English
Related papers

Related papers: What is semiquantum mechanics?

200 papers

Quantum mechanics has been formulated in phase space, with the Wigner function as the representative of the quantum density operator, and classical mechanics has been formulated in Hilbert space, with the Groenewold operator as the…

Quantum Physics · Physics 2017-02-23 A. J. Bracken , J. G. Wood

Classical mechanics is formulated in complex Hilbert space with the introduction of a commutative product of operators, an antisymmetric bracket, and a quasidensity operator. These are analogues of the star product, the Moyal bracket, and…

Quantum Physics · Physics 2017-02-23 A. J. Bracken

Quantum states can be described equivalently by density matrices, Wigner functions or quantum tomograms. We analyze the accuracy and performance of three related semiclassical approaches to quantum dynamics, in particular with respect to…

Quantum Physics · Physics 2009-08-27 G. Schubert , V. S. Filinov , K. Matyash , R. Schneider , H. Fehske

The time evolution of the Wigner function for Gaussian states generated by Lindblad quantum dynamics is investigated in the semiclassical limit. A new type of phase-space dynamics is obtained for the centre of a Gaussian Wigner function,…

Quantum Physics · Physics 2019-02-01 E M Graefe , B Longstaff , T Plastow , R Schubert

In loop quantum cosmology the quantum dynamics is well understood. We approximate the full quantum dynamics in the infinite dimensional Hilbert space by projecting it on a finite dimensional submanifold thereof, spanned by suitably chosen…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Victor Taveras

A semiclassical approximation is derived by using a family of wavepackets to map arbitrary wavefunctions into phase space. If the Hamiltonian can be approximated as linear over each individual wavepacket, as often done when presenting…

Quantum Physics · Physics 2024-04-30 Clay D. Spence

The Weyl-Wigner representation of quantum mechanics allows one to map the density operator in a function in phase space - the Wigner function - which acts like a probability distribution. In the context of statistical mechanics, this…

Quantum Physics · Physics 2023-08-31 Marcos Gil de Oliveira , Alfredo Miguel Ozorio de Almeida

Deterministic dynamical models are discussed which can be described in quantum mechanical terms. In particular, a local quantum field theory is presented which is a supersymmetric classical model. -- The Hilbert space approach of Koopman…

High Energy Physics - Theory · Physics 2007-05-23 Hans-Thomas Elze

Quantum mechanics can be formulated in terms of phase-space functions, according to Wigner's approach. A generalization of this approach consists in replacing the density operators of the standard formulation with suitable functions, the…

Mathematical Physics · Physics 2015-06-17 Paolo Aniello

The semiclassically scaled time-dependent multi-particle Schr\"odinger equation describes, inter alia, quantum dynamics of nuclei in a molecule. It poses the combined computational challenges of high oscillations and high dimensions. This…

Numerical Analysis · Mathematics 2020-12-02 Caroline Lasser , Christian Lubich

The semiclassical approximation of coherent state path integrals is employed to study the dynamics of the Jaynes-Cummings model. Decomposing the Hilbert space into subspaces of given excitation quanta above the ground state, the…

Quantum Physics · Physics 2009-11-06 Adrian Alscher , Hermann Grabert

In this first of a series of four articles, it is shown how a hamiltonian quantum dynamics can be formulated based on a generalization of classical probability theory using the notion of quasi-invariant measures on the classical phase space…

High Energy Physics - Theory · Physics 2008-08-13 S. Maxson

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

The dynamics of a quantum system following a sudden, highly non-adiabatic change of its control parameter (quantum quench) is studied with quasiclassical techniques. Recent works have shown, using exact quantum mechanical approach, that…

An initial coherent state is propagated exactly by a kicked quantum Hamiltonian and its associated classical stroboscopic map. The classical trajectories within the initial state are regular for low kicking strengths, then bifurcate and…

Chaotic Dynamics · Physics 2019-07-16 Gabriel M. Lando , Alfredo M. Ozorio de Almeida

We investigate quasi-hermitian quantum mechanics in phase space using standard deformation quantization methods: Groenewold star products and Wigner transforms. We focus on imaginary Liouville theory as a representative example where exact…

Quantum Physics · Physics 2008-11-26 Thomas Curtright , Andrzej Veitia

Semiclassical Mechanics allows for a description of quantum systems which preserves their phase information, while using only the system's classical dynamics as an input. Over the time an identification has been developed between stationary…

Quantum Physics · Physics 2021-02-16 Kush Mohan Mittal , Olivier Giraud , Denis Ullmo

We extend the Wigner-Weyl-Moyal phase-space formulation of quantum mechanics to general curved configuration spaces. The underlying phase space is based on the chosen coordinates of the manifold and their canonically conjugate momenta. The…

Quantum Physics · Physics 2023-02-07 Clemens Gneiting , Timo Fischer , Klaus Hornberger

The trace of an arbitrary product of quantum operators with the density operator is rendered as a multiple phase space integral of the product of their Weyl symbols with the Wigner function. Interspersing the factors with various evolution…

Quantum Physics · Physics 2016-04-20 Alfredo M. Ozorio de Almeida , Olivier Brodier

A "quasiclassical" approximation to the quantum spectrum of the Schroedinger equation is obtained from the trace of a quasiclassical evolution operator for the "hydrodynamical" version of the theory, in which the dynamical evolution takes…

chao-dyn · Physics 2009-10-28 Predrag Cvitanovic , Gabor Vattay , Andreas Wirzba
‹ Prev 1 2 3 10 Next ›