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Related papers: A simple semiclassical approach to Kramers' proble…

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In this paper we derive a fully relativistic kinetic theory for spin-1/2 particles and its coupling to Maxwell's equations, valid in the long scale-length limit, where the fields vary on a scale much longer than the localization of the…

Plasma Physics · Physics 2017-08-30 Robin Ekman , Felipe A. Asenjo , Jens Zamanian

Viewed as approximations to quantum mechanics, classical evolutions can violate the positive-semidefiniteness of the density matrix. The nature of this violation suggests a classification of dynamical systems based on classical-quantum…

Quantum Physics · Physics 2009-11-06 Salman Habib , Kurt Jacobs , Hideo Mabuchi , Robert Ryne , Kosuke Shizume , Bala Sundaram

We use the semi-classical approximation in perturbative scalar quantum electrodynamics to calculate the quantum correction to the Larmor radiation formula to first order in Planck's constant in the non-relativistic approximation, choosing…

High Energy Physics - Theory · Physics 2013-05-29 A. Higuchi , P. J. Walker

Time-symmetric quantum mechanics can be described in the usual Weyl--Wigner--Moyal formalism (WWM) by using the properties of the Wigner distribution, and its generalization, the cross-Wigner distribution. The use of the latter makes clear…

Quantum Physics · Physics 2015-10-12 Charlyne de Gosson , Maurice de Gosson

We develop a functional analytic approach to the study of the Kramers and kinetic Fokker-Planck equations which parallels the classical $H^1$ theory of uniformly elliptic equations. In particular, we identify a function space analogous to…

Analysis of PDEs · Mathematics 2024-07-24 D. Albritton , S. Armstrong , J. -C. Mourrat , M. Novack

The phase-space path-integral approach to the damped harmonic oscillator is analyzed beyond the Markovian approximation. It is found that pairs of nonclassical trajectories contribute to the path-integral representation of the Wigner…

Quantum Physics · Physics 2010-10-07 Leonardo A. Pachon , Gert-Ludwig Ingold , Thomas Dittrich

We give a partial answer to the question whether the Schrodinger equation can be derived from the Newtonian mechanics of a particle in a potential subject to a random force. We show that the fluctuations around the classical motion of a one…

Quantum Physics · Physics 2021-02-24 Can Gokler

Semiclassical approximations for various representations of a quantum state are constructed on a single (Lagrangian) surface in phase space, but it is not available for chaotic systems. An analogous evolution surface underlies semiclassical…

Quantum Physics · Physics 2025-07-11 Alfredo M. Ozorio de Almeida

Wigner's quasi-probability distribution function in phase-space is a special (Weyl) representation of the density matrix. It has been useful in describing quantum transport in quantum optics; nuclear physics; decoherence (eg, quantum…

High Energy Physics - Theory · Physics 2008-11-26 Cosmas K Zachos

We demonstrate a method which allows the stochastic modelling of quantum systems for which the generalised Fokker-Planck equation in the phase space contains derivatives of higher than second order. This generalises quantum stochastics far…

Quantum Physics · Physics 2009-11-07 L. I. Plimak , M. K. Olsen , M. Fleischhauer , M. J. Collett

We analyze the tunneling of a particle through a repulsive potential resulting from an inverted harmonic oscillator in the quantum mechanical phase space described by the Wigner function. In particular, we solve the partial differential…

Quantum Physics · Physics 2013-06-07 D. M. Heim , W. P. Schleich , P. M. Alsing , J. P. Dahl , S. Varro

We propose a semiclassical approach to calculate multiparticle cross sections in scalar theories, which have been strongly argued to have the exponential form $\exp(\lambda^{-1}F(\lambda n,\epsilon))$ in the regime $\lambda\to0$, $\lambda…

High Energy Physics - Phenomenology · Physics 2008-02-03 D. T. Son

The quantum dynamics of an electron in a uniform magnetic field is studied for geometries corresponding to integrable cases. We obtain the uniform asymptotic approximation of the WKB energies and wavefunctions for the semi-infinite plane…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 D. Spehner , R. Narevich , E. Akkermans

We show how a large family of master equations, describing quantum Brownian motion of a harmonic oscillator with translationally invariant damping, can be derived within a phenomenological approach, based on the assumption that an…

Quantum Physics · Physics 2009-11-13 A. V. Dodonov , S. S. Mizrahi , V. V. Dodonov

We follow and modify the Feshbach-Villars formalism by separating the Klein-Gordon equation into two coupled time-dependent Schroedinger equations for particle and antiparticle wave function components with positive probability densities.…

High Energy Physics - Phenomenology · Physics 2011-08-04 Cheuk-Yin Wong

We employ the Wigner function formalism to simulate partially coherent, dissipative electron transport in biased semiconductor superlattices. We introduce a model collision integral with terms that describe energy dissipation, momentum…

Mesoscale and Nanoscale Physics · Physics 2015-10-26 O. Jonasson , I. Knezevic

The recently developed quantum surface of section method is applied to a search for extremely high-lying energy levels in a simple but generic Hamiltonian system between integrability and chaos, namely the semiseparable 2-dim oscillator.…

chao-dyn · Physics 2009-10-28 Tomaz Prosen

It is shown that charged-particle beam transport in the paraxial approximation can be effectively described with a quantum-like picture in semiclassical approximation. In particular, the classical Liouville equation can be suitably replaced…

Quantum Physics · Physics 2007-05-23 R. Fedele , V. I. Man'ko

In this article we try to bridge the gap between the quantum dynamical semigroup and Wigner function approaches to quantum open systems. In particular we study stationary states and the long time asymptotics for the quantum Fokker-Planck…

Mathematical Physics · Physics 2008-10-22 Anton Arnold , Franco Fagnola , Lukas Neumann

Starting from the Schr\"odinger-equation of a composite system, we derive unified dynamics of a classical harmonic system coupled to an arbitrary quantized system. The classical subsystem is described by random phase-space coordinates…

Quantum Physics · Physics 2007-05-23 Lajos Diosi
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