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Related papers: Spin relaxation in phase space

200 papers

Two-frequency Wigner distribution is introduced to capture the asymptotic behavior of the space-frequency correlation of paraxial waves in the radiative transfer limits. The scaling limits give rises to deterministic transport-like…

Optics · Physics 2015-06-26 Albert C. Fannjiang

Quantum devices are preparing increasingly more complex entangled quantum states. How can one effectively study these states in light of their increasing dimensions? Phase spaces such as Wigner functions provide a suitable framework. We…

Quantum Physics · Physics 2021-01-04 Bálint Koczor , Robert Zeier , Steffen J. Glaser

We introduce a quantum phase space representation for the orientation state of extended quantum objects, using the Euler angles and their conjugate momenta as phase space coordinates. It exhibits the same properties as the standard Wigner…

Quantum Physics · Physics 2013-06-11 Timo Fischer , Clemens Gneiting , Klaus Hornberger

The continued-fraction method to solve classical Fokker--Planck equations has been adapted to tackle quantum master equations of the Caldeira--Leggett type. This can be done taking advantage of the phase-space (Wigner) representation of the…

Statistical Mechanics · Physics 2007-05-23 J. L. Garcia-Palacios , D. Zueco

Following the discussion -- in state space language -- presented in a preceding paper, we work on the passage from the phase space description of a degree of freedom described by a finite number of states (without classical counterpart) to…

Quantum Physics · Physics 2009-11-07 M. Ruzzi , D. Galetti

The extension of the phase-space Weyl-Wigner quantum mechanics to the subset of Hamiltonians in the form of $H(q,\,p) = {K}(p) + {V}(q)$ (with $K(p)$ replacing single $p^2$ contributions) is revisited. Deviations from classical and…

Quantum Physics · Physics 2024-09-09 Alex E. Bernardini , Orfeu Bertolami

The Wigner function formalism has been applied to the analysis of elastic scattering processes. The new element of known formalism is the choice of the phase space on which the Wigner function is defined. This phase space is 4-dimensional…

High Energy Physics - Phenomenology · Physics 2010-08-09 I. Perevalova , M. Polyakov , O. Soldatenko , A. Vall

We represent both the states and the evolution of a quantum computer in phase space using the discrete Wigner function. We study properties of the phase space representation of quantum algorithms: apart from analyzing important examples,…

Quantum Physics · Physics 2009-11-07 Cesar Miquel , Juan Pablo Paz , Marcos Saraceno

We implement the so-called Weyl-Heisenberg covariant integral quantization in the case of a classical system constrained by a bounded or semi-bounded geometry. The procedure, which is free of the ordering problem of operators, is…

Quantum Physics · Physics 2019-11-04 J. -P. Gazeau , T. Koide , D. Noguera

The physical phase space of gauge field theories on a cylindrical spacetime with an arbitrary compact simple gauge group is shown to be the quotient $ {\bf R}^{2r}/W_A, $ $ r $ a rank of the gauge group, $ W_A $ the affine Weyl group. The…

High Energy Physics - Theory · Physics 2009-10-22 Sergey V. Shabanov

The paper develop the alternative formulation of quantum mechanics known as the phase space quantum mechanics or deformation quantization. It is shown that the quantization naturally arises as an appropriate deformation of the classical…

Mathematical Physics · Physics 2011-09-27 Maciej Blaszak , Ziemowit Domanski

A general relation between the Moyal formalisms for a spin and a particle is established. Once the formalism has been set up for a spin, the phase-space description of a particle is obtained from the `contraction' of the group of rotations…

Quantum Physics · Physics 2009-11-06 Jean-Pierre Amiet , Stefan Weigert

The mixed density operator for coarsegrained eigenlevels of a static Hamiltonian is represented in phase space by the spectral Wigner function, which has its peak on the corresponding classical energy shell. The action of trajectory…

Quantum Physics · Physics 2024-03-05 Alfredo M. Ozorio de Almeida

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

We propose fractional Fokker-Planck equation for the kinetic description of relaxation and superdiffusion processes in constant magnetic and random electric fields. We assume that the random electric field acting on a test charged particle…

Plasma Physics · Physics 2009-11-07 A. Chechkin , V. Gonchar , M. Szydlowski

The conventional phase space of classical physics treats space and time differently, and this difference carries over to field theories and quantum mechanics (QM). In this paper, the phase space is enhanced through two main extensions.…

Quantum Physics · Physics 2024-05-15 N. L. Diaz , J. M. Matera , R. Rossignoli

Here we argue that spinor structure arises naturally if relativistic statistical mechanics is formulated directly on phase spacetime. Requiring a first-order phase-spacetime description that retains both mass-shell branches leads to a…

Quantum Physics · Physics 2026-05-19 Mark J. Everitt

The Fokker-Planck equation describing the transport of energetic particles interacting with turbulence is difficult to solve analytically. Numerical solutions are of course possible but they are not always useful for applications. In the…

Solar and Stellar Astrophysics · Physics 2025-04-29 B. Klippenstein , A. Shalchi

We study the phase-space concentration of the so-called generalized metaplectic operators whose main examples are Schr\"odinger equations with bounded perturbations. To reach this goal, we perform a so-called $\mathcal{A}$-Wigner analysis…

Analysis of PDEs · Mathematics 2022-09-15 Elena Cordero , Gianluca Giacchi , Luigi Rodino

In quantum mechanics, systems can be described in phase space in terms of the Wigner function and the star-product operation. Quantum characteristics, which appear in the Heisenberg picture as the Weyl's symbols of operators of canonical…

Nuclear Theory · Physics 2011-07-19 M. I. Krivoruchenko , C. Fuchs , Amand Faessler