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Coulomb collision is a fundamental diffusion process in plasmas that can be described by the Landau-Fokker-Planck (LFP) equation or the stochastic differential equation (SDE). While energy and momentum are conserved exactly in the LFP…

Plasma Physics · Physics 2025-03-05 Yichen Fu , Justin R. Angus , Hong Qin , Vasily I. Geyko

In this work, the asymptotic state of nonlinear Landau damping in one-dimensional plasma has been examined using a quasi-linear model and a second-order symplectic integrator. The dispersion relation of the plateau distribution function for…

Plasma Physics · Physics 2025-12-22 Yifei Ouyang , Ping Zhu , Chung-Sang Ng

Collisionless damping of electrical waves in plasma is investigated in the frame of the classical formulation of the problem. The new principle of regularization of the singular integral is used. The exact solution of the corresponding…

Statistical Mechanics · Physics 2008-08-01 Boris V. Alexeev

We investigate the old problem of the fast relaxation of collisionless $N$-body systems which are collapsing or perturbed, emphasizing the importance of (non-collisional) discreteness effects. We integrate orbit ensembles in fixed external…

Astrophysics of Galaxies · Physics 2019-01-30 Leandro Beraldo e Silva , Walter de Siqueira Pedra , Monica Valluri , Laerte Sodré , Jean-Bernard Bru

We use the Hamiltonian formulation of kinetic theory to perform a stability analysis of non-thermal fixed points in a non-Abelian plasma. We construct a perturbative expansion of the Fokker-Planck collision kernel in an adiabatic…

High Energy Physics - Phenomenology · Physics 2022-07-01 Aleksandr N. Mikheev , Aleksas Mazeliauskas , Jürgen Berges

We develop a comprehensive Hamiltonian formulation for plasma dynamics that unifies collisionless gyrokinetic and collisional processes. Our framework rigorously describes the evolution of free energy and entropy during the transition from…

Plasma Physics · Physics 2025-07-08 Joseph Samper Finberg

We consider a system of particles subjected to a uniform external force E and undergoing random collisions with "virtual" fixed obstacles, as in the Drude model of conductivity. The system is maintained in a nonequilibrium stationary state…

Chaotic Dynamics · Physics 2016-12-21 Federico Bonetto , Joel L. Lebowitz

We consider the asymmetric simple exclusion process with Langmuir kinetics on a periodic lattice. We analytically obtain the exact time evolution of correlation functions with arbitrary length starting from the initial state with no…

Statistical Mechanics · Physics 2016-04-20 Jun Sato , Katsuhiro Nishinari

We prove the existence and uniqueness of an equilibrium state with unit mass to the dissipative linear Boltzmann equation with hard--spheres collision kernel describing inelastic interactions of a gas particles with a fixed background. The…

Statistical Mechanics · Physics 2009-11-10 Bertrand Lods , Giuseppe Toscani

We study, globaly in time, the velocity distribution $f(v,t)$ of a spatially homogeneous system that models a system of electrons in a weakly ionized plasma, subjected to a constant external electric field $E$. The density $f$ satisfies a…

Plasma Physics · Physics 2009-10-30 E. Carlen , R. Esposito , J. L. Lebowitz , R. Marra , A. Rokhlenko

We study the low-energy collective oscillations of a dilute Bose gas at finite temperature in the collisionless regime. By using a time-dependent mean-field scheme we derive for the dynamics of the condensate and noncondensate components a…

Condensed Matter · Physics 2009-10-31 S. Giorgini

The phase space of a noncanonical Hamiltonian system is partially inaccessible due to dynamical constraints (Casimir invariants) arising from the kernel of the Poisson tensor. When an ensemble of noncanonical Hamiltonian systems is allowed…

Statistical Mechanics · Physics 2024-05-20 Naoki Sato , Philip J. Morrison

The lattice Boltzmann equation (LBE), rooted in kinetic theory, provides a powerful framework for capturing complex flow behaviour by describing the evolution of single-particle distribution functions (PDFs). Despite its success, solving…

Collisional relaxation of Coulomb systems is studied in the strongly coupled regime. We use an optical pump-probe approach to manipulate and monitor the dynamics of ions in an ultracold neutral plasma, which allows direct measurement of…

Plasma Physics · Physics 2013-02-26 G. Bannasch , J. Castro , P. McQuillen , T. Pohl , T. C. Killian

The lattice Boltzmann method (LBM) is known to suffer from stability issues when the collision model relies on the BGK approximation, especially in the zero viscosity limit and for non-vanishing Mach numbers. To tackle this problem, two…

Computational Physics · Physics 2020-06-09 C. Coreixas , G. Wissocq , B. Chopard , J. Latt

We study a phenomenological dark matter model described as a collisionless relativistic kinetic gas in a spatially flat Friedmann-Lema\^itre-Robertson-Walker universe. After normalization to the observed present-day dark matter abundance,…

General Physics · Physics 2026-02-10 Francisco X. Linares Cedeño , Ulises Nucamendi , Olivier Sarbach

Going beyond the linearized study has been a longstanding problem in the theory of Landau damping. In this paper we establish exponential Landau damping in analytic regularity. The damping phenomenon is reinterpreted in terms of transfer of…

Analysis of PDEs · Mathematics 2012-02-22 Clément Mouhot , Cédric Villani

We discuss the dynamics and thermodynamics of systems with long-range interactions. We contrast the microcanonical description of an isolated Hamiltonian system to the canonical description of a stochastically forced Brownian system. We…

Statistical Mechanics · Physics 2009-11-10 Pierre-Henri Chavanis

We consider a kinetic model whose evolution is described by a Boltzmann-like equation for the one-particle phase space distribution $f(x,v,t)$. There are hard-sphere collisions between the particles as well as collisions with randomly fixed…

Mathematical Physics · Physics 2020-01-08 Raffaele Esposito , Pedro G. Garrido , Joel L. Lebowitz , Rossana Marra

The current paradigm for understanding galaxy formation in the universe depends on the existence of self-gravitating collisionless dark matter. Modeling such dark matter systems has been a major focus of astrophysicists, with much of that…

Astrophysics of Galaxies · Physics 2015-06-17 Eric I. Barnes , Robert J. Ragan