients in $a_{n+1}p_{n+1}(x)=xp_n(x) -a_np_{n-1}(x)$ of the orthogonal polynomials related to the weight $\\exp(-x^4/4-...
Relativistic semi-classical theory of atom ionization in ultra-intense laser
无
2001-01-01
A relativistic semi-classical theory (RSCT) of H-atom ionizationin ultra-intense laser (UIL) is proposed. A relativistic analytical expression for ionization probability of H-atom in its ground state is given. This expression, compared with non-relativistic expression, clearly shows the effects of the magnet vector in the laser, the non-dipole approximation and the relativistic mass-energy relation on the ionization processes. At the same time, we show that under some conditions the relativistic expression reduces to the non-relativistic expression of non-dipole approximation. At last, some possible applications of the relativistic theory are briefly stated.
Semi-classical periodic-orbit theory for chaotic Hamiltonians with discrete symmetries
Seligman, T.H.; Weidenmuller, H.A
1994-12-07
We generalize an idea applied recently to the case of identical particles and present a group-theoretical analysis of the periodic-orbit structure of a chaotic dynamical system with a discrete symmetry. The class structure of the group provides the key for the classification of periodic orbits. This structure perfectly fits the quantum-mechanical trace formula which is the starting point for the Balian-Bloch-Gutzwiller semi-classical approximation. For a specific irreducible representation of the symmetry group, we derive a modified form of the periodic-orbit sum. (author)
Barghouty, A. F.
2014-01-01
Accurate estimates of electroncapture cross sections at energies relevant to the modeling of the transport, acceleration, and interaction of energetic neutral atoms (ENA) in space (approximately few MeV per nucleon) and especially for multi-electron ions must rely on detailed, but computationally expensive, quantum-mechanical description of the collision process. Kuang's semi-classical approach is an elegant and efficient way to arrive at these estimates. Motivated by ENA modeling efforts for apace applications, we shall briefly present this approach along with sample applications and report on current progress.
A New Conformal Theory of Semi-Classical Quantum General Relativity
Suhendro I.
2007-10-01
Full Text Available We consider a new four-dimensional formulation of semi-classical quantum general relativity in which the classical space-time manifold, whose intrinsic geometric properties give rise to the effects of gravitation, is allowed to evolve microscopically by means of a conformal function which is assumed to depend on some quantum mechanical wave function. As a result, the theory presented here produces a unified field theory of gravitation and (microscopic electromagnetism in a somewhat simple, effective manner. In the process, it is seen that electromagnetism is actually an emergent quantum field originating in some kind of stochastic smooth extension (evolution of the gravitational field in the general theory of relativity.
Spectral data de-noising using semi-classical signal analysis: application to localized MRS
Laleg-Kirati, Taous-Meriem
2016-09-05
In this paper, we propose a new post-processing technique called semi-classical signal analysis (SCSA) for MRS data de-noising. Similar to Fourier transformation, SCSA decomposes the input real positive MR spectrum into a set of linear combinations of squared eigenfunctions equivalently represented by localized functions with shape derived from the potential function of the Schrodinger operator. In this manner, the MRS spectral peaks represented as a sum of these \\'shaped like\\' functions are efficiently separated from noise and accurately analyzed. The performance of the method is tested by analyzing simulated and real MRS data. The results obtained demonstrate that the SCSA method is highly efficient in localized MRS data de-noising and allows for an accurate data quantification.
Semi-classical locality for the non-relativistic path integral in configuration space
Gomes, Henrique
2015-01-01
In an accompanying paper, we have put forward an interpretation of quantum mechanics grounded on a non-relativistic Lagrangian 3+1 formalism of a closed Universe, existing on timeless configuration space. However, not much was said there about the role of locality, which was not assumed. In this paper, I describe how subsystems existing in (spatial) regions with fixed boundary conditions can be represented as submanifolds of the complete configuration space. I show that if the action functional can be put in the form of Riemannian distance element, then dynamical independence of the subsystem implies that the respective submanifolds are totally geodesic. When two regions are mutually independent the semi-classical path integral kernel factorizes, showing cluster decomposition. To exemplify these constructions I then construct a specific gravitational system with two propagating physical degrees of freedom and no refoliation-invariance. Finally, considering the path integral in this 3+1 context, I implement an...
Flavour effects in Resonant Leptogenesis from semi-classical and Kadanoff-Baym approaches
Dev, P S Bhupal; Pilaftsis, Apostolos; Teresi, Daniele
2015-01-01
Flavour effects play an important role in the statistical evolution of particle number densities in several particle physics phenomena. We present a fully flavour-covariant formalism for transport phenomena, in order to consistently capture all flavour effects in the system. We explicitly study the scenario of Resonant Leptogenesis (RL), and show that flavour covariance requires one to consider generically off-diagonal number densities, rank-4 rate tensors in flavour space, and non-trivial generalization of the discrete symmetries C, P and T. The flavour-covariant transport equations, obtained in our semi-classical framework, describe the effects of three relevant physical phenomena: coherent heavy-neutrino oscillations, quantum decoherence in the charged-lepton sector, and resonant CP violation due to heavy-neutrino mixing. We show quantitatively that the final asymmetry is enhanced by up to an order of magnitude, for electroweak-scale heavy neutrinos, as compared to that obtained from flavour-diagonal or pa...
Semi-classical Locality for the Non-relativistic Path Integral in Configuration Space
Gomes, Henrique
2017-09-01
In an accompanying paper Gomes (arXiv:1504.02818, 2015), we have put forward an interpretation of quantum mechanics based on a non-relativistic, Lagrangian 3+1 formalism of a closed Universe M, existing on timeless configuration space Q of some field over M. However, not much was said there about the role of locality, which was not assumed. This paper is an attempt to fill that gap. Locality in full can only emerge dynamically, and is not postulated. This new understanding of locality is based solely on the properties of extremal paths in configuration space. I do not demand locality from the start, as it is usually done, but showed conditions under which certain systems exhibit it spontaneously. In this way we recover semi-classical local behavior when regions dynamically decouple from each other, a notion more appropriate for extension into quantum mechanics. The dynamics of a sub-region O within the closed manifold M is independent of its complement, M-O, if the projection of extremal curves on Q onto the space of extremal curves intrinsic to O is a surjective map. This roughly corresponds to e^{i\\hat{H}t}circ prO= prOcirc e^{i\\hat{H}t}, where prO:Q→ Q_O^{partial O} is a linear projection. This criterion for locality can be made approximate—an impossible feat had it been already postulated—and it can be applied for theories which do not have hyperbolic equations of motion, and/or no fixed causal structure. When two regions are mutually independent according to the criterion proposed here, the semi-classical path integral kernel factorizes, showing cluster decomposition which is the ultimate aim of a definition of locality.
Visser, M
1997-01-01
In this note I introduce the notion of the ``reliability horizon'' for semi-classical quantum gravity. This reliability horizon is an attempt to quantify the extent to which we should trust semi-classical quantum gravity, and to get a better handle on just where the Planck regime resides. I point out that the key obstruction to pushing semi-classical quantum gravity into the Planck regime is often the existence of large metric fluctuations, rather than a large back-reaction. There are many situations where the metric fluctuations become large long before the back-reaction is significant. Issues of this type are fundamental to any attempt at proving Hawking's chronology protection conjecture from first principles, since I shall prove that the onset of chronology violation is always hidden behind the reliability horizon.
Projective Loop Quantum Gravity II. Searching for Semi-Classical States
Lanéry, Suzanne
2015-01-01
In [arXiv:1411.3592] an extension of the Ashtekar-Lewandowski (AL) state space of Loop Quantum Gravity was set up with the help a projective formalism introduced by Kijowski [Kijowski 1977; see also: arXiv:1304.6330, arXiv:1411.3590]. The motivation for this work was to achieve a more balanced treatment of the position and momentum variables (aka. holonomies and fluxes). Indeed, states in the AL Hilbert spaces describe discrete quantum excitations on top of a vacuum which is an eigenstate of the flux variables (a `no-geometry' state): in such states, most holonomies are totally spread, making it difficult to approximate a smooth, classical 4-geometry. However, going beyond the AL sector does not fully resolve this difficulty: one uncovers a deeper issue hindering the construction of states semi-classical with respect to a full set of observables. In the present article, we analyze this issue in the case of real-valued holonomies (we will briefly comment on the heuristic implications for other gauge groups, eg...
Semi-classical description of matter wave interferometers and hybrid quantum systems
Schneider, Mathias
2015-02-16
This work considers the semi-classical description of two applications involving cold atoms. This is, on one hand, the behavior of a BOSE-EINSTEIN condensate in hybrid systems, i.e. in contact with a microscopic object (carbon nanotubes, fullerenes, etc.). On the other, the evolution of phase space distributions in matter wave interferometers utilizing ray tracing methods was discussed. For describing condensates in hybrid systems, one can map the GROSS-PITAEVSKII equation, a differential equation in the complex-valued macroscopic wave function, onto a system of two differential equations in density and phase. Neglecting quantum dispersion, one obtains a semiclassical description which is easily modified to incorporate interactions between condensate and microscopical object. In our model, these interactions comprise attractive forces (CASIMIR-POLDER forces) and loss of condensed atoms due to inelastic collisions at the surface of the object. Our model exhibited the excitation of sound waves that are triggered by the object's rapid immersion, and spread across the condensate thereafter. Moreover, local particle loss leads to a shrinking of the bulk condensate. We showed that the total number of condensed particles is decreasing potentially in the beginning (large condensate, strong mean field interaction), while it decays exponentially in the long-time limit (small condensate, mean field inetraction negligible). For representing the physics of matter wave interferometers in phase space, we utilized the WIGNER function. In semi-classical approximation, which again consists in ignoring the quantum dispersion, this representation is subject to the same equation of motion as classical phase space distributions, i.e. the LIOUVILLE equation. This implies that time evolution of theWIGNER function follows a phase space flow that consists of classical trajectories (classical transport). This means, for calculating a time-evolved distribution, one has know the initial
O'Sullivan, Colm
2016-03-01
The role of "semi-classical" (Bohr-Sommerfeld) and "semi-quantum-mechanical" (atomic orbital) models in the context of the teaching of atomic theory is considered. It is suggested that an appropriate treatment of such models can serve as a useful adjunct to quantum mechanical study of atomic systems.
Hounga, C.; Hounkonnou, M. N.; Ronveaux, A.
2006-10-01
In this paper, we give Laguerre-Freud equations for the recurrence coefficients of discrete semi-classical orthogonal polynomials of class two, when the polynomials in the Pearson equation are of the same degree. The case of generalized Charlier polynomials is also presented.
Schmiedt, Hanno; Schlemmer, Stephan; Yurchenko, Sergey N.; Yachmenev, Andrey
2017-01-01
We report a new semi-classical method to compute highly excited rotational energy levels of an asymmetric-top molecule. The method forgoes the idea of a full quantum mechanical treatment of the ro-vibrational motion of the molecule. Instead, it employs a semi-classical Green's function approach to describe the rotational motion, while retaining a quantum mechanical description of the vibrations. Similar approaches have existed for some time, but the method proposed here has two novel features. First, inspired by the path integral method, periodic orbits in the phase space and tunneling paths are naturally obtained by means of molecular symmetry analysis. Second, the rigorous variational method is employed for the first time to describe the molecular vibrations. In addition, we present a new robust approach to generating rotational energy surfaces for vibrationally excited states; this is done in a fully quantum-mechanical, variational manner. The semi-classical approach of the present work is applied to calculating the energies of very highly excited rotational states and it reduces dramatically the computing time as well as the storage and memory requirements when compared to the fullly quantum-mechanical variational approach. Test calculations for excited states of SO2 yield semi-classical energies in very good agreement with the available experimental data and the results of fully quantum-mechanical calculations. PMID:28000807
Holographic Description of 2D Conformal Block in Semi-classical Limit
Chen, Bin; Zhang, Jia-ju
2016-01-01
In this paper, we study the holographic descriptions of the conformal block of heavy operators in two-dimensional large $c$ conformal field theory. We consider the case that the operators are pairwise inserted such that the distance between the operators in a pair is much smaller than the others. In this case, each pair of heavy operators creates a conical defect in the bulk. We propose that the conformal block is dual to the on-shell action of three dimensional geometry with conical defects in the semi-classical limit. We show that the variation of the on-shell action with respect to the conical angle is equal to the length of the corresponding conical defect. We derive this differential relation on the conformal block in the field theory by introducing two extra light operators as both the probe and the perturbation. Our study also suggests that the area law of the holographic R\\'enyi entropy must holds for a large class of states generated by a finite number of heavy operators insertion.
Spin Foam Models for Quantum Gravity and semi-classical limit
Dupuis, Maité
2011-01-01
The spinfoam framework is a proposal for a regularized path integral for quantum gravity. Spinfoams define quantum space-time structures describing the evolution in time of the spin network states for quantum geometry derived from Loop Quantum Gravity (LQG). The construction of this covariant approach is based on the formulation of General Relativity as a topological theory plus the so-called simplicity constraints which introduce local degrees of freedom. The simplicity constraints are essential in turning the non-physical topological theory into 4d gravity. In this PhD manuscript, an original way to impose the simplicity constraints in 4d Euclidean gravity using harmonic oscillators is proposed and new coherent states, solutions of the constraints, are given. Moreover, a consistent spinfoam model for quantum gravity has to be connected to LQG and must have the right semi-classical limit. An explicit map between the spin network states of LQG and the boundary states of spinfoam models is given connecting the...
Thermoelectric properties of fully hydrogenated graphene: Semi-classical Boltzmann theory
Reshak, A. H., E-mail: maalidph@yahoo.co.uk [New Technologies-Research Centre, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia)
2015-06-14
Based on the calculated band structure, the electronic transport coefficients of chair-/boat-like graphane were evaluated by using the semi-classical Boltzmann theory and rigid band model. The maximum value of electrical conductivity for chair (boat)-like graphane of about 1.4 (0.6) × 10{sup 19} (Ωms){sup −1} is achieved at 600 K. The charge carrier concentration and the electrical conductivity linearly increase with increasing the temperature in agreement with the experimental work for graphene. The investigated materials exhibit the highest value of Seebeck coefficient at 300 K. We should emphasize that in the chemical potential between ∓0.125 μ(eV) the investigated materials exhibit minimum value of electronic thermal conductivity, therefore, maximum efficiency. As the temperature increases, the electronic thermal conductivity increases exponentially, in agreement with the experimental data of graphene. We also calculated the power factor of chair-/boat-like graphane at 300 and 600 K as a function of chemical potential between ∓0.25 μ(eV)
Schmiedt, Hanno; Schlemmer, Stephan; Yurchenko, Sergei N.; Yachmenev, Andrey; Jensen, Per
2017-06-01
We report a new semi-classical method to compute highly excited rotational energy levels of an asymmetric-top molecule. The method forgoes the idea of a full quantum mechanical treatment of the ro-vibrational motion of the molecule. Instead, it employs a semi-classical Green's function approach to describe the rotational motion, while retaining a quantum mechanical description of the vibrations. Similar approaches have existed for some time, but the method proposed here has two novel features. First, inspired by the path integral method, periodic orbits in the phase space and tunneling paths are naturally obtained by means of molecular symmetry analysis. Second, the rigorous variational method is employed for the first time to describe the molecular vibrations. In addition, we present a new robust approach to generating rotational energy surfaces for vibrationally excited states; this is done in a fully quantum-mechanical, variational manner. The semi-classical approach of the present work is applied to calculating the energies of very highly excited rotational states and it reduces dramatically the computing time as well as the storage and memory requirements when compared to the fully quantum-mechanical variational approach. Test calculations for excited states of SO_2 yield semi-classical energies in very good agreement with the available experimental data and the results of fully quantum-mechanical calculations. We hope to be able to present at the meeting also semi-classical calculations of transition intensities. See also the open-access paper Phys. Chem. Chem. Phys. 19, 1847-1856 (2017). DOI: 10.1039/C6CP05589C
Semi-Classical Dynamics Studies of the Photodissociation of ICN^{-} and BrCN^{-}
Opoku-Agyeman, Bernice; McCoy, Anne B.
2017-06-01
We present the results of surface hopping studies of the photodissociation of ICN^{-} and BrCN^{-} following UV and visible excitations to states that can dissociate to X^{-} + CN or X^{*} + CN^{-} (X = I or Br). Based on previous quantum dynamics studies carried out on the anions, the electronic states that are accessed by the initial UV or visible excitation were found to be coupled, and both photoproducts were observed in the dissociation process. The calculated branching ratios indicated stronger non-adiabatic interactions between the adiabatic electronic states in BrCN^{-} than in ICN^{-}. In this work, we employ Tully's surface hopping algorithm implemented in classical dynamics simulations to investigate the fragmentation processes of these anions. We calculate the branching ratios and the partitioning of the energies among the various degrees of freedom during the dynamics. The results of the surface hopping algorithm are then compared to the reported quantum dynamics results after which the surface hopping approach can then be applied to investigate the dynamics of argon clusters of the ICN^{-} and BrCN^{-}. In addition to comparison between the quantum and classical dynamics calculations, preliminary results for the semi-classical calculations on the ICN^{-} show that during the dissociation process, some of the anions live longer than others. Once the anions are solvated, we expect the presence of the argon atoms to stabilize the complexes as reported in previous work, resulting in longer lifetimes. Since experimental studies carried out on the solvated anions show the existence of recombined products even for clusters as small as ICN^{-}(Ar) or ICN^{-}(Ar)_2, when the clusters are initially excited with visible or UV radiations, respectively,^{b c} the observations of these long-lived anions provide a step towards understanding the dynamics processes that lead to the recombined products in the clusters. B. Opoku-Agyeman, A. S. Case, J. H. Lehman, W
Barghouty, A. F.
2013-01-01
Accurate estimates of electron-capture cross sections at energies relevant to ENA modeling (approx. few MeV per nucleon) and for multi-electron ions must rely on detailed, but computationally expensive, quantummechanical description of the collision process. Kuang's semi-classical approach is an elegant and efficient way to arrive at these estimates. Motivated by ENA modeling efforts, we shall briefly present this approach along with sample applications and report on current progress.
Jacobs, Verne
2016-05-01
Semi-classical and quantum-field descriptions for the interaction of light with matter are systematically discussed. Applications of interest include resonant pump-probe optical phenomena, such as electromagnetically induced transparency. In the quantum-mechanical description of matter systems, we introduce a general reduced-density-matrix framework. Time-domain (equation-of-motion) and frequency-domain (resolvent-operator) formulations are developed in a unified and self-consistent manner, using a Liouville-space operator representation. In the semi-classical description, the electromagnetic field is described as a classical field satisfying the Maxwell equations. Compact Liouville-space operator expressions are derived for the linear and the general (n'th order) non-linear electromagnetic-response tensors describing moving many-electron systems. The tetradic matrix elements of the Liouville-space self-energy operators are evaluated for environmental collisional and radiative interactions. The quantized-field approach is essential for a fully self-consistent quantum-mechanical description. Work supported by the Office of Naval Research through the Basic Research Program at The Naval Research Laboratory.
Semi-classical noise investigation for sub-40nm metal-oxide-semiconductor field-effect transistors
Spathis, C., E-mail: cspathis@ece.upatras.gr; Birbas, A.; Georgakopoulou, K. [Department of Electrical and Computer Engineering, University of Patras, Patras 26500 (Greece)
2015-08-15
Device white noise levels in short channel Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) dictate the performance and reliability of high-frequency circuits ranging from high-speed microprocessors to Low-Noise Amplifiers (LNAs) and microwave circuits. Recent experimental noise measurements with very short devices demonstrate the existence of suppressed shot noise, contrary to the predictions of classical channel thermal noise models. In this work we show that, as the dimensions continue to shrink, shot noise has to be considered when the channel resistance becomes comparable to the barrier resistance at the source-channel junction. By adopting a semi-classical approach and taking retrospectively into account transport, short-channel and quantum effects, we investigate the partitioning between shot and thermal noise, and formulate a predictive model that describes the noise characteristics of modern devices.
Semi-classical mechanics in phase space: the quantum target of minimal strings
Gomez, Cesar [Instituto de Fisica Teorica CSIC/UAM, C-XVI Universidad Autonoma, E-28049 Madrid (Spain); Montanez, Sergio [Instituto de Fisica Teorica CSIC/UAM, C-XVI Universidad Autonoma, E-28049 Madrid (Spain); Resco, Pedro [Instituto de Fisica Teorica CSIC/UAM, C-XVI Universidad Autonoma, E-28049 Madrid (Spain)
2005-11-15
The target space M{sub p,q} of (p,q) minimal strings is embedded into the phase space of an associated integrable classical mechanical model. This map is derived from the matrix model representation of minimal strings. Quantum effects on the target space are obtained from the semiclassical mechanics in phase space as described by the Wigner function. In the classical limit the target space is a fold catastrophe of the Wigner function that is smoothed out by quantum effects. Double scaling limit is obtained by resolving the singularity of the Wigner function. The quantization rules for backgrounds with ZZ branes are also derived.
Semi-Classical Mechanics in Phase Space: The Quantum Target of Minimal Strings
Gómez, C; Resco, P; Gomez, Cesar; Montanez, Sergio; Resco, Pedro
2005-01-01
The target space $M_{p,q}$ of $(p,q)$ minimal strings is embedded into the phase space of an associated integrable classical mechanical model. This map is derived from the matrix model representation of minimal strings. Quantum effects on the target space are obtained from the semiclassical mechanics in phase space as described by the Wigner function. In the classical limit the target space is a fold catastrophe of the Wigner function that is smoothed out by quantum effects. Double scaling limit is obtained by resolving the singularity of the Wigner function. The quantization rules for backgrounds with ZZ branes are also derived.
Black holes, the Wheeler-DeWitt equation and the semi-classical approximation
Ortiz, M E
1994-01-01
The definition of matter states on spacelike hypersurfaces of a 1+1 dimensional black hole spacetime is considered. Because of small quantum fluctuations in the mass of the black hole, the usual approximation of treating the gravitational field as a classical background on which matter is quantized, breaks down near the black hole horizon. On any hypersurface that captures both infalling matter near the horizon and Hawking radiation, a semiclassical calculation is inconsistent. An estimate of the size of correlations between the matter and gravity states shows that they are so strong that a fluctuation in the black hole mass of order exp[-M/M_{Planck}] produces a macroscopic change in the matter state. (Talk given at the 7th Marcel Grossmann Meeting on work in collaboration with E. Keski-Vakkuri, G. Lifschytz and S. Mathur.)
Propagating modes in a periodic wave guide in the semi-classical limit
Faure, Frederic [LPMMC, Maison des Magisteres Jean Perrin, CNRS, BP 166, Grenoble (France)]. E-mail: frederic.faure@ujf-grenoble.fr
2002-02-15
It is well known that the number of propagating modes in a uniform wave guide is the transverse section divided by the wavelength {lambda} (for a two-dimensional (2D) wave guide). In this paper we study the number of propagating modes N{sub modes} in the limit of small {lambda}, in the case where the section is non-constant but periodic. Using results of a study done by Asch and Knauf (Asch J and Knauf A 1998 Nonlinearity 11 175-200), we show that for small {lambda}, N{sub modes} grows like {mu}{sub b}/{lambda} where {mu}{sub b} is the measure of the ballistic classical trajectories inside the guide. In the case of an ergodic wave guide, where there are no ballistic trajectories but only diffusive trajectories, we show that N{sub modes} grows like {radical}D/{radical}{lambda}where D is the diffusion constant. These results are generalized for any Hamiltonian periodic in one direction, and numerical results with the kicked Harper model are given. N{sub modes} can be related to the Landauer conductance. (author)
Benhassine, B. [Nantes Univ., 44 (France)
1994-01-14
At intermediate energies the heavy ion collisions can be studied within the framework of a semi-classical approach based on the Vlasov-Uehling-Uhlenbeck (VUU) equation. Such an approach reduces the N-body problem to its description in terms of the one-body distribution function and constitutes the basis of several successful simulation models. Our aim in this work is to extend these average approaches to treat fluctuations. Within the framework of a linear approximation, we derived a Fokker-Planck transport equation in the one-body phase space. When it is reduced to its first moments, one recovers the VUU equation for the average dynamics together with the time evolution equation for the correlations. The collective transport coefficients are then obtained by projection on the one-body collective space. Independently, using a projection method introduced by Van Kampen, based on the constants of motion, we deduce the stationary expressions for the covariance matrix in phase space. We extract then, the equilibrium dispersions of one-body observables in a homogeneous case and in a spherical symmetric one. These results are compared with two types of simulation models in a relaxation time approximation. In the first one which is of Lagrangian type, the collective transport coefficients are directly extracted from the simulation and consequently the numerical fluctuations are washed out. The second model, due to its Eulerian character, allows us to make a microscopical comparison. (author) 58 refs.
Louarn, K.; Claveau, Y.; Hapiuk, D.; Fontaine, C.; Arnoult, A.; Taliercio, T.; Licitra, C.; Piquemal, F.; Bounouh, A.; Cavassilas, N.; Almuneau, G.
2017-09-01
The aim of this study is to investigate the impact of multiband corrections on the current density in GaAs tunnel junctions (TJs) calculated with a refined yet simple semi-classical interband tunneling model (SCITM). The non-parabolicity of the considered bands and the spin–orbit effects are considered by using a recently revisited SCITM available in the literature. The model is confronted to experimental results from a series of molecular beam epitaxy grown GaAs TJs and to numerical results obtained with a full quantum model based on the non-equilibrium Green’s function formalism and a 6-band k.p Hamiltonian. We emphasize the importance of considering the non-parabolicity of the conduction band by two different measurements of the energy-dependent electron effective mass in N-doped GaAs. We also propose an innovative method to compute the non-uniform electric field in the TJ for the SCITM simulations, which is of prime importance for a successful operation of the model. We demonstrate that, when considering the multiband corrections and this new computation of the non-uniform electric field, the SCITM succeeds in predicting the electrical characteristics of GaAs TJs, and are also in agreement with the quantum model. Besides the fundamental study of the tunneling phenomenon in TJs, the main benefit of this SCITM is that it can be easily embedded into drift-diffusion software, which are the most widely-used simulation tools for electronic and opto-electronic devices such as multi-junction solar cells, tunnel field-effect transistors, or vertical-cavity surface-emitting lasers.
Barghouty, A. F.
2012-01-01
Accurate estimates of electron-capture cross sections at energies relevant to energetic neutral atom (ENA) modeling (approx few MeV per nucleon) and for multi-electron ions must rely on first-principles approaches and/or detailed quantum-mechanical simulation of the collision process. Kuang's semi-classical approach offers a middle-ground, elegant and efficient way to arrive at these estimates. We shall present a sample application and current progress in applying and extending Kuang's formalism to ENA modeling.
Barghouty, A. F.
2012-01-01
Recent discovery by STEREO A/B of energetic neutral hydrogen is spurring an interest and need for reliable estimates of electron capture cross sections at few MeVs per nucleon as well as for multi-electron ions. Required accuracy in such estimates necessitates detailed and involved quantum-mechanical calculations or expensive numerical simulations. For ENA modeling and similar purposes, a semi-classical approach offers a middle-ground approach. Kuang's semiclassical formalism to calculate electron-capture cross sections for single and multi-electron ions is an elegant and efficient method, but has so far been applied to limited and specific laboratory measurements and at somewhat lower energies. Our goals are to test and extend Kuang s method to all ion-atom and ion-ion collisions relevant to ENA modeling, including multi-electron ions and for K-shell to K-shell transitions.
Sinyakova, T.; Buldyreva, J.
2017-01-01
Theoretical hydrogen-broadening coefficients and associated temperature exponents for 12CH3D (J, K) lines in parallel (ΔK = 0) bands are calculated by a semi-classical approach based on a rigorous consideration of the active molecule as a symmetric top, a model intermolecular potential comprising both short- and long-range interactions, and exact classical trajectories. The leading potential terms are shown to provide a realistic description of line broadening in comparison with scarce measurements available in the literature. The calculations performed for 296, 240 and 190 K are used to extract the line-width temperature-dependence exponents for the typical temperature range of atmospheric interest ∼200-300 K. Detailed P-Q-R-line lists are provided for large intervals of quantum numbers (0 ≤ J ≤ 20, 0 ≤ K ≤ J) requested for remote sensing of planetary atmospheres, in particular those of outer planets and their moons. With negligible vibrational dependence of CH3D line-widths and estimated as negligible their sub-branch dependence, these data can be also employed for perpendicular bands.
Smalley, Joseph S T; Shahin, Shiva; Kanté, Boubacar; Fainman, Yeshaiahu
2015-01-01
We analyze the steady-state transmission of high-momentum (high-$k$) electromagnetic waves through metal-semiconductor multilayer systems with loss and gain in the near-infrared (NIR). Using a semi-classical optical gain model in conjunction with the scattering matrix method (SMM), we study indium gallium arsenide phosphide (InGaAsP) quantum wells as the active semiconductor, in combination with the metals, aluminum-doped zinc oxide (AZO) and silver (Ag). Under moderate external pumping levels, we find that NIR transmission through Ag/InGaAsP systems may be enhanced by several orders of magnitude relative to the unpumped case, over a large angular and frequency bandwidth. Conversely, transmission enhancement through AZO/InGaAsP systems is orders of magnitude smaller, and has a strong frequency dependence. We discuss the relative importance of Purcell enhancement on our results and validate analytical calculations based on the SMM with numerical finite-difference time domain simulations.
SLAH HLALI; NEILA HIZEM; ADEL KALBOUSSI
2017-02-01
In this paper the electrical characteristics of metal–insulator–semiconductor (MIS) and metal–insulator–semiconductor–insulator–metal (MISIM) capacitors with (100)-oriented p-type silicon as a substrate under different high-$k$ gate dielectrics (SiO$_2$, HfO$_2$, La$_2$O$_3$ and TiO$_2$) are investigated in the semi-classical and quantum mechanical models. We review the quantum correction in the inversion layer charge density for p-doped structures. The purpose of this paper is to point out the differences between the semi-classical and quantum mechanical charge descriptions at the insulator–semiconductor interface and the effect of the type of oxide and their position (gate oxide or buried oxide) in our structures. In particular, capacitance–voltage ($C–V$), relative position of the sub-band energies and their wavefunctions are studied to examine qualitatively and quantitatively the electron states and charging mechanisms in our devices. We find that parameters such as threshold voltage and device trans-conductance are enormously sensitive to the proper treatment of quantization effects.
A quantum model of option pricing: When Black-Scholes meets Schrödinger and its semi-classical limit
Contreras, Mauricio; Pellicer, Rely; Villena, Marcelo; Ruiz, Aaron
2010-12-01
The Black-Scholes equation can be interpreted from the point of view of quantum mechanics, as the imaginary time Schrödinger equation of a free particle. When deviations of this state of equilibrium are considered, as a product of some market imperfection, such as: Transaction cost, asymmetric information issues, short-term volatility, extreme discontinuities, or serial correlations; the classical non-arbitrage assumption of the Black-Scholes model is violated, implying a non-risk-free portfolio. From Haven (2002) [1] we know that an arbitrage environment is a necessary condition to embedding the Black-Scholes option pricing model in a more general quantum physics setting. The aim of this paper is to propose a new Black-Scholes-Schrödinger model based on the endogenous arbitrage option pricing formulation introduced by Contreras et al. (2010) [2]. Hence, we derive a more general quantum model of option pricing, that incorporates arbitrage as an external time dependent force, which has an associated potential related to the random dynamic of the underlying asset price. This new resultant model can be interpreted as a Schrödinger equation in imaginary time for a particle of mass 1/σ2 with a wave function in an external field force generated by the arbitrage potential. As pointed out above, this new model can be seen as a more general formulation, where the perfect market equilibrium state postulated by the Black-Scholes model represent a particular case. Finally, since the Schrödinger equation is in place, we can apply semiclassical methods, of common use in theoretical physics, to find an approximate analytical solution of the Black-Scholes equation in the presence of market imperfections, as it is the case of an arbitrage bubble. Here, as a numerical illustration of the potential of this Schrödinger equation analogy, the semiclassical approximation is performed for different arbitrage bubble forms (step, linear and parabolic) and compare with the exact
Semi-classical Electrodynamics: A Short Note
Lestone, John Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-10-05
I have previously claimed the key to understanding the numerical value of the fine structure constant is near-field corrections which terminate integrals at low virtual photon energies, thus obverting an infrared divergence common to many QED calculations. I have since switched to a physics-based calculation of the near-field corrections, instead of the previously used educated guess. The relevant equations are presented here.
W. C. Kreye
2010-01-01
Full Text Available Quantum-mechanical and semi-classical spectral-line shapes are computed at =400, 800, and 1000 K for the line core of the 5802 Å line of the Ar-Perturbed/K-Radiator system. HWHMs ('s are measured from computed full spectral-line shapes. The final-state pseudopotential is for the 721/2 state, and the initial-state potential is for the 423/2,3/2 state. Three high-pressure (P log(—versus—log( curves, corresponding to the non-impact region, intersect a similar set of low-P, impact-region curves at intersections, 0's. Similarly, for two sets of log(—versus—log( curves, which yield intersections, 0's, where is the perturber density. These 0's and 0's separate the two regions and represent the upper limits of the impact regions. A specific validity condition for the impact region is given by the equation ≤0. From an earlier spectroscopic, Fabry-Perot paper, expt=0.021 cm−1 at =400 K and =10 torr. Two theoretical values, theor=0.025 and 0.062 cm−1 corresponding to two different pseudo-potentials, are reported. Two -dependent figures are given, in which the first shows an increase in the impact region with , based on as the basic parameter, and the second which shows a decrease in the impact region with , based on as the basic parameter.
On Semi-classical Degravitation and the Cosmological Constant Problems
Patil, Subodh P
2010-01-01
In this report, we discuss a candidate mechanism through which one might address the various cosmological constant problems. We first observe that the renormalization of gravitational couplings (induced by integrating out various matter fields) manifests non-local modifications to Einstein's equations as quantum corrected equations of motion. That is, at the loop level, matter sources curvature through a gravitational coupling that is a non-local function of the covariant d'Alembertian. If the functional form of the resulting Newton's `constant' is such that it annihilates very long wavelength sources, but reduces to $1/M^2_{pl}$ ($M_{pl}$ being the 4d Planck mass) for all sources with cosmologically observable wavelengths, we would have a complimentary realization of the degravitation paradigm-- a realization through which its non-linear completion and the corresponding modified Bianchi identities are readily understood. We proceed to consider various theories whose coupling to gravity may a priori induce no...
Conformal blocks beyond the semi-classical limit
Fitzpatrick, A. Liam [Department of Physics, Boston University,Boston, MA 02215 (United States); Kaplan, Jared [Department of Physics and Astronomy, Johns Hopkins University,Baltimore, MD 21218 (United States)
2016-05-13
Black hole microstates and their approximate thermodynamic properties can be studied using heavy-light correlation functions in AdS/CFT. Universal features of these correlators can be extracted from the Virasoro conformal blocks in CFT{sub 2}, which encapsulate quantum gravitational effects in AdS{sub 3}. At infinite central charge c, the Virasoro vacuum block provides an avatar of the black hole information paradox in the form of periodic Euclidean-time singularities that must be resolved at finite c. We compute Virasoro blocks in the heavy-light, large c limit, extending our previous results by determining perturbative 1/c corrections. We obtain explicit closed-form expressions for both the ‘semi-classical’ h{sub L}{sup 2}/c{sup 2} and ‘quantum’ h{sub L}/c{sup 2} corrections to the vacuum block, and we provide integral formulas for general Virasoro blocks. We comment on the interpretation of our results for thermodynamics, discussing how monodromies in Euclidean time can arise from AdS calculations using ‘geodesic Witten diagrams’. We expect that only non-perturbative corrections in 1/c can resolve the singularities associated with the information paradox.
Nonlocal formalism for nanoplasmonics: Phenomenological and semi-classical considerations
Mortensen, N. Asger
2013-01-01
The plasmon response of metallic nanostructures is anticipated to exhibit nonlocal dynamics of the electron gas when exploring the true nanoscale. We extend the local-response approximation (based on Ohm's law) to account for a general short-range nonlocal response of the homogeneous electron gas...
Status of semi-classical distorted wave (SCDW) model
Watanabe, Y.; Higashi, H.; Kuwata, R.; Kawai, M. [Kyushu Univ., Fukuoka (Japan); Kohno, M.
1997-05-01
The SCDW model to describe the preequilibrium MSD reaction was extended so as to include the 3-step process. The MSD calculations of {sup 58}Ni(p,p`x) at energies of 65, 120 and 200 MeV and {sup 90}Zr(p,p`x) at 160 MeV were carried out using the extended SCDW model and compared with the experimental data. The calculations with no free parameter showed overall good agreement with the experiment, although underprediction is seen at very small and backward angles. We found that the 2- and 3-step contributions were not so large enough to compensate the difference between the 1-step cross sections and the experimental ones at backward angles. The discrepancies seen at very small and large angles is possibly responsible for the local Fermi-gas model which does not work well in the nuclear surface region. The comparisons of the SCDW calculations with the AMD, QMD and FKK calculations led to an interesting result that the differences in the shape of 1-step angular distributions are remarkable among the models, but the multistep components are rather similar in the shape of angular distributions and the step-wise contribution is not so much different. The in-medium N-N cross sections were calculated in the nonrelativistic Brueckner framework with the Paris potential, and were parametrized as a function of the incident energy and the nuclear density. The SCDW calculation with the in-medium N-N cross sections was not so different from that with the free ones. (J.P.N.)
Semi-classical central charge in topologically massive gravity
Compère, Geoffrey
2008-01-01
It is shown that the warped black holes geometries obtained recently in 0807.3040 admit an algebra of asymptotic symmetries isomorphic to the semi-direct product of a Virasoro algebra and an algebra of currents. The realization of this asymptotic symmetry by canonical charges allows one to find the central charge of the Virasoro algebra. The negative value $c = -\\frac{(5\\hat{\
A Fredholm Determinant for Semi-classical Quantization
Cvitanovic, P; Vattay, G; Rugh, H H; Cvitanovi\\'c, Predrag; Rosenqvist, Per E.; Rugh, Hans Henrik
1993-01-01
We investigate a new type of approximation to quantum determinants, the ``\\qFd", and test numerically the conjecture that for Axiom A hyperbolic flows such determinants have a larger domain of analyticity and better convergence than the \\qS s derived from the \\Gt. The conjecture is supported by numerical investigations of the 3-disk repeller, a normal-form model of a flow, and a model 2-$d$ map.
Semi-Classical Models for Virtual Antiparticle Pairs
Batchelor, David; Zukor, Dorothy (Technical Monitor)
2001-01-01
Virtual particle-antiparticle pairs of massive elementary particle& are predicted in Quantum Field Theory (QFT) to appear from the vacuum and annihilate each other again within their Heisenberg lifetimes h/4mc(exp 2). In this work, semiclassical models of this process - for the cases of massive leptons, quarks, and the massive weak bosons W and Z - are constructed. It is shown that the dynamical lifetime of the particle- antiparticle system in each case equals the Heisenberg lifetime to good approximation, and obeys appropriate quantization conditions on the field fluctuation action. In other words, the dynamical lifetime of the semiclassical model agrees with QED and QCD to good approximation. But the formula for the dynamical lifetime in each model includes the force strength coupling constant (e in the lepton case, alpha(sup s) (q(exp 2)) in the quark cases), while the Heisenberg lifetime formula does not. Observing the agreement of the Heisenberg and dynamical lifetimes, we may derive the QED and QCD coupling constants in terms of h, c, and numerical factors only.
Semi-classical approach to quantum black holes
Spallucci, Euro
2014-01-01
In this Chapter we would like to review a "~phenomenological~" approach taking into account the most fundamental feature of string theory or, more in general, of quantum gravity, whatever its origin, which is the existence of a minimal length in the space-time fabric. This length is generally identified with the Planck length, or the string length, but it could be also much longer down to the TeV region. A simple and effective way to keep track of the effects the minimal length in black hole geometries is to solve the Einstein equations with an energy momentum tensor describing non point-like matter. The immediate consequence is the absence of any curvature singularity. Where textbook solutions of the Einstein equations loose any physical meaning because of infinite tidal forces, we find a de Sitter vacuum core of high, but finite, energy density and pressure. An additional improvement regards the final stage of the black hole evaporation leading to a vanishing Hawking temperature even in the neutral, non-rot...
雷依波; 朱超原; 文振翼; 林聖聖
2012-01-01
New implementation of semi-classical trajectory surface hopping dynamic simulation has been developed and applied to the photoisomerization of cis-and trans-isomers on the gas phase.This method not only uses the exponential model to the modification of the originally analytical non-adiabatic transition probability formula,but also involves the constrained Hamiltonian system into the constrained molecular dynamic simulation.Two-dimensional potential energy surfaces of ground S0 and excited S1 states are constructed analytically fitting to ab initio calculations in terms of torsion angle and one dihedral angle around the central ethylenic C=C bond as variables,and the other internal coordinates are all fixed at configuration of one-bond flip conical intersection.The analytical PESs are quite accurate and the mean absolute error is less than 2.4 kcal·mol-1,and much less than 1.0 kcal·mol-1 around conical intersection region.A straight seam line is found on potential energy surfaces that simply separates the cis-area with the trans-area.The constrained Hamiltonian system is employed to run trajectories in the Cartesian coordinate system and surface hopping in terms of the two internal dihedral angles.Typical trajectories are found in which the torsion angle changes monotonically for both cis-to trans-and trans-to cisisomerizations.This is an exact picture of one-bond flip mechanism of photoisomerization around the conical intersection.Quantum yield for trans-to cis-isomerization is simulated as 60.45% in very good agreement with experimental value 55.0%,while quantum yield for cis-to trans-isomerization is simulated as 42.3% in comparison with experimental value 35.0%.As the S1 energy in local minimum of cis-area is higher than that in trans-area,and thus cis-to trans-isomerization is quite possible to access to another Hula-Twist conical intersection.These simulation results demonstrate that the computed cumulative quantum yield and reaction mechanism are consistent
Outcome Research in Classical Psychodrama.
Kellermann, Peter Felix
1987-01-01
Examines various aspects of psychodrama outcome research and summarizes in tabular form 23 outcome studies published between 1952 and 1985, interpreting them as a whole. Concludes that psychodrama constitutes a valid alternative to other therapeutic approaches, especially in promoting behavior change in adjustment, antisocial, and related…
A semi-classical recipe for wobbly limp noodles in partonic soup
Moerman, R W
2016-01-01
We compute the average squared distance, $s^2(t)$, travelled by a light-flavour off-mass-shell coloured parton in a strongly-coupled $\\mathcal{N}=4$ $SU(N_c)$ super-symmetric Yang Mills plasma using the gauge/string duality. In fact, we derive a closed integral expression for $s^2(t;a)$ in $AdS_3$-Schwarzschild, which interpolates between a heavy quark when $a = 0$ and a light quark when $a = 1$, that we evaluate analytically for small virtualities - labelled $s_\\text{small}^2(t;a)$. For arbitrary virtualities, we show that for asymptotically early times the motion is ballistic, $\\left.s^2(t;a)\\right|_{t\\ll\\beta}\\sim t^2$, while at asymptotically late times the motion is diffusive, $\\left. s^2(t;a) \\right|_{t\\gg\\beta} = s_\\text{small}^2(t;a) \\sim 2D(a) t$, from which we are able to extract the diffusion coefficient $D(a)$. Motivated by the apparent universality of the late time behaviour, we compute $s_{\\text{small}}^2(t;a,d)$ and $D(a,d)$ for an arbitrary $AdS_d$-Schwarzschild geometry. From $D(a,d)$ we then...
A note on the semi-classical approximation in quantum gravity
Lifschytz, G; Ortiz, M; Lifschytz, Gilad; Mathur, Samir D; Ortiz, Miguel
1996-01-01
We re-examine the semiclassical approximation in the canonical formulation of quantum gravity. It is shown that the usual interpretation of a WKB state does not give an adequate semiclassical description of both matter and gravity degrees of freedom. A state for the gravitational field is proposed which has the necessary properties to describe quantum field theory on a background spacetime with small quantum fluctuations. Its connection with WKB states is clarified using a reduced phase space formalism. This state is used to give a qualitative analysis of the effects of geometry fluctuations, which can be related to the breakdown of the semiclassical approximation near a black hole horizon.
Semi-classical treatment of $k$-essence effect on cosmic temperature
Bandyopadhyay, Abhijit; Moulik, Arka
2014-01-01
A phenomenological model is described for Cosmic Microwave Background Radiation (CMBR) evolution with dark energy an essential ingredient in the form of a $k-$essence scalar field. The following features of this evolution can be successfully obtained from this model: (a) the {\\it observed} variation of the rate of change of scale factor $a(t)$, i.e. $\\dot a$, with time and (b) the {\\it observed} value of the epoch when the universe went from a decelerating phase to an accelerated phase. These two features have been matched with graphical transcriptions of SNe Ia data. The model also indicates that the evolution is sensitive to the presence of inhomogeneity and this sensitivity increases as one goes further into the past. Further, the value of the inhomogeneity parameter determines the epoch of switch over to an accelerated phase. A positive value of inhomogeneity parameter leads to switch over at earlier epochs, while a negative value leads to switch over at later epochs. If the value of the inhomogeneity par...
Bund, G W
2004-01-01
The mapping of the Wigner distribution function (WDF) for a given bound-state onto a semiclassical distribution function (SDF) satisfying the Liouville equation introduced previously by us is applied to the ground state of the Morse oscillator. Here we give results showing that the SDF gets closer to the corresponding WDF as the number of levels of the Morse oscillator increases. We find that for a Morse oscillator with one level only, the agreement between the WDF and the mapped SDF is very poor but for a Morse oscillator of ten levels it becomes satisfactory.
A remark on the Dunne-Unsal relation in exact semi-classics
Gahramanov, Ilmar
2015-01-01
Recently, it is realized that non-perturbative instanton effects can be generated to all orders by perturbation theory around a degenerate minima via Dunne-Unsal relation in several quantum mechanical systems. In this work we verify the Dunne-Unsal relation for resonance energy levels of one-dimensional polynomial anharmonic oscillators. We show that the relation is applicable to cubic and quartic anharmonic oscillators which are genus one potentials. However for higher order (higher genus) anharmonic potentials the relation is not satisfied and is subject to a certain extension.
Semi-classical analysis of the inner product of Bethe states
Bettelheim, Eldad
2014-01-01
We study the inner product of two Bethe states, one of which is taken on-shell, in an inhomogeneous XXX chain in the Sutherland limit, where the number of magnons is comparable with the length L of the chain and the magnon rapidities arrange in a small number of macroscopically large Bethe strings. The leading order in the large L limit is known to be expressed through a contour integral of a dilogarithm. Here we derive the subleading term. Our analysis is based on a new contour-integral representation of the inner product in terms of a Fredholm determinant. We give two derivations of the sub-leading term. Besides a direct derivation by solving a Riemann-Hilbert problem, we give a less rigorous, but more intuitive derivation by field-theoretical methods. For that we represent the Fredholm determinant as an expectation value in a Fock space of chiral fermions and then bosonize. We construct a collective field for the bosonized theory, the short wave-length part of which may be evaluated exactly, while the long...
The impact of symmetric modes on intramolecular electron transfer: A semi-classical approach
Coropceanu, Veaceslav; Boldyrev, Sergei I.; Risko, Chad; Brédas, Jean-Luc
2006-07-01
We have generalized the Hush equations developed for the analysis of intervalence charge-transfer bands by including into the model the interaction with symmetric vibrations. Our results indicate that in symmetric class-II systems the maximum of the intervalence charge-transfer band is equal to the reorganization energy λ related to the antisymmetric vibrations as is the case in the conventional Hush model. In contrast, the corresponding transition dipole moment and the activation barrier for thermal electron transfer, in addition to their dependence on λ, also depend on the reorganization energy L related to symmetric vibrational modes. We show that the interaction with symmetric vibrational modes reduces the activation barrier and that the thermal electron-transfer rates derived on the basis of a Hush-type analysis of the optical data are generally underestimated.
Particle on a torus knot: Constrained dynamics and semi-classical quantization in a magnetic field
Das, Praloy; Pramanik, Souvik; Ghosh, Subir
2016-11-01
Kinematics and dynamics of a particle moving on a torus knot poses an interesting problem as a constrained system. In the first part of the paper we have derived the modified symplectic structure or Dirac brackets of the above model in Dirac's Hamiltonian framework, both in toroidal and Cartesian coordinate systems. This algebra has been used to study the dynamics, in particular small fluctuations in motion around a specific torus. The spatial symmetries of the system have also been studied. In the second part of the paper we have considered the quantum theory of a charge moving in a torus knot in the presence of a uniform magnetic field along the axis of the torus in a semiclassical quantization framework. We exploit the Einstein-Brillouin-Keller (EBK) scheme of quantization that is appropriate for multidimensional systems. Embedding of the knot on a specific torus is inherently two dimensional that gives rise to two quantization conditions. This shows that although the system, after imposing the knot condition reduces to a one dimensional system, even then it has manifested non-planar features which shows up again in the study of fractional angular momentum. Finally we compare the results obtained from EBK (multi-dimensional) and Bohr-Sommerfeld (single dimensional) schemes. The energy levels and fractional spin depend on the torus knot parameters that specifies its non-planar features. Interestingly, we show that there can be non-planar corrections to the planar anyon-like fractional spin.
Electro-acoustic behavior of the mitotic spindle: a semi-classical coarse-grained model.
Daniel Havelka
Full Text Available The regulation of chromosome separation during mitosis is not fully understood yet. Microtubules forming mitotic spindles are targets of treatment strategies which are aimed at (i the triggering of the apoptosis or (ii the interruption of uncontrolled cell division. Despite these facts, only few physical models relating to the dynamics of mitotic spindles exist up to now. In this paper, we present the first electromechanical model which enables calculation of the electromagnetic field coupled to acoustic vibrations of the mitotic spindle. This electromagnetic field originates from the electrical polarity of microtubules which form the mitotic spindle. The model is based on the approximation of resonantly vibrating microtubules by a network of oscillating electric dipoles. Our computational results predict the existence of a rapidly changing electric field which is generated by either driven or endogenous vibrations of the mitotic spindle. For certain values of parameters, the intensity of the electric field and its gradient reach values which may exert a not-inconsiderable force on chromosomes which are aligned in the spindle midzone. Our model may describe possible mechanisms of the effects of ultra-short electrical and mechanical pulses on dividing cells--a strategy used in novel methods for cancer treatment.
FAST TRACK COMMUNICATION: Semi-classical central charge in topologically massive gravity
Compère, Geoffrey; Detournay, Stéphane
2009-01-01
It is shown that the warped black hole geometries discussed recently in arXiv:0807.3040 (Anninos et al 2008) admit an algebra of asymptotic symmetries isomorphic to the semi-direct product of a Virasoro algebra and an algebra of currents. The realization of this asymptotic symmetry by canonical charges allows us to find the central charge of the Virasoro algebra. The right-moving central charge c_R = -\\frac{(5\\hat{\
Relativistic semi-classical theory of atom ionization in ultra-intense laser
CHEN; Baozhen
2001-01-01
［1］Schoch, A., Seitliche Versetzung eines total reflektierten strahles bei Utraschallwellen, Acustica, 1952, 2: 17.［2］Neubauer, W. G., Ultrasonic reflection of a bounded beam at Rayleigh and critical angles for a plane liquid-solid interface, J. Appl. Phys., 1973, 44: 48.［3］Ngoc, T. D. K., Mayer, W. G., Numerical integration method for reflected beam profiles near Rayleigh angle, J. Acoust. Soc. Am., 1980, 67, 1149.［4］Nagy, P. B., Cho, K., Focal shift of convergent ultrasonic beams reflected from a liquid-solid interface, J. Acoust. Soc. Am., 1987, 81(4): 835.［5］Bertoni, H. L., Hsue, C. W., Tamir, T., Non-specular reflection of convergent beams from liquid-solid interface, Traitement du Signal, 1985, 2: 201.［6］Zhu Guozhen, Liu Liang, Fu Deyong, Reflected beam displacements of a slightly divergent ultrasonic Gaussian beam on a water-glass interface near Rayleigh angle incidence, Chinese Physics Letters, 1999, 16(11): 819.［7］Bertoni, H. L., Tamir, T., Unified theory of Rayleigh-angle phenomena for acoustic beams onto liquid-solid interface, Appl. Phys., 1973, 2: 157.［8］Zeroug, S., Felsen, L. B., Nonspecular reflection of two- and three-dimensional acoustic beams from fluid-immersed plane-layered elastic structures, J. Acoust. Soc. Am., 1994, 95: 3075.［9］Chimenti, D. E., Zeroug, S. et al., Interaction of acoustic beams with fluid-loaded elastic structures, J. Acoust. Soc. Am., 1994, 95(1): 45.［10］Breazeale, M. A. L., Adler, L., Scott, G. W., Interaction of ultrasonic waves incident at the Rayleigh angle onto a liquid-solid interface, J. Appl. Phys., 1977, 48(2): 530.［11］Ngoc, T. D. K., Mayer, W. G., General description of ultrasonic nonspecular reflection and transmission effects for layered media, IEEE Trans. Sonics Ultrason., 1980, SU-27: 229.［12］Martin, F. D., Breazeale, M. A., J. Acoust. Soc. Am., 1971, 49: 1668.［13］Gunarathne, G. P. P., Szilard, J., A new stroboscope for Schlieren and photoelastic visualization of ultrasound, Ultrasonics, 1983, 7: 188.［14］Brekhovskikh, L. M., Waves in Layered Media, New York: Academic Press, 1980, 111.［15］Zhu Guozhen, Fu Deyong, Negative shift of nonspecularly reflected acoustic pulse at liquid-solid interface, Progress in Physics, 1996, 16(3-4): 377.
Curvature maxima in two-state systems: A semi-classical study
Englman, R.
2007-07-01
In an interacting two (electronic-) state model of molecules with one (effective) nuclear degree of freedom the normalized mean square deviation of the curvature (NMSDC) shows a temperature-maximum. The maximum increases with decrease of the interaction strength, but undergoes a sharp transition to no maximum, when the interaction term vanishes. The NMSDC maximum serves as a geometric hallmark for the underlying potential. The analogous result found by Mazzoni and Casetti [L.N. Mazzoni, L. Casetti, Phys. Rev. Lett. 97 (2006) 218104] for folding proteins can be reproduced by this elementary interacting two state model.
Curvature maxima in two-state systems: A semi-classical study
Englman, R. [Soreq NRC, Yavne 81800 (Israel)]. E-mail: englman@vms.huji.ac.il
2007-07-30
In an interacting two (electronic-) state model of molecules with one (effective) nuclear degree of freedom the normalized mean square deviation of the curvature (NMSDC) shows a temperature-maximum. The maximum increases with decrease of the interaction strength, but undergoes a sharp transition to no maximum, when the interaction term vanishes. The NMSDC maximum serves as a geometric hallmark for the underlying potential. The analogous result found by Mazzoni and Casetti [L.N. Mazzoni, L. Casetti, Phys. Rev. Lett. 97 (2006) 218104] for folding proteins can be reproduced by this elementary interacting two state model.
Semi-classical Dynamics of Superradiant Rayleigh Scattering in a Bose-Einstein Condensate
Müller, J H; Targat, R le; Arlt, J J; Polzik, E S; Hilliard, A J
2016-01-01
Due to its coherence properties and high optical depth, a Bose-Einstein condensate provides an ideal setting to investigate collective atom-light interactions. Superradiant light scattering in a Bose-Einstein condensate is a fascinating example of such an interaction. It is an analogous process to Dicke superradiance, in which an electronically inverted sample decays collectively, leading to the emission of one or more light pulses in a well-defined direction. Through time-resolved measurements of the superradiant light pulses emitted by an end-pumped BEC, we study the close connection of superradiant light scattering with Dicke superradiance. A 1D model of the system yields good agreement with the experimental data and shows that the dynamics results from the structures that build up in the light and matter-wave fields along the BEC. This paves the way for exploiting the atom-photon correlations generated by the superradiance.
Top classic citations in pancreatic cancer research.
Li, Qiang; Jiang, Yuan
2016-11-29
The number of times that articles are cited by is widely used to evaluate the impact of an article or an individual author has on its scientific community. This bibliometric analysis aimed to explore the top classic citations in pancreatic cancer (PC) research. A computerized literature search was conducted using the database, the Science Citation Index Expanded. The top 100 highly cited articles were included and further analyzed. The most cited article had 3,032 citations, with a mean of 626 citations per paper. These highly cited articles were published in 37 journals, led by Cancer Research (15 articles). Of the 100 articles, 40 were observational studies, 36 dealt with basic science, and 14 were randomized controlled trials. These articles came from 11 countries, with the USA contributing 79 articles. Fifty-one institutions produced these 100 citation classics, led by Johns Hopkins University (20 articles). Twenty-seven persons authored two or more of the top-cited articles, led by Kern SE (6) and Yeo CJ (5). This analysis of the top highly cited articles allows for the recognition of major advances in PC research and gives a historic perspective on the progress of this specialty of PC research.
Foundational principles of classical Ayurveda research
Somik Raha
2013-01-01
Full Text Available Double-blind randomized controlled trials (RCTs are viewed as the golden standard of drug research in Western medicine. However, RCTs are far from "golden" in many respects. They are impractical for many therapies, such as for surgeries and complex lifestyle changes. They encourage a one-size-fits-all approach to medical treatment that fails to address the huge diversity among individual patients in terms of their physical and emotional symptoms, social and cultural upbringing, and other factors. Perhaps, more importantly, they do not help doctors make the best medical decisions required to produce optimal patient outcomes. To guide a search for an alternate model of medical research, three principles based on Ayurveda, an ancient and powerful system of health care that has stood the test of time, are presented. These principles, arrived at after mining Ayurvedic epistemology, are: Inductive learning, whole systems thinking, and individually optimized therapy. In honor of the ancient sages or "Rishis," whose voice is used to deliver Ayurvedic knowledge in the ancient texts of Ayurveda, these are referred to as the "Rishi principles." Individually optimized therapy is interpreted using the lens of decision analysis. Common research methodologies are examined for embodiment of these principles.
Foundational principles of classical Ayurveda research.
Raha, Somik
2013-10-01
Double-blind randomized controlled trials (RCTs) are viewed as the golden standard of drug research in Western medicine. However, RCTs are far from "golden" in many respects. They are impractical for many therapies, such as for surgeries and complex lifestyle changes. They encourage a one-size-fits-all approach to medical treatment that fails to address the huge diversity among individual patients in terms of their physical and emotional symptoms, social and cultural upbringing, and other factors. Perhaps, more importantly, they do not help doctors make the best medical decisions required to produce optimal patient outcomes. To guide a search for an alternate model of medical research, three principles based on Ayurveda, an ancient and powerful system of health care that has stood the test of time, are presented. These principles, arrived at after mining Ayurvedic epistemology, are: Inductive learning, whole systems thinking, and individually optimized therapy. In honor of the ancient sages or "Rishis," whose voice is used to deliver Ayurvedic knowledge in the ancient texts of Ayurveda, these are referred to as the "Rishi principles." Common research methodologies are examined for embodiment of these principles.
Teresa D'Aprile
2000-11-01
Full Text Available In this paper we study the existence of concentrated solutions of the nonlinear field equation $$ -h^{2}Delta v+V(xv-h^{p}Delta_{p}v+ W'(v=0,, $$ where $v:{mathbb R}^{N}o{mathbb R}^{N+1}$, $Ngeq 3$, $p>N$, the potential $V$ is positive and radial, and $W$ is an appropriate singular function satisfying a suitable symmetric property. Provided that $h$ is sufficiently small, we are able to find solutions with a certain spherical symmetry which exhibit a concentration behaviour near a circle centered at zero as $ho 0^{+}$. Such solutions are obtained as critical points for the associated energy functional; the proofs of the results are variational and the arguments rely on topological tools. Furthermore a penalization-type method is developed for the identification of the desired solutions.
Y Yousefi
2012-09-01
Full Text Available In this paper, a system with spin S=3/2 with general isotropic nearest neighbor exchange within a mean field approximation possess is discnssed. We derive equations describing non-Heisenberg isotropic model using coherent states of SU(4 group in real parameters and then obtain dispersion equations of spin wave of dipole and quadrupole branches for a small linear excitation from the ground state.
Effect of the choice of the tunnelling path on semi-classical numerical simulations of TFET devices
De Michielis, Luca; Iellina, Matteo; Palestri, Pierpaolo; Ionescu, Adrian M.; Selmi, Luca
2012-05-01
In this work a non-local band-to-band tunnelling model has been successfully implemented into a full-band Monte Carlo simulator and applied to Tunnel-FET devices. No stability or statistical noise problems were encountered in spite of particle weights ranging over many orders of magnitude (due to vastly different generation rates at different positions inside the device and biases) so that Tunnel-FET I-V curves could be traced over the whole on-off range. Different approaches for the choice of the tunnelling path have been compared and relevant differences are observed in both the current levels and the spatial distribution of the generated carriers.
Amour, Laurent; Nourrigat, Jean
2011-01-01
We study the Wick symbol of a solution of the time dependent Hartree Fock equation, under weaker hypotheses than those needed for the Weyl symbol in the first paper with thesame title. With similar, we prove some kind of Ehrenfest theorem for observables that are not pseudo-differential operators.
Bohmian measures and their classical limit
Markowich, Peter
2010-09-01
We consider a class of phase space measures, which naturally arise in the Bohmian interpretation of quantum mechanics. We study the classical limit of these so-called Bohmian measures, in dependence on the scale of oscillations and concentrations of the sequence of wave functions under consideration. The obtained results are consequently compared to those derived via semi-classical Wigner measures. To this end, we shall also give a connection to the theory of Young measures and prove several new results on Wigner measures themselves. Our analysis gives new insight on oscillation and concentration effects in the semi-classical regime. © 2010 Elsevier Inc.
Quantum remnants in the classical limit
Kowalski, A.M., E-mail: kowalski@fisica.unlp.edu.ar [Instituto de Física (IFLP-CCT-Conicet), Universidad Nacional de La Plata, C.C. 727, 1900 La Plata (Argentina); Comision de Investigaciones Científicas (CIC) (Argentina); Plastino, A., E-mail: plastino@fisica.unlp.edu.ar [Instituto de Física (IFLP-CCT-Conicet), Universidad Nacional de La Plata, C.C. 727, 1900 La Plata (Argentina); Argentina' s National Research Council (CONICET) (Argentina); SThAR, EPFL Innovation Park, Lausanne (Switzerland)
2016-09-16
We analyze here the common features of two dynamical regimes: a quantum and a classical one. We deal with a well known semi-classic system in its route towards the classical limit, together with its purely classic counterpart. We wish to ascertain i) whether some quantum remnants can be found in the classical limit and ii) the details of the quantum-classic transition. The so-called mutual information is the appropriate quantifier for this task. Additionally, we study the Bandt–Pompe's symbolic patterns that characterize dynamical time series (representative of the semi-classical system under scrutiny) in their evolution towards the classical limit. - Highlights: • We investigate the classical limit (CL) of a well known semi classical model. • The study is made by reference to the Bandt Pompe symbolic approach. • The number and type of associated symbols changes as one proceeds towards the CL. • We ascertain which symbols pertaining to the quantum zone remain in the CL.
Comment on `Do we have a consistent non-adiabatic quantum-classical mechanics?'
Kisil, Vladimir V.
2009-01-01
We argue with claims of the paper [Agostini F., Caprara S. and Ciccotti G., Europhys. Lett. EPL, 78 (2007) Art. 30001, 6] that the quantum-classic bracket introduced in [arXiv:quant-ph/0506122] produces "artificial coupling" and has "genuinely classical nature". Keywords: p-mechanics, quantum, classic, commutator, Poisson bracket, mixing, coupling, semi-classical
On the Classical String Solutions and String/Field Theory Duality
Aleksandrova, D.; Bozhilov, P.
2003-01-01
We classify almost all classical string configurations, considered in the framework of the semi-classical limit of the string/gauge theory duality. Then, we describe a procedure for obtaining the conserved quantities and the exact classical string solutions in general string theory backgrounds, when the string embedding coordinates depend non-linearly on the worldsheet time parameter.
On the Classical String Solutions and String/Field Theory Duality
Aleksandrova, D.; Bozhilov, P.
2003-01-01
We classify almost all classical string configurations, considered in the framework of the semi-classical limit of the string/gauge theory duality. Then, we describe a procedure for obtaining the conserved quantities and the exact classical string solutions in general string theory backgrounds, when the string embedding coordinates depend non-linearly on the worldsheet time parameter.
Classical and quantum mechanics of a particle on a rotating loop
Kar, S; Kar, Sayan; Khare, Avinash
2000-01-01
The toy model of a particle on a vertical rotating circle in the presence of uniform gravitational/ magnetic fields is explored in detail. After an analysis of the classical mechanics of the problem we then discuss the quantum mechanics from both exact and semi--classical standpoints. Exact solutions of the Schrodinger equation are obtained in some cases by diverse methods. Instantons, bounces are constructed and semi-classical, leading order tunneling amplitudes/decay rates are written down. We also investigate qualitatively the nature of small oscillations about the kink/bounce solutions. Finally, the connections of these toy examples with field theoretic and statistical mechanical models of relevance are pointed out.
Classical limit of quantum gravity in an accelerating universe
Schuller, F P; Schuller, Frederic P.; Wohlfarth, Mattias N.R.
2005-01-01
A one-parameter deformation of Einstein-Hilbert gravity with an inverse curvature term is derived as the classical limit of quantum gravity compatible with an accelerating universe. This result is based on the investigation of semi-classical theories with sectional curvature bounds which are shown not to admit static black holes if otherwise of phenomenological interest. Consequences for classical gravity and the canonical quantization program are briefly discussed.
Lorin, E.; Yang, X.; Antoine, X.
2016-06-01
The paper is devoted to develop efficient domain decomposition methods for the linear Schrödinger equation beyond the semiclassical regime, which does not carry a small enough rescaled Planck constant for asymptotic methods (e.g. geometric optics) to produce a good accuracy, but which is too computationally expensive if direct methods (e.g. finite difference) are applied. This belongs to the category of computing middle-frequency wave propagation, where neither asymptotic nor direct methods can be directly used with both efficiency and accuracy. Motivated by recent works of the authors on absorbing boundary conditions (Antoine et al. (2014) [13] and Yang and Zhang (2014) [43]), we introduce Semiclassical Schwarz Waveform Relaxation methods (SSWR), which are seamless integrations of semiclassical approximation to Schwarz Waveform Relaxation methods. Two versions are proposed respectively based on Herman-Kluk propagation and geometric optics, and we prove the convergence and provide numerical evidence of efficiency and accuracy of these methods.
Guimaraes, F.B.
2002-03-07
In this work we describe neutron and proton induced reaction cross-sections for iron produced by the codes TNG and CEM95 in the 5 to 300 MeV energy range. TNG calculations cover the 5-90 MeV range, while CEM95 covers the 50-300 MeV high energy range. The two codes show some disagreements in the overlap energy range, both among themselves and with the experimental data, which are presently being addressed. The experimental data used are from NNDC and/or from LA150 NSE references. We also describe some developments for combining TNG and CEM95 into a new code called CETNG (Cascade Exciton TNG).
On the classical theory of molecular optical activity
Frolov, Alexei M
2010-01-01
The basic principles of classical and semi-classical theories of molecular optical activity are discussed. These theories are valid for dilute solutions of optically active organic molecules. It is shown that all phenomena known in the classical theory of molecular optical activity can be described with the use of one pseudo-scalar which is a uniform function of the incident light frequency $\\omega$. The relation between optical rotation and circular dichroism is derived from the basic Kramers-Kronig relations. In our discussion of the general theory of molecular optical activity we introduce the tensor of molecular optical activity. It is shown that to evaluate the optical rotation and circular dichroism at arbitrary frequencies one needs to know only nine (3 + 6) molecular tensors. The quantum (or semi-classical) theory of molecular optical activity is also briefly discussed. We also raise the possibility of measuring the optical rotation and circular dichroism at wavelengths which correspond to the vacuum ...
Boys in white: a classic of qualitative research turns 50.
Nunes, Everardo Duarte; de Barros, Nelson Filice
2014-01-01
This article analyzes Boys in white: student culture in medical schoolby Howard S. Becker, Blanche Geer, Everett C. Hughes and Anselm Strauss, considered a model of qualitative research in sociology. The analysis investigates the trajectories of the authors, the book, qualitative analysis, and the medical students, emphasizing their importance in the origins of medical sociology and the sociology of medical education. In the trajectory of the authors, bibliographical information is given. The trajectory of qualitative research focuses on how this methodology influences the construction of the field. The investigation of the students' trajectory shows how they progress through their first years at medical school to build their own student culture.
Classical limit of quantum gravity in an accelerating universe
Schuller, Frederic P. [Perimeter Institute for Theoretical Physics, 31 Caroline Street N, Waterloo N2L 2Y5 (Canada)]. E-mail: fschuller@perimeterinstitute.ca; Wohlfarth, Mattias N.R. [II. Institut fuer Theoretische Physik, Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany)]. E-mail: mattias.wohlfarth@desy.de
2005-04-21
A one-parameter deformation of Einstein-Hilbert gravity with an inverse Riemann curvature term is derived as the classical limit of quantum gravity compatible with an accelerating universe. This result is based on the investigation of semi-classical theories with sectional curvature bounds which are shown not to admit static spherically symmetric black holes if otherwise of phenomenological interest. We discuss the impact on the canonical quantization of gravity, and observe that worldsheet string theory is not affected.
Classical and Molecular Genetic Research on General Cognitive Ability.
McGue, Matt; Gottesman, Irving I
2015-01-01
Arguably, no psychological variable has received more attention from behavioral geneticists than what has been called "general cognitive ability" (as well as "general intelligence" or "g"), and for good reason. GCA has a rich correlational network, implying that it may play an important role in multiple domains of functioning. GCA is highly correlated with various indicators of educational attainment, yet its predictive utility is not limited to academic achievement. It is also correlated with work performance, navigating the complexities of everyday life, the absence of various social pathologies (such as criminal convictions), and even health and mortality. Although the causal basis for these associations is not always known, it is nonetheless the case that research on GCA has the potential to provide insights into the origins of a wide range of important social outcomes. In this essay, our discussion of why GCA is considered a fundamentally important dimension of behavior on which humans differ is followed by a look at behavioral genetics research on CGA. We summarize behavioral genetics research that has sought to identify and quantify the total contributions of genetic and environmental factors to individual differences in GCA as well as molecular genetic research that has sought to identify genetic variants that underlie inherited effects. © 2015 The Hastings Center.
Top 100 Cited Classic Articles in Breast Cancer Research.
Uysal, Erdal
2017-07-01
This study aimed to analyze 100 most cited articles in breast cancer research. The data in this study were obtained by a search conducted on the Web of Science (WOS). In brief, the term "breast cancer" was typed in the search box of WOS basic research including all the years and the data. The analysis was carried out by compiling the top 100 cited articles in the shortlist as sorted by the journals, categories of the studies, the countries, the centers, the authors and the publication date. No statistical methods were used in the study. All data were reported as percentages, numbers and bar charts on tables. Our findings showed that the most frequently cited article received 7609 citations to date. Most articles were published in the New England Journal of Medicine. 81% of the studies originated from the USA. The National Institutes of Health (NIH USA) was ranked the first with 21% and it was followed by Harvard University in terms of number of published articles. 42% of the articles were published under the category of medicine and general internal medicine. Top 100 most cited articles originated from the United States. The highest number of articles among the top 100 articles were published in New England Journal of Medicine and National Institutes of Health NIH USA was the leading institutes published the most articles.
Classical integrability for three-point functions: cognate structure at weak and strong couplings
Kazama, Yoichi [Research Center for Mathematical Physics, Rikkyo University,Toshima-ku, Tokyo 171-8501 (Japan); Quantum Hadron Physics Laboratory, RIKEN Nishina Center, Wako 351-0198 (Japan); Institute of Physics, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Komatsu, Shota [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, Ontario, N2L 2Y5 (Canada); Nishimura, Takuya [Institute of Physics, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)
2016-10-10
In this paper, we develop a new method of computing three-point functions in the SU(2) sector of the N=4 super Yang-Mills theory in the semi-classical regime at weak coupling, which closely parallels the strong coupling analysis. The structure threading two disparate regimes is the so-called monodromy relation, an identity connecting the three-point functions with and without the insertion of the monodromy matrix. We shall show that this relation can be put to use directly for the semi-classical regime, where the dynamics is governed by the classical Landau-Lifshitz sigma model. Specifically, it reduces the problem to a set of functional equations, which can be solved once the analyticity in the spectral parameter space is specified. To determine the analyticity, we develop a new universal logic applicable at both weak and strong couplings. As a result, compact semi-classical formulas are obtained for a general class of three-point functions at weak coupling including the ones whose semi-classical behaviors were not known before. In addition, the new analyticity argument applied to the strong coupling analysis leads to a modification of the integration contour, producing the results consistent with the recent hexagon bootstrap approach. This modification also makes the Frolov-Tseytlin limit perfectly agree with the weak coupling form.
Classical Integrability for Three-point Functions: Cognate Structure at Weak and Strong Couplings
Kazama, Y; Nishimura, T
2016-01-01
In this paper, we develop a new method of computing three-point functions in the SU(2) sector of the $\\mathcal{N}=4$ super Yang-Mills theory in the semi-classical regime at weak coupling, which closely parallels the strong coupling analysis. The structure threading two disparate regimes is the so-called monodromy relation, an identity connecting the three-point functions with and without the insertion of the monodromy matrix. We shall show that this relation can be put to use directly for the semi-classical regime, where the dynamics is governed by the classical Landau-Lifshitz sigma model. Specifically, it reduces the problem to a set of functional equations, which can be solved once the analyticity in the spectral parameter space is specified. To determine the analyticity, we develop a new universal logic applicable at both weak and strong couplings. As a result, compact semi-classical formulas are obtained for a general class of three-point functions at weak coupling including the ones whose semi-classical...
Verlegh, P.; Voorveld, H.; Eisend, M.
2016-01-01
This book provides insights into the inspiring and multifaceted field of advertising research, which is confronted with challenges regarding ad content and execution, media placement, as well as online and social media. Distinguishing between digital, classic, subtle, and alternative advertising for
A century of research on the classical locality of Tegelen (province of Limburg, The Netherlands)
Hoek Ostende, van den L.W.; Vos, de J.
2006-01-01
In 1904 Eugène Dubois published the first report on fossil mammals from the vicinity of Tegelen. After a century of research the clay-pits from the area are known as a classical locality for Villafranchian mammals. Antje Schreuder's work was particularly important for making the fossils from Tegelen
Classical Natural History: the importance of volunteers in collection management and research
Reumer, J.W.F.; Post, K.
2010-01-01
As a result of increasing budget constraints and decreasing interest in classical natural history, the work effort of volunteer researchers and the need for private funding are of growing importance. A brief historical background is provided, showing the decreasing interest in the subject shown by g
A century of research on the classical locality of Tegelen (province of Limburg, The Netherlands)
Hoek Ostende, van den L.W.; Vos, de J.
2006-01-01
In 1904 Eugène Dubois published the first report on fossil mammals from the vicinity of Tegelen. After a century of research the clay-pits from the area are known as a classical locality for Villafranchian mammals. Antje Schreuder's work was particularly important for making the fossils from Tegelen
Advances in advertising research (vol. VI): the digital, the classic, the subtle and the alternative
Verlegh, P.; Voorveld, H.; Eisend, M.
2016-01-01
This book provides insights into the inspiring and multifaceted field of advertising research, which is confronted with challenges regarding ad content and execution, media placement, as well as online and social media. Distinguishing between digital, classic, subtle, and alternative advertising for
Intuitionistic Choice and Restricted Classical Logic
Kohlenbach, Ulrich
2001-01-01
theoretic strength of such systems can be determined by functional interpretation based on a non-constructive -operator and his well-known results on the strength of this operator from the 70's. In this note we consider a weaker form LNOS (lesser numerical omniscience schema) of NOS which suffices to derive...... the strong form of binary König's lemma studied by Coquand/Palmgren and gives rise to a new and mathematically strong semi-classical system which, nevertheless, can proof theoretically be reduced to primitive recursive arithmetic PRA. The proof of this fact relies on functional interpretation...
Lee, Sang-Bong
1993-09-01
Quantum manifestation of classical chaos has been one of the extensively studied subjects for more than a decade. Yet clear understanding of its nature still remains to be an open question partly due to the lack of a canonical definition of quantum chaos. The classical definition seems to be unsuitable in quantum mechanics partly because of the Heisenberg quantum uncertainty. In this regard, quantum chaos is somewhat misleading and needs to be clarified at the very fundamental level of physics. Since it is well known that quantum mechanics is more fundamental than classical mechanics, the quantum description of classically chaotic nature should be attainable in the limit of large quantum numbers. The focus of my research, therefore, lies on the correspondence principle for classically chaotic systems. The chaotic damped driven pendulum is mainly studied numerically using the split operator method that solves the time-dependent Schroedinger equation. For classically dissipative chaotic systems in which (multi)fractal strange attractors often emerge, several quantum dissipative mechanisms are also considered. For instance, Hoover`s and Kubo-Fox-Keizer`s approaches are studied with some computational analyses. But the notion of complex energy with non-Hermiticity is extensively applied. Moreover, the Wigner and Husimi distribution functions are examined with an equivalent classical distribution in phase-space, and dynamical properties of the wave packet in configuration and momentum spaces are also explored. The results indicate that quantum dynamics embraces classical dynamics although the classicalquantum correspondence fails to be observed in the classically chaotic regime. Even in the semi-classical limits, classically chaotic phenomena would eventually be suppressed by the quantum uncertainty.
Excursions in classical analysis pathways to advanced problem solving and undergraduate research
Chen, Hongwei
2010-01-01
Excursions in Classical Analysis introduces undergraduate students to advanced problem solving and undergraduate research in two ways. Firstly, it provides a colourful tour of classical analysis which places a wide variety of problems in their historical context. Secondly, it helps students gain an understanding of mathematical discovery and proof. In demonstrating a variety of possible solutions to the same sample exercise, the reader will come to see how the connections between apparently inapplicable areas of mathematics can be exploited in problem-solving. This book will serve as excellent preparation for participation in mathematics competitions, as a valuable resource for undergraduate mathematics reading courses and seminars and as a supplement text in a course on analysis. It can also be used in independent study, since the chapters are free-standing.
Linking contemporary research to the classics: Celebrating 125 years at APA.
Enns, James T; Becker, Stefanie I; Brockmole, James; Castelhano, Monica; Creem-Regehr, Sarah; Gray, Rob; Hecht, Heiko; Juhasz, Barbara; Philbeck, John; Woodman, Geoffrey
2017-10-01
APA is celebrating 125 years this year and at the journal we are commemorating this milestone with a special issue. The inspiration came from our editorial team, who wished to acknowledge the links between game-changing articles that have influenced our research community in the past-we call them classics for short-and contemporary works. The main idea was to feature the work of nine contemporary research teams, while at the same time drawing readers' attention to their links with the classics. In this introduction, we have organized the articles according to several broad themes: active perception, perception for action, action alters perception, perception of our bodies in action, and acting on selective perceptions. As all who have read and contributed to the journal over the past few years have come to realize, it is no longer possible to study perception without considering its role in action. Nor is it possible to study action (formerly called performance, as reflected in the journal title) without understanding the perceptual contributions to action. These nine articles each exemplify, in their own way, how these dynamic interactions play out in contemporary research in our field. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Trends in Psychotherapy Process Research: Samples, Measures, Researchers, and Classic Publications.
Hill, Clara E.; And Others
1994-01-01
Examined psychotherapy studies published in "Journal of Counseling Psychology" (JCP) and "Journal of Consulting and Clinical Psychology" (JCCP) between 1978 and 1992. Found that JCP published mostly process, outcome, and analogue research, whereas JCCP published mostly outcome research. Most process and process-outcome studies across journals were…
Torrielli, Alessandro
2016-08-01
We review some essential aspects of classically integrable systems. The detailed outline of the sections consists of: 1. Introduction and motivation, with historical remarks; 2. Liouville theorem and action-angle variables, with examples (harmonic oscillator, Kepler problem); 3. Algebraic tools: Lax pairs, monodromy and transfer matrices, classical r-matrices and exchange relations, non-ultralocal Poisson brackets, with examples (non-linear Schrödinger model, principal chiral field); 4. Features of classical r-matrices: Belavin-Drinfeld theorems, analyticity properties, and lift of the classical structures to quantum groups; 5. Classical inverse scattering method to solve integrable differential equations: soliton solutions, spectral properties and the Gel’fand-Levitan-Marchenko equation, with examples (KdV equation, Sine-Gordon model). Prepared for the Durham Young Researchers Integrability School, organised by the GATIS network. This is part of a collection of lecture notes.
Citation Classics in "Suicide and Life Threatening Behavior": A Research Note
Stack, Steven
2012-01-01
The number of citations a scholarly work receives is a common measure of its impact on the scientific literature; "citation classics" are the most highly cited works. The content of "Suicide and Life-Threatening Behavior" ("SLTB") citation classics is described here. The impact of "SLTB" citation classics is compared to their counterparts in…
The fuzzy buzz word: conceptualisations of disability in disability research classics.
Grönvik, Lars
2007-07-01
The article analyses five classical texts from the field of disability research/studies. The focus of the analysis is on how disability is defined both on a theoretical level and on an empirical or applied level. The findings suggest that definitional clarity can be questioned. First, a 'traditional' problem of validity occurs in some of the texts. Secondly, lack of clearly expressed and explicit definitions makes it difficult for the reader to understand what the author means with the term disability. Thirdly, some authors alter the definition of disability through their texts, without any explanations, making it arduous for the reader to follow the use and meaning of the term. It is suggested that these problems stem from the lack of proper theorising within the field of disability research. Disability researchers have been focusing on defining separate concepts, without any ambitions to relate them to each other in a theoretical frame. This means that the field of disability research consists of free-floating concepts, poorly related to each other.
Review of Digital Research in the Study of Classical Antiquity [Book
Adam Rabinowitz
2011-07-01
Full Text Available It is often stated that trying to deal with information on the internet is like drinking from a firehose. But trying to put together a book about the current state of digital anything must be rather more like trying to paint a landscape from the window of a moving train. By the time the painting is complete, the scenery has changed dramatically. This puts books on digital approaches to academic disciplines in an interesting position: by the time a volume makes it into the hands of its readers, it is already a historical document as well as a scholarly work. The editors of Digital Research in the Study of Classical Antiquity are very aware of this: as they state, the book seeks "to create a snapshot of the research activities of Digital Classicist members as represented by a selection of the papers given at our Summer seminars and conference panels in one particular year, 2007" (p10. When one considers that the printed volume went to press in 2010, and is being reviewed in 2011, this means that almost four years—a digital eternity—have passed since most of the papers were first composed. I think, therefore, it will be most useful to discuss Digital Research from two perspectives: first, in terms of its scholarly contribution, and second, in terms of what the framing of this work and the identity of its contributors tell us about a particular moment in the history of the field of 'digital humanities'.
Non-classical neutron beams for fundamental and solid state research
H Rauch
2008-10-01
The curious dual nature of the neutron, sometimes a particle, sometimes a wave, is wonderfully manifested in the various non-local interference and quantum contextuality effects observed in neutron interferometry. Non-classical states may become useful for novel fundamental and solid state research. Here we discuss unavoidable quantum losses as they appear in neutron phase-echo and spin rotation experiments and we show how entanglement effects in a single particle system demonstrate quantum contextuality. In all cases of interactions, parasitic beams are produced which cannot be recombined completely with the original beam. This means that a complete reconstruction of the original state would, in principle, be impossible which causes a kind of intrinsic irreversibility. Even small interaction potentials can have huge effects when they are applied in quantum Zeno-like experiments. Recently, it has been shown that an entanglement between external and internal degrees of freedom exists even in single particle systems. This contextuality phenomenon also shows that a quantum system carries much more information than usually extracted. The path towards advanced neutron quantum optics will be discussed.
NATO Advanced Research Workshop on Squeezed and Non-classical Light
Pike, E; Squeezed and Non-classical Light
1988-01-01
The recent generation in the laboratory of phase squeezed and intensity squeezed light beams has brought to fruition the theoretical predictions of such non-classical phenomena which have been made and developed in recent years by a number of workers in the field of quantum optics. A vigorous development is now underway of both theory and experiment and the first measurements have been coi:Jfirmed and extended already in some half dozen laboratories. Although the fields of application of these novellight sources are as yet somewhat hazy in our minds and some inspired thinking is required along these lines, the pace and excitement of the research is very clear. It is to he hoped that the new possibilities of: making measurements below the quantum shot noise lirnit which is made possible by these squeezed states of light willlead to further fundamental advances in the near future. In this NATO ARW a number of the leaders in the field met in the extremely pleasant surroundings of Cortina d'Ampezzo and th...
Bogenschutz, Michael P
2013-03-01
Recent developments in the study of classic hallucinogens, combined with a re-appraisal of the older literature, have led to a renewal of interest in possible therapeutic applications for these drugs, notably their application in the treatment of addictions. This article will first provide a brief review of the research literature providing direct and indirect support for the possible therapeutic effects of classic hallucinogens such as psilocybin and lysergic acid diethylamide (LSD) in the treatment of addictions. Having provided a rationale for clinical investigation in this area, we discuss design issues in clinical trials using classic hallucinogens, some of which are unique to this class of drug. We then discuss the current status of this field of research and design considerations in future randomized trials.
Teaching Statistics Using Classic Psychology Research: An Activities-Based Approach
Holmes, Karen Y.; Dodd, Brett A.
2012-01-01
In this article, we discuss a collection of active learning activities derived from classic psychology studies that illustrate the appropriate use of descriptive and inferential statistics. (Contains 2 tables.)
Information flow during the quantum-classical transition
Kowalski, A.M., E-mail: kowalski@fisica.unlp.edu.a [Instituto de Fisica (IFLP-CCT-Conicet), Fac. de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 727, 1900 La Plata (Argentina)] [Comision de Investigaciones Cientificas (CIC) (Argentina); Martin, M.T., E-mail: mtmartin@fisica.unlp.edu.a [Instituto de Fisica (IFLP-CCT-Conicet), Fac. de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 727, 1900 La Plata (Argentina)] [Argentina' s National Research Council (CONICET) (Argentina); Plastino, A., E-mail: plastino@fisica.unlp.edu.a [Instituto de Fisica (IFLP-CCT-Conicet), Fac. de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 727, 1900 La Plata (Argentina)] [Argentina' s National Research Council (CONICET) (Argentina); Zunino, L., E-mail: lucianoz@ciop.unlp.edu.a [Instituto de Fisica Interdisciplinar y Sistemas Complejos (IFISC) CSIC-UIB, Campus Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain)] [Centro de Investigaciones Opticas (CONICET La Plata - CIC), C.C. 3, 1897 Gonnet (Argentina)] [Departamento de Ciencias Basicas, Facultad de Ingenieria, Universidad Nacional de La Plata (UNLP), 1900 La Plata (Argentina)
2010-04-12
We have exhaustively investigated the classical limit of the semi-classical evolution with reference to a well-known model that represents the interaction between matter and a given field. In this Letter we approach this issue by recourse to a new statistical quantifier called the 'symbolic transfer entropy' [T. Schreiber, Phys. Rev. Lett. 85 (2000) 461; M. Staniek, K. Lehnertz, Phys. Rev. Lett. 100 (2008) 158101]. We encounter that the quantum-classical transition gets thereby described as the sign reversal of the dominating direction of the information flow between classical and quantal variables. This can be considered as an evidence of the physical useful of this new statistical quantifier.
无
2000-01-01
The research on morphology of mineral crystals in China includes classical goniometry of 100 minerals such as hsianghualite, orthobrannerite, jamesonite and bertrandite and surface microtopography of 20 minerals such as wolframite and diamond, among which 5 new minerals and 34 uranium minerals were discovered and measured by Chinese mineralogists. These have enriched mineralogy and crystal morphology and strengthened the study of information of morphological genesis.
Research on Post-classical Narrative Focalization in The Love Wife
郭丽莉
2013-01-01
The Love Wife is considered to be a breakthrough of Gish Jen either in theme and narrative techniques. While, as the critical distinguished narrative technique from the perspective of Post-classical Narratology, the infinitive internal focalization will be analyzed in this paper so as to investigate the five protagonists’search for their own identity and eagerness to achieve the ac-knowledge both from their family and the whole society. Furthermore, the author ’s own view in breaking up the barrier and dis-crimination around the world is also well-illustrated.
Liubarskiĭ, G Iu
2006-01-01
The sequence of classic paradigms in taxonomy that partly replaced each other and partly co-exist is given as follows: the theory of "organ and organism similarity", the naturalistic theory, the descriptive theory, and the phylogenetic theory. The naturalistic classics accepted the notion of "the plan of creation". The rejection of appealing to this plan brought forth certain problems in the formulation of the purpose of taxonomy; these problems were differently solved by the descriptive and the phylogenetic classic traditions. The difficulties of the current paradigms arising from the loss of a "strong purpose", a problem to be solved by taxonomists that is to be clear and interesting to a wide range of non-professionals. The paradox of formalization led to the losing of content of the methods due to their formalization. To attract attention to taxonomy, a new "image of the results" of its work that would be interesting to the non-professionals is necessary. The co-existence of different methods of reseach applied to different groups of facts leads to the loss of integrity of the research. It is not only that the taxon becomes a hypothesis and such hypotheses multiply. The comparison of these hypotheses is problematic, because each of them is supported by its own independent scope of facts. Because of the existence of a fundamental meronotaxonomic discrepancy, taxonomic systems based on different groups of characters appear to be incomparable, being rather systems of characters than systems of taxa. Systems of characters are not directly comparable with each other; they can be compared only through appealing to taxa, but taxa themselves exist only in the form of a number of hypotheses. Consequently, each separate taxonomic approach creates its own nature, its own subject of research. Therefore, it is necessary to describe the subject of research correctly (and indicate the purpose of research), as well as to distinguish clearly between results achieved through
Research of Nasosinusitis in Internal Classic and Treaties of Cold-Attack%鼻渊溯源
徐秋玲; 刘涛
2011-01-01
时代,人们认为变应性鼻炎与肺、肾、胆、手足阳明经、足太阳膀胱经关系密切,为其后的治疗奠定了坚实的理论基础.认为鼻塞、鼻鸣、鼻干等症状与太阳经病、阳明经病及寒湿之邪有关,并提出相应治法,为变应性鼻炎的治疗提供可靠依据.%People in the period of Internal Classic had known the there were a close relation between nasosinusitis and lung, kidney, gallbladder, hand and foot Yang Ming meridian and foot Tai Yang bladder meridian, which built a theory base for the therapy of allergic rhitinis. Treaties of Cold-Attack thought the syndromes of nasal obstruction and dryness were related to Tai Yang meridian disease, Yang Ming meridian disease and the evil of cold and dampness, and brought out the responding therapy methods, which provided depending proof for the therapy of allergic rhitinis.
A model for explaining fusion suppression using classical trajectory method
Phookan, C. K.; Kalita, K.
2015-01-01
We adopt a semi-classical approach for explanation of projectile breakup and above barrier fusion suppression for the reactions 6Li+152Sm and 6Li+144Sm. The cut-off impact parameter for fusion is determined by employing quantum mechanical ideas. Within this cut-off impact parameter for fusion, the fraction of projectiles undergoing breakup is determined using the method of classical trajectory in two-dimensions. For obtaining the initial conditions of the equations of motion, a simplified model of the 6Li nucleus has been proposed. We introduce a simple formula for explanation of fusion suppression. We find excellent agreement between the experimental and calculated fusion cross section. A slight modification of the above formula for fusion suppression is also proposed for a three-dimensional model.
A model for explaining fusion suppression using classical trajectory method
Phookan C. K.
2015-01-01
Full Text Available We adopt a semi-classical approach for explanation of projectile breakup and above barrier fusion suppression for the reactions 6Li+152Sm and 6Li+144Sm. The cut-off impact parameter for fusion is determined by employing quantum mechanical ideas. Within this cut-off impact parameter for fusion, the fraction of projectiles undergoing breakup is determined using the method of classical trajectory in two-dimensions. For obtaining the initial conditions of the equations of motion, a simplified model of the 6Li nucleus has been proposed. We introduce a simple formula for explanation of fusion suppression. We find excellent agreement between the experimental and calculated fusion cross section. A slight modification of the above formula for fusion suppression is also proposed for a three-dimensional model.
Costella, J.P.; McKellar, B.H.J.; Rawlinson, A.A.
1997-03-01
We review how antiparticles may be introduced in classical relativistic mechanics, and emphasize that many of their paradoxical properties can be more transparently understood in the classical than in the quantum domain. (authors). 13 refs., 1 tab.
Costella, J P; Rawlinson, A A; Costella, John P.; Kellar, Bruce H. J. Mc; Rawlinson, Andrew A.
1997-01-01
We review how antiparticles may be introduced in classical relativistic mechanics, and emphasize that many of their paradoxical properties can be more transparently understood in the classical than in the quantum domain.
More Like Jazz than Classical: Reciprocal Interactions among Educational Researchers and Respondents
Dance, L. Janelle; Gutierrez, Rochelle; Hermes, Mary
2010-01-01
In this article, educational scholars L. Janelle Dance, Rochelle Gutierrez, and Mary Hermes share insights from their lived experience as qualitative researchers trying to work in collaboration with diverse populations. They refer to these insights as "improvisations on conventional qualitative methods," reminding readers that their methodological…
More Like Jazz than Classical: Reciprocal Interactions among Educational Researchers and Respondents
Dance, L. Janelle; Gutierrez, Rochelle; Hermes, Mary
2010-01-01
In this article, educational scholars L. Janelle Dance, Rochelle Gutierrez, and Mary Hermes share insights from their lived experience as qualitative researchers trying to work in collaboration with diverse populations. They refer to these insights as "improvisations on conventional qualitative methods," reminding readers that their…
More Like Jazz than Classical: Reciprocal Interactions among Educational Researchers and Respondents
Dance, L. Janelle; Gutierrez, Rochelle; Hermes, Mary
2010-01-01
In this article, educational scholars L. Janelle Dance, Rochelle Gutierrez, and Mary Hermes share insights from their lived experience as qualitative researchers trying to work in collaboration with diverse populations. They refer to these insights as "improvisations on conventional qualitative methods," reminding readers that their…
Quantum-classical path integral. I. Classical memory and weak quantum nonlocality.
Lambert, Roberto; Makri, Nancy
2012-12-14
We consider rigorous path integral descriptions of the dynamics of a quantum system coupled to a polyatomic environment, assuming that the latter is well approximated by classical trajectories. Earlier work has derived semiclassical or purely classical expressions for the influence functional from the environment, which should be sufficiently accurate for many situations, but the evaluation of quantum-(semi)classical path integral (QCPI) expressions has not been practical for large-scale simulation because the interaction with the environment introduces couplings nonlocal in time. In this work, we analyze the nature of the effects on a system from its environment in light of the observation [N. Makri, J. Chem. Phys. 109, 2994 (1998)] that true nonlocality in the path integral is a strictly quantum mechanical phenomenon. If the environment is classical, the path integral becomes local and can be evaluated in a stepwise fashion along classical trajectories of the free solvent. This simple "classical path" limit of QCPI captures fully the decoherence of the system via a classical mechanism. Small corrections to the classical path QCPI approximation may be obtained via an inexpensive random hop QCPI model, which accounts for some "back reaction" effects. Exploiting the finite length of nonlocality, we argue that further inclusion of quantum decoherence is possible via an iterative evaluation of the path integral. Finally, we show that the sum of the quantum amplitude factors with respect to the system paths leads to a smooth integrand as a function of trajectory initial conditions, allowing the use of Monte Carlo methods for the multidimensional phase space integral.
Olson Peter D
2010-12-01
Full Text Available Abstract Background Hymenolepis microstoma (Dujardin, 1845 Blanchard, 1891, the mouse bile duct tapeworm, is a rodent/beetle-hosted laboratory model that has been used in research and teaching since its domestication in the 1950s. Recent characterization of its genome has prompted us to describe the specific strain that underpins these data, anchoring its identity and bringing the 150+ year-old original description up-to-date. Results Morphometric and ultrastructural analyses were carried out on laboratory-reared specimens of the 'Nottingham' strain of Hymenolepis microstoma used for genome characterization. A contemporary description of the species is provided including detailed illustration of adult anatomy and elucidation of its taxonomy and the history of the specific laboratory isolate. Conclusions Our work acts to anchor the specific strain from which the H. microstoma genome has been characterized and provides an anatomical reference for researchers needing to employ a model tapeworm system that enables easy access to all stages of the life cycle. We review its classification, life history and development, and briefly discuss the genome and other model systems being employed at the beginning of a genomic era in cestodology.
Li, Guangyan; Wang, Dequn; Fang, Shiying; Xu, Maohong
2014-05-01
Aucklandia lappa Decne was first recorded in the Sheng nong ben cao jing (Shennong's Classic of Materia Medica). Through the textual research of herbal literature, it was found that the costus root in the Sheng nong ben cao jing perhaps was not the plant of Aucklandia lappa Decne of Compositae, but the eaglewood or Lignum Aquilasria Resinatum based on the comprehensive judgment of shape, taste, nature, and function etc. In the Sheng nong ben cao jing, it only includes costus root without the title of eaglewood, and Tao Hongjing recorded both herbs together in his Ming yi bie lu (Supplementary Records of Celebrated Physicians), which became a foreshadow of misunderstanding of the later generations. Beginning from the Tang ben cao (Materia Medica of the Tang Dynasty), the costus root was considered as the plant of Auckiandia lappa Decne from the Compostae with its profound influence until now.
Nordic Nuclear Safety Research 1994 - 2008: From standardized 4-year classics to customized R and B
Bennerstedt, T.N.O. (TeknoTelje HB, Torhamn (Sweden))
2011-10-15
This is a presentation of NKS (Nordic Nuclear Safety Research), its work and achievements in the years 1994 - 2008, during which the author served as Nordic secretary and (later) as coordinator. NKS and the Nordic perspective are briefly introduced together with the NKS support structure, organization and administration: Owners, Board, Nordic secretary, Bureau and Secretariat. The author then embarks on a journey through the modern history of NKS work. The last two of the six fixed 4-year programs are described as regards planning, contents, project work, administration, dissemination of results, evaluations and conclusions. The trip continues to the land of R and B and the present (2011) structure of two general frameworks, namely, NKS-R: reactor safety, and NKS-B: emergency preparedness; each consisting of a set of flexible activities; hence, R and B. The reasoning behind this makeover is touched upon together with the new organization and simpler administration that developed. Major activities and the produced results are introduced and the evaluations summarized. The author's own conclusions and recommendations are followed by a short and subjective list of references. In a number of appendices some important background material has been compiled: bullet point versions of minutes of Owners Group and Board meetings; economic contributions and budgets; the NKS policy document; an overview of all NKS programs and evaluations; lists of R and B activities and funding; the author's personal remarks; a list of some NKS documents (other than technical reports and minutes); and a list of acronyms used in this report. (Author)
Wigner function statistics in classically chaotic systems
Horvat, M; Horvat, Martin; Prosen, Tomaz
2003-01-01
We have studied statistical properties of the values of the Wigner function W(x) of 1D quantum maps on compact 2D phase space of finite area V. For this purpose we have defined a Wigner function probability distribution P(w) = (1/V) int delta(w-W(x)) dx, which has, by definition, fixed first and second moment. In particular, we concentrate on relaxation of time evolving quantum state in terms of W(x), starting from a coherent state. We have shown that for a classically chaotic quantum counterpart the distribution P(w) in the semi-classical limit becomes a Gaussian distribution that is fully determined by the first two moments. Numerical simulations have been performed for the quantum sawtooth map and the quantized kicked top. In a quantum system with Hilbert space dimension N (similar 1/hbar) the transition of P(w) to a Gaussian distribution was observed at times t proportional to log N. In addition, it has been shown that the statistics of Wigner functions of propagator eigenstates is Gaussian as well in the...
Classical signal model reproducing quantum probabilities for single and coincidence detections
Khrennikov, Andrei; Nilsson, Börje; Nordebo, Sven
2012-05-01
We present a simple classical (random) signal model reproducing Born's rule. The crucial point of our approach is that the presence of detector's threshold and calibration procedure have to be treated not as simply experimental technicalities, but as the basic counterparts of the theoretical model. We call this approach threshold signal detection model (TSD). The experiment on coincidence detection which was done by Grangier in 1986 [22] played a crucial role in rejection of (semi-)classical field models in favour of quantum mechanics (QM): impossibility to resolve the wave-particle duality in favour of a purely wave model. QM predicts that the relative probability of coincidence detection, the coefficient g(2) (0), is zero (for one photon states), but in (semi-)classical models g(2)(0) >= 1. In TSD the coefficient g(2)(0) decreases as 1/ɛ2d, where ɛd > 0 is the detection threshold. Hence, by increasing this threshold an experimenter can make the coefficient g(2) (0) essentially less than 1. The TSD-prediction can be tested experimentally in new Grangier type experiments presenting a detailed monitoring of dependence of the coefficient g(2)(0) on the detection threshold. Structurally our model has some similarity with the prequantum model of Grossing et al. Subquantum stochasticity is composed of the two counterparts: a stationary process in the space of internal degrees of freedom and the random walk type motion describing the temporal dynamics.
Classical signal model reproducing quantum probabilities for single and coincidence detections
Khrennikov, Andrei; Nordebo, Sven
2011-01-01
We present a simple classical (random) signal model reproducing Born's rule. The crucial point of our approach is that the presence of detector's threshold and calibration procedure have to be treated not as simply experimental technicalities, but as the basic counterparts of the theoretical model. We call this approach threshold signal detection model (TSD). The experiment on coincidence detection which was done by Grangier in 1986 \\cite{Grangier} played a crucial role in rejection of (semi-)classical field models in favor of quantum mechanics (QM): impossibility to resolve the wave-particle duality in favor of a purely wave model. QM predicts that the relative probability of coincidence detection, the coefficient $g^{(2)}(0),$ is zero (for one photon states), but in (semi-)classical models $g^{(2)}(0)\\geq 1.$ In TSD the coefficient $g^{(2)}(0)$ decreases as $1/{\\cal E}_d^2,$ where ${\\cal E}_d>0$ is the detection threshold. Hence, by increasing this threshold an experimenter can make the coefficient $g^{(2)}...
Clayman, Dee L.
1995-01-01
Appraises several databases devoted to classical literature. Thesaurus Linguae Graecae (TLG) contains the entire extant corpus of ancient Greek literature, including works on lexicography and historiography, extending into the 15th century. Other works awaiting completion are the Database of Classical Bibliography and a CD-ROM pictorial dictionary…
Non-linear dynamics, entanglement and the quantum-classical crossover of two coupled SQUID rings
Everitt, M J
2009-01-01
We explore the quantum-classical crossover of two coupled, identical, superconducting quantum interference device (SQUID) rings. We note that the motivation for this work is based on a study of a similar system comprising two coupled Duffing oscillators. In that work we showed that the entanglement characteristics of chaotic and periodic (entrained) solutions differed significantly and that in the classical limit entanglement was preserved only in the chaotic-like solutions. However, Duffing oscillators are a highly idealised toy model. Motivated by a wish to explore more experimentally realisable systems we now extend our work to an analysis of two coupled SQUID rings. We observe some differences in behaviour between the system that is based on SQUID rings rather than on Duffing oscillators. However, we show that the two systems share a common feature. That is, even when the SQUID ring's trajectories appear to follow (semi) classical orbits entanglement persists.
Polymer quantization of the free scalar field and its classical limit
Laddha, Alok
2010-01-01
Building on prior work, a generally covariant reformulation of free scalar field theory on the flat Lorentzian cylinder is quantized using Loop Quantum Gravity (LQG) type `polymer' representations. This quantization of the {\\em continuum} classical theory yields a quantum theory which lives on a discrete spacetime lattice. We explicitly construct a state in the polymer Hilbert space which reproduces the standard Fock vacuum- two point functions for long wavelength modes of the scalar field. Our construction indicates that the continuum classical theory emerges under coarse graining. All our considerations are free of the "triangulation" ambiguities which plague attempts to define quantum dynamics in LQG. Our work constitutes the first complete LQG type quantization of a generally covariant field theory together with a semi-classical analysis of the true degrees of freedom and thus provides a perfect infinite dimensional toy model to study open issues in LQG, particularly those pertaining to the definition of ...
Lectures on Classical Integrability
Torrielli, Alessandro
2016-01-01
We review some essential aspects of classically integrable systems. The detailed outline of the lectures consists of: 1. Introduction and motivation, with historical remarks; 2. Liouville theorem and action-angle variables, with examples (harmonic oscillator, Kepler problem); 3. Algebraic tools: Lax pairs, monodromy and transfer matrices, classical r-matrices and exchange relations, non-ultralocal Poisson brackets, with examples (non-linear Schroedinger model, principal chiral field); 4. Features of classical r-matrices: Belavin-Drinfeld theorems, analyticity properties, and lift of the classical structures to quantum groups; 5. Classical inverse scattering method to solve integrable differential equations: soliton solutions, spectral properties and the Gel'fand-Levitan-Marchenko equation, with examples (KdV equation, Sine-Gordon model). Prepared for the Durham Young Researchers Integrability School, organised by the GATIS network. This is part of a collection of lecture notes.
Gallavotti, Giovanni
2012-01-01
This is the English version of a friendly graduate course on Classical Mechanics, containing about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. For the Spanish version, see physics/9906066
Dekker, Jeroen J. H.; Groenendijk, Leendert F.
2012-01-01
This article looks at the impact of Philippe Aries's classic "L'Enfant et la vie familiale sous l'ancien regime", published in 1960. His well-known idea of the emergence of "Le sentiment de l'enfance" caused a lively debate among historians and social scientists resulting in fundamental contributions to our knowledge about the early phase of the…
Potylitsyn, A. P.; Kolchuzhkin, A. M.; Strokov, S. A.
2016-07-01
A photon spectrum of undulator radiation (UR) is calculated in the semi-classical approach. The UR intensity spectrum is determined by an electron trajectory in the undulator neglecting by energy losses for radiation. Using the Planck's law, the UR photon spectrum can be calculated from the classical intensity spectrum both for linear and nonlinear regimes. The radiation of an electron in a field of strong electromagnetic wave (radiation in the "light" undulator) is considered in the quantum electromagnetic frame. Comparison of results obtained by both approaches has been shown that UR spectra in the whole cone coincide with high accuracy for the case xbeam were simulated with taking into account the discrete process of photon emission along an electron trajectory in both kinds of undulators.
Everitt, M J
2010-01-01
We explore the quantum-classical crossover of two coupled, identical, superconducting quantum interference device (SQUID) rings. The motivation for this work is based on a series of recent papers. In ~[1] we showed that the entanglement characteristics of chaotic and periodic (entrained) solutions of the Duffing oscillator differed significantly and that in the classical limit entanglement was preserved only in the chaotic-like solutions. However, Duffing oscillators are a highly idealised toy system. Motivated by a wish to explore more experimentally realisable systems we extended our work in [2,3] to an analysis of SQUID rings. In [3] we showed that the two systems share a common feature. That is, when the SQUID ring's trajectories appear to follow (semi) classical orbits entanglement persists. Our analysis in[3] was restricted to the quantum state diffusion unravelling of the master equation - representing unit efficiency heterodyne detection (or ambi-quadrature homodyne detection). Here we show that very ...
几种经典搜索算法研究与应用%Research and Application of Several Classical Search Algorithms
欧阳圣; 胡望宇
2011-01-01
Search technology is one of the basic technology of artificial intelligence. In the various application areas of artificial intelligence, it has been widely used. The search algorithm is the core of search technology, and all of the search algorithm optimization are mainly in the classic search algorithms to improve them. Therefore, the classic study of search algorithms has a very important theoretical value and practical application value. In this paper, several classical search algorithms for research, analysis, conclusion are studied, making knowledge formation a system and facilitating better learning and research. Finally, the article compares several algorithms listing their strengths and weaknesses so that it is easy to select the appropriate algorithm to solve relevant practical problems.%搜索技术是人工智能的基本技术之一,在人工智能各应用领域中被广泛地使用.而搜索技术的核心是搜索算法,而所有的搜索算法的优化主要是在经典的搜索算法上改进得来.故研究经典搜索算法有非常重要的理论价值和实际应用价值.通过对几种经典搜索算法的研究,分析,总结,使得知识形成体系,便于更好的学习和研究.最后将几种算法进行比较,列出各自优缺点,便于选择合适的算法解决相关的实际问题.
Pastor, M Carmen; Rehbein, Maimu Alissa; Junghöfer, Markus; Poy, Rosario; López, Raul; Moltó, Javier
2015-01-01
Several challenges make it difficult to simultaneously investigate central and autonomous nervous system correlates of conditioned stimulus (CS) processing in classical conditioning paradigms. Such challenges include, for example, the discrepant requirements of electroencephalography (EEG) and electrodermal activity (EDA) recordings with regard to multiple repetitions of conditions and sufficient trial duration. Here, we propose a MultiCS conditioning set-up, in which we increased the number of CSs, decreased the number of learning trials, and used trials of short and long durations for meeting requirements of simultaneous EEG-EDA recording in a differential aversive conditioning task. Forty-eight participants underwent MultiCS conditioning, in which four neutral faces (CS+) were paired four times each with aversive electric stimulation (unconditioned stimulus) during acquisition, while four different neutral faces (CS-) remained unpaired. When comparing after relative to before learning measurements, EEG revealed an enhanced centro-posterior positivity to CS+ vs. CS- during 368-600 ms, and subjective ratings indicated CS+ to be less pleasant and more arousing than CS-. Furthermore, changes in CS valence and arousal were strong enough to bias subjective ratings when faces of CS+/CS- identity were displayed with different emotional expression (happy, angry) in a post-experimental behavioral task. In contrast to a persistent neural and evaluative CS+/CS- differentiation that sustained multiple unreinforced CS presentations, electrodermal differentiation was rapidly extinguished. Current results suggest that MultiCS conditioning provides a promising paradigm for investigating pre-post-learning changes under minimal influences of extinction and overlearning of simple stimulus features. Our data also revealed methodological pitfalls, such as the possibility of occurring artifacts when combining different acquisition systems for central and peripheral
Jin, Rui; Lin, Zhi-jian; Xue, Chun-miao; Zhang, Bing
2013-09-01
Knowledge Discovery in Databases is gaining attention and raising new hopes for traditional Chinese medicine (TCM) researchers. It is a useful tool in understanding and deciphering TCM theories. Aiming for a better understanding of Chinese herbal property theory (CHPT), this paper performed an improved association rule learning to analyze semistructured text in the book entitled Shennong's Classic of Materia Medica. The text was firstly annotated and transformed to well-structured multidimensional data. Subsequently, an Apriori algorithm was employed for producing association rules after the sensitivity analysis of parameters. From the confirmed 120 resulting rules that described the intrinsic relationships between herbal property (qi, flavor and their combinations) and herbal efficacy, two novel fundamental principles underlying CHPT were acquired and further elucidated: (1) the many-to-one mapping of herbal efficacy to herbal property; (2) the nonrandom overlap between the related efficacy of qi and flavor. This work provided an innovative knowledge about CHPT, which would be helpful for its modern research.
Piątkowski, Włodzimierz; Skrzypek, Michał
2012-01-01
The cognitive identity of medical sociology has developed in a historical perspective in the context of a specific double frame of reference comprising medicine and general sociology. The purpose of this study is to reconstruct the process of the development of the subdiscipline's research specificity in Poland, drawing attention to the general-sociological context of the conceptualization of basic interpretive and analytical sociomedical categories. In this aspect, the presented study is based on the analysis of Polish sociomedical and general-sociological research published from the early 1960s until 1989. The purpose of the study is also to describe in this perspective the structure of the research field of contemporary Western medical sociology, which was a major point of reference in this process. A look at the chronology of how the scientific identity of medical sociology developed in Poland from a historical perspective shows the gradual balancing-out of the subdiscipline's medical references, typical of the early stage of its development, and manifested in the implementation of research projects for the requirements of doctors, through consistently developed and cultivated connections with general sociology manifested in complementing the knowledge of society with aspects related to health and illness. A sine qua non condition for undertaking this scope of research was to work out strictly sociological formulations of these concepts, which was accomplished as a result of the successful reception of general sociology by the subdiscipline in question. The contemporary understanding of the research field of Polish medical sociology defined by Magdalena Sokołowska and developed as part of the 'school of medical sociology', which she initiated, is characterized by the maintenance of close relations with general sociology (affiliations of sociomedical departments in academic sociological institutions, etc.), and at the same time, by partnership cooperation with
Ivanov, Sergey V.; Buzykin, Oleg G.
2016-12-01
A classical approach is applied to calculate pressure broadening coefficients of CO2 vibration-rotational spectral lines perturbed by Ar. Three types of spectra are examined: electric dipole (infrared) absorption; isotropic and anisotropic Raman Q branches. Simple and explicit formulae of the classical impact theory are used along with exact 3D Hamilton equations for CO2-Ar molecular motion. The calculations utilize vibrationally independent most accurate ab initio potential energy surface (PES) of Hutson et al. expanded in Legendre polynomial series up to lmax = 24. New improved algorithm of classical rotational frequency selection is applied. The dependences of CO2 half-widths on rotational quantum number J up to J=100 are computed for the temperatures between 77 and 765 K and compared with available experimental data as well as with the results of fully quantum dynamical calculations performed on the same PES. To make the picture complete, the predictions of two independent variants of the semi-classical Robert-Bonamy formalism for dipole absorption lines are included. This method. however, has demonstrated poor accuracy almost for all temperatures. On the contrary, classical broadening coefficients are in excellent agreement both with measurements and with quantum results at all temperatures. The classical impact theory in its present variant is capable to produce quickly and accurately the pressure broadening coefficients of spectral lines of linear molecules for any J value (including high Js) using full-dimensional ab initio - based PES in the cases where other computational methods are either extremely time consuming (like the quantum close coupling method) or give erroneous results (like semi-classical methods).
Adriana Coutinho de Azevedo Guimarães
2008-06-01
Full Text Available This study aimed to elucidate what injuries are most likely to occur due to classical ballet practice. The research used national and international bibliography. The bibliography analysis indicated that technical and esthetical demands lead to a practice of non-anatomical movements, causing the ballet dancer to suffer from a number of associated lesions. Most of the injuries are caused by technical mistakes and wrong training. Troubles in children are usually due to trying to force external rotation at hip level and to undue use of point ballet slippers. The commonest lesions are in feet and ankles, followed by knees and hips. The rarest ones are in the upper limbs. These injuries are caused by exercise excess, by repetitions always in the same side and by wrong and early use of point slippers. The study reached the conclusion that incorrect application of classical ballet technique predisposes the dancers to characteristic injuries.
Classical dynamics a modern perspective
Sudarshan, Ennackal Chandy George
2016-01-01
Classical dynamics is traditionally treated as an early stage in the development of physics, a stage that has long been superseded by more ambitious theories. Here, in this book, classical dynamics is treated as a subject on its own as well as a research frontier. Incorporating insights gained over the past several decades, the essential principles of classical dynamics are presented, while demonstrating that a number of key results originally considered only in the context of quantum theory and particle physics, have their foundations in classical dynamics.Graduate students in physics and practicing physicists will welcome the present approach to classical dynamics that encompasses systems of particles, free and interacting fields, and coupled systems. Lie groups and Lie algebras are incorporated at a basic level and are used in describing space-time symmetry groups. There is an extensive discussion on constrained systems, Dirac brackets and their geometrical interpretation. The Lie-algebraic description of ...
Hermeneutic reading of classic texts.
Koskinen, Camilla A-L; Lindström, Unni Å
2013-09-01
The purpose of this article is to broaden the understandinfg of the hermeneutic reading of classic texts. The aim is to show how the choice of a specific scientific tradition in conjunction with a methodological approach creates the foundation that clarifies the actual realization of the reading. This hermeneutic reading of classic texts is inspired by Gadamer's notion that it is the researcher's own research tradition and a clearly formulated theoretical fundamental order that shape the researcher's attitude towards texts and create the starting point that guides all reading, uncovering and interpretation. The researcher's ethical position originates in a will to openness towards what is different in the text and which constantly sets the researcher's preunderstanding and research tradition in movement. It is the researcher's attitude towards the text that allows the text to address, touch and arouse wonder. Through a flexible, lingering and repeated reading of classic texts, what is different emerges with a timeless value. The reading of classic texts is an act that may rediscover and create understanding for essential dimensions and of human beings' reality on a deeper level. The hermeneutic reading of classic texts thus brings to light constantly new possibilities of uncovering for a new envisioning and interpretation for a new understanding of the essential concepts and phenomena within caring science.
Zwart, Hub
2015-12-01
In 2003, biophysicist and Nobel Laureate Maurice Wilkins published his autobiography entitled The Third Man. In the preface, he diffidently points out that the title (which presents him as the 'third' man credited with the co-discovery of the structure of DNA, besides Watson and Crick) was chosen by his publisher, as a reference to the famous 1949 movie no doubt, featuring Orson Welles in his classical role as penicillin racketeer Harry Lime. In this paper I intend to show that there is much more to this title than merely its familiar ring. If subjected to a (psychoanalytically inspired) comparative analysis, multiple correspondences between movie and memoirs can be brought to the fore. Taken together, these documents shed an intriguing light on the vicissitudes of budding life sciences research during the post-war era. I will focus my comparative analysis on issues still relevant today, such as dual use, the handling of sensitive scientific information (in a moral setting defined by the tension between collaboration and competition) and, finally, on the interwovenness of science and warfare (i.e. the 'militarisation' of research and the relationship between beauty and destruction). Thus, I will explain how science autobiographies on the one hand and genres of the imagination (such as novels and movies) on the other may deepen our comprehension of tensions and dilemmas of life sciences research then and now. For that reason, science autobiographies can provide valuable input (case material) for teaching philosophy and history of science to science students.
Classical cytogenetics: karyotyping techniques.
Bates, Steven E
2011-01-01
Classical cytogenetics by karyotyping has been utilized in clinical research laboratories for more than 50 years and remains the key method used in the stem cell laboratory to assess the genetic stability of stem cell cultures. It is currently the most readily accessible method for detecting chromosomal abnormalities in pluripotent stem cell cultures. This chapter will describe (1) how to prepare a culture to maximize the number of metaphase cells, (2) how to prepare slides containing chromosome spreads (3) methods used to stain chromosomes, and (4) how to interpret the cytogenetic report.
Maryann Wilson
2013-01-01
Full Text Available BACKGROUND: The impact of a scientific article is proportional to the citations it has received. In this study, we set out to identify the most cited works in epileptology in order to evaluate research trends in this field. METHODS: According to the Web of Science database, articles with more than 400 citations qualify as "citation classics". We conducted a literature search on the ISI Web of Science bibliometric database for scientific articles relevant to epilepsy. RESULTS: We retrieved 67 highly cited articles (400 or more citations, which were published in 31 journals: 17 clinical studies, 42 laboratory studies, 5 reviews and 3 classification articles. Clinical studies consisted of epidemiological analyses (n=3, studies on the clinical phenomenology of epilepsy (n=5 – including behavioral and prognostic aspects – and articles focusing on pharmacological (n=6 and non-pharmacological (n=3 treatment. The laboratory studies dealt with genetics (n=6, animal models (n=27, and neurobiology (n=9 – including both neurophysiology and neuropathology studies. The majority (61% of citation classics on epilepsy were published after 1986, possibly reflecting the expansion of research interest in laboratory studies driven by the development of new methodologies, specifically in the fields of genetics and animal models. Consequently, clinical studies were highly cited both before and after the mid 80s, whilst laboratory researches became widely cited after 1990. CONCLUSIONS: Our study indicates that the main drivers of scientific impact in the field of epileptology have increasingly become genetic and neurobiological studies, along with research on animal models of epilepsy. These articles are able to gain the highest numbers of citations in the time span of a few years and suggest potential directions for future research.
What classicality? Decoherence and Bohr's classical concepts
Schlosshauer, Maximilian
2010-01-01
Niels Bohr famously insisted on the indispensability of what he termed "classical concepts." In the context of the decoherence program, on the other hand, it has become fashionable to talk about the "dynamical emergence of classicality" from the quantum formalism alone. Does this mean that decoherence challenges Bohr's dictum and signifies a break with the Copenhagen interpretation-for example, that classical concepts do not need to be assumed but can be derived? In this paper we'll try to shine some light down the murky waters where formalism and philosophy cohabitate. To begin, we'll clarify the notion of classicality in the decoherence description. We'll then discuss Bohr's and Heisenberg's take on the quantum-classical problem and reflect on different meanings of the terms "classicality" and "classical concepts" in the writings of Bohr and his followers. This analysis will allow us to put forward some tentative suggestions for how we may better understand the relation between decoherence-induced classical...
Quantum–classical correspondence in chaotic dynamics of laser-driven atoms
Prants, S. V.
2017-04-01
This paper is a review article on some aspects of quantum–classical correspondence in chaotic dynamics of cold atoms interacting with a standing-wave laser field forming an optical lattice. The problem is treated from both (semi)classical and quantum points of view. In both approaches, the interaction of an atomic electic dipole with the laser field is treated quantum mechanically. Translational motion is described, at first, classically (atoms are considered to be point-like objects) and then quantum mechanically as a propagation of matter waves. Semiclassical equations of motion are shown to be chaotic in the sense of classical dynamical chaos. Point-like atoms in an absolutely deterministic and rigid optical lattice can move in a random-like manner demonstrating a chaotic walking with typical features of classical chaos. This behavior is explained by random-like ‘jumps’ of one of the atomic internal variable when atoms cross nodes of the standing wave and occurs in a specific range of the atom-field detuning. When treating atoms as matter waves, we show that they can make nonadiabatic transitions when crossing the standing-wave nodes. The point is that atomic wave packets split at each node in the same range of the atom-field detuning where the classical chaos occurs. The key point is that the squared amplitude of those semiclassical ‘jumps’ equal to the quantum Landau–Zener parameter which defines the probability of nonadiabatic transitions at the nodes. Nonadiabatic atomic wave packets are much more complicated compared to adiabatic ones and may be called chaotic in this sense. A few possible experiments to observe some manifestations of classical and quantum chaos with cold atoms in horizontal and vertical optical lattices are proposed and discussed.
Classical Limit of Black Hole Quantum N-Portrait and BMS Symmetry
Dvali, Gia; Luest, Dieter
2015-01-01
Black hole entropy, denoted by N, in (semi)classical limit is infinite. This scaling reveals a very important information about the qubit degrees of freedom that carry black hole entropy. Namely, the multiplicity of qubits scales as N, whereas their energy gap and their coupling as 1/N. Such a behavior is indeed exhibited by Bogoliubov-Goldstone degrees of freedom of a quantum-critical state of N soft gravitons (a condensate or a coherent state) describing the black hole quantum portrait. They can be viewed as the Goldstone modes of a broken symmetry acting on the graviton condensate. In this picture Minkowski space naturally emerges as a coherent state of infinite-N gravitons of infinite wavelength and it carries an infinite entropy. In this paper we ask what is the geometric meaning (if any) of the classical limit of this symmetry. We argue that the infinite-N limit of Bogoliubov-Goldstone modes of critical graviton condensate is described by recently-discussed classical BMS super-translations broken by the...
Magnetic monopoles and dyons revisited: a useful contribution to the study of classical mechanics
dos Santos, Renato P.
2015-05-01
Graduate-level physics curricula in many countries around the world, as well as senior-level undergraduate ones in some major institutions, include classical mechanics courses, mostly based on Goldstein’s textbook masterpiece. During the discussion of central force motion, however, the Kepler problem is virtually the only serious application presented. In this paper, we present another problem that is also soluble, namely the interaction of Schwinger’s dual-charged (dyon) particles. While the electromagnetic interaction of magnetic monopoles and electric charges was studied in detail some 40 years ago, we consider that a pedagogical discussion of it from an essentially classical mechanics point of view is a useful contribution for students. Following a path that generalizes Kepler’s problem and Rutherford scattering, we show that they exhibit remarkable properties such as stable non-planar orbits, as well as rainbow and glory scattering, which are not present in the ordinary scattering of two singly charged particles. Moreover, it can be extended further to the relativistic case and to a semi-classical quantization, which can also be included in the class discussion.
宋代文言小说叙事演变研究%Song dynasty classical Chinese novel narrative evolution research
吴静
2015-01-01
The Song Dynasty is the special period of classical Chinese novel development in our country, during this period, classical Chinese novel narrative Angle and narrative way of change, this article from the perspective of narrative evolution, combining the reality of classical Chinese novels of Song Dynasty, the classical Chinese novel narrative evolution in Song Dynasty in brief analysis.%宋代是我国文言小说发展的特殊时期，在这一时期文言小说发生了叙事角度和叙事方式的转变，本文从叙事演变的角度出发，结合宋代文言小说的实际，对宋代文言小说的叙事演变进行简要的探析。
The Zoology of the classical islamic culture
Provencal, Philippe; Aarab, Ahmed
2014-01-01
This article brings a survey of research on the science of zoology in the Classical Arabic/Islamic Culture as revealed in texts on this subject written in Classical Arabic from the second half of the 8th century to the 15th century A.D. In the light of recent research and by use of examples from...
Classical mechanics without determinism
Nikolic, H.
2005-01-01
Classical statistical particle mechanics in the configuration space can be represented by a nonlinear Schrodinger equation. Even without assuming the existence of deterministic particle trajectories, the resulting quantum-like statistical interpretation is sufficient to predict all measurable results of classical mechanics. In the classical case, the wave function that satisfies a linear equation is positive, which is the main source of the fundamental difference between classical and quantum...
Quantum computing classical physics.
Meyer, David A
2002-03-15
In the past decade, quantum algorithms have been found which outperform the best classical solutions known for certain classical problems as well as the best classical methods known for simulation of certain quantum systems. This suggests that they may also speed up the simulation of some classical systems. I describe one class of discrete quantum algorithms which do so--quantum lattice-gas automata--and show how to implement them efficiently on standard quantum computers.
Citation classics in periodontology: a controlled study.
Nieri, Michele; Saletta, Daniele; Guidi, Luisa; Buti, Jacopo; Franceschi, Debora; Mauro, Saverio; Pini-Prato, Giovanpaolo
2007-04-01
The aims of this study were to identify the most cited articles in Periodontology published from January 1990 to March 2005; and to analyse the differences between citation Classics and less cited articles. The search was carried out in four international periodontal journals: Journal of Periodontology, Journal of Clinical Periodontology, International Journal of Periodontics and Restorative Dentistry and Journal of Periodontal Research. The Classics, that are articles cited at least 100 times, were identified using the Science Citation Index database. From every issue of the journals that contained a Classic, another article was randomly selected and used as a Control. Fifty-five Classics and 55 Controls were identified. Classic articles were longer, used more images, had more authors, and contained more self-references than Controls. Moreover Classics had on the average a bigger sample size, often dealt with etiopathogenesis and prognosis, but were rarely controlled or randomized studies. Classic articles play an instructive role, but are often non-Controlled studies.
Entanglement in Classical Optics
Ghose, Partha
2013-01-01
The emerging field of entanglement or nonseparability in classical optics is reviewed, and its similarities with and differences from quantum entanglement clearly pointed out through a recapitulation of Hilbert spaces in general, the special restrictions on Hilbert spaces imposed in quantum mechanics and the role of Hilbert spaces in classical polarization optics. The production of Bell-like states in classical polarization optics is discussed, and new theorems are proved to discriminate between separable and nonseparable states in classical wave optics where no discreteness is involved. The influence of the Pancharatnam phase on a classical Bell-like state is deived. Finally, to what extent classical polarization optics can be used to simulate quantum information processing tasks is also discussed. This should be of great practical importance because coherence and entanglement are robust in classical optics but not in quantum systems.
Principal bundles the classical case
Sontz, Stephen Bruce
2015-01-01
This introductory graduate level text provides a relatively quick path to a special topic in classical differential geometry: principal bundles. While the topic of principal bundles in differential geometry has become classic, even standard, material in the modern graduate mathematics curriculum, the unique approach taken in this text presents the material in a way that is intuitive for both students of mathematics and of physics. The goal of this book is to present important, modern geometric ideas in a form readily accessible to students and researchers in both the physics and mathematics communities, providing each with an understanding and appreciation of the language and ideas of the other.
Therapeutic Applications of Classic Hallucinogens.
Bogenschutz, Michael P; Ross, Stephen
2017-05-18
This chapter reviews what is known about the therapeutic uses of the serotonergic or classic hallucinogens, i.e., psychoactive drugs such as LSD and psilocybin that exert their effects primarily through agonist activity at serotonin 2A (5HT2A) receptors. Following a review of the history of human use and scientific study of these drugs, the data from clinical research are summarized, including extensive work on the use of classic hallucinogens in the treatment of alcoholism and other addictions, studies of the use of LSD and psilocybin to relieve distress concerning death, particularly in patients with advanced or terminal cancer, and more limited data concerning the use of classic hallucinogens to treat mood and anxiety disorders. A survey of possible mechanisms of clinically relevant effects is provided. The well-established safety of classic hallucinogens is reviewed. To provide a clinical perspective, case summaries are provided of two individuals who received treatment in recent controlled trials of psilocybin: one being treated for alcoholism, the other suffering from anxiety and depression related to fear of death due to a cancer diagnosis. Although promising early phase research conducted from the 1950s through the early 1970s was discontinued before firm conclusions could be reached concerning the efficacy of any of the classic hallucinogens for any clinical condition, the research that was conducted in that era strongly suggests that classic hallucinogens have clinically relevant effects, particularly in the case of LSD treatment of alcoholism. In the past decade, clinical trials have resumed investigating the effects of classic hallucinogens in the treatment of existential distress in the face of cancer, and in the treatment of addictions including alcoholism and nicotine addiction. The studies that have been completed to date are not sufficient to establish efficacy, but the outcomes have been very encouraging, and larger trials, up to and including
刘峻杉
2011-01-01
伴随着经典教育的焦点逐渐从＂要不要＂转向＂如何教＂,社会对相关的课程研究需求非常迫切。本研究以中学生道家经典教育为例,对课程目标、内容选择、授课方式、课程评价等方面进行了探索。新时期的经典教育可以作为一种包含德育、心理、中文、历史、创造力培养等多方面内容的学科交叉视角下的教育尝试。道家经典中的自然和谐思想、天人合一思想等,都可以纳入教学内容。除了重视诵读,也应该结合丰富多彩的现代教学法和教学评价观。%After the Classical education was interrupted a hundred years later,in the past ten years,it gradually led to widespread concern in Chinese society.The focus gradually changed from ＂to do or not＂ to ＂how to do＂.The relevant theoretical research and empirical research were demanded very urgently.In this study,course objectives,content selection,teaching methods,curriculum evaluation was researched though taking the Taoist classic education for the middle school students as example.It was suggested that the classical education in the new era can be viewed as an cross-disciplinary education attempts,which including moral,psychological,Chinese,history,creativity and other aspects.Taoist classic idea of natural harmony,Heaven and human as one,etc.,could be used as a vivid teaching material.Basic reading should be combined with a variety of modern teaching methods and teaching evaluation.For teacher training in the Classical education,the true moral self-cultivation practice,with personal learning experience,was the most important aspects ready for classical education.
Digital Classics Outside the Echo-Chamber
Bodard, Gabriel; Romanello, Matteo
2016-01-01
This volume, edited by the organizers of the “Digital Classicist” seminars series, presents research in classical studies, digital classics and digital humanities, bringing together scholarship that addresses the impact of the study of classical antiquity through computational methods on audiences such as scientists, heritage professionals, students and the general public. Within this context, chapters tackle particular aspects, from epigraphy, papyrology and manuscripts, via Greek language, ...
Research on Current Situation and Countermeasures of Pupils' Classic Reading%小学生经典诵读现状与对策研究
张甜甜
2012-01-01
摘要：随着快餐文化，通俗文学的发展与深入，经典文学逐渐在人们的潜意识中漏至下风，与此同时，小学生经典诵读现状也不容乐观。我们在详细分析小学生经典诵读现状的基础上，提出了相应的对策，以期对小学生经典诵读活动的全面开展提出建设性的意见。%Along with the development of fast food culture and popular literature ,in our subconsciousness the classic literature are ignored gradually. At the same time, the present situation of pupils' reading is not optimistie. On the basis of detailed analysis of pupils' classic reading, we put forward the corresponding countermeasures, expecting to put forward the constructive suggestion of the overall development of pupils' classic reading.
The Zoology of the classical islamic culture
Provencal, Philippe; Aarab, Ahmed
2014-01-01
This article brings a survey of research on the science of zoology in the Classical Arabic/Islamic Culture as revealed in texts on this subject written in Classical Arabic from the second half of the 8th century to the 15th century A.D. In the light of recent research and by use of examples from ...... the Arabic texts themselves, a new evaluation on the scientific content of these texts will be proposed.......This article brings a survey of research on the science of zoology in the Classical Arabic/Islamic Culture as revealed in texts on this subject written in Classical Arabic from the second half of the 8th century to the 15th century A.D. In the light of recent research and by use of examples from...
Davidson and classical pragmatism
Paula Rossi
2007-06-01
Full Text Available In this paper I wish to trace some connections between Donald Davidson's work (1917-2003 and two major representatives of the classical pragmatist movement: Charles S. Peirce (1839-1914 and William James (1842-1910. I will start with a basic characterization of classical pragmatism; then, I shall examine certain conceptions in Peirce's and James' pragmatism, in order to establish affinities with Davidson´s thought. Finally, and bearing in mind the previous con-nections, I will reflect briefly on the relevance –often unrecognized- of classical pragmatist ideas in the context of contemporary philosophi-cal discussions.
Fermions from classical statistics
2010-01-01
We describe fermions in terms of a classical statistical ensemble. The states $\\tau$ of this ensemble are characterized by a sequence of values one or zero or a corresponding set of two-level observables. Every classical probability distribution can be associated to a quantum state for fermions. If the time evolution of the classical probabilities $p_\\tau$ amounts to a rotation of the wave function $q_\\tau(t)=\\pm \\sqrt{p_\\tau(t)}$, we infer the unitary time evolution of a quantum system of fe...
Chaos, scaling and existence of a continuum limit in classical non-Abelian lattice gauge theory
Nielsen, H.B. [Niels Bohr Inst., Kobenhavn (Denmark); Rugh, H.H. [Univ. of Warwick, Coventry (United Kingdom); Rugh, S.E. [Los Alamos National Lab., NM (United States)
1996-12-31
We discuss space-time chaos and scaling properties for classical non-Abelian gauge fields discretized on a spatial lattice. We emphasize that there is a {open_quote}no go{close_quotes} for simulating the original continuum classical gauge fields over a long time span since there is a never ending dynamical cascading towards the ultraviolet. We note that the temporal chaotic properties of the original continuum gauge fields and the lattice gauge system have entirely different scaling properties thereby emphasizing that they are entirely different dynamical systems which have only very little in common. Considered as a statistical system in its own right the lattice gauge system in a situation where it has reached equilibrium comes closest to what could be termed a {open_quotes}continuum limit{close_quotes} in the limit of very small energies (weak non-linearities). We discuss the lattice system both in the limit for small energies and in the limit of high energies where we show that there is a saturation of the temporal chaos as a pure lattice artifact. Our discussion focuses not only on the temporal correlations but to a large extent also on the spatial correlations in the lattice system. We argue that various conclusions of physics have been based on monitoring the non-Abelian lattice system in regimes where the fields are correlated over few lattice units only. This is further evidenced by comparison with results for Abelian lattice gauge theory. How the real time simulations of the classical lattice gauge theory may reach contact with the real time evolution of (semi-classical aspects of) the quantum gauge theory (e.g. Q.C.D.) is left an important question to be further examined.
符渝
2014-01-01
The biggest obstacles of Ancient literature reading is the meaning of words .There is a question in classical literary research :“luoying (落英)” means falling flowers or open flowers?Exegetics puts the ancient Chinese vocabulary as the research object and takes the meaning as the study core .Using the principle of exeget-ics in analyzing the meanings of “luo (落)” ,it is deduced to refer to the falling of flowers .According to this ex-ample ,exegetics is helpful to train the ability of classical literature researchers in words problem solving and to im-prove the level of the researcher ’s literature reading .So ,the role of exegetics should be attended in the cultiva-tion of classical literature researchers .%古代文献阅读最大的障碍是词义问题，“落英”是指落下的花儿还是初开的花儿，是文学史上的一个公案，训诂学以古汉语词汇为研究对象，以语义为研究核心，通过运用训诂学原理分析“落”的义项，可以推断“落英”是指落下的花儿，这个例子说明训诂学有助于培养古典文学研究者的字词考释能力，解决古代文献中历来歧义纷争的语言问题，提高研究者的文献阅读水平，应重视训诂学在古典文学人才培养中的作用。
Advanced classical field theory
Giachetta, Giovanni; Sardanashvily, Gennadi
2009-01-01
Contemporary quantum field theory is mainly developed as quantization of classical fields. Therefore, classical field theory and its BRST extension is the necessary step towards quantum field theory. This book aims to provide a complete mathematical foundation of Lagrangian classical field theory and its BRST extension for the purpose of quantization. Based on the standard geometric formulation of theory of nonlinear differential operators, Lagrangian field theory is treated in a very general setting. Reducible degenerate Lagrangian theories of even and odd fields on an arbitrary smooth manifold are considered. The second Noether theorems generalized to these theories and formulated in the homology terms provide the strict mathematical formulation of BRST extended classical field theory
2007-01-01
The relationship between classical and quantum theory is of central importance to the philosophy of physics, and any interpretation of quantum mechanics has to clarify it. Our discussion of this relationship is partly historical and conceptual, but mostly technical and mathematically rigorous, including over 500 references. On the assumption that quantum mechanics is universal and complete, we discuss three ways in which classical physics has so far been believed to emerge from quantum physic...
On Noncommutative Classical Mechanics
Djemai, A E F
2003-01-01
In this work, I investigate the noncommutative Poisson algebra of classical observables corresponding to a proposed general Noncommutative Quantum Mechanics, \\cite{1}. I treat some classical systems with various potentials and some Physical interpretations are given concerning the presence of noncommutativity at large scales (Celeste Mechanics) directly tied to the one present at small scales (Quantum Mechanics) and its possible relation with UV/IR mixing.
Learning for Classical Planning
Chrpa, Lukáš
2009-01-01
This thesis is mainly about classical planning for articial intelligence (AI). In planning, we deal with searching for a sequence of actions that changes the environment from a given initial state to a goal state. Planning problems in general are ones of the hardest problems not only in the area of AI, but in the whole computer science. Even though classical planning problems do not consider many aspects from the real world, their complexity reaches EXPSPACE-completeness. Nevertheless, there ...
Kisil, Vladimir V.
2000-01-01
We describe an $p$-mechanical (see funct-an/9405002 and quant-ph/9610016) brackets which generate quantum (commutator) and classic (Poisson) brackets in corresponding representations of the Heisenberg group. We \\emph{do not} use any kind of semiclassic approximation or limiting procedures for $\\hbar \\to 0$. Harmonic oscillator considered within the approach. Keywords: Classic and quantum mechanics, Hamilton and Heisenberg equations, Poisson brackets, commutator, Heisenberg group.
《黄帝内经》偏枯考释%Research on Hemiplegia Diseases in Huangdi's Internal Classic of Medicine
陈士玉; 王彩霞
2012-01-01
Understanding of traditional Chinese medicine on hemiplegia is gradually improving. Pianku which is also known as Pianfeng in Huangdi's Internal Classic of Medicine, after that there are other names. In Huangdi's Internal Classic of Medicine, the patients with hemiplegia have clear mind, flaccid limbs, muscular dystrophy, limb pain. After that many doctors also found that patients with hemiplegia have numbness, sensory dysfunction and other symptoms. These findings make traditional Chinese medicine on hemiplegia dealt more perfect.%中医对偏枯的认识是在不断论争中完善的.在《内经》中偏枯也称为偏风,后世也称为偏瘫或半身不遂等.《内经》中强调了偏枯具有神志清醒、肢体弛缓不用、肌肉萎缩、肢体疼痛的症状特点.后世在《内经》理论基础上又提出了麻木不仁和不知痛痒的症状,使中医对偏枯的论述更加完善.
Classical databases and knowledge organization
Hjørland, Birger
2015-01-01
This paper considers classical bibliographic databases based on the Boolean retrieval model (such as MEDLINE and PsycInfo). This model is challenged by modern search engines and information retrieval (IR) researchers, who often consider Boolean retrieval a less efficient approach. The paper...... examines this claim and argues for the continued value of Boolean systems, which suggests two further considerations: (1) the important role of human expertise in searching (expert searchers and “information literate” users) and (2) the role of library and information science and knowledge organization (KO......) in the design and use of classical databases. An underlying issue is the kind of retrieval system for which one should aim. Warner’s (2010) differentiation between the computer science traditions and an older library-oriented tradition seems important; the former aim to transform queries automatically...
A Companion to Classical Receptions
A. De Villiers
2012-03-01
Full Text Available This recent addition to the excellent Blackwell Companions series looks at the various forms of classical reception currently being researched as well as those deemed to have future importance. The diversity and volume of the themes and approaches contained in this book are truly impressive. As Hardwick and Stray state in their introduction, this collection “has been constructed on the basis that the activators of reception are many and varied and that we all gain from encountering examples from outside our own immediate areas of knowledge” (p. 4. Throughout the book they stay true to this motto and traditional approaches to classical reception are not given prominence over more recent (sometimes contentious approaches such as film studies, cultural politics and photography. The same goes for the various cultures involved and there is even a chapter on Greek drama in South Africa.
Research progress of diagnosis and control of classical swine fever%猪瘟诊断和防制研究进展
胡慧; 邱昌庆
2004-01-01
猪瘟(Classical swine fever，CSF)是严重威胁养猪业、具有重要经济意义的病毒性疾病之一，被国际兽疫局(OIE)列为A类的15种传染病之一。其特征是小血管壁变性，内脏器官多发性出血、坏死和梗塞。该病的病原是猪瘟病毒(CSFV)，CSFV在分类上属于黄病毒科(Flaviviridae)瘟病毒属(Pesti-virus)，同属的还有牛病毒性腹泻病毒(Bovine viral diarrhea virus，BVDV)和绵羊边界病病毒(Border disease virus，BDV)，
Landsman, N P
2005-01-01
The relationship between classical and quantum theory is of central importance to the philosophy of physics, and any interpretation of quantum mechanics has to clarify it. Our discussion of this relationship is partly historical and conceptual, but mostly technical and mathematically rigorous, including over 500 references. On the assumption that quantum mechanics is universal and complete, we discuss three ways in which classical physics has so far been believed to emerge from quantum physics, namely in the limit h -> 0 of small Planck's constant (in a finite system), in the limit of a large system, and through decoherence and consistent histores. The first limit is closely related to modern quantization theory and microlocal analysis, whereas the second involves methods of C*-algebras and the concepts of superselection sectors and macroscopic observables. In these limits, the classical world does not emerge as a sharply defined objective reality, but rather as an approximate appearance relative to certain "...
Discrete Classical Electromagnetic Fields
De Souza, M M
1997-01-01
The classical electromagnetic field of a spinless point electron is described in a formalism with extended causality by discrete finite transverse point-vector fields with discrete and localized point interactions. These fields are taken as a classical representation of photons, ``classical photons". They are all transversal photons; there are no scalar nor longitudinal photons as these are definitely eliminated by the gauge condition. The angular distribution of emitted photons coincides with the directions of maximum emission in the standard formalism. The Maxwell formalism and its standard field are retrieved by the replacement of these discrete fields by their space-time averages, and in this process scalar and longitudinal photons are necessarily created and added. Divergences and singularities are by-products of this averaging process. This formalism enlighten the meaning and the origin of the non-physical photons, the ones that violate the Lorentz condition in manifestly covariant quantization methods.
Randomness: Quantum versus classical
Khrennikov, Andrei
2016-05-01
Recent tremendous development of quantum information theory has led to a number of quantum technological projects, e.g. quantum random generators. This development had stimulated a new wave of interest in quantum foundations. One of the most intriguing problems of quantum foundations is the elaboration of a consistent and commonly accepted interpretation of a quantum state. Closely related problem is the clarification of the notion of quantum randomness and its interrelation with classical randomness. In this short review, we shall discuss basics of classical theory of randomness (which by itself is very complex and characterized by diversity of approaches) and compare it with irreducible quantum randomness. We also discuss briefly “digital philosophy”, its role in physics (classical and quantum) and its coupling to the information interpretation of quantum mechanics (QM).
Quasi-classical modeling of molecular quantum-dot cellular automata multidriver gates
Rahimi, Ehsan; Nejad, Shahram Mohammad
2012-05-01
Molecular quantum-dot cellular automata (mQCA) has received considerable attention in nanoscience. Unlike the current-based molecular switches, where the digital data is represented by the on/off states of the switches, in mQCA devices, binary information is encoded in charge configuration within molecular redox centers. The mQCA paradigm allows high device density and ultra-low power consumption. Digital mQCA gates are the building blocks of circuits in this paradigm. Design and analysis of these gates require quantum chemical calculations, which are demanding in computer time and memory. Therefore, developing simple models to probe mQCA gates is of paramount importance. We derive a semi-classical model to study the steady-state output polarization of mQCA multidriver gates, directly from the two-state approximation in electron transfer theory. The accuracy and validity of this model are analyzed using full quantum chemistry calculations. A complete set of logic gates, including inverters and minority voters, are implemented to provide an appropriate test bench in the two-dot mQCA regime. We also briefly discuss how the QCADesigner tool could find its application in simulation of mQCA devices.
Classical trajectories in polar-asymmetric laser fields: Synchronous THz and XUV emission
Gragossian, Aram; Seletskiy, Denis V.; Sheik-Bahae, Mansoor
2016-10-01
The interaction of intense near- and mid-infrared laser pulses with rare gases has produced bursts of radiation with spectral content extending into the extreme ultraviolet and soft x-ray region of electromagnetic spectrum. On the other end of the spectrum, laser-driven gas plasmas has been shown to produce coherent sub-harmonic optical waveforms, covering from terahertz (THz) to mid- and near-infrared frequency spectral band. Both processes can be enhanced via a combination of a driving field and its second harmonic. Despite this striking similarity, only limited experimental and theoretical attempts have been made to address these two regimes simultaneously. Here we present systematic experiments and a unifying picture of these processes, based on our extension of the semi-classical three-step model. Further understanding of the generation and coherent control of time-synchronized transients with photon energies from meV to 1 keV can lead to numerous technological advances and to an intriguing possibilities of ultra-broadband investigations into complex condensed matter systems.
Covariantizing Classical Field Theories
López, Marco Castrillón
2010-01-01
We show how to enlarge the covariance group of any classical field theory in such a way that the resulting "covariantized" theory is 'essentially equivalent' to the original. In particular, our technique will render any classical field theory generally covariant, that is, the covariantized theory will be spacetime diffeomorphism-covariant and free of absolute objects. Our results thus generalize the well-known parametrization technique of Dirac and Kucha\\v{r}. Our constructions apply equally well to internal covariance groups, in which context they produce natural derivations of both the Utiyama minimal coupling and St\\"uckelberg tricks.
Elementary classical hydrodynamics
Chirgwin, B H; Langford, W J; Maxwell, E A; Plumpton, C
1967-01-01
Elementary Classical Hydrodynamics deals with the fundamental principles of elementary classical hydrodynamics, with emphasis on the mechanics of inviscid fluids. Topics covered by this book include direct use of the equations of hydrodynamics, potential flows, two-dimensional fluid motion, waves in liquids, and compressible flows. Some general theorems such as Bernoulli's equation are also considered. This book is comprised of six chapters and begins by introducing the reader to the fundamental principles of fluid hydrodynamics, with emphasis on ways of studying the motion of a fluid. Basic c
Problems in classical mechanics
Katkar, L N
2014-01-01
Problems in classical mechanics presents a lucid treatment of the formulations of Lagrangian, Hamiltonian, and the Principles of Calculus of Variations etc. important for the study of modern physics. The study of classical mechanics prepares students to apply the principles and the mathematical tools to solve real life problems. The book also incorporates and discusses in detail topics such as Central Force Motion, Rigid Body Motion and Canonical Transformations. KEY FEATURES: Around 200 solved examples with complete mathematical theory Around 70 examples given as an exercise to test and develop students understanding The physical interpretation of the Hamiltonian is highlighted
Classical mechanics with Maxima
Timberlake, Todd Keene
2016-01-01
This book guides undergraduate students in the use of Maxima—a computer algebra system—in solving problems in classical mechanics. It functions well as a supplement to a typical classical mechanics textbook. When it comes to problems that are too difficult to solve by hand, computer algebra systems that can perform symbolic mathematical manipulations are a valuable tool. Maxima is particularly attractive in that it is open-source, multiple-platform software that students can download and install free of charge. Lessons learned and capabilities developed using Maxima are easily transferred to other, proprietary software.
Brehm, Enrico M
2016-01-01
In this work, we introduce classical holographic codes. These can be understood as concatenated probabilistic codes and can be represented as networks uniformly covering hyperbolic space. In particular, classical holographic codes can be interpreted as maps from bulk degrees of freedom to boundary degrees of freedom. Interestingly, they are shown to exhibit features similar to those expected from the AdS/CFT correspondence. Among these are a version of the Ryu-Takayanagi formula and intriguing properties regarding bulk reconstruction and boundary representations of bulk operations. We discuss the relation of our findings with expectations from AdS/CFT and, in particular, with recent results from quantum error correction.
Classic Problems of Probability
Gorroochurn, Prakash
2012-01-01
"A great book, one that I will certainly add to my personal library."—Paul J. Nahin, Professor Emeritus of Electrical Engineering, University of New Hampshire Classic Problems of Probability presents a lively account of the most intriguing aspects of statistics. The book features a large collection of more than thirty classic probability problems which have been carefully selected for their interesting history, the way they have shaped the field, and their counterintuitive nature. From Cardano's 1564 Games of Chance to Jacob Bernoulli's 1713 Golden Theorem to Parrondo's 1996 Perplexin
Learning Classical Music Club
2010-01-01
There is a new CERN Club called “Learning Classical Music at CERN”. We are aiming to give classical music lessons for different instruments (see link) for students from 5 to 100 years old. We are now ready to start our activities in the CERN barracks. We are now in the enrollment phase and hope to start lessons very soon ! Club info can be found in the list of CERN Club: http://user.web.cern.ch/user/Communication/SocialLifeActivities/Clubs/Clubs.html Salvatore Buontempo Club President
Mecanica Clasica (Classical Mechanics)
Rosu, H C
1999-01-01
First Internet undergraduate course on Classical Mechanics in Spanish (Castellano). This is about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. English and Romanian versions are in (slow) progress and hopefully will be arXived. For a similar course on Quantum Mechanics, see physics/9808031
Huddleston, Gregory H.
1993-01-01
Describes one teacher's methods for introducing to secondary English students the concepts of Classicism and Romanticism in relation to pictures of gardens, architecture, music, and literary works. Outlines how the unit leads to a writing assignment based on collected responses over time. (HB)
Mecanica Clasica (Classical Mechanics)
Rosu, H. C.
1999-01-01
First Internet graduate course on Classical Mechanics in Spanish (Castellano). This is about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. English and Romanian versions are in (slow) progress and hopefully will be arXived. For a similar course on Quantum Mechanics, see physics/9808031
Strong Coupling and Classicalization
Dvali, Gia
2016-01-01
Classicalization is a phenomenon in which a theory prevents itself from entering into a strong-coupling regime, by redistributing the energy among many weakly-interacting soft quanta. In this way, the scattering process of some initial hard quanta splits into a large number of soft elementary processes. In short, the theory trades the strong coupling for a high-multiplicity of quanta. At very high energies, the outcome of such a scattering experiment is a production of soft states of high occupation number that are approximately classical. It is evident that black hole creation in particle collision at super-Planckian energies is a result of classicalization, but there is no a priory reason why this phenomenon must be limited to gravity. If the hierarchy problem is solved by classicalization, the LHC has a chance of detecting a tower of new resonances. The lowest-lying resonances must appear right at the strong coupling scale in form of short-lived elementary particles. The heavier members of the tower must b...
Huddleston, Gregory H.
1993-01-01
Describes one teacher's methods for introducing to secondary English students the concepts of Classicism and Romanticism in relation to pictures of gardens, architecture, music, and literary works. Outlines how the unit leads to a writing assignment based on collected responses over time. (HB)
Classical Mythology. Fourth Edition.
Morford, Mark P. O.; Lenardon, Robert J.
Designed for students with little or no background in classical literature, this book introduces the Greek and Roman myths of creation, myths of the gods, Greek sagas and local legends, and presents contemporary theories about the myths. Drawing on Homer, Hesiod, Pindar, Vergil, and others, the book provides many translations and paraphrases of…
Classical galactosaemia revisited
A.M. Bosch
2006-01-01
Classical galactosaemia (McKusick 230400) is an: autosomal recessive disorder of galactose metabolism, caused by a deficiency of the enzyme galactose-1-phosphate uridyltransferase (GALT; EC 2.7.712). Most patients present in the neonatal period, after ingestion of galactose, with jaundice, hepatospl
Frank, Irmgard
2016-01-01
The notion from ab-initio molecular dynamics simulations that nuclear motion is best described by classical Newton dynamics instead of the time-dependent Schr{\\"o}dinger equation is substantiated. In principle a single experiment should bring clarity. Caution is however necessary, as temperature dependent effects must be eliminated when trying to determine the existence of a zero-point energy.
Children's Classics. Fifth Edition.
Jordan, Alice M.
"Children's Classics," a 1947 article by Alice M. Jordan reprinted from "The Horn Book Magazine," examines the dynamics and appeal of some of the most famous books for young readers, including "Alice in Wonderland,""The Wind in the Willows,""Robinson Crusoe," and "Andersen's Fairy Tales." Paul Hein's annotated bibliography, a revision of Jordan's…
Children's Classics. Fifth Edition.
Jordan, Alice M.
"Children's Classics," a 1947 article by Alice M. Jordan reprinted from "The Horn Book Magazine," examines the dynamics and appeal of some of the most famous books for young readers, including "Alice in Wonderland,""The Wind in the Willows,""Robinson Crusoe," and "Andersen's Fairy Tales." Paul Hein's annotated bibliography, a revision of Jordan's…
Sarkadi, L
2015-01-01
The three-body dynamics of the ionization of the atomic hydrogen by 30 keV antiproton impact has been investigated by calculation of fully differential cross sections (FDCS) using the classical trajectory Monte Carlo (CTMC) method. The results of the calculations are compared with the predictions of quantum mechanical descriptions: The semi-classical time-dependent close-coupling theory, the fully quantal, time-independent close-coupling theory, and the continuum-distorted-wave-eikonal-initial-state model. In the analysis particular emphasis was put on the role of the nucleus-nucleus (NN) interaction played in the ionization process. For low-energy electron ejection CTMC predicts a large NN interaction effect on FDCS, in agreement with the quantum mechanical descriptions. By examining individual particle trajectories it was found that the relative motion between the electron and the nuclei is coupled very weakly with that between the nuclei, consequently the two motions can be treated independently. A simple ...
Comins, J.A.; Leydesdorff, L.
Reference Publication Year Spectroscopy (RPYS) and Multi-RPYS provide algorithmic approaches to reconstructing the intellectual histories of scientific fields. With this brief communication, we describe a technical advancement for developing research historiographies by introducing RPYS i/o, an
Classical and non-classical effective medium theories: New perspectives
Tsukerman, Igor, E-mail: igor@uakron.edu
2017-05-18
Highlights: • Advanced non-asymptotic and nonlocal homogenization theories of metamaterials, valid in electrostatics and electrodynamics. • Classical theories (Clausius–Mossotti, Lorenz–Lorentz, Maxwell Garnett) fit well into the proposed framework. • Nonlocal effects can be included in the model, making order-of-magnitude accuracy improvements possible. • A challenging problem for future research is to determine what effective tensors are attainable for given constituents of a metamaterial. - Abstract: Future research in electrodynamics of periodic electromagnetic composites (metamaterials) can be expected to produce sophisticated homogenization theories valid for any composition and size of the lattice cell. The paper outlines a promising path in that direction, leading to non-asymptotic and nonlocal homogenization models, and highlights aspects of homogenization that are often overlooked: the finite size of the sample and the role of interface boundaries. Classical theories (e.g. Clausius–Mossotti, Maxwell Garnett), while originally derived from a very different set of ideas, fit well into the proposed framework. Nonlocal effects can be included in the model, making an order-of-magnitude accuracy improvements possible. One future challenge is to determine what effective parameters can or cannot be obtained for a given set of constituents of a metamaterial lattice cell, thereby delineating the possible from the impossible in metamaterial design.
Ollerton, Joanne Emma; Sugrue, Michael
2005-02-01
The evolution of trauma may be analyzed by review of articles most frequently cited by scientific articles worldwide. This study identified the "trauma classics" by reviewing the most-cited articles ever published in The Journal of Trauma. The Science Citation Index of the Institute for Scientific Information was searched for the 50 most-cited articles in The Journal of Trauma. Of the 12,672 articles published since 1961, 80 were cited over 100 times and 17 over 200 times. The most-cited article was by Baker, a hallmark publication on injury scoring published in 1974. Feeding postinjury, bacterial translocation, and multiple organ failure were common themes. Overall, 32% involved gastrointestinal topics and 18% involved injury scoring, with institutions in the United States publishing 80% of the articles. This study identified the trauma classics from the last 42 years of The Journal of Trauma. Citation analysis has recognized limitations but gives a fascinating insight into the evolution of trauma care.
Classical and statistical thermodynamics
Rizk, Hanna A
2016-01-01
This is a text book of thermodynamics for the student who seeks thorough training in science or engineering. Systematic and thorough treatment of the fundamental principles rather than presenting the large mass of facts has been stressed. The book includes some of the historical and humanistic background of thermodynamics, but without affecting the continuity of the analytical treatment. For a clearer and more profound understanding of thermodynamics this book is highly recommended. In this respect, the author believes that a sound grounding in classical thermodynamics is an essential prerequisite for the understanding of statistical thermodynamics. Such a book comprising the two wide branches of thermodynamics is in fact unprecedented. Being a written work dealing systematically with the two main branches of thermodynamics, namely classical thermodynamics and statistical thermodynamics, together with some important indexes under only one cover, this treatise is so eminently useful.
Franklin, Joel
2017-01-01
Classical field theory, which concerns the generation and interaction of fields, is a logical precursor to quantum field theory, and can be used to describe phenomena such as gravity and electromagnetism. Written for advanced undergraduates, and appropriate for graduate level classes, this book provides a comprehensive introduction to field theories, with a focus on their relativistic structural elements. Such structural notions enable a deeper understanding of Maxwell's equations, which lie at the heart of electromagnetism, and can also be applied to modern variants such as Chern–Simons and Born–Infeld. The structure of field theories and their physical predictions are illustrated with compelling examples, making this book perfect as a text in a dedicated field theory course, for self-study, or as a reference for those interested in classical field theory, advanced electromagnetism, or general relativity. Demonstrating a modern approach to model building, this text is also ideal for students of theoretic...
Classical Diophantine equations
1993-01-01
The author had initiated a revision and translation of "Classical Diophantine Equations" prior to his death. Given the rapid advances in transcendence theory and diophantine approximation over recent years, one might fear that the present work, originally published in Russian in 1982, is mostly superseded. That is not so. A certain amount of updating had been prepared by the author himself before his untimely death. Some further revision was prepared by close colleagues. The first seven chapters provide a detailed, virtually exhaustive, discussion of the theory of lower bounds for linear forms in the logarithms of algebraic numbers and its applications to obtaining upper bounds for solutions to the eponymous classical diophantine equations. The detail may seem stark--- the author fears that the reader may react much as does the tourist on first seeing the centre Pompidou; notwithstanding that, Sprind zuk maintainsa pleasant and chatty approach, full of wise and interesting remarks. His emphases well warrant, ...
Electrodynamics classical inconsistencies
De Souza, M M
1995-01-01
The problems of Classical Electrodynamics with the electron equation of motion and with non-integrable singularity of its self-field stress tensor are well known. They are consequences, we show, of neglecting terms that are null off the charge world line but that gives a non null contribution on its world line. The self-field stress tensor of a point classical electron is integrable, there is no causality violation and no conflict with energy conservation in its equation of motion, and there is no need of any kind of renormalization nor of any change in the Maxwell's theory for this. (This is part of the paper hep-th/9510160, stripped , for simplicity, of its non-Minkowskian geometrization of causality and of its discussion about the physical meaning of the Maxwell-Faraday concept of field).
Classical Weyl Transverse Gravity
Oda, Ichiro
2016-01-01
We study various classical aspects of the Weyl transverse (WTDiff) gravity in a general space-time dimension. First of all, we clarify a classical equivalence among three kinds of gravitational theories, those are, the conformally-invariant scalar tensor gravity, Einstein's general relativity and the WTDiff gravity via the gauge fixing procedure. Secondly, we show that in the WTDiff gravity the cosmological constant is a mere integration constant as in unimodular gravity, but it does not receive any radiative corrections unlike the unimodular gravity. A key point in this proof is to construct a covariantly conserved energy-momentum tensor, which is achieved on the basis of this equivalence relation. Thirdly, we demonstrate that the Noether current for the Weyl transformation is identically vanishing, thereby implying that the Weyl symmetry existing in both the conformally-invariant scalar tensor gravity and the WTDiff gravity is a "fake" symmetry. We find it possible to extend this proof to all matter fields,...
Randomness: quantum versus classical
Khrennikov, Andrei
2015-01-01
Recent tremendous development of quantum information theory led to a number of quantum technological projects, e.g., quantum random generators. This development stimulates a new wave of interest in quantum foundations. One of the most intriguing problems of quantum foundations is elaboration of a consistent and commonly accepted interpretation of quantum state. Closely related problem is clarification of the notion of quantum randomness and its interrelation with classical randomness. In this short review we shall discuss basics of classical theory of randomness (which by itself is very complex and characterized by diversity of approaches) and compare it with irreducible quantum randomness. The second part of this review is devoted to the information interpretation of quantum mechanics (QM) in the spirit of Zeilinger and Brukner (and QBism of Fuchs et al.) and physics in general (e.g., Wheeler's "it from bit") as well as digital philosophy of Chaitin (with historical coupling to ideas of Leibnitz). Finally, w...
Computation in Classical Mechanics
Timberlake, Todd
2007-01-01
There is a growing consensus that physics majors need to learn computational skills, but many departments are still devoid of computation in their physics curriculum. Some departments may lack the resources or commitment to create a dedicated course or program in computational physics. One way around this difficulty is to include computation in a standard upper-level physics course. An intermediate classical mechanics course is particularly well suited for including computation. We discuss the ways we have used computation in our classical mechanics courses, focusing on how computational work can improve students' understanding of physics as well as their computational skills. We present examples of computational problems that serve these two purposes. In addition, we provide information about resources for instructors who would like to include computation in their courses.
Rogers, Ibram
2008-01-01
As a 26-year-old English teacher in 1958, Chinua Achebe had no idea that the book he was writing would become a literary classic, not only in Africa but also throughout the world. He could only try to articulate the feelings he had for his countrymen and women. Achebe had a burning desire to tell the true story of Africa and African humanity. The…
Lectures on classical electrodynamics
Englert, Berthold-Georg
2014-01-01
These lecture notes cover classical electrodynamics at the level of advanced undergraduates or postgraduates. There is a strong emphasis on the general features of the electromagnetic field and, in particular, on the properties of electromagnetic radiation. It offers a comprehensive and detailed, as well as self-contained, account of material that can be covered in a one-semester course for students with a solid undergraduate knowledge of basic electricity and magnetism.
Invitation to classical analysis
Duren, Peter
2012-01-01
This book gives a rigorous treatment of selected topics in classical analysis, with many applications and examples. The exposition is at the undergraduate level, building on basic principles of advanced calculus without appeal to more sophisticated techniques of complex analysis and Lebesgue integration. Among the topics covered are Fourier series and integrals, approximation theory, Stirling's formula, the gamma function, Bernoulli numbers and polynomials, the Riemann zeta function, Tauberian theorems, elliptic integrals, ramifications of the Cantor set, and a theoretical discussion of differ
Strong, John
2004-01-01
An intermediate course in optics, this volume explores both experimental and theoretical concepts, offering practical knowledge of geometrical optics that will enhance students' comprehension of any relevant applied science. Its exposition of the concepts of classical optics is presented with a minimum of mathematical detail but presumes some knowledge of calculus, vectors, and complex numbers.Subjects include light as wave motion; superposition of wave motions; electromagnetic waves; interaction of light and matter; velocities and scattering of light; polarized light and dielectric boundarie
Classical Maxwellian polarization entanglement
Carroll, John E
2015-01-01
An explanation of polarization entanglement is presented using Maxwells classical electromagnetic theory.Two key features are required to understand these classical origins.The first is that all waves diffract and weakly diffracting waves,with a principal direction of propagation in the laboratory frame, travel along that direction at speeds ever so slightly less than c.This allows nontrivial Lorentz transformations that can act on selected forward F waves or selected waves R traveling in the opposite direction to show that both can arise from a single zero momentum frame where all the waves are transverse to the original principal direction.Such F and R waves then both belong to a single relativistic entity where correlations between the two are unremarkable.The second feature requires the avoidance of using the Coulomb gauge.Waves, tending to plane waves in the limit of zero diffraction,can then be shown to be composed of two coupled sets of E and B fields that demonstrate the classical entanglement of F an...
Classical Weyl transverse gravity
Oda, Ichiro [University of the Ryukyus, Department of Physics, Faculty of Science, Nishihara, Okinawa (Japan)
2017-05-15
We study various classical aspects of the Weyl transverse (WTDiff) gravity in a general space-time dimension. First of all, we clarify a classical equivalence among three kinds of gravitational theories, those are, the conformally invariant scalar tensor gravity, Einstein's general relativity and the WTDiff gravity via the gauge-fixing procedure. Secondly, we show that in the WTDiff gravity the cosmological constant is a mere integration constant as in unimodular gravity, but it does not receive any radiative corrections unlike the unimodular gravity. A key point in this proof is to construct a covariantly conserved energy-momentum tensor, which is achieved on the basis of this equivalence relation. Thirdly, we demonstrate that the Noether current for the Weyl transformation is identically vanishing, thereby implying that the Weyl symmetry existing in both the conformally invariant scalar tensor gravity and the WTDiff gravity is a ''fake'' symmetry. We find it possible to extend this proof to all matter fields, i.e. the Weyl-invariant scalar, vector and spinor fields. Fourthly, it is explicitly shown that in the WTDiff gravity the Schwarzschild black hole metric and a charged black hole one are classical solutions to the equations of motion only when they are expressed in the Cartesian coordinate system. Finally, we consider the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology and provide some exact solutions. (orig.)
Hong-Wen Yuan; Liang-Xiao Ma; Dan-Dan Qi; Peng Zhang; Chun-Hua Li; Jiang Zhu
2013-01-01
Although it is difficult in fully clarifying its mechanisms and effects, Deqi still can be considered as an instant “sign” of acupuncture response of the patient and acupuncturist, which has a significant value in clinic and research. This paper aims to take a history trace to the development of Deqi theory, understand the connotation of Deqi based on Chinese medicine theory, and establish an evaluation methodology accordingly. We believe that Deqi is not only the needling sensation, but also...
古典时期钢琴装饰音研究之刍议%Review on the Research of Grace Note Music of Piano in the Classical Period
许佳奇
2015-01-01
装饰音经过对巴洛克式的符号与音符记谱等各方面的统一整理，在新时代中呈现出了推陈出新的面貌。古典时期的作曲家在装饰音上，各自留下了独具特色的痕迹。在他们的推动下，古典时期的艺术风格得以更加明确地区别于巴洛克时期的传统与影响而呈现于大众面前。但是，对于古典时期装饰音的研究，不应该过分倚重各种乐谱细节的阐述，应该从时代的大原则入手，从各个层面做深入的观察与思考，以明确地表达作品风格与时代特征。%In the history of musicology, people considered the classical period as a transitional time which connects the Baroque and the Romantic Period. It carried the principle from baroque and with the atmosphere of classical period; it developed the particular musical symbol which is according with the style and musical char-acter at that time. As the important part of this period's music content and form, grace note was experienced the reform from Baroque's musical symbol and the score notation and gives the very new look in this new time. It is very easy to notice this characteristic from the sonata which composed by Haydn, Beethoven and Mozart. At the same time, different composer has different personal preference on how to select the grace note. With their effort, the Classical period is revealed as a distinguished characteristic from Baroque period's influence and old form. However, for researching not the grace note in the Classical Period, people should not rely on the details of the music score, the general principle of the time is consider prisoner, then doing the study on different case. That is the right way to figure out the style of the music and the periods feature.
Yuan, Hong-Wen; Ma, Liang-Xiao; Qi, Dan-Dan; Zhang, Peng; Li, Chun-Hua; Zhu, Jiang
2013-01-01
Although it is difficult in fully clarifying its mechanisms and effects, Deqi still can be considered as an instant "sign" of acupuncture response of the patient and acupuncturist, which has a significant value in clinic and research. This paper aims to take a history trace to the development of Deqi theory, understand the connotation of Deqi based on Chinese medicine theory, and establish an evaluation methodology accordingly. We believe that Deqi is not only the needling sensation, but also the perception of changes of qi (') flowing of the patient elicited by needling on acupoints. The signs of Deqi include the patient's subjective perception (needling sensation), the objective physiological changes (common referred to the skin redness around the acupoints and the response of brain), and the acupuncturists' perception. Although Deqi is essential for attaining the effect, it may not be the necessary sign of the ideal efficacy. It is found that the characteristics of Deqi sensations, Deqi's intensity, time duration, and the propagation will all affect the efficacy. Thus, acupuncturists should pay attention to elicit and control Deqi state, which is also the key point in modern research on the therapeutic implications of Deqi.
Hong-Wen Yuan
2013-01-01
Full Text Available Although it is difficult in fully clarifying its mechanisms and effects, Deqi still can be considered as an instant “sign” of acupuncture response of the patient and acupuncturist, which has a significant value in clinic and research. This paper aims to take a history trace to the development of Deqi theory, understand the connotation of Deqi based on Chinese medicine theory, and establish an evaluation methodology accordingly. We believe that Deqi is not only the needling sensation, but also the perception of changes of qi' flowing of the patient elicited by needling on acupoints. The signs of Deqi include the patient’s subjective perception (needling sensation, the objective physiological changes (common referred to the skin redness around the acupoints and the response of brain, and the acupuncturists' perception. Although Deqi is essential for attaining the effect, it may not be the necessary sign of the ideal efficacy. It is found that the characteristics of Deqi sensations, Deqi’s intensity, time duration, and the propagation will all affect the efficacy. Thus, acupuncturists should pay attention to elicit and control Deqi state, which is also the key point in modern research on the therapeutic implications of Deqi.
Pollock, Steven
2013-04-01
At most universities, including the University of Colorado, upper-division physics courses are taught using a traditional lecture approach that does not make use of many of the instructional techniques that have been found to improve student learning at the introductory level. We are transforming several upper-division courses using principles of active engagement and learning theory, guided by the results of observations, interviews, and analysis of student work at CU and elsewhere. In this talk I outline these transformations, including the development of faculty consensus learning goals, clicker questions, tutorials, modified homeworks, and more. We present evidence of the effectiveness of these transformations relative to traditional courses, based on student grades, interviews, and through research-based assessments of student conceptual mastery and student attitudes. Our results suggest that many of the tools that have been effective in introductory courses are effective for our majors, and that further research is warranted in the upper-division environment. (See www.colorado.edu/sei/departments/physics.htm for materials)
Visser, M
1997-01-01
The ``reliability horizon'' for semi-classical quantum gravity quantifies the extent to which we should trust semi-classical quantum gravity, and gives a handle on just where the ``Planck regime'' resides. The key obstruction to pushing semi-classical quantum gravity into the Planck regime is often the existence of large metric fluctuations, rather than a large back-reaction.
Mechanics classical and quantum
Taylor, T T
2015-01-01
Mechanics: Classical and Quantum explains the principles of quantum mechanics via the medium of analytical mechanics. The book describes Schrodinger's formulation, the Hamilton-Jacobi equation, and the Lagrangian formulation. The author discusses the Harmonic Oscillator, the generalized coordinates, velocities, as well as the application of the Lagrangian formulation to systems that are partially or entirely electromagnetic in character under certain conditions. The book examines waves on a string under tension, the isothermal cavity radiation, and the Rayleigh-Jeans result pertaining to the e
Laurent Chusseau
2013-02-01
Full Text Available We show that the thermodynamics of ideal gases may be derived solely from the Democritean concept of corpuscles moving in vacuum plus a principle of simplicity, namely that these laws are independent of the laws of motion, aside from the law of energy conservation. Only a single corpuscle in contact with a heat bath submitted to a z and t-invariant force is considered. Most of the end results are known but the method appears to be novel. The mathematics being elementary, the present paper should facilitate the understanding of the ideal gas law and of classical thermodynamics even though not-usually-taught concepts are being introduced.
Farhoudi, M.
1995-01-01
We seek an analogy of the mathematical form of the alternative form of Einstein's field equations for Lovelock's field equations. We find that the price for this analogy is to accept the existence of the trace anomaly of the energy-momentum tensor even in classical treatments. As an example, we take this analogy to any generic second order Lagrangian and exactly derive the trace anomaly relation suggested by Duff. This indicates that an intrinsic reason for the existence of such a relation sh...
2002-01-01
FIVE years ago, an ancient Chinese air was beamed to outer space as a PR exercise. To humankind, music is a universal language, so the tune seemed an ideal medium for communication with extraterrestrial intelligence. So far there has been no response, but it is believed that the tune will play for a billion years, and eventually be heard and understood. The melody is called High Mountain and Flowing Stream, and it is played on the guqin, a seven-stringed classical musical instrument similar to the zither.
Probability representation of classical states
Man'ko, OV; Man'ko, [No Value; Pilyavets, OV
2005-01-01
Probability representation of classical states described by symplectic tomograms is discussed. Tomographic symbols of classical observables which are functions on phase-space are studied. Explicit form of kernel of commutative star-product of the tomographic symbols is obtained.
Classic hallucinogens in the treatment of addictions.
Bogenschutz, Michael P; Johnson, Matthew W
2016-01-01
Addictive disorders are very common and have devastating individual and social consequences. Currently available treatment is moderately effective at best. After many years of neglect, there is renewed interest in potential clinical uses for classic hallucinogens in the treatment of addictions and other behavioral health conditions. In this paper we provide a comprehensive review of both historical and recent clinical research on the use of classic hallucinogens in the treatment of addiction, selectively review other relevant research concerning hallucinogens, and suggest directions for future research. Clinical trial data are very limited except for the use of LSD in the treatment of alcoholism, where a meta-analysis of controlled trials has demonstrated a consistent and clinically significant beneficial effect of high-dose LSD. Recent pilot studies of psilocybin-assisted treatment of nicotine and alcohol dependence had strikingly positive outcomes, but controlled trials will be necessary to evaluate the efficacy of these treatments. Although plausible biological mechanisms have been proposed, currently the strongest evidence is for the role of mystical or other meaningful experiences as mediators of therapeutic effects. Classic hallucinogens have an excellent record of safety in the context of clinical research. Given our limited understanding of the clinically relevant effects of classic hallucinogens, there is a wealth of opportunities for research that could contribute important new knowledge and potentially lead to valuable new treatments for addiction.
Classical Trajectories and Quantum Spectra
Mielnik, Bogdan; Reyes, Marco A.
1996-01-01
A classical model of the Schrodinger's wave packet is considered. The problem of finding the energy levels corresponds to a classical manipulation game. It leads to an approximate but non-perturbative method of finding the eigenvalues, exploring the bifurcations of classical trajectories. The role of squeezing turns out decisive in the generation of the discrete spectra.
Post-Classical Probability Theory
Barnum, Howard
2012-01-01
This paper offers a brief introduction to the framework of "general probabilistic theories", otherwise known as the "convex-operational" approach the foundations of quantum mechanics. Broadly speaking, the goal of research in this vein is to locate quantum mechanics within a very much more general, but conceptually very straightforward, generalization of classical probability theory. The hope is that, by viewing quantum mechanics "from the outside", we may be able better to understand it. We illustrate several respects in which this has proved to be the case, reviewing work on cloning and broadcasting, teleportation and entanglement swapping, key distribution, and ensemble steering in this general framework. We also discuss a recent derivation of the Jordan-algebraic structure of finite-dimensional quantum theory from operationally reasonable postulates.
Perspective: Quantum or classical coherence?
Miller, William H
2012-06-07
Some coherence effects in chemical dynamics are described correctly by classical mechanics, while others only appear in a quantum treatment--and when these are observed experimentally it is not always immediately obvious whether their origin is classical or quantum. Semiclassical theory provides a systematic way of adding quantum coherence to classical molecular dynamics and thus provides a useful way to distinguish between classical and quantum coherence. Several examples are discussed which illustrate both cases. Particularly interesting is the situation with electronically non-adiabatic processes, where sometimes whether the coherence effects are classical or quantum depends on what specific aspects of the process are observed.
Mechanical Systems, Classical Models
Teodorescu, Petre P
2009-01-01
This third volume completes the Work Mechanical Systems, Classical Models. The first two volumes dealt with particle dynamics and with discrete and continuous mechanical systems. The present volume studies analytical mechanics. Topics like Lagrangian and Hamiltonian mechanics, the Hamilton-Jacobi method, and a study of systems with separate variables are thoroughly discussed. Also included are variational principles and canonical transformations, integral invariants and exterior differential calculus, and particular attention is given to non-holonomic mechanical systems. The author explains in detail all important aspects of the science of mechanics, regarded as a natural science, and shows how they are useful in understanding important natural phenomena and solving problems of interest in applied and engineering sciences. Professor Teodorescu has spent more than fifty years as a Professor of Mechanics at the University of Bucharest and this book relies on the extensive literature on the subject as well as th...
Supersymmetric classical cosmology
Escamilla-Rivera, Celia; Urena-Lopez, L Arturo
2010-01-01
In this work a supersymmetric cosmological model is analyzed in which we consider a general superfield action of a homogeneous scalar field supermultiplet interacting with the scale factor in a supersymmetric FRW model. There appear fermionic superpartners associated with both the scale factor and the scalar field, and classical equations of motion are obtained from the super-Wheeler-DeWitt equation through the usual WKB method. The resulting supersymmetric Einstein-Klein-Gordon equations contain extra radiation and stiff matter terms, and we study their solutions in flat space for different scalar field potentials. The solutions are compared to the standard case, in particular those corresponding to the exponential potential, and their implications for the dynamics of the early Universe are discussed in turn.
Classical and Quantum Polyhedra
Schliemann, John
2014-01-01
Quantum polyhedra constructed from angular momentum operators are the building blocks of space in its quantum description as advocated by Loop Quantum Gravity. Here we extend previous results on the semiclassical properties of quantum polyhedra. Regarding tetrahedra, we compare the results from a canonical quantization of the classical system with a recent wave function based approach to the large-volume sector of the quantum system. Both methods agree in the leading order of the resulting effective operator (given by an harmonic oscillator), while minor differences occur in higher corrections. Perturbative inclusion of such corrections improves the approximation to the eigenstates. Moreover, the comparison of both methods leads also to a full wave function description of the eigenstates of the (square of the) volume operator at negative eigenvalues of large modulus. For the case of general quantum polyhedra described by discrete angular momentum quantum numbers we formulate a set of quantum operators fulfill...
Grassmannization of classical models
Pollet, Lode; Prokof'ev, Nikolay V; Svistunov, Boris V
2016-01-01
Applying Feynman diagrammatics to non-fermionic strongly correlated models with local constraints might seem generically impossible for two separate reasons: (i) the necessity to have a Gaussian (non-interacting) limit on top of which the perturbative diagrammatic expansion is generated by Wick's theorem, and (ii) the Dyson's collapse argument implying that the expansion in powers of coupling constant is divergent. We show that for arbitrary classical lattice models both problems can be solved/circumvented by reformulating the high-temperature expansion (more generally, any discrete representation of the model) in terms of Grassmann integrals. Discrete variables residing on either links, plaquettes, or sites of the lattice are associated with the Grassmann variables in such a way that the partition function (and correlations) of the original system and its Grassmann-field counterpart are identical. The expansion of the latter around its Gaussian point generates Feynman diagrams. A proof-of-principle implement...
Classical and quantum cosmology
Calcagni, Gianluca
2017-01-01
This comprehensive textbook is devoted to classical and quantum cosmology, with particular emphasis on modern approaches to quantum gravity and string theory and on their observational imprint. It covers major challenges in theoretical physics such as the big bang and the cosmological constant problem. An extensive review of standard cosmology, the cosmic microwave background, inflation and dark energy sets the scene for the phenomenological application of all the main quantum-gravity and string-theory models of cosmology. Born of the author's teaching experience and commitment to bridging the gap between cosmologists and theoreticians working beyond the established laws of particle physics and general relativity, this is a unique text where quantum-gravity approaches and string theory are treated on an equal footing. As well as introducing cosmology to undergraduate and graduate students with its pedagogical presentation and the help of 45 solved exercises, this book, which includes an ambitious bibliography...
Classically Isospinning Hopf Solitons
Battye, Richard A
2013-01-01
We perform full 3-dimensional numerical relaxations of isospinning Hopf solitons with Hopf charge up to 8 in the Skyrme-Faddeev model with mass terms included. We explicitly allow the soliton solution to deform and to break the symmetries of the static configuration. It turns out that the model with its rich spectrum of soliton solutions, often of similiar energy, allows for transmutations, formation of new solution types and the rearrangement of the spectrum of minimal-energy solitons in a given topological sector when isospin is added. We observe that the shape of isospinning Hopf solitons can differ qualitatively from that of the static solution. In particular the solution type of the lowest energy soliton can change. Our numerical results are of relevance for the quantization of the classical soliton solutions.
梁玉金
2015-01-01
According to the model of professional education in Colleges and universities Chinese since fifty's of last century, the malpractice constantly ap-peared in too narrowly in the development of this century, Chinese, reform of higher education, cultural quality education teaching has become one of the most im-portant research content of construction and. Chinese University in cultural quality education at present in the classroom is the main channel of teaching, of which the first category of literature, history, philosophy and other classes, courses which are relatively more. This kind of quality in the course of classics represent the features of the teaching of culture quality education in university teaching idea and the education mode. Compared with the similar courses of liberal arts profession-al courses:classic introductory subject belonging of cultural quality education as the interdisciplinary nature, the general is interdisciplinary; classic introductory course is of universal, comprehensive sex education function of all students;the curriculum advocates the practice examination methods of personalized reading, re-alize the objectives of the cultural quality education.%针对自上世纪五十年代中国高校专业教育模式,在过于狭窄地发展中不断出现的弊端,本世纪前后,中国高等教育的改革中,文化素质教育教学成为重要的建设和研究内容之一.中国高校在目前开展的文化素质教育中主渠道是课堂教学,其中第一大类为文、史、哲等类,开设课程门类比较多.该类素质课程中的经典导读代表性地体现了高校文化素质教育教学的教学理念和教育方式的特征.与同类课程的文科专业课程比较:文化素质教育的经典导读课程学科归属为跨学科性质,一般是多学科交叉;经典导读课程具有对所有大学生的普及性、综合性教育功能;该类课程倡导个性化阅读的实践考查方式,实现了文化素质教育的目标.
CLASSICAL PHOTOGRAMMETRY AND UAV – SELECTED ASCPECTS
S. Mikrut
2016-01-01
The UAV technology seems to be highly future-oriented due to its low costs as compared to traditional aerial images taken from classical photogrammetry aircrafts. The AGH University of Science and Technology in Cracow - Department of Geoinformation, Photogrammetry and Environmental Remote Sensing focuses mainly on geometry and radiometry of recorded images. Various scientific research centres all over the world have been conducting the relevant research for years. The paper presents selected ...
张田宁; 周美启; 吴生兵; 曹健; 高纺; 盛红梅
2013-01-01
Exterior-interior relationship of meridians and zangfu organs is an important component of the theory of acu-puncturology in Chinese medicine. According to the descriptions in classic works of Chinese medicine and findings of modern experimental researches, in the present paper, the authors analyzed the close association between the "Heart" and "Small Intestine", exterior-interior correlation between the Heart Meridian and Small Intestine Meridian, and between the "Heart" and body surface (acupoints), limbs, five sensory organs, etc. In addition, the authors also summarized the underlying mechanisms of the above-mentioned exterior-interior relationship of the "Heart" and put forward some proposals for the future researches.%本文从古代文献及现代研究成果入手,分析了心与小肠的脏腑联系,心经与小肠经的表里经联系,以及心与躯体部位(穴位)、四肢百骸、五官九窍的组织联系等表里关系,阐释了其表里关系的内在机制,并就如何进一步开展心的表里关系研究提出一些设想.
吴垠
2012-01-01
刘易斯拐点是指发展中国家从古典经济条件跨越到新古典经济条件时发展阶段出现重大转折点的时间段，其核心标志是劳动力从过剩逐渐转为短缺。这一衍生于发展经济学的理论命题，近年来越来越具有了“中国化”和“跨学科”的研究趋势。学者们的观点虽有不同，但研究的热情却十分高涨。鉴于此，本文将对：刘易斯拐点含义的理解；拐点成因的解析；刘易斯模型本身是否有缺陷；开放经济条件下的刘易斯拐点问题；刘易斯拐点“中国化”的微观机制分析；刘易斯拐点期中国社会政策与制度变迁等问题的研究新进展作一综述，以期深化对该命题的理解并提出进一步可能的热点研究方向。%Lewis turning point （LTP） refers to the periods of great turning point during development stages which develo- ping countries across from the classical economic conditions to neo-classical economic conditions,its core logo is the surplus la- bor force in developing countries has been turned into a shortage. This theoretical propositions derived from development eco- nomics has more and more characteristics with the ＂Chinese Style＂ and ＂interdisciplinary research trend＂ in recent years. Re- turn to Lewis＇s classic dual economics speaking to analyze the LTP theory, or according to the new phenomena and new ques- tions in evolution of the urban and rural labor market development in China and other developing countries to further reading and developing ＂Lewis Turning Point＂ theory, should make it have more fresh times characteristics and the universal explana- tory power？ Although scholars have different views, the researching enthusiasm is very high. In view of this, this paper will re- view the new progress of LTP researching： the understanding of Lewis turning point meaning; the causes of turning point analyti- cal;whether the Lewis＇ model itself is flawed
Aniello, P.; Ciaglia, F. M.; Di Cosmo, F.; Marmo, G.; Pérez-Pardo, J. M.
2016-10-01
We propose a new point of view regarding the problem of time in quantum mechanics, based on the idea of replacing the usual time operator T with a suitable real-valued function T on the space of physical states. The proper characterization of the function T relies on a particular relation with the dynamical evolution of the system rather than with the infinitesimal generator of the dynamics (Hamiltonian). We first consider the case of classical hamiltonian mechanics, where observables are functions on phase space and the tools of differential geometry can be applied. The idea is then extended to the case of the unitary evolution of pure states of finite-level quantum systems by means of the geometric formulation of quantum mechanics. It is found that T is a function on the space of pure states which is not associated with any self-adjoint operator. The link between T and the dynamical evolution is interpreted as defining a simultaneity relation for the states of the system with respect to the dynamical evolution itself. It turns out that different dynamical evolutions lead to different notions of simultaneity, i.e., the notion of simultaneity is a dynamical notion.
Crowder, Martin J
2001-01-01
If something can fail, it can often fail in one of several ways and sometimes in more than one way at a time. There is always some cause of failure, and almost always, more than one possible cause. In one sense, then, survival analysis is a lost cause. The methods of Competing Risks have often been neglected in the survival analysis literature. Written by a leading statistician, Classical Competing Risks thoroughly examines the probability framework and statistical analysis of data of Competing Risks. The author explores both the theory of the subject and the practicalities of fitting the models to data. In a coherent, self-contained, and sequential account, the treatment moves from the bare bones of the Competing Risks setup and the associated likelihood functions through survival analysis using hazard functions. It examines discrete failure times and the difficulties of identifiability, and concludes with an introduction to the counting-process approach and the associated martingale theory.With a dearth of ...
Grafakos, Loukas
2014-01-01
The main goal of this text is to present the theoretical foundation of the field of Fourier analysis on Euclidean spaces. It covers classical topics such as interpolation, Fourier series, the Fourier transform, maximal functions, singular integrals, and Littlewood–Paley theory. The primary readership is intended to be graduate students in mathematics with the prerequisite including satisfactory completion of courses in real and complex variables. The coverage of topics and exposition style are designed to leave no gaps in understanding and stimulate further study. This third edition includes new Sections 3.5, 4.4, 4.5 as well as a new chapter on “Weighted Inequalities,” which has been moved from GTM 250, 2nd Edition. Appendices I and B.9 are also new to this edition. Countless corrections and improvements have been made to the material from the second edition. Additions and improvements include: more examples and applications, new and more relevant hints for the existing exercises, new exercises, and...
Grassmannization of classical models
Pollet, Lode; Kiselev, Mikhail N.; Prokof'ev, Nikolay V.; Svistunov, Boris V.
2016-11-01
Applying Feynman diagrammatics to non-fermionic strongly correlated models with local constraints might seem generically impossible for two separate reasons: (i) the necessity to have a Gaussian (non-interacting) limit on top of which the perturbative diagrammatic expansion is generated by Wick’s theorem, and (ii) Dyson’s collapse argument implying that the expansion in powers of coupling constant is divergent. We show that for arbitrary classical lattice models both problems can be solved/circumvented by reformulating the high-temperature expansion (more generally, any discrete representation of the model) in terms of Grassmann integrals. Discrete variables residing on either links, plaquettes, or sites of the lattice are associated with the Grassmann variables in such a way that the partition function (as well as all correlation functions) of the original system and its Grassmann-field counterpart are identical. The expansion of the latter around its Gaussian point generates Feynman diagrams. Our work paves the way for studying lattice gauge theories by treating bosonic and fermionic degrees of freedom on equal footing.
Extended symmetrical classical electrodynamics.
Fedorov, A V; Kalashnikov, E G
2008-03-01
In this paper, we discuss a modification of classical electrodynamics in which "ordinary" point charges are absent. The modified equations contain additional terms describing the induced charges and currents. The densities of the induced charges and currents depend on the vector k and the vectors of the electromagnetic field, E and B . It is shown that the vectors E and B can be defined in terms of two four-potentials and the components of k are the components of a four-tensor of the third rank. The Lagrangian of the modified electrodynamics is defined. The conditions are derived at which only one four-potential determines the behavior of the electromagnetic field. It is also shown that static modified electrodynamics can describe the electromagnetic field in the inner region of an electric monopole. In the outer region of the electric monopole the electric field is governed by the Maxwell equations. It follows from boundary conditions at the interface between the inner and outer regions of the monopole that the vector k has a discrete spectrum. The electric and magnetic fields, energy, and angular momentum of the monopole are found for different eigenvalues of k .
Sullivan, Woodruff Turner
1982-01-01
Radio techniques were the nrst to lead astronomy away from the quiescent and limited Universe revealed by traditional observations at optical wave lengths. In the earliest days of radio astronomy, a handful of radio physicists and engineers made one startling discovery after another as they opened up the radio sky. With this collection of classic papers and the extensive intro ductory material, the reader can experience these exciting discoveries, as well as understand the developing techniques and follow the motivations which prompted the various lines of inquiry. For instance he or she will follow in detail the several attempts to detect radio waves from the sun at the turn of the century; the unravelling by Jansky of a "steady hiss type static"; the incredible story of Reber who built a 9 meter dish in his backyard in 1937 and then mapped the Milky Way; the vital discoveries by Hey and colleagues of radio bursts from the Sun and of a discrete source in the constellation of Cygnus; the development of re...
The classic: Bone morphogenetic protein.
Urist, Marshall R; Strates, Basil S
2009-12-01
This Classic Article is a reprint of the original work by Marshall R. Urist and Basil S. Strates, Bone Morphogenetic Protein. An accompanying biographical sketch of Marshall R. Urist, MD is available at DOI 10.1007/s11999-009-1067-4; a second Classic Article is available at DOI 10.1007/s11999-009-1069-2; and a third Classic Article is available at DOI 10.1007/s11999-009-1070-9. The Classic Article is copyright 1971 by Sage Publications Inc. Journals and is reprinted with permission from Urist MR, Strates BS. Bone morphogenetic protein. J Dent Res. 1971;50:1392-1406.
On the dynamics of classicalization
Brouzakis, N. [Department of Physics, University of Athens, University Campus, Zographou 15784 (Greece); Rizos, J., E-mail: irizos@uoi.gr [Theory Division, Department of Physics, University of Ioannina, Ioannina 45110 (Greece); Tetradis, N., E-mail: ntetrad@phys.uoa.gr [Department of Physics, University of Athens, University Campus, Zographou 15784 (Greece)
2012-02-14
We discuss the mechanism through which classicalization may occur during the collapse of a spherical field configuration modeled as a wavepacket. We demonstrate that the phenomenon is associated with the dynamical change of the equation of motion from a second-order partial differential equation of hyperbolic to one of elliptic type. Within this approach, we rederive the known expression for the classicalization radius. We also find indications that classicalization is associated with the absence of wave propagation at distances below the classicalization radius and the generation of shock waves. The full quantitative picture can be obtained only through the numerical integration of a partial differential equation of mixed type.
Jones, R. T. (Compiler)
1979-01-01
A collection of papers on modern theoretical aerodynamics is presented. Included are theories of incompressible potential flow and research on the aerodynamic forces on wing and wing sections of aircraft and on airship hulls.
Innovation: the classic traps.
Kanter, Rosabeth Moss
2006-11-01
Never a fad, but always in or out of fashion, innovation gets rediscovered as a growth enabler every half dozen years. Too often, though, grand declarations about innovation are followed by mediocre execution that produces anemic results, and innovation groups are quietly disbanded in cost-cutting drives. Each managerial generation embarks on the same enthusiastic quest for the next new thing. And each generation faces the same vexing challenges- most of which stem from the tensions between protecting existing revenue streams critical to current success and supporting new concepts that may be crucial to future success. In this article, Harvard Business School professor Rosabeth Moss Kanter reflects on the four major waves of innovation enthusiasm she's observed over the past 25 years. She describes the classic mistakes companies make in innovation strategy, process, structure, and skills assessment, illustrating her points with a plethora of real-world examples--including AT&T Worldnet, Timberland, and Ocean Spray. A typical strategic blunder is when managers set their hurdles too high or limit the scope of their innovation efforts. Quaker Oats, for instance, was so busy in the 1990s making minor tweaks to its product formulas that it missed larger opportunities in distribution. A common process mistake is when managers strangle innovation efforts with the same rigid planning, budgeting, and reviewing approaches they use in their existing businesses--thereby discouraging people from adapting as circumstances warrant. Companies must be careful how they structure fledgling entities alongside existing ones, Kanter says, to avoid a clash of cultures and agendas--which Arrow Electronics experienced in its attempts to create an online venture. Finally, companies commonly undervalue and underinvest in the human side of innovation--for instance, promoting individuals out of innovation teams long before their efforts can pay off. Kanter offers practical advice for avoiding
Introduction to Classical Density Functional Theory by a Computational Experiment
Jeanmairet, Guillaume; Levy, Nicolas; Levesque, Maximilien; Borgis, Daniel
2014-01-01
We propose an in silico experiment to introduce the classical density functional theory (cDFT). Density functional theories, whether quantum or classical, rely on abstract concepts that are nonintuitive; however, they are at the heart of powerful tools and active fields of research in both physics and chemistry. They led to the 1998 Nobel Prize in…
Classical integrable systems and Knizhnik-Zamolodchikov-Bernard equations
Aminov, G.; Levin, A.; Olshanetsky, M.; Zotov, A.
2015-05-01
The results obtained in the works supported in part by the Russian Foundation for Basic Research (project 12-02-00594) are briefly reviewed. We mainly focus on interrelations between classical integrable systems, Painlevé-Schlesinger equations and related algebraic structures such as classical and quantum R-matrices. The constructions are explained in terms of simplest examples.
Summary of the workshop: Classical general relativity and gravitational waves
Jhingan, Sanjay [Centre for Theoretical Physics, Jamia Millia Islamia, Delhi 110025 (India); Ghosh, S G [BITS - Pilani DUBAI, P.B. 500022, Dubai International Academic City, Dubai (United Arab Emirates)], E-mail: sjhingan@iucaa.enet.in, E-mail: ghosh@bitsdubai.com
2008-11-01
In the workshop, classical general relativity and gravitational waves at ICGC-2007, eleven lectures were presented on classical general relativity and nine on gravitational waves. Lectures covered diverse topics in these areas during the three days of parallel sessions. We classify and summarize here the research work and results of the oral presentations made.
Supplemental Reading for Ninth Graders: Classic or Young Adult Literature
Hill, Katherine Jane Roney
2012-01-01
The project addressed the debate over supplemental literature: young adult or classic selections to better support teaching ninth graders Tennessee's English I curriculum standards. Research supported both classical and contemporary literature for teaching ninth graders, making it difficult to determine which type of literature might produce the…
Supplemental Reading for Ninth Graders: Classic or Young Adult Literature
Hill, Katherine Jane Roney
2012-01-01
The project addressed the debate over supplemental literature: young adult or classic selections to better support teaching ninth graders Tennessee's English I curriculum standards. Research supported both classical and contemporary literature for teaching ninth graders, making it difficult to determine which type of literature might produce the…
经典顺铂类抗肿瘤药物耐药性研究综述%The Review:Recent Research in Drug Resistance of Classic Cisplatin-Based Drugs
高传柱; 费凡; 王天帅; 杨波; 杨健; 廖霞俐
2013-01-01
As a class of cell cycle non -specific anticancer drugs with a unique structure -activity,Cisplatin shows good efficacy in the clinical treatment of ovarian cancer,prostate cancer,testicular cancer and other solid tumors.However,resistance or cross-resistance of the cisplatin analogous is becoming one of the main obstacles for cisplatin and its analogous,which limits their clinical applications.Understanding the resistance mechanisms of the classic platinum-based anticancer drugs not only helps doctors in clinical applications,but also gives us more targeted information in rational drug design to obtain novel platinum-based drugs with better efficacy and lower toxicity.This paper reviews research progress of the classic cisplatin analgous for their drug resistance mechanisms.%作为一类具有独特构效关系的细胞周期非特异性抗肿瘤药物，顺铂在临床治疗卵巢癌、前列腺癌、睾丸癌等实体肿瘤中显示了良好的疗效。然而，经典顺铂类抗肿瘤药物结构上的相似性使得耐药性或交叉耐药性成为限制该类药物临床应用的主要障碍之一。通过对经典铂类抗肿瘤药物耐药机制的研究和探讨，不仅可以指导已上市铂类药物的临床使用，而且能够有效地针对其耐药机制的产生来进行更为合理的药物设计和结构修饰改造，从而获得具有更好疗效、更低毒副作用的新型铂类抗肿瘤药物。
The Diversity of Classical Archaeology
This book is the first volume in the series Studies in Classical Archaeology, founded and edited by professors of classical archaeology, Achim Lichtenberger and Rubina Raja. This volume sets out the agenda for this series. It achieves this by familiarizing readers with a wide range of themes and ...
Classic African American Children's Literature
McNair, Jonda C.
2010-01-01
The purpose of this article is to assert that there are classic African American children's books and to identify a sampling of them. The author presents multiple definitions of the term classic based on the responses of children's literature experts and relevant scholarship. Next, the manner in which data were collected and analyzed in regard to…
Classic writings on instructional technology
Ely, D.P.; Ely, Donald P.; Plomp, T.
1996-01-01
This paper describes the selection process of 17 articles for inclusion in the book, "Classic Writings on Instructional Technology." The book brings together original "classic" educational technology articles into one volume to document the history of the field through its literature. It is also an
Teaching and Demonstrating Classical Conditioning.
Sparrow, John; Fernald, Peter
1989-01-01
Discusses classroom demonstrations of classical conditioning and notes tendencies to misrepresent Pavlov's procedures. Describes the design and construction of the conditioner that is used for demonstrating classical conditioning. Relates how students experience conditioning, generalization, extinction, discrimination, and spontaneous recovery.…
2002-01-01
The heyday of Beijing’s classical music beganin 1993, when top-quality sound equipment andrecords were imported. Also in that year, BeijingMusic Radio presented a classical music programtitled "Fan’s Club" and founded the "Music and
Operator Formulation of Classical Mechanics.
Cohn, Jack
1980-01-01
Discusses the construction of an operator formulation of classical mechanics which is directly concerned with wave packets in configuration space and is more similar to that of convential quantum theory than other extant operator formulations of classical mechanics. (Author/HM)
Dynamical Symmetries in Classical Mechanics
Boozer, A. D.
2012-01-01
We show how symmetries of a classical dynamical system can be described in terms of operators that act on the state space for the system. We illustrate our results by considering a number of possible symmetries that a classical dynamical system might have, and for each symmetry we give examples of dynamical systems that do and do not possess that…
COMPETITION: CLASSICAL VERSUS NEOCLASSICAL VIEW
Mihaela Cornelia Sandu
2013-01-01
Competition is an important element from economical theory. Over time it has experienced several definitions and classifications much of them being contradictory. In this paper I will make a parallel between classical and neoclassical point of view according to competition. Keywords. Competition; neoclassical theory; classical theory; monopolistic; perfect competition.
Classic writings on instructional technology
Ely, Donald P.; Plomp, Tjeerd
1996-01-01
This paper describes the selection process of 17 articles for inclusion in the book, "Classic Writings on Instructional Technology." The book brings together original "classic" educational technology articles into one volume to document the history of the field through its literature. It is also an
Katherine Steiner
2016-10-01
Full Text Available Classics as a discipline has always taken advantage of digital methods in research, with projects dating back to the 1970s and earlier. This article examines the integration of classics and computing, and presents a case study of EpiDoc, a markup language used in epigraphy. Positive evidence can be found for EpiDoc’s influence on collaboration, with several current collaborative projects, and the nature of the technology encouraging open, reusable scholarship. The Inscriptions of Aphrodisias project illustrates much of the potential of electronic publishing. EpiDoc’s effect on research questions themselves remains inconclusive, although definite possibilities for the future are apparent. Opening up these conclusions to the wider digital classics community shows a trend towards collaboration in recent publications and projects, as well as a gradual uptake of electronic publication.
论胡适古典小说考证的西学背景%On Western Academic Background of Hu Shi’s Textural Research on Classical Novels
王光和
2012-01-01
The modern consciousness of Hu Shi's literary criticism mainly came from western cultural thoughts.These thoughts contained ideological trend of scientism,philosophy of positivism and methods of western textual criticism,as well as criticism mode of positivism in literary criticism.His achievements on literary criticism were mainly in textural researches on classical novels,with the climax of establishing the neo-redology.His style of "understanding human beings and reflecting on society" in textural research on novels did not only improve the traditional methods,but also absorb the advantages of western criticism of positivism,which had some effect on the later literary criticism.%胡适文学批评所呈现的现代意识更多的是因为吸收西方文化思想而形成的。这些西方文化思想既包括科学主义思潮、实证主义哲学、西方校勘学方法等,也包括文学批评中的实证主义批评模式。胡适的文学批评成绩主要表现在传统小说的考证当中,其最高成就体现在＂新红学＂的开创。其小说考证的＂知人论世＂的风格既是对传统的承继和提升,也是对西方实证主义批评的有效吸纳,它对后来的文学批评产生了一定的影响。
Classical approach in quantum physics
Solov'ev, Evgeni A
2010-01-01
The application of a classical approach to various quantum problems - the secular perturbation approach to quantization of a hydrogen atom in external fields and a helium atom, the adiabatic switching method for calculation of a semiclassical spectrum of hydrogen atom in crossed electric and magnetic fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's approach to Stark problem, long-lived excited states of a helium atom recently discovered with the help of Poincar$\\acute{\\mathrm{e}}$ section, inelastic transitions in slow and fast electron-atom and ion-atom collisions - is reviewed. Further, a classical representation in quantum theory is discussed. In this representation the quantum states are treating as an ensemble of classical states. This approach opens the way to an accurate description of the initial and final states in classical trajectory Monte Carlo (CTMC) method and a purely classical explanation of tunneling phenomenon. The general aspects of the structure of the semicla...
THE BUREAUCRATIC PHENOMENON: CLASSICAL CONCEPTS
Дама Ибрагима
2013-09-01
Full Text Available Aim of this article - to analyze Hegel and Karl Marx’s classic bureaucracy theories and also Max Weber’s concept of rational bureaucracy and its development in the works of Herbert Simon, Robert Merton, Peter Blau and Michel Crozier. It shows that the above listed researchers only undertook a change of terminology within the same theoretical tradition. The article describes different approaches to the bureaucratic system of administrative schools of the late 1950s and early 1980s. Major conclusions in the article include the following: administering the state apparatus consists in the organization of government on the basis of regulated rights, mandatory procedures that are invoked to ensure balance in the interest of man and society; bad effectiveness of government, infringement of the rights and freedoms of the individual is the result of dysfunction in the state apparatus; the struggle against it can be carried out with the help of administrative, economical and legal methods.DOI: http://dx.doi.org/10.12731/2218-7405-2013-6-45
Kutzner, Florian; Vogel, Tobias; Freytag, Peter; Fiedler, Klaus
2011-01-01
In the present research, we argue for the robustness of illusory correlations (ICs, Hamilton & Gifford, 1976) regarding two boundary conditions suggested in previous research. First, we argue that ICs are maintained under extended experience. Using simulations, we derive conflicting predictions. Whereas noise-based accounts predict ICs to be maintained (Fielder, 2000; Smith, 1991), a prominent account based on discrepancy-reducing feedback learning predicts ICs to disappear (Van Rooy et al., 2003). An experiment involving 320 observations with majority and minority members supports the claim that ICs are maintained. Second, we show that actively using the stereotype to make predictions that are met with reward and punishment does not eliminate the bias. In addition, participants' operant reactions afford a novel online measure of ICs. In sum, our findings highlight the robustness of ICs that can be explained as a result of unbiased but noisy learning.
Loire Classics: Reviving Classicism in some Loire Poets
Wim Verbaal
2017-06-01
Full Text Available The term 'Loire poets' has come to refer to a rather undefinable group of poets that in the second half of the eleventh century distinguishes itself through its refined poetics. They are often characterized as medieval humanists thanks to their renewed interest in the classics. Sometimes their movement is labelled a 'classicist' one. But what does this 'classicism' mean? Is it even permitted to speak of medieval 'classicisms'? This contribution approaches the question of whether we can apply this modern label to pre-modern phenomena. Moreover, it explores the changes in attitude towards the classics that sets the Loire poets off from their predecessors and contemporaries. The article focuses on poems by Hildebert of Lavardin, Baudri of Bourgueil, Marbod of Rennes, and Geoffrey of Reims. They are compared with some contemporary poets, such as Reginald of Canterbury and Sigebert of Gembloux.
Fertility preservation in female classic galactosemia patients.
van Erven, Britt; Gubbels, Cynthia S; van Golde, Ron J; Dunselman, Gerard A; Derhaag, Josien G; de Wert, Guido; Geraedts, Joep P; Bosch, Annet M; Treacy, Eileen P; Welt, Corrine K; Berry, Gerard T; Rubio-Gozalbo, M Estela
2013-07-16
Almost every female classic galactosemia patient develops primary ovarian insufficiency (POI) as a diet-independent complication of the disease. This is a major concern for patients and their parents, and physicians are often asked about possible options to preserve fertility. Unfortunately, there are no recommendations on fertility preservation in this group. The unique pathophysiology of classic galactosemia with a severely reduced follicle pool at an early age requires an adjusted approach. In this article recommendations for physicians based on current knowledge concerning galactosemia and fertility preservation are made. Fertility preservation is only likely to be successful in very young prepubertal patients. In this group, cryopreservation of ovarian tissue is currently the only available technique. However, this technique is not ready for clinical application, it is considered experimental and reduces the ovarian reserve. Fertility preservation at an early age also raises ethical questions that should be taken into account. In addition, spontaneous conception despite POI is well described in classic galactosemia. The uncertainty surrounding fertility preservation and the significant chance of spontaneous pregnancy warrant counseling towards conservative application of these techniques. We propose that fertility preservation should only be offered with appropriate institutional research ethics approval to classic galactosemia girls at a young prepubertal age.
Metal Ion Modeling Using Classical Mechanics.
Li, Pengfei; Merz, Kenneth M
2017-02-08
Metal ions play significant roles in numerous fields including chemistry, geochemistry, biochemistry, and materials science. With computational tools increasingly becoming important in chemical research, methods have emerged to effectively face the challenge of modeling metal ions in the gas, aqueous, and solid phases. Herein, we review both quantum and classical modeling strategies for metal ion-containing systems that have been developed over the past few decades. This Review focuses on classical metal ion modeling based on unpolarized models (including the nonbonded, bonded, cationic dummy atom, and combined models), polarizable models (e.g., the fluctuating charge, Drude oscillator, and the induced dipole models), the angular overlap model, and valence bond-based models. Quantum mechanical studies of metal ion-containing systems at the semiempirical, ab initio, and density functional levels of theory are reviewed as well with a particular focus on how these methods inform classical modeling efforts. Finally, conclusions and future prospects and directions are offered that will further enhance the classical modeling of metal ion-containing systems.
Metal Ion Modeling Using Classical Mechanics
2017-01-01
Metal ions play significant roles in numerous fields including chemistry, geochemistry, biochemistry, and materials science. With computational tools increasingly becoming important in chemical research, methods have emerged to effectively face the challenge of modeling metal ions in the gas, aqueous, and solid phases. Herein, we review both quantum and classical modeling strategies for metal ion-containing systems that have been developed over the past few decades. This Review focuses on classical metal ion modeling based on unpolarized models (including the nonbonded, bonded, cationic dummy atom, and combined models), polarizable models (e.g., the fluctuating charge, Drude oscillator, and the induced dipole models), the angular overlap model, and valence bond-based models. Quantum mechanical studies of metal ion-containing systems at the semiempirical, ab initio, and density functional levels of theory are reviewed as well with a particular focus on how these methods inform classical modeling efforts. Finally, conclusions and future prospects and directions are offered that will further enhance the classical modeling of metal ion-containing systems. PMID:28045509
王付
2011-01-01
探索经方甘遂半夏汤中甘遂配甘草的理论研究与临床应用.方法 通过研究甘遂配甘草的古代认识,历代沿袭,以及甘遂、甘草主治、化学成分及药理,甘遂配甘草是否产生新的毒性,甘遂配甘草之间的用量调配关系等,进而证实临床运用以甘遂半夏汤为主治疗肠结核,甲状腺炎的可行性与实用性.结果 探索甘遂配甘草在理论上是科学的,在临床中具有良好的治疗作用.结论 历史记载甘遂与甘草相反是缺乏理论假说的,临床中合理应用辨治诸多病证则是客观事实.%Objective: This article research classic prescription on euphorbia kansui and pinellia soup, which is contained the euphorbia kansui to match the licorice , with the theoretical research and the clinical practice. Method: Through the research on euphorbia kansui matched the licorice the ancient times to know that, all previous dynasties followed, as well as the euphorbia kansui, the licorice mainly treatment effects, the chemical composition and the pharmacology, the euphorbia kansui match the licorice whether had the new toxicity, how to deploy the euphorbia kansui matched the licorice and so on, then the confirmation clinical utilized by the euphorbia kansui pinellia soup primarily treats intestinal tuberculosis, the thyroiditis feasibility and practicality. Result: The exploration euphorbia kansui matches the licorice theoretically is scientific, in clinical also has the good treatment function. Conclusion: The historical record euphorbia kansui and the licorice relative opposite lack the theory hypothesis, the clinical reasonable application differentiation of symptoms and signs is objective fact.
Mathematical methods of classical physics
Cortés, Vicente
2017-01-01
This short primer, geared towards students with a strong interest in mathematically rigorous approaches, introduces the essentials of classical physics, briefly points out its place in the history of physics and its relation to modern physics, and explains what benefits can be gained from a mathematical perspective. As a starting point, Newtonian mechanics is introduced and its limitations are discussed. This leads to and motivates the study of different formulations of classical mechanics, such as Lagrangian and Hamiltonian mechanics, which are the subjects of later chapters. In the second part, a chapter on classical field theories introduces more advanced material. Numerous exercises are collected in the appendix.
Quantum localization of Classical Mechanics
Batalin, Igor A
2016-01-01
Quantum localization of classical mechanics within the BRST-BFV and BV (or field-antifield) quantization methods are studied. It is shown that a special choice of gauge fixing functions (or BRST-BFV charge) together with the unitary limit leads to Hamiltonian localization in the path integral of the BRST-BFV formalism. In turn, we find that a special choice of gauge fixing functions being proportional to extremals of an initial non-degenerate classical action together with a very special solution of the classical master equation result in Lagrangian localization in the partition function of the BV formalism.
Quantum localization of classical mechanics
Batalin, Igor A.; Lavrov, Peter M.
2016-07-01
Quantum localization of classical mechanics within the BRST-BFV and BV (or field-antifield) quantization methods are studied. It is shown that a special choice of gauge fixing functions (or BRST-BFV charge) together with the unitary limit leads to Hamiltonian localization in the path integral of the BRST-BFV formalism. In turn, we find that a special choice of gauge fixing functions being proportional to extremals of an initial non-degenerate classical action together with a very special solution of the classical master equation result in Lagrangian localization in the partition function of the BV formalism.
Classical Knowledge for Quantum Security
D'Hondt, Ellie
2008-01-01
We propose a decision procedure for analysing security of quantum cryptographic protocols, combining a classical algebraic rewrite system for knowledge with an operational semantics for quantum distributed computing. As a test case, we use our procedure to reason about security properties of a recently developed quantum secret sharing protocol that uses graph states. We analyze three different scenarios based on the safety assumptions of the classical and quantum channels and discover the path of an attack in the presence of an adversary. The epistemic analysis that leads to this and similar types of attacks is purely based on our classical notion of knowledge.
The Wigner representation of classical mechanics, quantization and classical limit
Bolivar, A.O. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)
2001-08-01
Starting from the Liouvillian formulation of classical physics it is possible by means of a Fourier transform to introduce the Wigner representation and to derive an operator structure to classical mechanisms. The importance of this new representation lies on the fact that it turns out to be suitable route to establish a general method of quantization directly from the equations of motion without alluding to the existence of Hamiltonian and Lagrangian functions. Following this approach we quantize only the motion of a Browian particle with non-linear friction in the Markovian approximation - the thermal bath may be quantum or classical -, thus when the bath is classically described we obtain a master equation which reduces to Caldeira-Legget equation for the linear friction case, and when the reservoir is quantum we get an equation reducing to the one found by Caldeira et al. By neglecting the environmental influence we show that the system can be approximately described by equations of motion in terms of wave function, such as the Schrodinger-Langevin equation and equations of the Caldirola-Kanai type. Finally to make the present study self-consistent we evaluate the classical limit of these dynamical equations employing a new classical limiting method h/2{pi} {yields} 0. (author)
Lamb, W. E. Jr.
1981-12-01
This final report describes research on the theory of isotope separation produced by the illumination of polyatomic molecules by intense infrared laser radiation. This process is investigated by treating the molecule, sulfur hexafluoride, as a system of seven classical particles that obey the Newtonian equations of motion. A minicomputer is used to integrate these differential equations. The particles are acted on by interatomic forces, and by the time-dependent electric field of the laser. We have a very satisfactory expression for the interaction of the laser and the molecule which is compatible with infrared absorption and spectroscopic data. The interatomic potential is capable of improvement, and progress on this problem is still being made. We have made several computer runs of the dynamical behavior of the molecule using a reasonably good model for the interatomic force law. For the laser parameters chosen, we find that typically the molecule passes quickly through the resonance region into the quasi-continuum and even well into the real continuum before dissociation actually occurs. When viewed on a display terminal, the motions are exceedingly complex. As an aid to the visualization of the process, we have made a number of 16 mm movies depicting a three-dimensional representation of the motion of the seven particles. These show even more clearly the enormous complexity of the motions, and make clear the desirability of finding ways of characterizing the motion in simple ways without giving all of the numerical detail. One of the ways to do this is to introduce statistical parameters such as a temperature associated with the distribution of kinetic energies of the single particle. We have made such an analysis of our data runs, and have found favorable indications that such methods will prove useful in keeping track of the dynamical histories.
CLASSICAL PHOTOGRAMMETRY AND UAV – SELECTED ASCPECTS
S. Mikrut
2016-06-01
Full Text Available The UAV technology seems to be highly future-oriented due to its low costs as compared to traditional aerial images taken from classical photogrammetry aircrafts. The AGH University of Science and Technology in Cracow - Department of Geoinformation, Photogrammetry and Environmental Remote Sensing focuses mainly on geometry and radiometry of recorded images. Various scientific research centres all over the world have been conducting the relevant research for years. The paper presents selected aspects of processing digital images made with the UAV technology. It provides on a practical example a comparison between a digital image taken from an airborne (classical height, and the one made from an UAV level. In his research the author of the paper is trying to find an answer to the question: to what extent does the UAV technology diverge today from classical photogrammetry, and what are the advantages and disadvantages of both methods? The flight plan was made over the Tokarnia Village Museum (more than 0.5 km2 for two separate flights: the first was made by an UAV - System FT-03A built by FlyTech Solution Ltd. The second was made with the use of a classical photogrammetric Cesna aircraft furnished with an airborne photogrammetric camera (Ultra Cam Eagle. Both sets of photographs were taken with pixel size of about 3 cm, in order to have reliable data allowing for both systems to be compared. The project has made aerotriangulation independently for the two flights. The DTM was generated automatically, and the last step was the generation of an orthophoto. The geometry of images was checked under the process of aerotriangulation. To compare the accuracy of these two flights, control and check points were used. RMSE were calculated. The radiometry was checked by a visual method and using the author's own algorithm for feature extraction (to define edges with subpixel accuracy. After initial pre-processing of data, the images were put together, and
Classical Photogrammetry and Uav - Selected Ascpects
Mikrut, S.
2016-06-01
The UAV technology seems to be highly future-oriented due to its low costs as compared to traditional aerial images taken from classical photogrammetry aircrafts. The AGH University of Science and Technology in Cracow - Department of Geoinformation, Photogrammetry and Environmental Remote Sensing focuses mainly on geometry and radiometry of recorded images. Various scientific research centres all over the world have been conducting the relevant research for years. The paper presents selected aspects of processing digital images made with the UAV technology. It provides on a practical example a comparison between a digital image taken from an airborne (classical) height, and the one made from an UAV level. In his research the author of the paper is trying to find an answer to the question: to what extent does the UAV technology diverge today from classical photogrammetry, and what are the advantages and disadvantages of both methods? The flight plan was made over the Tokarnia Village Museum (more than 0.5 km2) for two separate flights: the first was made by an UAV - System FT-03A built by FlyTech Solution Ltd. The second was made with the use of a classical photogrammetric Cesna aircraft furnished with an airborne photogrammetric camera (Ultra Cam Eagle). Both sets of photographs were taken with pixel size of about 3 cm, in order to have reliable data allowing for both systems to be compared. The project has made aerotriangulation independently for the two flights. The DTM was generated automatically, and the last step was the generation of an orthophoto. The geometry of images was checked under the process of aerotriangulation. To compare the accuracy of these two flights, control and check points were used. RMSE were calculated. The radiometry was checked by a visual method and using the author's own algorithm for feature extraction (to define edges with subpixel accuracy). After initial pre-processing of data, the images were put together, and shown side by side
Combining classical metrology models
Francisco Roldán
2013-11-01
Full Text Available The results obtained in the graphic analysis of the modulation of the Cuarto Real de Santo Domingo building in Granada, Spain, (ROLDÁN, 2011 have provided new insights to further approach the research on possible use the double-scale in historical monumental architecture. We propose the characterization of the singularities of the system, from the implications and graphic representation required by the metrological scheme identified, as well as the variety of typologies that are presented in their modular frames, and the iterative combination of two-scale modules which allow operational approximations to fractions and ratios not explicitly present in the system.
Natarajan, P N
2017-01-01
This book presents results about certain summability methods, such as the Abel method, the Norlund method, the Weighted mean method, the Euler method and the Natarajan method, which have not appeared in many standard books. It proves a few results on the Cauchy multiplication of certain summable series and some product theorems. It also proves a number of Steinhaus type theorems. In addition, it introduces a new definition of convergence of a double sequence and double series and proves the Silverman-Toeplitz theorem for four-dimensional infinite matrices, as well as Schur's and Steinhaus theorems for four-dimensional infinite matrices. The Norlund method, the Weighted mean method and the Natarajan method for double sequences are also discussed in the context of the new definition. Divided into six chapters, the book supplements the material already discussed in G.H.Hardy's Divergent Series. It appeals to young researchers and experienced mathematicians who wish to explore new areas in Summability Theory.
From Classical to Quantum Transistor
Sanjeev Kumar
2009-05-01
Full Text Available In this article the classical transistor and the basic physics underlying the operation of single electron transistor are presented; a brief history of transistor and current technological issues are discussed.
Experimental contextuality in classical light.
Li, Tao; Zeng, Qiang; Song, Xinbing; Zhang, Xiangdong
2017-03-14
The Klyachko, Can, Binicioglu, and Shumovsky (KCBS) inequality is an important contextuality inequality in three-level system, which has been demonstrated experimentally by using quantum states. Using the path and polarization degrees of freedom of classical optics fields, we have constructed the classical trit (cetrit), tested the KCBS inequality and its geometrical form (Wright's inequality) in this work. The projection measurement has been implemented, the clear violations of the KCBS inequality and its geometrical form have been observed. This means that the contextuality inequality, which is commonly used in test of the conflict between quantum theory and noncontextual realism, may be used as a quantitative tool in classical optical coherence to describe correlation characteristics of the classical fields.
Soundscape of classical Chinese garden
2008-01-01
With deep humanized connotation,the classical Chinese garden uses human intuitive sensation and personal poetic observation to express natural sound phenomena.It differs from the rational modern soundscape in western countries.
New perspectives on classical electromagnetism
Cote, Paul J.
2009-01-01
The fallacies associated with the gauge concept in electromagnetism are illustrated. A clearer and more valid formulation of the basics of classical electromagnetism is provided by recognizing existing physical constraints as well as the physical reality of the vector potential.
Invariants from classical field theory
Diaz, Rafael
2007-01-01
We introduce a method that generates invariant functions from classical field theories depending on external parameters. We apply our method to several field theories such as abelian BF, Chern-Simons and 2-dimensional Yang-Mills theory.
From Classical to Quantum Transistor
Sanjeev Kumar
2009-01-01
In this article the classical transistor and the basic physics underlying the operation of single electron transistor are presented; a brief history of transistor and current technological issues are discussed.
Classical Mechanics and Symplectic Integration
Nordkvist, Nikolaj; Hjorth, Poul G.
2005-01-01
Content: Classical mechanics: Calculus of variations, Lagrange’s equations, Symmetries and Noether’s theorem, Hamilton’s equations, cannonical transformations, integrable systems, pertubation theory. Symplectic integration: Numerical integrators, symplectic integrators, main theorem on symplectic...
Classical theory of radiating strings
Copeland, Edmund J.; Haws, D.; Hindmarsh, M.
1990-01-01
The divergent part of the self force of a radiating string coupled to gravity, an antisymmetric tensor and a dilaton in four dimensions are calculated to first order in classical perturbation theory. While this divergence can be absorbed into a renormalization of the string tension, demanding that both it and the divergence in the energy momentum tensor vanish forces the string to have the couplings of compactified N = 1 D = 10 supergravity. In effect, supersymmetry cures the classical infinities.
New Perspective on Classical Electromagnetism
2013-04-01
R. Feynman , R. Leighton, and M. Sands, The Feynman Lectures in Physics vol II (Addison-Wesley, Reading, MA, 1964). 6. W.K.H. Panofsky and M...of the basics of classical electromagnetism is provided by recognizing a previously overlooked law of induction as well as the physical reality of the...classical electromagnetism is provided by recognizing a previously overlooked law of induction as well as the physical reality of the vector potential
Dynamical systems in classical mechanics
Kozlov, V V
1995-01-01
This book shows that the phenomenon of integrability is related not only to Hamiltonian systems, but also to a wider variety of systems having invariant measures that often arise in nonholonomic mechanics. Each paper presents unique ideas and original approaches to various mathematical problems related to integrability, stability, and chaos in classical dynamics. Topics include… the inverse Lyapunov theorem on stability of equilibria geometrical aspects of Hamiltonian mechanics from a hydrodynamic perspective current unsolved problems in the dynamical systems approach to classical mechanics
Classical Transitions for Flux Vacua
Deskins, J Tate; Yang, I-Sheng
2012-01-01
We present the simplest model for classical transitions in flux vacua. A complex field with a spontaneously broken U(1) symmetry is embedded in $M_2\\times S_1$. We numerically construct different winding number vacua, the vortices interpolating between them, and simulate the collisions of these vortices. We show that classical transitions are generic at large boosts, independent of whether or not vortices miss each other in the compact $S_1$.
Electrostatics interactions in classical simulations.
Cisneros, G Andrés; Babin, Volodymyr; Sagui, Celeste
2013-01-01
Electrostatic interactions are crucial for both the accuracy and performance of atomistic biomolecular simulations. In this chapter we review well-established methods and current developments aiming at efficiency and accuracy. Specifically, we review the classical Ewald summations, particle-particle particle-method particle-method Ewald algorithms, multigrid, fast multipole, and local methods. We also highlight some recent developments targeting more accurate, yet classical, representation of the molecular charge distribution.
Classical transmitters and their receptors in flatworms.
Ribeiro, P; El-Shehabi, F; Patocka, N
2005-01-01
The flatworm nervous system employs a wide repertoire of neuroactive substances, including small chemical messengers, the so called classical transmitters, and several types of neuropeptides. A large body of research accumulated over four decades has provided a wealth of information on the tissue localization and effects of these substances, their biochemistry and, recently, their molecular modes of action in all major classes of flatworms. This evidence will be reviewed, with particular emphasis on the small (classical) transmitters and the receptors that mediate their effects. One of the themes that will emerge from this discussion is that classical transmitters regulate core activities such as movement, metabolism and transport, and thus are essential for survival of the organism. In addition, the evidence shows that flatworms have multiple neurotransmitter receptors, many with unusual pharmacological features, which make them particularly attractive as drug targets. Understanding the molecular basis of these distinctive properties, and developing new, more specific receptor agonists and antagonists will undoubtedly become a major challenge in future research.
贾旭东; 衡量
2015-01-01
In the context of market changing fast,virtual operation (VO) is regarded as a new pattern which breaks the tra⁃ditional limit. VO advocates the idea of“borrowing chickens to lay eggs”and adds vibrancy to develop. As the boom of enter⁃prise’s practice appears, the reason why VO can offer the power to develop has became an important issue. The article, adopting two typical virtual enterprises as studying cases,employs the method of the classical grounded theory to completely explore the motives of virtual operation. The research indicates that some companies virtualize in entrepreneurship stage called virtualization in pioneering period and others virtualize in development stage called virtualization in developing period. Com⁃bining a number of first-hand and second-hand data we obtain the virtual operation motives model in different enterprise ’s de⁃velopment stages by applying coding technology of the classical grounded theory. Based on the integration of common virtual operation motives in two stages,we find that enterprises’fundamental motives of virtual operation are composed of three di⁃mensions:cost, efficiency, and core competence. These motives form the effective combination to promote enterprises’ long-term development,and present the progressive relationship from outside to core. To sum up,the results lay a solid em⁃pirical basis on further studying virtual operation.%在市场日益快速多变的背景下，作为一种新兴的经营模式，虚拟经营打破传统模式，以“借鸡下蛋”的思维为企业发展增添了新的活力。伴随着丰富的企业实践热潮，虚拟经营的原动力何在成为理论界热烈探讨的重要课题。文章运用经典扎根理论研究方法，以两家采取虚拟经营模式获得成功的典型企业为案例，试图完整揭示企业虚拟经营的动因。在研究中发现，有企业在创业期开始虚拟经营，也有企业在发展期开始虚拟经营，文章
Green’s functions in classical physics
Rother, Tom
2017-01-01
This book presents the Green’s function formalism in a basic way and demonstrates its usefulness for applications to several well-known problems in classical physics which are usually solved not by this formalism but other approaches. The book bridges the gap between applications of the Green’s function formalism in quantum physics and classical physics. This book is written as an introduction for graduate students and researchers who want to become more familiar with the Green’s function formalism. In 1828 George Green has published an essay that was unfortunately sunken into oblivion shortly after its publication. It was rediscovered only after several years by the later Lord Kelvin. But since this time, using Green’s functions for solving partial differential equations in physics has become an important mathematical tool. While the conceptual and epistemological importance of these functions were essentially discovered and discussed in modern physics - especially in quantum field theory and quantum...
宁宜宝; 吴文福
2011-01-01
The author describes the new epidemic characteristics of classical swine fever, points out six reasons which cause immune failure, and introduces the history and study progress of classical swine fever vaccine. Two key points for the control of classical swine fever have been put forward.%对我国的猪瘟流行的新特点进行了描述，详细分析了造成猪瘟疫苗免疫失败的6大原因，并且对疫苗的发展历史和研究进展进行了详细介绍，提出了猪瘟防控的两个关键环节为种猪群野毒感染的控制及有效的免疫接种。
Foucault's pendulum, a classical analog for the electron spin state
Linck, Rebecca A.
Spin has long been regarded as a fundamentally quantum phenomena that is incapable of being described classically. To bridge the gap and show that aspects of spin's quantum nature can be described classically, this work uses a classical Lagrangian based on the coupled oscillations of Foucault's pendulum as an analog for the electron spin state in an external magnetic field. With this analog it is possible to demonstrate that Foucault's pendulum not only serves as a basis for explaining geometric phase, but is also a basis for reproducing a broad range of behavior from Zeeman-like frequency splitting to precession of the spin state. By demonstrating that unmeasured electron spin states can be fully described in classical terms, this research opens the door to using the tools of classical physics to examine an inherently quantum phenomenon.
Proceedings Third International Workshop on Classical Logic and Computation
van Bakel, Steffen; Berger, Ulrich; 10.4204/EPTCS.47
2011-01-01
The fact that classical mathematical proofs of simply existential statements can be read as programs was established by Goedel and Kreisel half a century ago. But the possibility of extracting useful computational content from classical proofs was taken seriously only from the 1990s on when it was discovered that proof interpretations based on Goedel's and Kreisel's ideas can provide new nontrivial algorithms and numerical results, and the Curry-Howard correspondence can be extended to classical logic via programming concepts such as continuations and control operators. The workshop series "Classical Logic and Computation" aims to support a fruitful exchange of ideas between the various lines of research on computational aspects of classical logic. This volume contains the abstracts of the invited lectures and the accepted contributed papers of the third CL&C workshop which was held jointly with the workshop "Program Extraction and Constructive Mathematics" at the University of Brno in August 21-22, 2010,...
Classical and quantum dynamics from classical paths to path integrals
Dittrich, Walter
2017-01-01
Graduate students who wish to become familiar with advanced computational strategies in classical and quantum dynamics will find in this book both the fundamentals of a standard course and a detailed treatment of the time-dependent oscillator, Chern-Simons mechanics, the Maslov anomaly and the Berry phase, to name just a few topics. Well-chosen and detailed examples illustrate perturbation theory, canonical transformations and the action principle, and demonstrate the usage of path integrals. The fifth edition has been revised and enlarged to include chapters on quantum electrodynamics, in particular, Schwinger’s proper time method and the treatment of classical and quantum mechanics with Lie brackets and pseudocanonical transformations. It is shown that operator quantum electrodynamics can be equivalently described with c-numbers, as demonstrated by calculating the propagation function for an electron in a prescribed classical electromagnetic field.
Does classical liberalism imply democracy?
David Ellerman
2015-12-01
Full Text Available There is a fault line running through classical liberalism as to whether or not democratic self-governance is a necessary part of a liberal social order. The democratic and non-democratic strains of classical liberalism are both present today—particularly in the United States. Many contemporary libertarians and neo-Austrian economists represent the non-democratic strain in their promotion of non-democratic sovereign city-states (start-up cities or charter cities. We will take the late James M. Buchanan as a representative of the democratic strain of classical liberalism. Since the fundamental norm of classical liberalism is consent, we must start with the intellectual history of the voluntary slavery contract, the coverture marriage contract, and the voluntary non-democratic constitution (or pactum subjectionis. Next we recover the theory of inalienable rights that descends from the Reformation doctrine of the inalienability of conscience through the Enlightenment (e.g. Spinoza and Hutcheson in the abolitionist and democratic movements. Consent-based governments divide into those based on the subjects’ alienation of power to a sovereign and those based on the citizens’ delegation of power to representatives. Inalienable rights theory rules out that alienation in favor of delegation, so the citizens remain the ultimate principals and the form of government is democratic. Thus the argument concludes in agreement with Buchanan that the classical liberal endorsement of sovereign individuals acting in the marketplace generalizes to the joint action of individuals as the principals in their own organizations.
Classical approach in atomic physics
Solov'ev, E. A.
2011-12-01
The application of a classical approach to various quantum problems - the secular perturbation approach to quantization of a hydrogen atom in external fields and a helium atom, the adiabatic switching method for calculation of a semiclassical spectrum of a hydrogen atom in crossed electric and magnetic fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's approach to Stark problem, long-lived excited states of a helium atom discovered with the help of Poincaré section, inelastic transitions in slow and fast electron-atom and ion-atom collisions - is reviewed. Further, a classical representation in quantum theory is discussed. In this representation the quantum states are treated as an ensemble of classical states. This approach opens the way to an accurate description of the initial and final states in classical trajectory Monte Carlo (CTMC) method and a purely classical explanation of tunneling phenomenon. The general aspects of the structure of the semiclassical series such as renormgroup symmetry, criterion of accuracy and so on are reviewed as well.
Classical approach in atomic physics
Solov' ev, E.A. [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)
2011-12-15
The application of a classical approach to various quantum problems - the secular perturbation approach to quantization of a hydrogen atom in external fields and a helium atom, the adiabatic switching method for calculation of a semiclassical spectrum of a hydrogen atom in crossed electric and magnetic fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's approach to Stark problem, long-lived excited states of a helium atom discovered with the help of Poincare section, inelastic transitions in slow and fast electron-atom and ion-atom collisions - is reviewed. Further, a classical representation in quantum theory is discussed. In this representation the quantum states are treated as an ensemble of classical states. This approach opens the way to an accurate description of the initial and final states in classical trajectory Monte Carlo (CTMC) method and a purely classical explanation of tunneling phenomenon. The general aspects of the structure of the semiclassical series such as renormalization group symmetry, criterion of accuracy and so on are reviewed as well. (author)
No Return to Classical Reality
Jennings, David
2015-01-01
At a fundamental level, the classical picture of the world is dead, and has been dead now for almost a century. Pinning down exactly which quantum phenomena are responsible for this has proved to be a tricky and controversial question, but a lot of progress has been made in the past few decades. We now have a range of precise statements showing that whatever the ultimate laws of Nature are, they cannot be classical. In this article, we review results on the fundamental phenomena of quantum theory that cannot be understood in classical terms. We proceed by first granting quite a broad notion of classicality, describe a range of quantum phenomena (such as randomness, discreteness, the indistinguishability of states, measurement-uncertainty, measurement-disturbance, complementarity, noncommutativity, interference, the no-cloning theorem, and the collapse of the wave-packet) that do fall under its liberal scope, and then finally describe some aspects of quantum physics that can never admit a classical understandi...
Malpetti, Daniele; Roscilde, Tommaso
2017-02-01
The mean-field approximation is at the heart of our understanding of complex systems, despite its fundamental limitation of completely neglecting correlations between the elementary constituents. In a recent work [Phys. Rev. Lett. 117, 130401 (2016), 10.1103/PhysRevLett.117.130401], we have shown that in quantum many-body systems at finite temperature, two-point correlations can be formally separated into a thermal part and a quantum part and that quantum correlations are generically found to decay exponentially at finite temperature, with a characteristic, temperature-dependent quantum coherence length. The existence of these two different forms of correlation in quantum many-body systems suggests the possibility of formulating an approximation, which affects quantum correlations only, without preventing the correct description of classical fluctuations at all length scales. Focusing on lattice boson and quantum Ising models, we make use of the path-integral formulation of quantum statistical mechanics to introduce such an approximation, which we dub quantum mean-field (QMF) approach, and which can be readily generalized to a cluster form (cluster QMF or cQMF). The cQMF approximation reduces to cluster mean-field theory at T =0 , while at any finite temperature it produces a family of systematically improved, semi-classical approximations to the quantum statistical mechanics of the lattice theory at hand. Contrary to standard MF approximations, the correct nature of thermal critical phenomena is captured by any cluster size. In the two exemplary cases of the two-dimensional quantum Ising model and of two-dimensional quantum rotors, we study systematically the convergence of the cQMF approximation towards the exact result, and show that the convergence is typically linear or sublinear in the boundary-to-bulk ratio of the clusters as T →0 , while it becomes faster than linear as T grows. These results pave the way towards the development of semiclassical numerical
焦宝
2016-01-01
The view of the literature history of one hundred years was constructed centering on ver-nacular literature put forward by HU Shi and others,civilian literature,etc. Through systematically clarifying the view of the literature history put forward by HU Shi,we can find that many facts of the literary history were distorted or hidden under the control of the view of the literary history,which did not take literature self as the purpose. The academic research of MU Zhai has reflected on the histori-cal view,made a breakthrough,restored the truth of the history of literature,and become a hot topic in recent years. With the aid of the innovation of methodology brought by scholars such as MU Zhai, the transfer of academic fashion of the times may be achieved. The change which MU Zhai’s aca-demic thoughts success in disengaging from the view of the literature history of one hundred years has important significance.%百年来的文学史观是以胡适等人提出的白话文学、平民文学等为核心建构起来的。对胡适文学史观进行系统梳理可以发现，在这一文学史观支配下，扭曲和遮蔽了许多文学史实。这一史观本身并非是以文学本身为旨归的。木斋的学术研究对这一史观进行反思，实现了突破，还原了文学史的真实，成为近年来学界讨论的一个学术热点。借助木斋以及宇文所安等学者带来的方法论革新，有望实现时代学术风尚的转移。木斋的学术思想从百年文学史观中脱离出来并实现转向，具有重要意义。
李光燕; 王德群; 方士英; 徐茂红
2014-01-01
Aucklandia lappa Decne was first recorded in the Sheng nong ben cao jing (Shennong's Classic ofMateria Medica).Through the textual research of herbal literature,it was found that the costus root in the Sheng nong ben cao jing perhaps was not the plant of Aucklandia lappa Decne of Compositae,but the eaglewood or Lignum Aquilasria Resinatum based on the comprehensive judgment of shape,taste,nature,and function etc.In the Sheng nong ben cao jing,it only includes costus root without the title of eaglewood,and Tao Hongjing recorded both herbs together in his Ming yi bie lu (Supplementary Records of Celebrated Physicians),which became a foreshadow of misunderstanding of the later generations.Beginning from the Tang ben cao (Materia Medica of the Tang Dynasty),the costus root was considered as the plant of Auckiandia lappa Decne from the Compostae with its profound influence until now.%中药木香最早记载于《神农本草经》.通过考察多种本草文献,发现《神农本草经》中的木香可能不是现代菊科木香类植物,而是沉香,因为从形态、气味、功效等方面综合判断,沉香与《本神农草经》中的木香相吻合.《神农本草经》中只有“木香”,而无“沉香”,陶弘景将“木香”与“沉香”一并记载于《名医别录》中,为后人的误识埋下了伏笔.自《唐本草》始认为“木香”主要为菊科的木香类草本植物,这种认识一直影响至今.马兜铃科藤本青木香在《唐本草》和《本草图经》等本草著作的“木香”条中均有记载,但不做“木香”药用的主流.
Population in the classic economics
Adnan Doğruyol
2013-02-01
Full Text Available Growth subject in economics is an important factor of development. Classic economics ecole indicates the population as main variable which tender of growth. On the other hand T. R. Malthus is known as economist who regards population as a problem and brings up it among the classical economists. However, Adam Smith is an intellectual who discussed population problem earlier on the classic economics theory. According to Adam Smith one of the main factors that realise the growth is labour. In addition to population made it established. The aim of this study is analyzing the mental relationship between Malthus whose name has been identified with relation between population-growth and Smith who discussed this subject first time but put it off on process of theorisation.
Classical issues in electroweak baryogenesis
Smit, J; Smit, Jan; Tranberg, Anders
2004-01-01
In one scenario of baryogenesis, the matter-antimatter asymmetry was generated in the early universe during a cold electroweak transition. We model this transition by changing the sign of the effective mass-squared parameter of the Higgs field from positive to negative. The resulting `tachyonic' instability leads to a rapid growth of occupation numbers, such that a classical approximation can be made in computing subsequent developments in real time. We solve the classical equations of motion in the SU(2)-Higgs model under the influence of effective CP-violation. The resulting baryon asymmetry follows from the generated Chern-Simons number using the anomaly equation. The `classical' difficulties with lattice implementations of these observables are avoided here because the fields are smooth on the lattice scale.
Overview of Classical Swine Fever (Hog Cholera, Classical Swine fever)
Classical swine fever is a contagious often fatal disease of pigs clinically characterized by high body temperature, lethargy, yellowish diarrhea, vomits and purple skin discoloration of ears, lower abdomen and legs. It was first described in the early 19th century in the USA. Later, a condition i...
Optimum Onager: The Classical Mechanics of a Classical Siege Engine
Denny, Mark
2009-01-01
The onager is a throwing weapon of classical antiquity, familiar to both the ancient Greeks and Romans. Here we analyze the dynamics of onager operation and derive the optimum angle for launching a projectile to its maximum range. There is plenty of scope for further considerations about increasing onager range, and so by thinking about how this…
Classical planning and causal implicatures
Blackburn, Patrick Rowan; Benotti, Luciana
to generate clarification requests"; as a result we can model task-oriented dialogue as an interactive process locally structured by negotiation of the underlying task. We give several examples of Frolog-human dialog, discuss the limitations imposed by the classical planning paradigm, and indicate......In this paper we motivate and describe a dialogue manager (called Frolog) which uses classical planning to infer causal implicatures. A causal implicature is a type of Gricean relation implicature, a highly context dependent form of inference. As we shall see, causal implicatures are important...
Quantum teleportation without classical channel
Al Amri, M.; Li, Zheng-Hong; Zubairy, M. Suhail
2016-11-01
For the first time, we show how quantum teleportation can be achieved without the assistance of classical channels. Our protocol does not need any pre-established entangled photon pairs beforehand. Just by utilizing quantum Zeno effect and couterfactual communication idea, we can achieve two goals; entangling a photon and an atom and also disentangling them by non-local interaction. Information is completely transferred from atom to photon with controllable disentanglement processes. More importantly, there is no need to confirm teleportation results via classical channels.
Classical planning and causal implicatures
Blackburn, Patrick Rowan; Benotti, Luciana
In this paper we motivate and describe a dialogue manager (called Frolog) which uses classical planning to infer causal implicatures. A causal implicature is a type of Gricean relation implicature, a highly context dependent form of inference. As we shall see, causal implicatures are important...... to generate clarification requests"; as a result we can model task-oriented dialogue as an interactive process locally structured by negotiation of the underlying task. We give several examples of Frolog-human dialog, discuss the limitations imposed by the classical planning paradigm, and indicate...
Classical Dynamics of Quantum Entanglement
Casati, Giulio; Reslen, Jose
2011-01-01
We numerically analyze the dynamical generation of quantum entanglement in a system of 2 interacting particles, started in a coherent separable state, for decreasing values of $\\hbar$. As $\\hbar\\to 0$ the entanglement entropy, computed at any finite time, converges to a finite nonzero value, that can be reproduced by purely classical computations. The limiting classical law which rules the time dependence of entropy is different in the integrable and in the chaotic case, and its general qualitative and quantitative features may be explained by simple heuristic arguments.
Comparing classical and quantum equilibration
Malabarba, Artur S L; Short, Anthony J
2016-01-01
By using a physically-relevant and theory independent definition of measurement-based equilibration, we show quantitatively that equilibration is easier for quantum systems than for classical systems, in the situation where the initial state of the system is completely known (pure state). This shows that quantum equilibration is a fundamental, nigh unavoidable, aspect of physical systems, while classical equilibration relies on experimental ignorance. When the state is not completely known, a mixed state, this framework also shows quantum equilibration requires weaker conditions.
A Classical Solution of Massive Yang-Mills Fields
Mogami, Tsuguo
2016-01-01
Recent researches on the solution of Schwinger-Dyson equations, as well as lattice simulations of pure QCD, suggest that the gluon propagator is massive. In this letter, we assume that the classical counterpart of this massive gluon field may be represented with the equation of motion for Yang-Mills theory with a mass term added. A new classical solution is given for this equation. It is discussed that this solution may have some role in confinement.
Relative Clauses in Classical Nahuatl
Langacker, Ronald W.
1975-01-01
Jane Rosenthal's paper on relative clauses in Classical Nahuatl is discussed, and it is argued that she misses an important generalization. An alternative analysis to a class of relative pronouns and new rules for the distribution of relative pronouns are proposed. (SC)
On Classical and Quantum Cryptography
Volovich, I V; Volovich, Ya.I.
2001-01-01
Lectures on classical and quantum cryptography. Contents: Private key cryptosystems. Elements of number theory. Public key cryptography and RSA cryptosystem. Shannon`s entropy and mutual information. Entropic uncertainty relations. The no cloning theorem. The BB84 quantum cryptographic protocol. Security proofs. Bell`s theorem. The EPRBE quantum cryptographic protocol.
On classical and quantum liftings
Accardi, L; Kossakowski, A; Matsuoka, T; Ohya, M
2011-01-01
We analyze the procedure of lifting in classical stochastic and quantum systems. It enables one to `lift' a state of a system into a state of `system+reservoir'. This procedure is important both in quantum information theory and the theory of open systems. We illustrate the general theory of liftings by a particular class related to so called circulant states.
Relative Clauses in Classical Nahuatl
Langacker, Ronald W.
1975-01-01
Jane Rosenthal's paper on relative clauses in Classical Nahuatl is discussed, and it is argued that she misses an important generalization. An alternative analysis to a class of relative pronouns and new rules for the distribution of relative pronouns are proposed. (SC)
CLASSIC APPROACH TO BUSINESS COACHING
Żukowska, Joanna
2011-01-01
The purpose of this paper is to present business coaching in a classical way. An overview of coaching definitions will be provided. Attention will be drawn to coaching components and varieties. Moreover, a brief description of coach competences and tools supporting their work will be offered. Joanna Żukowska
Classical and quantum Coulomb crystals
Bonitz, M; Baumgartner, H; Henning, C; Filinov, A; Block, D; Arp, O; Piel, A; Kading, S; Ivanov, Y; Melzer, A; Fehske, H; Filinov, V
2008-01-01
Strong correlation effects in classical and quantum plasmas are discussed. In particular, Coulomb (Wigner) crystallization phenomena are reviewed focusing on one-component non-neutral plasmas in traps and on macroscopic two-component neutral plasmas. The conditions for crystal formation in terms of critical values of the coupling parameters and the distance fluctuations and the phase diagram of Coulomb crystals are discussed.
Teaching Classical Mechanics Using Smartphones
Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad
2013-01-01
A number of articles published in this column have dealt with topics in classical mechanics. This note describes some additional examples employing a smartphone and the new software iMecaProf. Steve Jobs presented the iPhone as "perfect for gaming." Thanks to its microsensors connected in real time to the numerical world, physics…
Classical Syllogisms in Logic Teaching
Øhrstrøm, Peter; Sandborg-Petersen, Ulrik; Thorvaldsen, Steinar
2013-01-01
This paper focuses on the challenges of introducing classical syllogisms in university courses in elementary logic and human reasoning. Using a program written in Prolog+CG, some empirical studies have been carried out involving three groups of students in Denmark; one group of philosophy student...
Teaching Classical Mechanics Using Smartphones
Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad
2013-01-01
A number of articles published in this column have dealt with topics in classical mechanics. This note describes some additional examples employing a smartphone and the new software iMecaProf. Steve Jobs presented the iPhone as "perfect for gaming." Thanks to its microsensors connected in real time to the numerical world, physics…
Quantum proofs for classical theorems
Drucker, A.; de Wolf, R.
2011-01-01
Alongside the development of quantum algorithms and quantum complexity theory in recent years, quantum techniques have also proved instrumental in obtaining results in diverse classical (non-quantum) areas, such as coding theory, communication complexity, and polynomial approximations. In this paper
Supersymmetric classical mechanics: free case
Rodrigues, R. de Lima [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]|[Paraiba Univ., Cajazeiras, PB (Brazil). Dept. de Ciencias Exatas e da Natureza]. E-mail: rafael@cfp.ufpb.br; Almeida, W. Pires de [Paraiba Univ., Cajazeiras, PB (Brazil). Dept. de Ciencias Exatas e da Natureza; Fonseca Neto, I. [Paraiba Univ., Campina Grande, PB (Brazil). Dept. de Fisica
2001-06-01
We present a review work on Supersymmetric Classical Mechanics in the context of a Lagrangian formalism, with N = 1-supersymmetry. We show that the N = 1 supersymmetry does not allow the introduction of a potencial energy term depending on a single commuting supercoordinate, {phi}(t;{theta}). (author)
Classical and molecular genetic mapping
A brief history of classical genetic mapping in soybean [Glycine max (L.) Merr.] is described. Detailed descriptions are given of the development of molecular genetic linkage maps based upon various types of DNA markers Like many plant and animal species, the first molecular map of soybean was bas...
Minimum signals in classical physics
邓文基; 许基桓; 刘平
2003-01-01
The bandwidth theorem for Fourier analysis on any time-dependent classical signal is shown using the operator approach to quantum mechanics. Following discussions about squeezed states in quantum optics, the problem of minimum signals presented by a single quantity and its squeezing is proposed. It is generally proved that all such minimum signals, squeezed or not, must be real Gaussian functions of time.
Classical Music as Enforced Utopia
Leech-Wilkinson, Daniel
2016-01-01
In classical music composition, whatever thematic or harmonic conflicts may be engineered along the way, everything always turns out for the best. Similar utopian thinking underlies performance: performers see their job as faithfully carrying out their master's (the composer's) wishes. The more perfectly they represent them, the happier the…
No return to classical reality
Jennings, David; Leifer, Matthew
2016-01-01
At a fundamental level, the classical picture of the world is dead, and has been dead now for almost a century. Pinning down exactly which quantum phenomena are responsible for this has proved to be a tricky and controversial question, but a lot of progress has been made in the past few decades. We now have a range of precise statements showing that whatever the ultimate laws of nature are, they cannot be classical. In this article, we review results on the fundamental phenomena of quantum theory that cannot be understood in classical terms. We proceed by first granting quite a broad notion of classicality, describe a range of quantum phenomena (such as randomness, discreteness, the indistinguishability of states, measurement-uncertainty, measurement-disturbance, complementarity, non-commutativity, interference, the no-cloning theorem and the collapse of the wave-packet) that do fall under its liberal scope, and then finally describe some aspects of quantum physics that can never admit a classical understanding - the intrinsically quantum mechanical aspects of nature. The most famous of these is Bell's theorem, but we also review two more recent results in this area. Firstly, Hardy's theorem shows that even a finite-dimensional quantum system must contain an infinite amount of information, and secondly, the Pusey-Barrett-Rudolph theorem shows that the wave function must be an objective property of an individual quantum system. Besides being of foundational interest, results of this sort now find surprising practical applications in areas such as quantum information science and the simulation of quantum systems.
Does classical mechanics always adequately describe "classical physical reality"
Shemi-zadeh, V E
2002-01-01
The article is dedicated to discussion of irreversibility and foundation of statistical mechanics "from the first principles". Taking into account infinitesimal and, as it seems, neglectful for classical mechanics fluctuations of the physical vacuum, makes a deterministic motion of unstable dynamic systems is broken ("spontaneous determinism breaking", "spontaneous stochastization"). Vacuum fluctuations play part of the trigger, starting the powerful mechanism of exponent instability. The motion of the dynamic systems becomes irreversible and stochastic. Classical mechanics turns out to be applicable only for a small class of stable dynamic systems with zero Kolmogorov-Sinay entropy $h=0$. For alternative "Stochastic mechanics" there are corresponding equations of motion and Master Equation, describing irreversible evolution of the initial distribution function to equilibrium state.
程佳佳
2016-01-01
The story of Greek mythology is the source of western literature. Classical western literature represented by Greek mythology is not only rich in content, but also contains unusual imagination. As a result, many western writers have tried to draw inspiration and nutrition through Greek mythology, so as to bring a richer levels and aesthetic appeal into their works. This paper combined with the characteristics of the western classical literature, explained the archetype and influence of Greek mythology in classical western literature, and discussed its influence.%希腊神话故事是西方文学的源头，以希腊神话为代表的古典西方文学不仅具有丰富的内容，而且想象异乎寻常的奇特。因此，很多西方文学创作者都试图通过希腊神话故事，汲取创作灵感与营养，为其作品带来更丰富的层次与审美魅力。本文结合西方古典文学的特性，对古典西方文学中的希腊神话原型进行了阐释，并就其在西方文学中的影响力进行了探讨。
Why Can We Copy Classical Information?
SHEN Yao; HAO Liang; LONG Gui-Lu
2011-01-01
It is pointed out that the noncloning theorem in quantum mechanics also holds for unknown state in linear classical physics. The apparent capability of copying of a classical state is essentially the capability of perfect measurement in classical physics. The difference in copying between quantum and classical physics is the difference in measurement between the two theories. A classical copying process is the combined action of measurement of an unknown state and the preparation of this state onto another system. Hence perfect measurability in classical physics enables the copying of a classical state.
RAACFDb: Rheumatoid arthritis ayurvedic classical formulations database.
Mohamed Thoufic Ali, A M; Agrawal, Aakash; Sajitha Lulu, S; Mohana Priya, A; Vino, S
2017-02-02
In the past years, the treatment of rheumatoid arthritis (RA) has undergone remarkable changes in all therapeutic modes. The present newfangled care in clinical research is to determine and to pick a new track for better treatment options for RA. Recent ethnopharmacological investigations revealed that traditional herbal remedies are the most preferred modality of complementary and alternative medicine (CAM). However, several ayurvedic modes of treatments and formulations for RA are not much studied and documented from Indian traditional system of medicine. Therefore, this directed us to develop an integrated database, RAACFDb (acronym: Rheumatoid Arthritis Ayurvedic Classical Formulations Database) by consolidating data from the repository of Vedic Samhita - The Ayurveda to retrieve the available formulations information easily. Literature data was gathered using several search engines and from ayurvedic practitioners for loading information in the database. In order to represent the collected information about classical ayurvedic formulations, an integrated database is constructed and implemented on a MySQL and PHP back-end. The database is supported by describing all the ayurvedic classical formulations for the treatment rheumatoid arthritis. It includes composition, usage, plant parts used, active ingredients present in the composition and their structures. The prime objective is to locate ayurvedic formulations proven to be quite successful and highly effective among the patients with reduced side effects. The database (freely available at www.beta.vit.ac.in/raacfdb/index.html) hopefully enables easy access for clinical researchers and students to discover novel leads with reduced side effects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
A Walk Through an American Classic
Emma Gage
2012-12-01
Full Text Available The music of Walt Disney’s classic films was written by a number of hand-picked composers who, working with Disney, ingeniously crafted the music to fit animation and bring musical inspiration to the homes of viewers leaving America and the world with a beloved legacy. Though Walt Disney was a cartoonist and not a musician, music was given a distinct, almost central, role in the creation of his cartoons. Special techniques such as Mickey-mousing or the click track were developed by composers and used to synchronize this music and animation. These processes really began with Disney and have formed the basis for all music synchronized to cartoon animation. From the very beginning with Mickey Mouse, to The Silly Symphonies, to the beloved classic Disney movies music has been an ever-present and developing center. Walt Disney, though not a composer himself, hired a number of key composers from which we have many cherished melodies. Unlike most other cartoons Disney’s were focused on using music of the classical style rather than the popular style. The music from a number of classical composers was used or drawn upon as a model. Disney had a special purpose for the music in his animated films. Most of his films contained a story other than the music, but his movie Fantasia really seeks to find the purpose music itself has with visual interpretation. College students have done research on these ideas of simply listening to music or listening while seeing an image. All of Disney’s animated films would not be the classics they are without the music that holds them together. Disney music has become recognized as its own individual art form. It has inspired America to dream and to think more deeply than realized. Walt Disney’s indirect effect on music history may be considered a stretch, but there is no doubt that the music developed through Disney Bros. has left an inspiration on the hearts of Americans.
Teaching Classical Mechanics using Smartphones
Chevrier, Joel; Ledenmat, Simon; Bsiesy, Ahmad
2012-01-01
Using a personal computer and a smartphone, iMecaProf is a software that provides a complete teaching environment for practicals associated to a Classical Mechanics course. iMecaProf proposes a visual, real time and interactive representation of data transmitted by a smartphone using the formalism of Classical Mechanics. Using smartphones is more than using a set of sensors. iMecaProf shows students that important concepts of physics they here learn, are necessary to control daily life smartphone operations. This is practical introduction to mechanical microsensors that are nowadays a key technology in advanced trajectory control. First version of iMecaProf can be freely downloaded. It will be tested this academic year in Universit\\'e Joseph Fourier (Grenoble, France)
Classical Corrections in String Cosmology
Brustein, Ram; Brustein, Ram; Madden, Richard
1999-01-01
An important element in a model of non-singular string cosmology is a phase in which classical corrections saturate the growth of curvature in a deSitter-like phase with a linearly growing dilaton (an `algebraic fixed point'). As the form of the classical corrections is not well known, here we look for evidence, based on a suggested symmetry of the action, scale factor duality and on conformal field theory considerations, that they can produce this saturation. It has previously been observed that imposing scale factor duality on the $O(\\alpha')$ corrections is not compatible with fixed point behavior. Here we present arguments that these problems persist to all orders in $\\alpha'$. We also present evidence for the form of a solution to the equations of motion using conformal perturbation theory, examine its implications for the form of the effective action and find novel fixed point structure.
Classical corrections in string cosmology
Brustein, Ram; Madden, Richard
1999-07-01
An important element in a model of non-singular string cosmology is a phase in which classical corrections saturate the growth of curvature in a deSitter-like phase with a linearly growing dilaton (an `algebraic fixed point'). As the form of the classical corrections is not well known, here we look for evidence, based on a suggested symmetry of the action, scale factor duality and on conformal field theory considerations, that they can produce this saturation. It has previously been observed that imposing scale factor duality on the O(alpha') corrections is not compatible with fixed point behavior. Here we present arguments that these problems persist to all orders in alpha'. We also present evidence for the form of a solution to the equations of motion using conformal perturbation theory, examine its implications for the form of the effective action and find novel fixed point structure.
Quantum Models of Classical World
Petr Hájíček
2013-02-01
Full Text Available This paper is a review of our recent work on three notorious problems of non-relativistic quantum mechanics: realist interpretation, quantum theory of classical properties, and the problem of quantum measurement. A considerable progress has been achieved, based on four distinct new ideas. First, objective properties are associated with states rather than with values of observables. Second, all classical properties are selected properties of certain high entropy quantum states of macroscopic systems. Third, registration of a quantum system is strongly disturbed by systems of the same type in the environment. Fourth, detectors must be distinguished from ancillas and the states of registered systems are partially dissipated and lost in the detectors. The paper has two aims: a clear explanation of all new results and a coherent and contradiction-free account of the whole quantum mechanics including all necessary changes of its current textbook version.
Classical Equations for Quantum Systems
Gell-Mann, Murray; Gell-Mann, Murray; Hartle, James B.
1993-01-01
The origin of the phenomenological deterministic laws that approximately govern the quasiclassical domain of familiar experience is considered in the context of the quantum mechanics of closed systems such as the universe as a whole. We investigate the requirements for coarse grainings to yield decoherent sets of histories that are quasiclassical, i.e. such that the individual histories obey, with high probability, effective classical equations of motion interrupted continually by small fluctuations and occasionally by large ones. We discuss these requirements generally but study them specifically for coarse grainings of the type that follows a distinguished subset of a complete set of variables while ignoring the rest. More coarse graining is needed to achieve decoherence than would be suggested by naive arguments based on the uncertainty principle. Even coarser graining is required in the distinguished variables for them to have the necessary inertia to approach classical predictability in the presence of t...
From classical to quantum physics
Stehle, Philip
2017-01-01
Suitable for lay readers as well as students, this absorbing survey explores the twentieth-century transition from classical to quantum physics. Author Philip Stehle traces the shift in the scientific worldview from the work of Galileo, Newton, and Darwin to the modern-day achievements of Max Planck, Albert Einstein, Ernest Rutherford, Niels Bohr, and others of their generation. His insightful overview examines not only the history of quantum physics but also the ways that progress in the discipline changed our understanding of the physical world and forces of nature. This chronicle of the second revolution in the physical sciences conveys the excitement and suspense that new developments produced in the scientific community. The narrative ranges from the classical physics of the seventeenth-century to the emergence of quantum mechanics with the entrance of the electron, the rise of relativity theory, the development of atomic theory, and the recognition of wave-particle duality. Relevant mathematical details...
Stress theory for classical fields
Kupferman, Raz; Olami, Elihu; Segev, Reuven
2017-01-01
Classical field theories together with the Lagrangian and Eulerian approaches to continuum mechanics are embraced under a geometric setting of a fiber bundle. The base manifold can be either the body manifold of continuum mechanics, space manifold, or space-time. Differentiable sections of the fiber bundle represent configurations of the system and the configuration space containing them is given the structure of an infinite dimensional manifold. Elements of the cotangent bundle of the config...
Potential Theory in Classical Electrodynamics
Engelhardt, Wolfgang
2012-01-01
In Maxwell's classical theory of electrodynamics the fields are frequently expressed by potentials in order to facilitate the solution of the first order system of equations. This method obscures, however, that there exists an inconsistency between Faraday's law of induction and Maxwell's flux law. As a consequence of this internal contradiction there is neither gauge invariance, nor exist unique solutions in general. It is also demonstrated that inhomogeneous wave equations cannot be solved by retarded integrals.
Psoriasis: classical and emerging comorbidities*
de Oliveira, Maria de Fátima Santos Paim; Rocha, Bruno de Oliveira; Duarte, Gleison Vieira
2015-01-01
Psoriasis is a chronic inflammatory systemic disease. Evidence shows an association of psoriasis with arthritis, depression, inflammatory bowel disease and cardiovascular diseases. Recently, several other comorbid conditions have been proposed as related to the chronic inflammatory status of psoriasis. The understanding of these conditions and their treatments will certainly lead to better management of the disease. The present article aims to synthesize the knowledge in the literature about the classical and emerging comorbidities related to psoriasis. PMID:25672294
Quantum manifolds with classical limit
Hohmann, Manuel; Wohlfarth, Mattias N R
2008-01-01
We propose a mathematical model of quantum spacetime as an infinite-dimensional manifold locally homeomorphic to an appropriate Schwartz space. This extends and unifies both the standard function space construction of quantum mechanics and the manifold structure of spacetime. In this picture we demonstrate that classical spacetime emerges as a finite-dimensional manifold through the topological identification of all quantum points with identical position expectation value. We speculate on the possible relevance of this geometry to quantum field theory and gravity.
Strong Analog Classical Simulation of Coherent Quantum Dynamics
Wang, Dong-Sheng
2017-02-01
A strong analog classical simulation of general quantum evolution is proposed, which serves as a novel scheme in quantum computation and simulation. The scheme employs the approach of geometric quantum mechanics and quantum informational technique of quantum tomography, which applies broadly to cases of mixed states, nonunitary evolution, and infinite dimensional systems. The simulation provides an intriguing classical picture to probe quantum phenomena, namely, a coherent quantum dynamics can be viewed as a globally constrained classical Hamiltonian dynamics of a collection of coupled particles or strings. Efficiency analysis reveals a fundamental difference between the locality in real space and locality in Hilbert space, the latter enables efficient strong analog classical simulations. Examples are also studied to highlight the differences and gaps among various simulation methods. Funding support from NSERC of Canada and a research fellowship at Department of Physics and Astronomy, University of British Columbia are acknowledged
Quantum spectra and classical periodic orbit in the cubic billiard
Dehua Wang; Yongjiang Yu; Shenglu Lin
2006-01-01
Quantum billiards have attracted much interest in many fields. People have made a lot of researches on the two-dimensional (2D) billiard systems. Contrary to the 2D billiard, due to the complication of its classical periodic orbits, no one has studied the correspondence between the quantum spectra and the classical orbits of the three-dimensional (3D) billiards. Taking the cubic billiard as an example, using the periodic orbit theory, we find the periodic orbit of the cubic billiard and study the correspondence between the quantum spectra and the length of the classical orbits in 3D system. The Fourier transformed spectrum of this system has allowed direct comparison between peaks in such plot and the length of the periodic orbits, which verifies the correctness of the periodic orbit theory. This is another example showing that semiclassical method provides a bridge between quantum and classical mechanics.
Rindler Photons and Classical Radiation
Díaz, D E
2001-01-01
We describe the quantum and classical radiation by a uniformly accelerating point source in terms of the elementary processes of absorption and emission of Rindler scalar photons of the Fulling-Davies-Unruh bath observed by a co-accelerating observer.To this end we compute the emission rate by a DeWitt detector of a Minkowski scalar field particle with defined transverse momentum per unit of proper time of the source and we show that it corresponds to the induced absorption or spontaneous and induced emission of Rindler photons from the thermal bath. We then take what could be called the inert limit of the DeWitt detector by considering the limit of zero gap energy. As suggested by DeWitt, we identify in this limit the detector with a classical point source and verify the consistency of our computation with the classical result. Finally, we study the behavior of the emission rate in D space-time dimensions in connection with the so called apparent statistics inversion.
Classical theory of atomic collisions - The first hundred years
Grujić, Petar V.
2012-05-01
Classical calculations of the atomic processes started in 1911 with famous Rutherford's evaluation of the differential cross section for α particles scattered on foil atoms [1]. The success of these calculations was soon overshadowed by the rise of Quantum Mechanics in 1925 and its triumphal success in describing processes at the atomic and subatomic levels. It was generally recognized that the classical approach should be inadequate and it was neglected until 1953, when the famous paper by Gregory Wannier appeared, in which the threshold law for the single ionization cross section behaviour by electron impact was derived. All later calculations and experimental studies confirmed the law derived by purely classical theory. The next step was taken by Ian Percival and collaborators in 60s, who developed a general classical three-body computer code, which was used by many researchers in evaluating various atomic processes like ionization, excitation, detachment, dissociation, etc. Another approach was pursued by Michal Gryzinski from Warsaw, who started a far reaching programme for treating atomic particles and processes as purely classical objects [2]. Though often criticized for overestimating the domain of the classical theory, results of his group were able to match many experimental data. Belgrade group was pursuing the classical approach using both analytical and numerical calculations, studying a number of atomic collisions, in particular near-threshold processes. Riga group, lead by Modris Gailitis [3], contributed considerably to the field, as it was done by Valentin Ostrovsky and coworkers from Sanct Petersbourg, who developed powerful analytical methods within purely classical mechanics [4]. We shall make an overview of these approaches and show some of the remarkable results, which were subsequently confirmed by semiclassical and quantum mechanical calculations, as well as by the experimental evidence. Finally we discuss the theoretical and
Quantum-Classical Correspondence: Dynamical Quantization and the Classical Limit
Turner, L [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)
2004-11-12
In only 150 pages, not counting appendices, references, or the index, this book is one author's perspective of the massive theoretical and philosophical hurdles in the no-man's-land separating the classical and quantum domains of physics. It ends with him emphasizing his own theoretical contribution to this area. In his own words, he has attempted to answer: 1. How can we obtain the quantum dynamics of open systems initially described by the equations of motion of classical physics (quantization process) 2. How can we retrieve classical dynamics from the quantum mechanical equations of motion by means of a classical limiting process (dequantization process). However, this monograph seems overly ambitious. Although the publisher's description refers to this book as an accessible entre, we find that this author scrambles too hastily over the peaks of information that are contained in his large collection of 272 references. Introductory motivating discussions are lacking. Profound ideas are glossed over superficially and shoddily. Equations morph. But no new convincing understanding of the physical world results. The author takes the viewpoint that physical systems are always in interaction with their environment and are thus not isolated and, therefore, not Hamiltonian. This impels him to produce a method of quantization of these stochastic systems without the need of a Hamiltonian. He also has interest in obtaining the classical limit of the quantized results. However, this reviewer does not understand why one needs to consider open systems to understand quantum-classical correspondence. The author demonstrates his method using various examples of the Smoluchowski form of the Fokker--Planck equation. He then renders these equations in a Wigner representation, uses what he terms an infinitesimality condition, and associates with a constant having the dimensions of an action. He thereby claims to develop master equations, such as the Caldeira
Quantum Transitions Between Classical Histories: Bouncing Cosmologies
Hartle, James
2015-01-01
In a quantum theory of gravity spacetime behaves classically when quantum probabilities are high for histories of geometry and field that are correlated in time by the Einstein equation. Probabilities follow from the quantum state. This quantum perspective on classicality has important implications: (a) Classical histories are generally available only in limited patches of the configuration space on which the state lives. (b) In a given patch states generally predict relative probabilities for an ensemble of possible classical histories. (c) In between patches classical predictability breaks down and is replaced by quantum evolution connecting classical histories in different patches. (d) Classical predictability can break down on scales well below the Planck scale, and with no breakdown in the classical equations of motion. We support and illustrate (a)-(d) by calculating the quantum transition across the de Sitter like throat connecting asymptotically classical, inflating histories in the no-boundary quantu...
Classical and quantum dynamics from classical paths to path integrals
Dittrich, Walter
2016-01-01
Graduate students who want to become familiar with advanced computational strategies in classical and quantum dynamics will find here both the fundamentals of a standard course and a detailed treatment of the time-dependent oscillator, Chern-Simons mechanics, the Maslov anomaly and the Berry phase, to name a few. Well-chosen and detailed examples illustrate the perturbation theory, canonical transformations, the action principle and demonstrate the usage of path integrals. This new edition has been revised and enlarged with chapters on quantum electrodynamics, high energy physics, Green’s functions and strong interaction.
Intuitionism vs. classicism a mathematical attack on classical logic
Haverkamp, Nick
2015-01-01
In the early twentieth century, the Dutch mathematician L.E.J. Brouwer launched a powerful attack on the prevailing mathematical methods and theories. He developed a new kind of constructive mathematics, called intuitionism, which seems to allow for a rigorous refutation of widely accepted mathematical assumptions including fundamental principles of classical logic. Following an intense mathematical debate esp. in the 1920s, Brouwer's revolutionary criticism became a central philosophical concern in the 1970s, when Michael Dummett tried to substantiate it with meaning-theoretic considerations.
The Relation between Classical and Quantum Electrodynamics
Mario Bacelar Valente
2011-01-01
Full Text Available Quantum electrodynamics presents intrinsic limitations in the description of physical processes that make it impossible to recover from it the type of description we have in classical electrodynamics. Hence one cannot consider classical electrodynamics as reducing to quantum electrodynamics and being recovered from it by some sort of limiting procedure. Quantum electrodynamics has to be seen not as an more fundamental theory, but as an upgrade of classical electrodynamics, which permits an extension of classical theory to the description of phenomena that, while being related to the conceptual framework of the classical theory, cannot be addressed from the classical theory.
Ngo, N. H.; Tran, H.; Gamache, R. R.; Bermejo, D.; Domenech, J.-L.
2012-08-01
The modeling of the shape of H2O lines perturbed by N2 (and air) using the Keilson-Storer (KS) kernel for collision-induced velocity changes is revisited with classical molecular dynamics simulations (CMDS). The latter have been performed for a large number of molecules starting from intermolecular-potential surfaces. Contrary to the assumption made in a previous study [H. Tran, D. Bermejo, J.-L. Domenech, P. Joubert, R. R. Gamache, and J.-M. Hartmann, J. Quant. Spectrosc. Radiat. Transf. 108, 126 (2007)], 10.1016/j.jqsrt.2007.03.009, the results of these CMDS show that the velocity-orientation and -modulus changes statistically occur at the same time scale. This validates the use of a single memory parameter in the Keilson-Storer kernel to describe both the velocity-orientation and -modulus changes. The CMDS results also show that velocity- and rotational state-changing collisions are statistically partially correlated. A partially correlated speed-dependent Keilson-Storer model has thus been used to describe the line-shape. For this, the velocity changes KS kernel parameters have been directly determined from CMDS, while the speed-dependent broadening and shifting coefficients have been calculated with a semi-classical approach. Comparisons between calculated spectra and measurements of several lines of H2O broadened by N2 (and air) in the ν3 and 2ν1 + ν2 + ν3 bands for a wide range of pressure show very satisfactory agreement. The evolution of non-Voigt effects from Doppler to collisional regimes is also presented and discussed.
Classical Optics and its Applications
Mansuripur, Masud
2009-02-01
Preface; Introduction; 1. Abbe's sine condition; 2. Fourier optics; 3. Effect of polarization on diffraction in systems of high numerical aperture; 4. Gaussian beam optics; 5. Coherent and incoherent imaging; 6. First-order temporal coherence in classical optics; 7. The Van Cittert-Zernike theorem; 8. Partial polarization, Stokes parameters, and the Poincarè Sphere; 9. Second-order coherence and the Hanbury Brown - Twiss experiment; 10. What in the world are surface plasmons?; 11. Surface plasmon polaritons on metallic surfaces; 12. The Faraday effecy; 13. The magneto-optical Kerr effect; 14. The Sagnac interferometer; 15. Fabry-Perot etalons in polarized light; 16. The Ewald-Oseen extinction theorem; 17. Reciprocity in classical Linear optics; 18. Optical pulse compression; 19. The uncertainty principle in classical optics; 20. Omni-directional dielectric mirrors; 21. Optical vortices; 22. Geometric-optical rays, Poynting's vector, and field momenta; 23. Doppler shift, stellar aberration, and convection of light by moving Media; 24. Diffraction gratings; 25. Diffractive optical elements; 26. The talbot effect; 27. Some quirks of total internal reflection; 28. Evanescent coupling; 29. Internal and external conical refraction; 30. Transmission of light through small elliptical apertures; 31. The method of Fox and Li; 32. The beam propagation method; 33. Launching light into a Fiber; 34. The optics of demiconductor fiode Laser; 35. Michelson's dtellar interferometer; 36. Bracewell's interferometric telescope; 37. Scanning optical microscopy; 38. Zernike's method of phase contrast; 39. Polarization microscopy; 40. Nomarski's differential interference contrast microscope; 41. The Van Leeuwenhoek microscope; 42. Projection photolithography; 43. Interaction of light with subwavelength structures; 44 The Ronchi test; 45. The Shack-Hartmann Wavefront sensor; 46. Ellipsometry; 47. Holography and holographic interferometry; 48. Self-focusing in non-linear optical media; 49
Classical databases and knowledge organization
Hjørland, Birger
2015-01-01
examines this claim and argues for the continued value of Boolean systems, which suggests two further considerations: (1) the important role of human expertise in searching (expert searchers and “information literate” users) and (2) the role of library and information science and knowledge organization (KO......) in the design and use of classical databases. An underlying issue is the kind of retrieval system for which one should aim. Warner’s (2010) differentiation between the computer science traditions and an older library-oriented tradition seems important; the former aim to transform queries automatically...
Solar Activity and Classical Physics
无
2001-01-01
This review of solar physics emphasizes several of the more conspicuous scientific puzzles posed by contemporary observational knowledge of the magnetic activity of the Sun. The puzzles emphasize how much classical physics we have yet to learn from the Sun. The physics of solar activity is based on the principles of Newton, Maxwell, Lorentz, Boltzmann, et. al., along with the principles of radiative transfer. In the large, these principles are expressed by magnetohydrodynamics. A brief derivation of the magnetohydrodynamic induction and momentum equations is provided, with a discussion of popular misconceptions.
Lectures on classical differential geometry
Struik, Dirk J
1988-01-01
Elementary, yet authoritative and scholarly, this book offers an excellent brief introduction to the classical theory of differential geometry. It is aimed at advanced undergraduate and graduate students who will find it not only highly readable but replete with illustrations carefully selected to help stimulate the student's visual understanding of geometry. The text features an abundance of problems, most of which are simple enough for class use, and often convey an interesting geometrical fact. A selection of more difficult problems has been included to challenge the ambitious student.Writ
Motions of Classical Charged Tachyons
Davidson, M P
2001-01-01
It is shown by numerical simulation that classical charged tachyons have self-orbiting helical solutions in a narrow neighborhood of certain discrete values for the velocity when the electromagnetic interaction is described by Feynman-Wheeler electrodynamics. The force rapidly oscillates between attractive and repulsive as a function of velocity in this neighborhood. Causal electrodynamics is also considered, and in this case it is found that when the force is attractive the tachyon loses energy to radiation. Only certain narrow ranges of velocity give attractive forces, and a geometrical derivation of these special velocities is given. Possible implications of these results for hidden variable theories of quantum mechanics are conjectured.
Classical trajectories and quantum tunneling
Ivlev, B I
2003-01-01
The problem of inter-band tunneling in a semiconductor (Zener breakdown) in a nonstationary and homogeneous electric field is solved exactly. Using the exact analytical solution, the approximation based on classical trajectories is studied. A new mechanism of enhanced tunneling through static non-one-dimensional barriers is proposed in addition to well known normal tunneling solely described by a trajectory in imaginary time. Under certain conditions on the barrier shape and the particle energy, the probability of enhanced tunneling is not exponentially small even for non-transparent barriers, in contrast to the case of normal tunneling.
Javanese Phrase Construction in Classical Books Translation
Moh. Masrukhi
2016-07-01
Full Text Available When the system or structure of language is used and influenced by other languages, it is called interference, and it may ruin the concept of structures. This research is about Arabic phrase construction that influenced Javanese phrase construction in classical books translation (TKK. This involvement appears when the concept of Arabic’s construction is translated literally into Javanese. The research was carried out by applying theories of interference and translation. It’s analysis approach with contrastive analysis which is allegedly enabled errors to be predicted from a comparison between Arabic’s and Javanese’s phrase construction. The data were found and collected from several classical books in Arabic language (KKbA translated by different writers. The results show that Javanese phrase construction (as the target language, particularly, with noun phrases, with adjectival phrases, with numeral phrases, and with prepositional phrases was influenced by Arabic’s murakkab or Arabic phrase construction (as the source language. Arabic has its own concept of phrase construction. The phrase construction cannot be translated into Javanese directly through word-for-word translation or literal translation. Thus, Javanese in TKK became inconvenient and ungrammatical. Arabic phrase construction is flipped around (with noun phrases and adjectival phrases and prepositions are used and translated improperly or in the wrong position (with prepositional phrases. This research has many implications for further use, such as: for the identification and description of the deviation of Javanese phrase construction which has been affected by direct translation from the Arabic language, and furthermore, to increase the knowledge of those who are learning by increasing the realization and awareness in writing and translating (especially from Arabic to Javanese about the fact that Arabic and Javanese have their own regulations or
ENVIRONMENTALISM AND CLASSIC PARADIGMS OF INTERNATIONAL RELATIONS
D. D. Miniaeva
2014-06-01
Full Text Available This article examines an environmentalism integration process into Three classical paradigms of international relations theory (Liberalism, Realism and Marxism into Three classical paradigms of international relations theory (Liberalism, Realism and Marxism. The main purpose of this study is to reveal the result of this integration. Methods used in this article include analysis and comparison of "ecological" paradigms on selected parameters (the nature of international relations, actors, targets, tools, processes. Results of research show that the beginning of the XXI century is distinguished by the development of new types of political concepts that explain interaction of elements in modern international relations in the area of environmental protection. The reason of these changes lies in the phenomena of environmentalism integration into Three paradigms of international relations. However, we cannot say that any of the examined paradigms accumulated all features of environmentalism without their modification. Better to say, it's rather similar to adaptation of environmental ideas. Therefore, to understand modern international relations processes, it is necessary to take into account their environmental element. Purchase on Elibrary.ru > Buy nowDOI: http://dx.doi.org/10.12731/2070-7568-2014-3-4
The revision of classical stock model
YE Bai-qing; WANG Hong-li
2001-01-01
On the basis of the analysis of classical stock model, according to th e limitation of the model, the article puts forward the revision of classical mo del and enforces the applicability of the stock model.
The revision of classical stock model
叶柏青; 王洪利
2001-01-01
On the basis of the analysis of classical stock model, according to the limitation of the model, the article puts forward the revision of classical model and enforces the applicability of the stock model.
Could a Mobile-Assisted Learning System Support Flipped Classrooms for Classical Chinese Learning?
Wang, Y.-H.
2016-01-01
In this study, the researcher aimed to develop a mobile-assisted learning system and to investigate whether it could promote teenage learners' classical Chinese learning through the flipped classroom approach. The researcher first proposed the structure of the Cross-device Mobile-Assisted Classical Chinese (CMACC) system according to the pilot…
Representational Realism, Closed Theories and the Quantum to Classical Limit
de Ronde, Christian
2016-01-01
In this paper we discuss the representational realist stance as a pluralist ontic approach to inter-theoretic relationships. Our stance stresses the fact that physical theories require the necessary consideration of a conceptual level of discourse which determines and configures the specific field of phenomena discussed by each particular theory. We will criticize the orthodox line of research which has grounded the analysis about QM in two (Bohrian) metaphysical presuppositions -accepted in the present as dogmas that all interpretations must follow. We will also examine how the orthodox project of "bridging the gap" between the quantum and the classical domains has constrained the possibilities of research, producing only a limited set of interpretational problems which only focus in the justification of "classical reality" and exclude the possibility of analyzing the possibilities of non-classical conceptual representations of QM. The representational realist stance introduces two new problems, namely, the ...
About the modern house - and the classical
Hauberg, Jørgen
2010-01-01
In text and illustrations describes the classical house and the classical city, represented by Andrea Palladio (1508-80), and the modern house, the modern city and building task, represented by Le Corbusier (1857-1965).......In text and illustrations describes the classical house and the classical city, represented by Andrea Palladio (1508-80), and the modern house, the modern city and building task, represented by Le Corbusier (1857-1965)....
Seven Steps Towards the Classical World
Allori, Valia; Dürr, Detlef; Goldstein, Shelly; Zanghí, Nino
2001-01-01
Classical physics is about real objects, like apples falling from trees, whose motion is governed by Newtonian laws. In standard Quantum Mechanics only the wave function or the results of measurements exist, and to answer the question of how the classical world can be part of the quantum world is a rather formidable task. However, this is not the case for Bohmian mechanics, which, like classical mechanics, is a theory about real objects. In Bohmian terms, the problem of the classical limit be...
余凯亮
2012-01-01
This paper tries to discuss different characteristics of timing, space and efforts of using sword in martial arts, drama and dance in order to explore their different concepts on swords and to explore the spirit of traditional culture embedded in Chinese classical dance.%该论文从武术、戏曲、舞蹈几种不同的身体文化出发，借对比分析它们的时、空、力特征，以求论述“武剑”、“剑舞”的不同追求，探讨“中国古典舞剑舞”课程所蕴含的传统艺术精髓，为古典舞剑舞的未来提供发展依据和支撑。
Valeria Victoria IOVANOV
2014-05-01
Full Text Available A CNC machine makes use of mathematics and various coordinate systems to understand and process the information it receives to determine what to move where and how fast . The most important function of any CNC machine is precise and rigorous control of the movement. All CNC equipment have two or more directions of motion, called axes. CNC machines are driven by computer controlled servo motors and generally guided by a stored program, the type of movement (fast , linear, circular , the moving axes, the distances of movement and the speed of movement ( processing being programmable for most CNC machines . This paper proposes the design and implementation of a G code programming language for the reference point Case R290 - 02IS the short version compared to the classical part of the garland product C3G 1200,1400,1600 , reference points used in all fields that use conveyors .
范郑丽; 隋建峰; 李蕊; 万子兵; 赵红梅
2009-01-01
目的 以眼肌电记录法分别记录豚鼠以声音和光信号作为条件刺激(CS)的眨眼条件反射(CR),分析并比较其习得规律.方法 采用金属电极埋植技术及简易"随动"气流给气刺激装置,分别以声音和光信号作为条件刺激(CS),以气流作为非条件刺激(US),以眼肌电信号判断其眨眼行为,在清醒无制动的豚鼠上进行经典眨眼条件反射的训练.结果 在豚鼠内眦采集并记录到眨眼肌电信号显示,声音条件刺激组在第1天、第4天、第7天、第10天的CR习得率分别为(5.0±1.09)%、(31.0±2.09)%、(61.33±1.63)%、(82.33±1.63)%,而光条件刺激组在第1天、第4天、第7天、第10天的CR习得率分别为(5.5±4.59)%、(4.33±3.14)%、(10.83±13.42)%、(3.83±1.33)%,2组CR习得率差异有显著性(P<0.05).结论 以声音作为条件刺激时豚鼠能够成功建立的眨眼条件反射,而以光作为条件刺激时眨眼条件反射的建立却非常困难.%Objective To record the classical eyeblink conditioning single,which the conditioned stimu-lus(CS) is tone or light, by the electromyographic (EMG) of musculi oculi recording. Methods Adopting metal electrode embedding technic and simple air puff stimulus facility ,tone or light as the conditioned stimulus(CS) was paired with air puff being unconditioned stimulus(US) to establish classical eyeblink conditioning of conscious un-fixed guinea pigs. The eyeblink behavior were evaluated through EMG of musculi oculi. Results The eyeblink EMG signal of musculi oculi showed: when the tone as the CS , the results indicated that the acquisition rate of the 1st,the 4th,the 7th,the 10th day were respectively (5.0±1.09)%,(31.0±2.09)%,(61.33±1.63)%,(82.33±1.63) % ; when the light as the CS , the results indicate that the acquisition rate of the 1 st, the 4th, the 7th, the 10th day were respectively (5.5±4.59) %, (4.33±3.14) %, (10.83±13.42)%, (3.83±1.33 ) %. Conclu-sion While CS is tone,classical eyeblink
岑泽丽
2014-01-01
China's four great classics is an important part of Chinese excellent traditional culture,excavation and study of the educational value of their modern humanistic qualities that can help contemporary college students to improve the moral character,improve personality training,foster the ideal personality,en-hance political literacy.%中国四大名著是中华优秀传统文化的重要组成部分，挖掘并研究它们的现代人文素质的教育价值，能够帮助当代大学生完善道德品质，提高人格修养，培育理想人格，提升政治素养。
Curiel, Erik
2014-01-01
In the early 1970s it is was realized that there is a striking formal analogy between the Laws of black-hole mechanics and the Laws of classical thermodynamics. Before the discovery of Hawking radiation, however, it was generally thought that the analogy was only formal, and did not reflect a deep connection between gravitational and thermodynamical phenomena. It is still commonly held that the surface gravity of a stationary black hole can be construed as a true physical temperature and its area as a true entropy only when quantum effects are taken into account; in the context of classical general relativity alone, one cannot cogently construe them so. Does the use of quantum field theory in curved spacetime offer the only hope for taking the analogy seriously? I think the answer is `no'. To attempt to justify that answer, I shall begin by arguing that the standard argument to the contrary is not physically well founded, and in any event begs the question. Looking at the various ways that the ideas of "tempe...
Overuse injuries in classical ballet.
Khan, K; Brown, J; Way, S; Vass, N; Crichton, K; Alexander, R; Baxter, A; Butler, M; Wark, J
1995-05-01
Successful management of classical ballet dancers with overuse injuries requires an understanding of the art form, precise knowledge of anatomy and awareness of certain conditions. Turnout is the single most fundamental physical attribute in classical ballet and 'forcing turnout' frequently contributes to overuse injuries. Common presenting conditions arising from the foot and ankle include problems at the first metatarsophalangeal joint, second metatarsal stress fractures, flexor hallucis longus tendinitis and anterior and posterior ankle impingement syndromes. Persistent shin pain in dancers is often due to chronic compartment syndrome, stress fracture of the posteromedial or anterior tibia. Knee pain can arise from patellofemoral syndrome, patellar tendon insertional pathologies, or a combination of both. Hip and back problems are also prevalent in dancers. To speed injury recovery of dancers, it is important for the sports medicine team to cooperate fully. This permits the dancer to benefit from accurate diagnosis, technique correction where necessary, the full range of manual therapies to joint and soft tissue, appropriate strengthening programmes and maintenance of dance fitness during any time out of class with Pilates-based exercises and nutrition advice. Most overuse ballet conditions respond well to a combination of conservative therapies. Those dancers that do require surgical management still depend heavily on ballet-specific rehabilitation for a complete recovery.
Classical equations for quantum systems
Gell-Mann, M. (Theoretical Astrophysics Group (T-6), Los Alamos National Laboratory, Los Alamos, New Mexico 87545) (United States) (Santa Fe Institute, 1660 Old Pecos Trail, Santa Fe, New Mexico 87501); Hartle, J.B. (Department of Physics, University of California enSanta Barbara, Santa Barbara, (California) 93106)
1993-04-15
The origin of the phenomenological deterministic laws that approximately govern the quasiclassical domain of familiar experience is considered in the context of the quantum mechanics of closed systems such as the universe as a whole. A formulation of quantum mechanics is used that predicts probabilities for the individual members of a set of alternative coarse-grained histories that [ital decohere], which means that there is negligible quantum interference between the individual histories in the set. We investigate the requirements for coarse grainings to yield decoherent sets of histories that are quasiclassical, i.e., such that the individual histories obey, with high probability, effective classical equations of motion interrupted continually by small fluctuations and occasionally by large ones. We discuss these requirements generally but study them specifically for coarse grainings of the type that follows a distinguished subset of a complete set of variables while ignoring the rest. More coarse graining is needed to achieve decoherence than would be suggested by naive arguments based on the uncertainty principle. Even coarser graining is required in the distinguished variables for them to have the necessary inertia to approach classical predictability in the presence of the noise consisting of the fluctuations that typical mechanisms of decoherence produce. We describe the derivation of phenomenological equations of motion explicitly for a particular class of models.
Physiological characteristics of classical ballet.
Schantz, P G; Astrand, P O
1984-10-01
The aerobic and anaerobic energy yield during professional training sessions ("classes") of classical ballet as well as during rehearsed and performed ballets has been studied by means of oxygen uptake, heart rate, and blood lactate concentration determinations on professional ballet dancers from the Royal Swedish Ballet in Stockholm. The measured oxygen uptake during six different normal classes at the theatre averaged about 35-45% of the maximal oxygen uptake, and the blood lactate concentration averaged 3 mM (N = 6). During 10 different solo parts of choreographed dance (median length = 1.8 min) representative for moderately to very strenuous dance, an average oxygen uptake (measured during the last minute) of 80% of maximum and blood lactate concentration of 10 mM was measured (N = 10). In addition, heart rate registrations from soloists in different ballets during performance and final rehearsals frequently indicated a high oxygen uptake relative to maximum and an average blood lactate concentration of 11 mM (N = 5). Maximal oxygen uptake, determined in 1971 (N = 11) and 1983 (N = 13) in two different groups of dancers, amounted to on the average 51 and 56 ml X min-1 X kg-1 for the females and males, respectively. In conclusion, classical ballet is a predominantly intermittent type of exercise. In choreographed dance each exercise period usually lasts only a few minutes, but can be very demanding energetically, while during the dancers' basic training sessions, the energy yield is low.
Fluctuations in classical sum rules.
Elton, John R; Lakshminarayan, Arul; Tomsovic, Steven
2010-10-01
Classical sum rules arise in a wide variety of physical contexts. Asymptotic expressions have been derived for many of these sum rules in the limit of long orbital period (or large action). Although sum-rule convergence may well be exponentially rapid for chaotic systems in a global phase-space sense with time, individual contributions to the sums may fluctuate with a width which diverges in time. Our interest is in the global convergence of sum rules as well as their local fluctuations. It turns out that a simple version of a lazy baker map gives an ideal system in which classical sum rules, their corrections, and their fluctuations can be worked out analytically. This is worked out in detail for the Hannay-Ozorio sum rule. In this particular case the rate of convergence of the sum rule is found to be governed by the Pollicott-Ruelle resonances, and both local and global boundaries for which the sum rule may converge are given. In addition, the width of the fluctuations is considered and worked out analytically, and it is shown to have an interesting dependence on the location of the region over which the sum rule is applied. It is also found that as the region of application is decreased in size the fluctuations grow. This suggests a way of controlling the length scale of the fluctuations by considering a time dependent phase-space volume, which for the lazy baker map decreases exponentially rapidly with time.
Research on Network Digital Game with the Classic Cultural Transmission Mechanism%网络数字游戏与经典文化传播机制研究
徐谨力
2014-01-01
Impact of network digital games on people becomes increasingly apparent, as a product of popular culture, both the property itself and dissemination of cultural heritage. This article from the network digital game in the dissemination of culture should adhere to the authenticity of the epidemic, entertainment and other principles, the classical cultural heritage in order to better play the role of educational enlightenment games, online digital games should select the game from the cultural background visual design elements, language composition, the game is set trigger settings and virtual identities five aspects, in order to complete the subtle spread of classical culture.%网络数字游戏对人们的影响日益显现，其作为大众文化的产物，本身也兼具文化传承与传播的属性。本文从网络数字游戏在传播文化中应坚持的真实性、流行性、娱乐性等原则出发，为了使其更好传承经典文化，发挥游戏的教育教化作用，网络数字游戏应当从游戏背景文化的选择、视觉要素的设计、语言文字的构成、游戏触发因素的设置与虚拟身份的设定等五个方面入手，借以完成经典文化潜移默化的传播。
Collection of problems in classical mechanics
Kotkin, G L; ter Haar, D
1971-01-01
Collection of Problems in Classical Mechanics presents a set of problems and solutions in physics, particularly those involving mechanics. The coverage of the book includes 13 topics relevant to classical mechanics, such as integration of one-dimensional equations of motion; the Hamiltonian equations of motion; and adiabatic invariants. The book will be of great use to physics students studying classical mechanics.
Self compensation of classical non abelian charge
Bartnik, E. A.
2009-01-01
A new classical, non singular solution with arbitrarily low energy is found for SU(2) non abelian fields in the presence of a static charge. Physically it means that a classical charge coupled to any SU(N) non abelian gauge field will develop a pure gauge field, carrying no energy, that will completely screen it - there are no visible classical non abelian charges.
Quantum-classical hybrid dynamics - a summary
Elze, Hans-Thomas
2013-01-01
A summary of a recently proposed description of quantum-classical hybrids is presented, which concerns quantum and classical degrees of freedom of a composite object that interact directly with each other. This is based on notions of classical Hamiltonian mechanics suitably extended to quantum mechanics.
Quantum revivals in two degrees of freedom integrable systems : the torus case
Lablée, Olivier
2010-01-01
The paper deals with the semi-classical behaviour of quantum dynamics for a semi-classical completely integrable system with two degrees of freedom near Liouville regular torus. The phenomomenon of wave packet revivals is demonstrated in this article. The framework of this paper is semi-classical analysis (limit :). For the proofs we use standard tools of real analysis, Fourier analysis and basic analytic number theory.
Making the Transition from Classical to Quantum Physics
Dutt, Amit
2011-01-01
This paper reports on the nature of the conceptual understandings developed by Year 12 Victorian Certificate of Education (VCE) physics students as they made the transition from the essentially deterministic notions of classical physics, to interpretations characteristic of quantum theory. The research findings revealed the fact that the…
Psychosocial developmental milestones in men with classic galactosemia
Gubbels, C.S.; Maurice-Stam, H.; Berry, G.T.; Bosch, A.M.; Waisbren, S.; Rubio-Gozalbo, M.E.; Grootenhuis, M.A.
2011-01-01
Patients with classic galactosemia suffer from several long term effects of their disease. Research in a group of mainly female patients has shown that these patients may also have a developmental delay with regard to their social aptitude. To study if male galactosemia patients achieve psychosocial
Making the Transition from Classical to Quantum Physics
Dutt, Amit
2011-01-01
This paper reports on the nature of the conceptual understandings developed by Year 12 Victorian Certificate of Education (VCE) physics students as they made the transition from the essentially deterministic notions of classical physics, to interpretations characteristic of quantum theory. The research findings revealed the fact that the…
Scientific Realism and Classical Physics
Singh, Virendra
2008-01-01
We recount the successful long career of classical physics, from Newton to Einstein, which was based on the philosophy of scientific realism. Special emphasis is given to the changing status and number of ontological entitities and arguments for their necessity at any time. Newton, initially, began with (i) point particles, (ii) aether, (iii) absolute space and (iv) absolute time. The electromagnetic theory of Maxwell and Faraday introduced `fields' as a new ontological entity not reducible to earlier ones. Their work also unified electricity, magnetism and optics. Repeated failure to observe the motion of earth through aether led Einstein to modify the Newtonian absolute space and time concepts to a fused Minkowski space-time and the removal of aether from basic ontological entities in his special theory of relativity. Later Einstein in his attempts to give a local theory of gravitation was led to further modify flat Minkowski space-time to the curved Riemannian space time. This reduced gravitational phenome...
Hydrogen Beyond the Classic Approximation
Scivetti, I
2003-01-01
The classical nucleus approximation is the most frequently used approach for the resolution of problems in condensed matter physics.However, there are systems in nature where it is necessary to introduce the nuclear degrees of freedom to obtain a correct description of the properties.Examples of this, are the systems with containing hydrogen.In this work, we have studied the resolution of the quantum nuclear problem for the particular case of the water molecule.The Hartree approximation has been used, i.e. we have considered that the nuclei are distinguishable particles.In addition, we have proposed a model to solve the tunneling process, which involves the resolution of the nuclear problem for configurations of the system away from its equilibrium position
Classically Stable Nonsingular Cosmological Bounces
Ijjas, Anna; Steinhardt, Paul J.
2016-09-01
One of the fundamental questions of theoretical cosmology is whether the Universe can undergo a nonsingular bounce, i.e., smoothly transit from a period of contraction to a period of expansion through violation of the null energy condition (NEC) at energies well below the Planck scale and at finite values of the scale factor such that the entire evolution remains classical. A common claim has been that a nonsingular bounce either leads to ghost or gradient instabilities or a cosmological singularity. In this Letter, we consider a well-motivated class of theories based on the cubic Galileon action and present a procedure for explicitly constructing examples of a nonsingular cosmological bounce without encountering any pathologies and maintaining a subluminal sound speed for comoving curvature modes throughout the NEC violating phase. We also discuss the relation between our procedure and earlier work.
Agglomeration Economies in Classical Music
Borowiecki, Karol Jan
2015-01-01
This study investigates agglomeration effects for classical music production in a wide range of cities for a global sample of composers born between 1750 and 1899. Theory suggests a trade-off between agglomeration economies (peer effects) and diseconomies (peer crowding). I test this hypothesis...... using historical data on composers and employ a unique instrumental variable – a measure of birth centrality, calculated as the average distance between a composer’s birthplace and the birthplace of his peers. I find a strong causal impact of peer group size on the number of important compositions......’ productivity, and across different estimations in which also time-varying birth centrality measures are used as instrumental variables....
From classical to quantum fields
Baulieu, Laurent; Sénéor, Roland
2017-01-01
Quantum Field Theory has become the universal language of most modern theoretical physics. This introductory textbook shows how this beautiful theory offers the correct mathematical framework to describe and understand the fundamental interactions of elementary particles. The book begins with a brief reminder of basic classical field theories, electrodynamics and general relativity, as well as their symmetry properties, and proceeds with the principles of quantisation following Feynman's path integral approach. Special care is used at every step to illustrate the correct mathematical formulation of the underlying assumptions. Gauge theories and the problems encountered in their quantisation are discussed in detail. The last chapters contain a full description of the Standard Model of particle physics and the attempts to go beyond it, such as grand unified theories and supersymmetry. Written for advanced undergraduate and beginning graduate students in physics and mathematics, the book could also serve as a re...
Theoretical physics 1 classical mechanics
Nolting, Wolfgang
2016-01-01
This textbook offers a clear and comprehensive introduction to classical mechanics, one of the core components of undergraduate physics courses. The book starts with a thorough introduction to the mathematical tools needed, to make this textbook self-contained for learning. The second part of the book introduces the mechanics of the free mass point and details conservation principles. The third part expands the previous to mechanics of many particle systems. Finally the mechanics of the rigid body is illustrated with rotational forces, inertia and gyroscope movement. Ideally suited to undergraduate students in their first year, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this series...
GALK inhibitors for classic galactosemia.
Lai, Kent; Boxer, Matthew B; Marabotti, Anna
2014-06-01
Classic galactosemia is an inherited metabolic disease for which, at present, no therapy is available apart from galactose-restricted diet. However, the efficacy of the diet is questionable, since it is not able to prevent the insurgence of chronic complications later in life. In addition, it is possible that dietary restriction itself could induce negative side effects. Therefore, there is a need for an alternative therapeutic approach that can avert the manifestation of chronic complications in the patients. In this review, the authors describe the development of a novel class of pharmaceutical agents that target the production of a toxic metabolite, galactose-1-phosphate, considered as the main culprit for the cause of the complications, in the patients.
Classic ballet dancers postural patterns
Joseani Paulini Neves Simas
2008-06-01
Full Text Available The aim of this study was to evaluate classic ballet practice and its influence on postural patterns and (a identify the most frequent postural changes; (b determine the postural pattern; (c verify the existence of association of practice time and postural changes. The investigation was carried out in two stages: one, description in which 106 dancers participated; the other, causal comparative in which 50 dancers participated; and (a questionnaire; (b a checkerboard; (c postural chart; (d measure tape; (e camera and (f pedoscope were used as instrument. Descriptive and inferential statistics was used for analysis. The results revealed the most frequent postural changes such as hyperlordosis, unleveled shoulders and pronated ankles. Ballet seems to have negative implications in the postural development , affecting especially the vertebral spine, trunk and feet. The practice time was not a parameter to indicate the increase in postural changes. In conclusion, ballet may be associated with postural changes and determining a characteristic postural pattern.
Classical scattering from oscillating targets
Papachristou, P.K.; Diakonos, F.K.; Constantoudis, V.; Schmelcher, P.; Benet, L
2002-12-30
We study planar classical scattering from an oscillating heavy target whose dynamics defines a five-dimensional phase space. Although the system possesses no periodic orbits, and thus topological chaos is not present, the scattering functions display a variety of structures on different time scales. These structures are due to scattering events with a strong energy transfer from the projectile to the moving disk resulting in low-velocity peaks. We encounter initial conditions for which the projectile exhibits infinitely many bounces with the oscillating disk. Our numerical investigations are supported by analytical results on a specific model with a simple time-law. The observed properties possess universal character for scattering off oscillating targets.
Introducing Newton and classical physics
Rankin, William
2002-01-01
The rainbow, the moon, a spinning top, a comet, the ebb and flood of the oceans ...a falling apple. There is only one universe and it fell to Isaac Newton to discover its secrets. Newton was arguably the greatest scientific genius of all time, and yet he remains a mysterious figure. Written and illustrated by William Rankin, "Introducting Newton and Classical Physics" explains the extraordinary ideas of a man who sifted through the accumulated knowledge of centuries, tossed out mistaken beliefs, and single-handedly made enormous advances in mathematics, mechanics and optics. By the age of 25, entirely self-taught, he had sketched out a system of the world. Einstein's theories are unthinkable without Newton's founding system. He was also a secret heretic, a mystic and an alchemist, the man of whom Edmund Halley said "Nearer to the gods may no man approach!". This is an ideal companion volume to "Introducing Einstein".
Classical Syllogisms in Logic Teaching
Øhrstrøm, Peter; Sandborg-Petersen, Ulrik; Thorvaldsen, Steinar
2013-01-01
have a tendency correctly to assess valid syllogisms as such more often than correctly assessing invalid syllogisms as such. It is also investigated to what extent the students have improved their skills in practical reasoning by attending the logic courses. Finally, some open questions regarding......This paper focuses on the challenges of introducing classical syllogisms in university courses in elementary logic and human reasoning. Using a program written in Prolog+CG, some empirical studies have been carried out involving three groups of students in Denmark; one group of philosophy students...... and two groups of students of informatics. The skills of the students in syllogistic reasoning before and after the logic courses have been studied and are discussed. The empirical observations made with the program make it possible to identify syllogisms which are found difficult by the students...
Inflation and classical scale invariance
Racioppi, Antonio
2014-01-01
BICEP2 measurement of primordial tensor modes in CMB suggests that cosmological inflation is due to a slowly rolling inflaton taking trans-Planckian values and provides further experimental evidence for the absence of large $M_{\\rm P}$ induced operators. We show that classical scale invariance solves the problem and allows for a remarkably simple scale-free inflaton model without any gauge group. Due to trans-Planckian inflaton values and VEVs, a dynamically induced Coleman-Weinberg-type inflaton potential of the model can predict tensor-to-scalar ratio $r$ in a large range. Precise determination of $r$ in future experiments will allow to test the proposed field-theoretic framework.
A Classical Model of Gravitation
Wagener P.
2008-07-01
Full Text Available A classical model of gravitation is proposed with time as an independent coordinate. The dynamics of the model is determined by a proposed Lagrangian. Applying the canonical equations of motion to its associated Hamiltonian gives conservation equa- tions of energy, total angular momentum and the z component of the angular momen- tum. These lead to a Keplerian orbit in three dimensions, which gives the observed values of perihelion precession and bending of light by a massive object. An expression for gravitational redshift is derived by accepting the local validity of special relativity at all points in space. Exact expressions for the GEM relations, as well as their associated Lorentz-type force, are derived. An expression for Mach’s Principle is also derived.
Classical electromagnetism in a nutshell
Garg, Anupam
2012-01-01
This graduate-level physics textbook provides a comprehensive treatment of the basic principles and phenomena of classical electromagnetism. While many electromagnetism texts use the subject to teach mathematical methods of physics, here the emphasis is on the physical ideas themselves. Anupam Garg distinguishes between electromagnetism in vacuum and that in material media, stressing that the core physical questions are different for each. In vacuum, the focus is on the fundamental content of electromagnetic laws, symmetries, conservation laws, and the implications for phenomena such as radiation and light. In material media, the focus is on understanding the response of the media to imposed fields, the attendant constitutive relations, and the phenomena encountered in different types of media such as dielectrics, ferromagnets, and conductors. The text includes applications to many topical subjects, such as magnetic levitation, plasmas, laser beams, and synchrotrons.
Classical mechanics of nonconservative systems.
Galley, Chad R
2013-04-26
Hamilton's principle of stationary action lies at the foundation of theoretical physics and is applied in many other disciplines from pure mathematics to economics. Despite its utility, Hamilton's principle has a subtle pitfall that often goes unnoticed in physics: it is formulated as a boundary value problem in time but is used to derive equations of motion that are solved with initial data. This subtlety can have undesirable effects. I present a formulation of Hamilton's principle that is compatible with initial value problems. Remarkably, this leads to a natural formulation for the Lagrangian and Hamiltonian dynamics of generic nonconservative systems, thereby filling a long-standing gap in classical mechanics. Thus, dissipative effects, for example, can be studied with new tools that may have applications in a variety of disciplines. The new formalism is demonstrated by two examples of nonconservative systems: an object moving in a fluid with viscous drag forces and a harmonic oscillator coupled to a dissipative environment.
Polarimetry by classical ghost diffraction
Kellock, Henri; Friberg, Ari T; Shirai, Tomohiro
2014-01-01
We present a technique for studying the polarimetric properties of a birefringent object by means of classical ghost diffraction. The standard ghost diffraction setup is modified to include polarizers for controlling the state of polarization of the beam in various places. The object is characterized by a Jones matrix and the absolute values of the Fourier transforms of its individual elements are measured. From these measurements the original complex-valued functions can be retrieved through iterative methods resulting in the full Jones matrix of the object. We present two different placements of the polarizers and show that one of them leads to better polarimetric quality, while the other placement offers the possibility to perform polarimetry without controlling the source's state of polarization. The concept of an effective source is introduced to simplify the calculations. Ghost polarimetry enables the assessment of polarization properties as a function of position within the object through simple intens...
Bettini, Alessandro
This first volume covers the mechanics of point particles, gravitation, extended systems (starting from the two-body system), the basic concepts of relativistic mechanics and the mechanics of rigid bodies and fluids. The four-volume textbook, which covers electromagnetism, mechanics, fluids and thermodynamics, and waves and light, is designed to reflect the typical syllabus during the first two years of a calculus-based university physics program. Throughout all four volumes, particular attention is paid to in-depth clarification of conceptual aspects, and to this end the historical roots of the principal concepts are traced. Writings by the founders of classical mechanics, G. Galilei and I. Newton, are reproduced, encouraging students to consult them. Emphasis is also consistently placed on the experimental basis of the concepts, highlighting the experimental nature of physics. Whenever feasible at the elementary level, concepts relevant to more advanced courses in modern physics are included. Each chapter b...
Gastrointestinal Health in Classic Galactosemia.
Shaw, Kelly A; Mulle, Jennifer G; Epstein, Michael P; Fridovich-Keil, Judith L
2016-07-01
Classic galactosemia (CG) is an autosomal recessive disorder of galactose metabolism that affects approximately 1/50,000 live births in the USA. Following exposure to milk, which contains large quantities of galactose, affected infants may become seriously ill. Early identification by newborn screening with immediate dietary galactose restriction minimizes or prevents the potentially lethal acute symptoms of CG. However, more than half of individuals with CG still experience long-term complications including cognitive disability, behavioral problems, and speech impairment. Anecdotal reports have also suggested frequent gastrointestinal (GI) problems, but this outcome has not been systematically addressed. In this study we explored the prevalence of GI symptoms among 183 children and adults with CG (cases) and 190 controls. Cases reported 4.5 times more frequent constipation (95% CI 1.8-11.5) and 4.2 times more frequent nausea (95% CI 1.2-15.5) than controls. Cases with genotypes predicting residual GALT activity reported less frequent constipation than cases without predicted GALT activity but this difference was not statistically significant. Because the rigor of dietary galactose restriction varies among individuals with galactosemia, we further tested whether GI symptoms associated with diet in infancy. Though constipation was almost four times as common among cases reporting a more restrictive diet in infancy, this difference was not statistically significant. These data confirm that certain GI symptoms are more common in classic galactosemia compared to controls and suggest that future studies should investigate associations with residual GALT activity and dietary galactose restriction in early life.
Citation classics in pediatric orthopaedics.
Varghese, Ranjit A; Dhawale, Arjun A; Zavaglia, Bogard C; Slobogean, Bronwyn L; Mulpuri, Kishore
2013-09-01
The purpose of this study was to identify the clinical pediatric orthopaedic articles with at least 100 citations published in all orthopaedic journals and to examine their characteristics. All journals dedicated to orthopaedics and its subspecialties were selected from the Journal Citation Report 2001 under the subject category "orthopedics." Articles cited 100 times or more were identified using the database of the Science Citation Index Expanded (SCI-EXPANDED, 1900 to present). The articles were ranked in a comprehensive list. Two authors independently reviewed the full text of each article and applied the inclusion and exclusion criteria to the list of articles. The 2 lists were then compared. All disagreements were resolved by consensus with input from the senior author. The final list of pediatric orthopaedic articles was then compiled. There were a total of 49 journals under the search category "orthopedics." Five journals were excluded as they were non-English journals. The remaining 44 journals were screened for articles with at least 100 citations. A total of 135 clinical pediatric orthopaedic articles cited at least 100 times were included. The most cited article was cited 692 times. The mean number of citations per article was 159 (95% confidence interval, 145-173). All the articles were published between 1949 and 2001, with 1980 and 1989 producing the most citation classics (34). The majority (90) originated from the United States, followed by the United Kingdom (12) and Canada (11). Scoliosis/kyphosis was the most common topic with 26 papers. The second most common subject was hip disorders (24). Therapeutic studies were the most common study type (71). Ninety-seven papers were assigned a 4 for level of evidence. The list of citation classics in pediatric orthopaedic articles is useful for several reasons. It identifies important contributions to the field of pediatric orthopaedics and their originators; it facilitates the understanding and discourse
刘恩瑞; 任欢; 赵宇; 苏君
2015-01-01
Glioblastoma(GBM)is one of the most common primary intracranial tumor that has high de-gree of malignancy ,invasive ability and a fatal prognosis .In recent years ,with the development of modern technol-ogy in biomedical sciences ,the understanding on GBM has developed gradually from pathological diagnosis to mo -lecular classifications ,which is based on the molecular characteristics of genetic signatures .Based on gene expres-sion and DNA methylation patterns , primary glioblastoma is divided into four subtypes , including the classical , neural,proneural and mesenchymal .These molecular classifications are closely relevant to the biological charac-teristics of glioblastoma .This review briefly introduces the molecular classifications of primary glioblastoma , but mainly focuses on the changes of the major genetic EGFR ,PTEN and PI3K,CDKN2A in the classical subtype of GBM,and discusses the treatment strategies for primary glioblastoma .%目的：胶质母细胞瘤（ Glioblastoma，GBM）是颅内最常见的原发恶性肿瘤，其恶性程度高、侵袭能力强、预后差。近年来随着生物学技术的发展，对GBM的理解也从病理学诊断逐步转向分子病理机制的研究。根据基因表达和DNA甲基化的模式将原发性GBM分为经典型、间质型、前神经元型和神经元型四种亚型。这些分子分型与胶质母细胞瘤的生物学特性密切相关。本文简要介绍了原发胶质母细胞瘤的分子分型，重点关注经典型GBM中EGFR、PTEN、PI3K和CDKN2A四种特征性基因的变异情况，并且对经典型胶质母细胞瘤的治疗策略进行了探讨。
Hilbert space theory of classical electrodynamics
RAJAGOPAL A K; GHOSE PARTHA
2016-06-01
Classical electrodynamics is reformulated in terms of wave functions in the classical phase space of electrodynamics, following the Koopman–von Neumann–Sudarshan prescription for classical mechanics on Hilbert spaces sans the superselection rule which prohibits interference effects in classical mechanics. This is accomplished by transforming from a set of commutingobservables in one Hilbert space to another set of commuting observables in a larger Hilbert space. This is necessary to clarify the theoretical basis of the much recent work on quantum-like features exhibited by classical optics. Furthermore, following Bondar et al, {\\it Phys. Rev.} A 88, 052108 (2013), it is pointed out that quantum processes that preserve the positivity or nonpositivity of theWigner function can be implemented by classical optics. This may be useful in interpreting quantum information processing in terms of classical optics.
Starfield, Sue; Ravelli, Louise J.
2006-01-01
To what extent have postmodernism and research modalities which fundamentally question the notion of the objective researcher impacted on the production of Ph.D. theses in the humanities and social sciences? This paper examines the visual and verbal representations of the writerly self through the title pages, tables of contents and introductory…
Starfield, Sue; Ravelli, Louise J.
2006-01-01
To what extent have postmodernism and research modalities which fundamentally question the notion of the objective researcher impacted on the production of Ph.D. theses in the humanities and social sciences? This paper examines the visual and verbal representations of the writerly self through the title pages, tables of contents and introductory…
On-line Classical Guitar Course: Blogs for Music Education
José Luis Navarro; Gilles Lavigne; G. Guadalupe Martínez Salgado
2009-01-01
This article introduces an on-line course constructed by means of a blog. The tool was the main goal of a research project titled “Develop, Implementation and evaluation of a Hybrid Course Face to face-On Line for Teaching the Beginning to Play the Classical Guitar”. This work was a three steep project in which it was implemented, applied and evaluated. The on-line course was intended to prepare the students to learn the basic principles to start in classical music with the guitar. The result...
Lectures on classical and quantum theory of fields
Arodz, Henryk
2017-01-01
This textbook addresses graduate students starting to specialize in theoretical physics. It provides didactic introductions to the main topics in the theory of fields, while taking into account the contemporary view of the subject. The student will find concise explanations of basic notions essential for applications of the theory of fields as well as for frontier research in theoretical physics. One third of the book is devoted to classical fields. Each chapter contains exercises of varying degree of difficulty with hints or solutions, plus summaries and worked examples as useful. It aims to deliver a unique combination of classical and quantum field theory in one compact course.
AN ECLECTIC APPROACH TO THE EDUCATION OF THE CLASSICAL GUITAR
Muhittin OZDEMIR
2014-08-01
Full Text Available The purpose of this study was to examine whether teaching activities aimed to improve musical knowledge and skills of students, who took classical guitar lessons in individual instrument education classes, had an effect on the success of students’ performances. The study group of the research consisted of first year, second year and third year guitar students who took classical guitar courses within individual instrument education classes at Karadeniz Technical University, in the Music Education branch of Fine Arts Education Department in the academic year of 2012-2013. The research was designed according to the model of experimental design with the control groups for pretests and posttests. After reviewing the equivalency of guitar students, experimental (N=7 and control (N=7 groups were selected with the help of the impartial assignment method. In research, while the experimental group was introduced with special guitar education lessons prepared according to the systematic education model, for two successive periods of five weeks each; the traditional teaching method was employed for the control group. Pretests and posttests were administered two both groups. Based on the results, it can be said that classical guitar performance successes of students in experimental group have increased to a greater degree than those in control group after the treatment. In conclusion, it was found that the special guitar education program, which aimed to increase musical and technical knowledge and skills in playing classical guitar, was significantly more effective and improving than the traditional teaching methods.
Introduction to Classical Density Functional Theory by Computational Experiment
Jeanmairet, Guillaume; Levesque, Maximilien; Borgis, Daniel
2014-01-01
We present here an introductory practical course to classical density functional theory (cDFT). Density functional theories, whether quantum or classical, rely largely on nonintuitive abstract concepts and applied mathematics. They are nevertheless a powerful tool and an active field of research in physics and chemistry that led to the 1998 Nobel prize in chemistry. We here illustrate the DFT in its most mathematically simple and yet physically relevant form: the classical density functional theory of an ideal fluid in an external field, as applied to the prediction of the structure of liquid neon at the molecular scale. This introductory course is built around the production of a cDFT code written by students using the Mathematica language. In this way, they are brought to deal with (i) the cDFT theory itself, (ii) some basic concepts around the statistical mechanics of simple fluids, (iii) the underlying mathematical and numerical problem of functional minimization, and (iv) a functional programming languag...
Classical Statistics and Statistical Learning in Imaging Neuroscience
Danilo Bzdok
2017-10-01
Full Text Available Brain-imaging research has predominantly generated insight by means of classical statistics, including regression-type analyses and null-hypothesis testing using t-test and ANOVA. Throughout recent years, statistical learning methods enjoy increasing popularity especially for applications in rich and complex data, including cross-validated out-of-sample prediction using pattern classification and sparsity-inducing regression. This concept paper discusses the implications of inferential justifications and algorithmic methodologies in common data analysis scenarios in neuroimaging. It is retraced how classical statistics and statistical learning originated from different historical contexts, build on different theoretical foundations, make different assumptions, and evaluate different outcome metrics to permit differently nuanced conclusions. The present considerations should help reduce current confusion between model-driven classical hypothesis testing and data-driven learning algorithms for investigating the brain with imaging techniques.
Lectures on Classical and Quantum Theory of Fields
Arodź, Henryk
2010-01-01
This textbook on classical and quantum theory of fields addresses graduate students starting to specialize in theoretical physics. It provides didactic introductions to the main topics in the theory of fields, while taking into account the contemporary view of the subject. The student will find concise explanations of basic notions essential for applications of the theory of fields as well as for frontier research in theoretical physics. One third of the book is devoted to classical fields. Each chapter contains exercises of varying degree of difficulty with hints or solutions, plus summaries and worked examples as useful. The textbook is based on lectures delivered to students of theoretical physics at Jagiellonian University. It aims to deliver a unique combination of classical and quantum field theory in one compact course.
Lectures on classical and quantum theory of fields
Arodz, Henryk; Hadasz, Leszek [Jagiellonian Univ., Krakow (Poland). Inst. Physics
2010-07-01
This textbook on classical and quantum theory of fields addresses graduate students starting to specialize in theoretical physics. It provides didactic introductions to the main topics in the theory of fields, while taking into account the contemporary view of the subject. The student will find concise explanations of basic notions essential for applications of the theory of fields as well as for frontier research in theoretical physics. One third of the book is devoted to classical fields. Each chapter contains exercises of varying degree of difficulty with hints or solutions, plus summaries and worked examples as useful. The textbook is based on lectures delivered to students of theoretical physics at Jagiellonian University. It aims to deliver a unique combination of classical and quantum field theory in one compact course. (orig.)
Religious ecstasy in classical Sufism
Göran Ogén
1982-01-01
Full Text Available The purpose of this essay is to shed some light on the phenomenon of religious ecstasy as met within Islamic mysticism and there particularly during its classical period. In this case, the expression "classical Sufism" refers to the period of Sufi history from about 850 A.D. until circa 1100 A.D. In the Sufi vocabulary there is even a rather differentiated terminology concerning these ecstatic experiences or states; whether different descriptions of one and the same experience are involved or whether the terms actually describe different experiences is a question that we must set aside for the present. There are, however, Sufis expressing the opinion that these different states of mind are based on one single experience in spite of the difference in terms. A generic term for these experiences or states is not to be found in the Sufi terminology however, so the problem of which of these phenomena must be present in order for ecstasy to be evidenced—or which of them would be sufficient— does not therefore arise for the Sufis. So instead of speaking of religious ecstasy in general, they either refer to the single specific terms in question or else use the plural of one of the words employed to designate one of the terms we include in "religious ecstasy". They thus speak of "ecstasies", mawagid from the singular form wagd—if one should at all attempt a translation of this plural. This plural is a genuine Sufi construction and does not otherwise seem to occur in the Arabic language, except as a later borrowing. Psalmody based on the Koranic vocabulary remains the main procedure for putting oneself in ecstasy. If we add 'and listening to psalmody', we then obtain a fairly satisfactory picture of the external conditions for the Sufis' ecstasy until the eleventh century, when various innovations begin to appear. As far as the darwiš-dance is concerned, it is not until the thirteenth century with Rumi that it becomes transformed from an expression
扈丽媛; 焦海涛; 丁怡; 崔建斌
2015-01-01
目的 对近8年来笔者所在医院收治的劳力性热射病(exertional heatstroke,EHS)和非劳力性热射病(classic heatstroke,CHS)患者临床资料进行比较分析、总结.方法 收集2006年-2013年入住解放军89医院的热射病患者23例,其中劳力性热射病患者13例,为EHS组;非劳力性热射病患者10例,为CHS组.另选取8例同时期的轻中度中暑患者为对照组. 记录分析纳入本研究患者的一般资料、实验室检查指标和临床治疗措施以及预后等,运用统计学方法比较分析三组患者的血常规、凝血四项检验指标的变化情况. 结果 CHS组患者较EHS组和对照组平均发病年龄偏高,基础疾病多,后遗症多;三组白细胞(white blood cell,WBC)计数均较正常值[(4~10) ×109/L]偏高,但组间比较无显著性差异(P>0.05);EHS 组患者入院时血小板(platelet,PLT)计数明显低于对照组(P0.05).结论 CHS多见于老年体弱患者,多伴有基础疾病,多遗留后遗症;实验室检查结果显示,EHS和CHS患者出现明显的凝血功能障碍,且以EHS患者更严重,这可能是EHS致多器官功能障碍的主要发病机制.%Objective Clinical data of heatstroke patients which collected in author's hospital over past 8 yrs were analyzed. Methods The 23 cases of heatstroke,which collected in 89 People's Liberation Army Hospital 2006-2013,were divided into three groups: exertional heatstroke group (EHS group,13 cases),non-exertional (classic) heatstroke group (CHS group,10 cases),and 8 mild to moderate stroke cases as a control group. The general situation,clinical manifestation and lab exam parameters including blood routine test,blood clotting,liver function,renal function,muscle acid kinase were recorded and statistically analyzed. Results Compared with either EHS or control group,the CHS patients were older,more with underlying diseases and worse prognosis. White blood cells (WBC) of these three groups were increased,while there was no difference
On the co-creation of classical and modern physics.
Staley, Richard
2005-12-01
While the concept of "classical physics" has long framed our understanding of the environment from which modern physics emerged, it has consistently been read back into a period in which the physicists concerned initially considered their work in quite other terms. This essay explores the shifting currency of the rich cultural image of the classical/ modern divide by tracing empirically different uses of "classical" within the physics community from the 1890s to 1911. A study of fin-de-siècle addresses shows that the earliest general uses of the concept proved controversial. Our present understanding of the term was in large part shaped by its incorporation (in different ways) within the emerging theories of relativity and quantum theory--where the content of "classical" physics was defined by proponents of the new. Studying the diverse ways in which Boltzmann, Larmor, Poincaré, Einstein, Minkowski, and Planck invoked the term "classical" will help clarify the critical relations between physicists' research programs and their use of worldview arguments in fashioning modern physics.
Classical mutagenesis in higher plants
Koornneef, M.
2002-01-01
For a long time, mutagenesis research in plants focused on crop improvement and, especially for crop plants, opimised protocols were developed with barley being one of the favourite species. However, the interest in mutagenesis has shifted to basic plant research in the last 20 years, when the power
Classical mutagenesis in higher plants
Koornneef, M.
2002-01-01
For a long time, mutagenesis research in plants focused on crop improvement and, especially for crop plants, opimised protocols were developed with barley being one of the favourite species. However, the interest in mutagenesis has shifted to basic plant research in the last 20 years, when the power
Pembrolizumab in classical Hodgkin's lymphoma.
Maly, Joseph; Alinari, Lapo
2016-09-01
Pembrolizumab is a humanized monoclonal antibody directed against programmed cell death protein 1 (PD-1), a key immune-inhibitory molecule expressed on T cells and implicated in CD4+ T-cell exhaustion and tumor immune-escape mechanisms. Classical Hodgkin's lymphoma (cHL) is a unique B-cell malignancy in the sense that malignant Reed-Sternberg (RS) cells represent a small percentage of cells within an extensive immune cell infiltrate. PD-1 ligands are upregulated on RS cells as a consequence of both chromosome 9p24.1 amplification and Epstein-Barr virus infection and by interacting with PD-1 promote an immune-suppressive effect. By augmenting antitumor immune response, pembrolizumab and nivolumab, another monoclonal antibody against PD-1, have shown significant activity in patients with relapsed/refractory cHL as well as an acceptable toxicity profile with immune-related adverse events that are generally manageable. In this review, we explore the rationale for targeting PD-1 in cHL, review the clinical trial results supporting the use of checkpoint inhibitors in this disease, and present future directions for investigation in which this approach may be used.
Relaxation properties in classical diamagnetism
Carati, A.; Benfenati, F.; Galgani, L.
2011-06-01
It is an old result of Bohr that, according to classical statistical mechanics, at equilibrium a system of electrons in a static magnetic field presents no magnetization. Thus a magnetization can occur only in an out of equilibrium state, such as that produced through the Foucault currents when a magnetic field is switched on. It was suggested by Bohr that, after the establishment of such a nonequilibrium state, the system of electrons would quickly relax back to equilibrium. In the present paper, we study numerically the relaxation to equilibrium in a modified Bohr model, which is mathematically equivalent to a billiard with obstacles, immersed in a magnetic field that is adiabatically switched on. We show that it is not guaranteed that equilibrium is attained within the typical time scales of microscopic dynamics. Depending on the values of the parameters, one has a relaxation either to equilibrium or to a diamagnetic (presumably metastable) state. The analogy with the relaxation properties in the Fermi Pasta Ulam problem is also pointed out.
Classical topology and quantum states
A P Balachandran
2001-02-01
Any two inﬁnite-dimensional (separable) Hilbert spaces are unitarily isomorphic. The sets of all their self-adjoint operators are also therefore unitarily equivalent. Thus if all self-adjoint operators can be observed, and if there is no further major axiom in quantum physics than those formulated for example in Dirac’s ‘quantum mechanics’, then a quantum physicist would not be able to tell a torus from a hole in the ground. We argue that there are indeed such axioms involving observables with smooth time evolution: they contain commutative subalgebras from which the spatial slice of spacetime with its topology (and with further reﬁnements of the axiom, its - and ∞ - structures) can be reconstructed using Gel’fand–Naimark theory and its extensions. Classical topology is an attribute of only certain quantum observables for these axioms, the spatial slice emergent from quantum physics getting progressively less differentiable with increasingly higher excitations of energy and eventually altogether ceasing to exist. After formulating these axioms, we apply them to show the possibility of topology change and to discuss quantized fuzzy topologies. Fundamental issues concerning the role of time in quantum physics are also addressed.
Structure of classical affine and classical affine fractional W-algebras
Suh, Uhi Rinn, E-mail: uhrisu1@math.snu.ac.kr [Department of Mathematical Sciences, Seoul National University, GwanAkRo 1, Gwanak-Gu, Seoul 151-747 (Korea, Republic of)
2015-01-15
We introduce a classical BRST complex (See Definition 3.2.) and show that one can construct a classical affine W-algebra via the complex. This definition clarifies that classical affine W-algebras can be considered as quasi-classical limits of quantum affine W-algebras. We also give a definition of a classical affine fractional W-algebra as a Poisson vertex algebra. As in the classical affine case, a classical affine fractional W-algebra has two compatible λ-brackets and is isomorphic to an algebra of differential polynomials as a differential algebra. When a classical affine fractional W-algebra is associated to a minimal nilpotent, we describe explicit forms of free generators and compute λ-brackets between them. Provided some assumptions on a classical affine fractional W-algebra, we find an infinite sequence of integrable systems related to the algebra, using the generalized Drinfel’d and Sokolov reduction.
Classic congenital adrenal hyperplasia: A delayed presentation
Aziz Siddiqui, Saima; Soomro, Nargis; Ganatra, Ashraf
2013-01-01
Congenital adrenal hyperplasia (CAH) is a rare congenital disorder, which in cases of female genotype may result in virilization. Specific enzyme deficiencies in adrenocorticoid hormones biosynthetic pathway lead to excess androgen production causing virilization. Classic type presents early in infant life as salt losing or simple virilizing type, whereas non classic form presents late at puberty or in adult life. Depending on the type of classic CAH, type of adrenocorticoid deficiency, exten...
Locking classical correlation in quantum states
Di Vincenzo, D P; Leung, D; Smolin, J A; Terhal, B M; Vincenzo, David Di; Horodecki, Michal; Leung, Debbie; Smolin, John; Terhal, Barbara
2003-01-01
We show that there exist bipartite quantum states which contain large hidden classical correlation that can be unlocked by a disproportionately small amount of classical communication. In particular, there are $(2n+1)$-qubit states for which a one bit message doubles the optimal classical mutual information between measurement results on the subsystems, from $n/2$ bits to $n$ bits. States exhibiting this behavior need not be entangled. We study the range of states exhibiting this phenomenon and bound its magnitude.
Classical information capacity of superdense coding
Bowen, G H
2001-01-01
Classical communication through quantum channels may be enhanced by sharing entanglement. Superdense coding allows the encoding, and transmission, of up to two classical bits of information in a single qubit. In this paper, the maximum classical channel capacity for states that are not maximally entangled is derived. Particular schemes are then shown to attain this capacity, firstly for pairs of qubits, and secondly for pairs of qutrits.
A critical review of classical bouncing cosmologies
Battefeld, Diana, E-mail: dbattefe@astro.physik.uni-goettingen.de [Institut for Astrophysics, University of Goettingen, Friedrich-Hund Platz 1, D-37077 (Germany); Peter, Patrick, E-mail: peter@iap.fr [Institut d’Astrophysique de Paris, UMR 7095-CNRS, Université Pierre et Marie Curie, 98 bis boulevard Arago, 75014 Paris (France)
2015-04-01
Given the proliferation of bouncing models in recent years, we gather and critically assess these proposals in a comprehensive review. The PLANCK data shows an unmistakably red, quasi scale-invariant, purely adiabatic primordial power spectrum and no primary non-Gaussianities. While these observations are consistent with inflationary predictions, bouncing cosmologies aspire to provide an alternative framework to explain them. Such models face many problems, both of the purely theoretical kind, such as the necessity of violating the NEC and instabilities, and at the cosmological application level, as exemplified by the possible presence of shear. We provide a pedagogical introduction to these problems and also assess the fitness of different proposals with respect to the data. For example, many models predict a slightly blue spectrum and must be fine-tuned to generate a red spectral index; as a side effect, large non-Gaussianities often result. We highlight several promising attempts to violate the NEC without introducing dangerous instabilities at the classical and/or quantum level. If primordial gravitational waves are observed, certain bouncing cosmologies, such as the cyclic scenario, are in trouble, while others remain valid. We conclude that, while most bouncing cosmologies are far from providing an alternative to the inflationary paradigm, a handful of interesting proposals have surfaced, which warrant further research. The constraints and lessons learned as laid out in this review might guide future research.
Primitive Ontology and the Classical World
Allori, Valia
In this chapter, I present the common structure of quantum theories with a primitive ontology (PO), and discuss in what sense the classical world emerges from quantum theories as understood in this framework. In addition, I argue that the PO approach is better at analyzing the classical limit than the rival wave function ontology approach or any other approach in which the classical world is non-reductively "emergent:" even if the classical limit within this framework needs to be fully developed, the difficulties are technical rather than conceptual, while this is not true for the alternatives.
On the tomographic description of classical fields
Ibort, A; Man'ko, V I; Marmo, G; Simoni, A; Sudarshan, E C G; Ventriglia, F
2012-01-01
After a general description of the tomographic picture for classical systems, a tomographic description of free classical scalar fields is proposed both in a finite cavity and the continuum. The tomographic description is constructed in analogy with the classical tomographic picture of an ensemble of harmonic oscillators. The tomograms of a number of relevant states such as the canonical distribution, the classical counterpart of quantum coherent states and a new family of so called Gauss--Laguerre states, are discussed. Finally the Liouville equation for field states is described in the tomographic picture offering an alternative description of the dynamics of the system that can be extended naturally to other fields.
Classical Fields and the Quantum Concept
De Souza, M M
1996-01-01
We do a critical review of the Faraday-Maxwell concept of classical field and of its quantization process. With the hindsight knowledge of the essentially quantum character of the interactions, we use a naive classical model of field, based on exchange of classical massless particles, for a comparative and qualitative analysis of the physical content of the Coulomb's and Gauss's laws. It enlightens the physical meaning of a field singularity and of a static field. One can understand the problems on quantizing a classical field but not the hope of quantizing the gravitational field right from General Relativity.
Seven Steps Towards the Classical World
Allori, V; Goldstein, S; Zanghì, N; Allori, Valia; Goldstein, Shelly; Zangh\\'{\\i}, Nino
2001-01-01
Classical physics is about real objects, like apples falling from trees, whose motion is governed by Newtonian laws. In standard Quantum Mechanics only the wave function or the results of measurements exist, and to answer the question of how the classical world can be part of the quantum world is a rather formidable task. However, this is not the case for Bohmian mechanics, which, like classical mechanics, is a theory about real objects. In Bohmian terms, the problem of the classical limit becomes very simple: when do the Bohmian trajectories look Newtonian?
Limitations on Cloning in Classical Mechanics
Fenyes, Aaron
2010-01-01
In this paper, we show that a result precisely analogous to the traditional quantum no-cloning theorem holds in classical mechanics. This classical no-cloning theorem does not prohibit classical cloning, we argue, because it is based on a too-restrictive definition of cloning. Using a less popular, more inclusive definition of cloning, we give examples of classical cloning processes. We also prove that a cloning machine must be at least as complicated as the object it is supposed to clone.
The safety of electrically assisted bicycles compared to classic bicycles.
Schepers, J P; Fishman, E; den Hertog, P; Wolt, K Klein; Schwab, A L
2014-12-01
Use of electrically assisted bicycles with a maximum speed of 25 km/h is rapidly increasing. This growth has been particularly rapid in the Netherlands, yet very little research has been conducted to assess the road safety implications. This case-control study compares the likelihood of crashes for which treatment at an emergency department is needed and injury consequences for electric bicycles to classic bicycles in the Netherlands among users of 16 years and older. Data were gathered through a survey of victims treated at emergency departments. Additionally, a survey of cyclists without any known crash experience, drawn from a panel of the Dutch population acted as a control sample. Logistic regression analysis is used to compare the risk of crashes with electric and classical bicycles requiring treatment at an emergency department. Among the victims treated at an emergency department we compared those being hospitalized to those being send home after the treatment at the emergency department to compare the injury consequences between electric and classical bicycle victims. The results suggest that, after controlling for age, gender and amount of bicycle use, electric bicycle users are more likely to be involved in a crash that requires treatment at an emergency department due to a crash. Crashes with electric bicycles are about equally severe as crashes with classic bicycles. We advise further research to develop policies to minimize the risk and maximize the health benefits for users of electric bicycles. Copyright © 2014 Elsevier Ltd. All rights reserved.
Fu, Jian
2010-01-01
We demonstrate that a tensor product structure could be obtained by introducing pseudorandom phase sequences into classical fields with two orthogonal modes. Using classical fields modulated with pseudorandom phase sequences, we discuss efficient simulation of several typical quantum states, including product state, Bell states, GHZ state, and W state. By performing quadrature demodulation scheme, we could obtain the mode status matrix of the simulating classical fields, based on which we propose a sequence permutation mechanism to reconstruct the simulated quantum states. The research on classical simulation of quantum states is important, for it not only enables potential practical applications in quantum computation, but also provides useful insights into fundamental concepts of quantum mechanics.
Quantization of light energy directly from classical electromagnetic theory in vacuum
She Wei-Long
2005-01-01
It is currently believed that light quantum or the quantization of light energy is beyond classical physics, and the picture of wave-particle duality, which was criticized by Einstein but has attracted a number of experimental researches, is necessary for the description of light. It is shown in this paper, however, that the quantization of light energy in vacuum, which is the same as that in quantum electrodynamics, can be derived directly from the classical electromagnetic theory through the consideration of statistics based on classical physics. Therefore, the quantization of energy is an intrinsic property of light as a classical electromagnetic wave and has no need of being related to particles.
Classical and semiclassical aspects of chemical dynamics
Gray, S.K.
1982-08-01
Tunneling in the unimolecular reactions H/sub 2/C/sub 2/ ..-->.. HC/sub 2/H, HNC ..-->.. HCN, and H/sub 2/CO ..-->.. H/sub 2/ + CO is studied with a classical Hamiltonian that allows the reaction coordinate and transverse vibrational modes to be considered directly. A combination of classical perturbation theory and the semiclassical WKB method allows tunneling probabilities to be obtained, and a statistical theory (RRKM) is used to construct rate constants for these reactions in the tunneling regime. In this fashion, it is found that tunneling may be important, particularly for low excitation energies. Nonadiabatic charge transfer in the reaction Na + I ..-->.. Na /sup +/ + I/sup -/ is treated with classical trajectories based on a classical Hamiltonian that is the analogue of a quantum matrix representation. The charge transfer cross section obtained is found to agree reasonably well with the exact quantum results. An approximate semiclassical formula, valid at high energies, is also obtained. The interaction of radiation and matter is treated from a classical viewpoint. The excitation of an HF molecule in a strong laser is described with classical trajectories. Quantum mechanical results are also obtained and compared to the classical results. Although the detailed structure of the pulse time averaged energy absorption cannot be reproduced classically, classical mechanics does predict the correct magnitude of energy absorption, as well as certain other qualitative features. The classical behavior of a nonrotating diatomic molecule in a strong laser field is considered further, by generating a period advance map that allows the solution over many periods of oscillation of the laser to be obtained with relative ease. Classical states are found to form beautiful spirals in phase space as time progresses. A simple pendulum model is found to describe the major qualitative features. (WHM)
Classical and semiclassical aspects of chemical dynamics
Gray, S.K.
1982-08-01
Tunneling in the unimolecular reactions H/sub 2/C/sub 2/ ..-->.. HC/sub 2/H, HNC ..-->.. HCN, and H/sub 2/CO ..-->.. H/sub 2/ + CO is studied with a classical Hamiltonian that allows the reaction coordinate and transverse vibrational modes to be considered directly. A combination of classical perturbation theory and the semiclassical WKB method allows tunneling probabilities to be obtained, and a statistical theory (RRKM) is used to construct rate constants for these reactions in the tunneling regime. In this fashion, it is found that tunneling may be important, particularly for low excitation energies. Nonadiabatic charge transfer in the reaction Na + I ..-->.. Na /sup +/ + I/sup -/ is treated with classical trajectories based on a classical Hamiltonian that is the analogue of a quantum matrix representation. The charge transfer cross section obtained is found to agree reasonably well with the exact quantum results. An approximate semiclassical formula, valid at high energies, is also obtained. The interaction of radiation and matter is treated from a classical viewpoint. The excitation of an HF molecule in a strong laser is described with classical trajectories. Quantum mechanical results are also obtained and compared to the classical results. Although the detailed structure of the pulse time averaged energy absorption cannot be reproduced classically, classical mechanics does predict the correct magnitude of energy absorption, as well as certain other qualitative features. The classical behavior of a nonrotating diatomic molecule in a strong laser field is considered further, by generating a period advance map that allows the solution over many periods of oscillation of the laser to be obtained with relative ease. Classical states are found to form beautiful spirals in phase space as time progresses. A simple pendulum model is found to describe the major qualitative features. (WHM)
Classical Swine Fever Virus-Rluc Replicons
Risager, Peter Christian; Belsham, Graham J.; Rasmussen, Thomas Bruun
Classical swine fever virus (CSFV) is the etiologic agent of the severe porcine disease, classical swine fever. Unraveling the molecular determinants of efficient replication is crucial for gaining proper knowledge of the pathogenic traits of this virus. Monitoring the replication competence within...
The Dance of Spain: Classical Folkloric Flamenco.
Gallant, Clifford J.
A text on the classical and folk dance of Spain includes a pretest, provided in both English and Spanish; text about the dance in general and the dance of Spain, both classical and folkloric; tests on the text, in both English and Spanish; more specific readings about the traditions of flamenco, castanets, and "el jaleo"; a glossary of…
Converting Projects from STK Classic to STK
Foucar, James G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2014-08-01
The version of STK (Sierra ToolKit) that has long been provided with Trilinos is no longer supported by the core develop- ment team. With the introduction of a the new STK library into Trilinos, the old STK has been renamed to stk classic. This document contains a rough guide of how to port a stk classic code to STK.
Milgram's Obedience Study: A Contentious Classic Reinterpreted
Griggs, Richard A.
2017-01-01
Given the many older criticisms of Milgram's obedience study and the more damning recent criticisms based on analyses of materials available in the Milgram archives at Yale, this study has become a contentious classic. Yet, current social psychology textbooks present it as an uncontentious classic, with no coverage of the recent criticisms and…
Why Do We See a Classical World?
Roemer, Hartmann
2011-01-01
From a general abstract system theoretical perspective, a quantum-like system description in the spirit of a generalized quantum theory may appear to be simpler and more natural than a classically inspired description. We investigate the reasons why we nevertheless conceive ourselves embedded into a classically structured world.
Climate Change and Classic Maya Water Management
Lucero, Lisa J; Gunn, Joel D; Scarborough, Vernon L
2011-01-01
.... We show not only how Classic Maya (ca. A.D. 250-950) society dealt with the annual seasonal extremes, but also how kings and farmers responded differently in the face of a series of droughts in the Terminal Classic period (ca. A.D. 800-950...
Isomorphic Formulae in Classical Propositional Logic
Dosen, K
2009-01-01
Isomorphism between formulae is defined with respect to categories formalizing equality of deductions in classical propositional logic and in the multiplicative fragment of classical linear propositional logic caught by proof nets. This equality is motivated by generality of deductions. Characterizations are given for pairs of isomorphic formulae, which lead to decision procedures for this isomorphism.
Cartledge, Paul
2005-01-01
Classics is in the news--or on the screen: "Gladiator" a few years ago, "Troy" very recently, "Alexander" as I write. How significant is this current Hollywood fascination with the ancient Greeks and Romans? Or should we take far more seriously the decline of the teaching of the Classical languages in schools, a…
Classical Conditioning: Eliciting the Right Response.
Tauber, Robert T.
1990-01-01
Classical conditioning is responsible for students' positive and negative feelings, whether directed toward subject matter, peers, teachers, or education in general. This article explains how educators can use classical conditioning principles (such as reinforcement, extinction, and paired stimuli) to create an anxiety-free learning environment.…
Factors Influencing the Learning of Classical Mechanics.
Champagne, Audrey B.; And Others
1980-01-01
Describes a study investigating the combined effect of certain variables on student achievement in classical mechanics. The purpose was to (1) describe preinstructional knowledge and skills; (2) correlate these variables with the student's success in learning classical mechanics; and (3) develop hypothesis about relationships between these…
Classical and Quantum-Mechanical State Reconstruction
Khanna, F. C.; Mello, P. A.; Revzen, M.
2012-01-01
The aim of this paper is to present the subject of state reconstruction in classical and in quantum physics, a subject that deals with the experimentally acquired information that allows the determination of the physical state of a system. Our first purpose is to explain a method for retrieving a classical state in phase space, similar to that…
Classical Music, liveness and digital technologies
Steijn, Arthur
2014-01-01
Performances of classical composition music have seen a decline in their audiences for some years. Does the classical concert ritual scare people off? This notion has spurred off a development of design concepts directed at rethinking concert rituals in order to create new audience experiences. T...
On entanglement-assisted classical capacity
Holevo, A. S.
2002-09-01
We give a modified proof of the recent result of C. H. Bennett, P. W. Shor, J. A. Smolin, and A. V. Thapliyal concerning entanglement-assisted classical capacity of a quantum channel and discuss the relation between entanglement-assisted and unassisted classical capacities.
New Classical and New Keynesian Macroeconomics.
Vane, Howard; Snowdon, Brian
1992-01-01
Summarizes underlying tenets and policy implications of new classical and new Keynesian macroeconomics. Compares new approaches with orthodox Keynesian and monetarist schools of thought. Identifies the fundamental difference between new classical and new Keynesian models as the assumption regarding the speed of wage and price adjustment following…
Classical decoherence in a nanomechanical resonator
Maillet, O.; Vavrek, F.; Fefferman, A. D.; Bourgeois, O.; Collin, E.
2016-07-01
Decoherence is an essential mechanism that defines the boundary between classical and quantum behaviours, while imposing technological bounds for quantum devices. Little is known about quantum coherence of mechanical systems, as opposed to electromagnetic degrees of freedom. But decoherence can also be thought of in a purely classical context, as the loss of phase coherence in the classical phase space. Indeed the bridge between quantum and classical physics is under intense investigation, using, in particular, classical nanomechanical analogues of quantum phenomena. In the present work, by separating pure dephasing from dissipation, we quantitatively model the classical decoherence of a mechanical resonator: through the experimental control of frequency fluctuations, we engineer artificial dephasing. Building on the fruitful analogy introduced between spins/quantum bits and nanomechanical modes, we report on the methods available to define pure dephasing in these systems, while demonstrating the intrinsic almost-ideal properties of silicon nitride beams. These experimental and theoretical results, at the boundary between classical nanomechanics and quantum information fields, are prerequisite in the understanding of decoherence processes in mechanical devices, both classical and quantum.