English
Related papers

Related papers: The near equilibrium Einstein-Boltzmann system wit…

200 papers

A collisional model of a confined quasi-two-dimensional granular mixture is considered to analyze homogeneous steady states. The model includes an effective mechanism to transfer the kinetic energy injected by vibration in the vertical…

Statistical Mechanics · Physics 2020-12-30 Ricardo Brito , Rodrigo Soto , Vicente Garzó

We study the condensate phase dynamics in a low-temperature equilibrium gas of weakly interacting bosons, harmonically trapped and isolated from the environment. We find that at long times, much longer than the collision time between…

Quantum Gases · Physics 2019-04-22 Yvan Castin , Alice Sinatra

Starting from Boltzmann equation with relaxation time approximation for the collision term and using Chapman-Enskog like expansion for distribution function close to equilibrium, we derive hydrodynamic evolution equations for the…

Nuclear Theory · Physics 2013-05-22 Amaresh Jaiswal

This paper is concerned with the analysis of polyatomic gases within the framework of kinetic theory. Internal degrees of freedom are modeled using a single continuous variable corresponding to the molecular internal energy. Non-equilibrium…

Mathematical Physics · Physics 2016-11-15 Milana Pavić-Čolić , Damir Madjarević , Srboljub Simić

An unified thermodynamical framework based in the use of a generalized Massieu-Planck thermodynamic potential is proposed and a new formulation of Boltzmann-Gibbs Statistical Mechanics is established. Under this philosophy a generalization…

Mathematical Physics · Physics 2007-05-23 V. Garcia-Morales , J. Pellicer

A covariant Fokker-Planck type equation for a simple gas and an equation for the Brownian motion are derived from a relativistic kinetic theory based on the Boltzmann equation. For the simple gas the dynamic friction four-vector and the…

Statistical Mechanics · Physics 2010-11-19 Guillermo Chacón--Acosta , Gilberto M. Kremer

Dynamics of inelastic gases are studied within the framework of random collision processes. The corresponding Boltzmann equation with uniform collision rates is solved analytically for gases, impurities, and mixtures. Generally, the energy…

Statistical Mechanics · Physics 2007-05-23 E. Ben-Naim , P. L. Krapivsky

The Borgnakke-Larsen model, widely used in rarefied flow predictions, serves as the mainstream energy-exchange kernel for polyatomic gases. However, it lacks integrability and does not guarantee detailed balance, limiting theoretical…

Computational Physics · Physics 2026-04-02 Sha Liu , Ningchao Ding , Ming Fang , Hao Jin , Rui Zhang , Congshan Zhuo , Chengwen Zhong

We describe an asymptotic procedure for deriving continuum equations from the kinetic theory of a simple gas. As in the works of Hilbert, of Chapman and of Enskog, we expand in the mean flight time of the constituent particles of the gas,…

Astrophysics · Physics 2009-11-06 Xinzhong Chen , Hongling Rao , Edward A. Spiegel

When the temperature of a trapped Bose gas is below the Bose-Einstein transition temperature and above absolute zero, the gas is composed of two distinct components: the Bose-Einstein condensate and the cloud of thermal excitations. The…

Analysis of PDEs · Mathematics 2021-07-09 Gheorghe Craciun , Minh-Binh Tran

The derivation of an approximate Class-I model for nonisothermal multicomponent systems of fluids, as the high-friction limit of a Class-II model is justified, by validating the Chapman-Enskog expansion performed from the Class-II model…

Analysis of PDEs · Mathematics 2024-05-24 Stefanos Georgiadis , Athanasios E. Tzavaras

Using recently developed consistent and robust first order relativistic hydrodynamics of a dissipative fluid we propose a generalization but weak version of Tolman-Ehrenfest relation and Klein's law on a general background spacetime. These…

General Relativity and Quantum Cosmology · Physics 2024-12-02 Bhera Ram , Bibhas Ranjan Majhi

We find a near detailed balance solution to the relativistic Boltzmann equation under the relaxation time approximation with a collision term which differs from the Anderson-Witting model and is dependent on the stationary observer. Using…

General Relativity and Quantum Cosmology · Physics 2022-12-08 Song Liu , Xin Hao , Shaofan Liu , Liu Zhao

A Lorentz gas may be defined as a system of fixed dispersing scatterers, with a single light particle moving among these and making specular collisions on encounters with the scatterers. For a dilute Lorentz gas with open boundaries in $d$…

Chaotic Dynamics · Physics 2009-11-10 Henk van Beijeren , Oliver Muelken

The de Sitter thermodynamics of cosmological models with a modified Friedmann equation is considered, with particular reference to high-energy Randall-Sundrum and Gauss-Bonnet braneworlds. The Friedmann equation can be regarded as the first…

High Energy Physics - Theory · Physics 2009-11-11 Gianluca Calcagni

We connect two different generalizations of Boltzmann's kinetic theory by requiring the same stationary solution. Non-extensive statistics can be produced by either using corresponding collision rates nonlinear in the one-particle densities…

Statistical Mechanics · Physics 2009-11-11 T. S. Biro , G. Kaniadakis

In this paper we complete the program initiated by the first and second authors and rigorously derive a Boltzmann-type equation that incorporates higher order collisions among gas particles. More precisely, starting from a finite…

Analysis of PDEs · Mathematics 2024-09-11 Ioakeim Ampatzoglou , Nataša Pavlović , William Warner

In the Hermite-expansion-based multiple-relaxation-time lattice Boltzmann (LB) model [Shan & Chen, Int. J. Mod. Phys. C, 18, 635, (2007)], a separate relaxation time is assigned to each of the tensorial moments of the collision term. Here…

Computational Physics · Physics 2021-05-05 Xuhui Li , Xiaowen Shan

A novel pedagogical technique is presented that can be used in the undergraduate (UG) class to formulate a relativistically extended Kinetic Theory of Gases and thermal speed distribution, while assuming the basic thermal symmetry arguments…

General Physics · Physics 2015-03-20 Ashmeet Singh

We show how using a special relativistic kinetic equation with a BGK- like collision operator the ensuing expression for the heat flux can be casted in the form required by Classical Irreversible Thermodynamics. Indeed, it is linearly…

General Relativity and Quantum Cosmology · Physics 2009-06-12 A. Sandoval-Villalbazo , A. L. Garcia-Perciante , L. S. Garcia-Colin