English
Related papers

Related papers: Collisionless Relaxation in Galactic Dynamics and …

200 papers

A linear Boltzmann equation with nonautonomous collision operator is rigorously derived in the Boltzmann-Grad limit for the deterministic dynamics of a Rayleigh gas where a tagged particle is undergoing hard-sphere collisions with…

Analysis of PDEs · Mathematics 2019-04-24 Karsten Matthies , George Stone

We review and complete the kinetic theory of spatially inhomogeneous stellar systems when collective effects (dressing of the stars by their polarization cloud) are neglected. We start from the BBGKY hierarchy issued from the Liouville…

Astrophysics of Galaxies · Physics 2015-06-11 Pierre-Henri Chavanis

Systems of particles with long range interactions present two important processes: first, the formation of out-of-equilibrium quasi-stationary states (QSS), and the collisional relaxation towards Maxwell-Boltzmann equilibrium in a much…

Statistical Mechanics · Physics 2017-03-08 Fernanda P. C. Benetti , Bruno Marcos

Landau damping/growing at boundary condition of excitation of a harmonic wave in collisionless ion-electron-neutrals plasma contradicts to the law of energy conservation of a wave damping/growing in space. There is also no criterion of a…

General Physics · Physics 2015-09-11 V. N. Soshnikov

The real time evolution of field condensates with soft length scales k^{-1}>(eT)^{-1} is solved in hot scalar electrodynamics, with a view towards understanding relaxational phenomena in the QGP and the electroweak plasma. We find that…

High Energy Physics - Phenomenology · Physics 2011-04-15 Daniel Boyanovsky , Hector J. de Vega , Richard Holman , S. Prem Kumar , Robert D. Pisarski

In this paper, we present our conclusions from the numerical study of the collapse of a destabilized collisionless stellar system. We use both direct integration of the Vlasov-Poisson equations and an N-body tree code to obtain our results,…

Astrophysics · Physics 2009-11-07 Thomas E. C. Merrall , Richard N. Henriksen

This work is devoted to the analysis of the linear Boltzmann equation in a bounded domain, in the presence of a force deriving from a potential. The collision operator is allowed to be degenerate in the following two senses: (1) the…

Analysis of PDEs · Mathematics 2014-02-03 Daniel Han-Kwan , Matthieu Léautaud

In these lecture notes I review the theory of the non--linear evolution of cosmological perturbations in a self--gravitating collisionless medium, with vanishing vorticity. The problem is first analyzed in the context of the Newtonian…

Astrophysics · Physics 2015-06-24 Sabino Matarrese

Motivated by the recent interest in non-equilibrium phenomena in quantum many-body systems, we study strongly interacting fermions on a lattice by deriving and numerically solving quantum Boltzmann equations that describe their relaxation…

Quantum Physics · Physics 2019-12-10 Friedemann Queisser , Sebastian Schreiber , Peter Kratzer , Ralf Schützhold

This article is devoted to the long-time dynamics of point-vortex type systems near thermal equilibrium and to the possible emergence of collisional relaxation. More precisely, we consider a tagged particle coupled to a large number of…

Analysis of PDEs · Mathematics 2025-10-15 Mitia Duerinckx , Pierre-Emmanuel Jabin

We review and complete the existing literature on the kinetic theory of spatially homogeneous systems with long-range interactions taking collective effects into account. The evolution of the system as a whole is described by the…

Statistical Mechanics · Physics 2012-02-20 Pierre-Henri Chavanis

In this Letter, we investigate the stability of the statistical equilibrium of spherically symmetric collisionless self-gravitating systems. By calculating the second variation of the entropy, we find that perturbations of the relevant…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-08 Ping He , Dong-Biao Kang

Quasistationary states are long-lived nonequilibrium states, observed in some systems with long-range interactions under deterministic Hamiltonian evolution. These intriguing non-Boltzmann states relax to equilibrium over times which…

Statistical Mechanics · Physics 2015-03-17 Shamik Gupta , David Mukamel

Theory and simulations are used to study collisionless relaxation of a gravitational $N$-body system. It is shown that when the initial one particle distribution function satisfies the virial condition -- potential energy is minus twice the…

Statistical Mechanics · Physics 2008-08-25 Yan Levin , Renato Pakter , Felipe B. Rizzato

Violent relaxation during the collapse of a galaxy halo is known to be incomplete in realistic cases such as cosmological infall or mergers. We adopt a physical picture of strong but short lived interactions between potential fluctuations…

Astrophysics · Physics 2009-10-31 A. Mangalam , R. Nityananda , S. Sridhar

In systems removed from equilibrium, intrinsic microscopic fluctuations become correlated over distances comparable to the characteristic macroscopic length over which the external constraint is exerted. In order to investigate this…

comp-gas · Physics 2009-10-28 Alberto Suarez , Jean Pierre Boon , Patrick Grosfils

The early dynamics in heavy-ion collisions involves a rapid, far from equilibrium evolution. This early pre-equilibrium stage of the dynamics can be modeled using kinetic equations. The effect of this pre-equilibrium stage on final…

Nuclear Theory · Physics 2023-04-05 Piotr Bozek

Dense stellar systems such as globular clusters, galactic nuclei and nuclear star clusters are ideal loci to study stellar dynamics due to the very high densities reached, usually a million times higher than in the solar neighborhood; they…

Astrophysics of Galaxies · Physics 2015-05-19 Justus Schneider , Pau Amaro-Seoane , Rainer Spurzem

The main goal of this paper is to set up a numerical laboratory for the study of the slow evolution of the density and of the pressure tensor profiles of an otherwise collisionless stellar system, as a result of the interactions with a…

Astrophysics · Physics 2009-11-07 G. Bertin , T. Liseikina , F. Pegoraro

This paper investigates the dynamics of cosmological models incorporating nonlinear electrodynamics (NLED), focusing on their stability and causality. We explore two specific NLED models: the Power-Law and Rational Lagrangians. We assess…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-05 Ricardo García-Salcedo , Isidro Gómez-Vargas , Tame González , Vicent Martinez-Badenes , Israel Quiros