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Related papers: Boltzmann equation and its cosmological applicatio…

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We have presented first an axiomatic derivation of Boltzmann entropy on the basis of two axioms consistent with two basic properties of thermodynamic entropy. We have then studied the relationship between Boltzmann entropy and information…

General Physics · Physics 2007-12-22 C. G. Chakrabarti , Indranil Chakrabarty

We present a novel method to solve the spatially homogeneous and isotropic relativistic Boltzmann equation. We employ a basis set of orthogonal polynomials dynamically adapted to allow for emergence of chemical non-equilibrium. Two time…

Numerical Analysis · Mathematics 2015-06-19 Jeremiah Birrell , Jon Wilkening , Johann Rafelski

We argue that one can model deviations from the ensemble average in non-equilibrium statistical mechanics by promoting the Boltzmann equation to an equation in terms of {\em functionals} , representing possible candidates for phase space…

Statistical Mechanics · Physics 2024-03-13 Giorgio Torrieri

We study the abundance of a particle species in a thermalized plasma by introducing a quantum kinetic description based on the non-equilibrium effective action. A stochastic interpretation of quantum kinetics in terms of a Langevin equation…

High Energy Physics - Phenomenology · Physics 2009-11-10 D. Boyanovsky , K. Davey , C. M. Ho

We consider a linear Boltzmann equation that arises in a model for quantum friction. It describes a particle that is slowed down by the emission of bosons. We study the stochastic process generated by this Boltzmann equation and we show…

Mathematical Physics · Physics 2024-04-25 Roland Bauerschmidt , Wojciech de Roeck , Jürg Fröhlich

Derivation of the canonical (or Boltzmann) distribution based only on quantum dynamics is discussed. Consider a closed system which consists of mutually interacting subsystem and heat bath, and assume that the whole system is initially in a…

Statistical Mechanics · Physics 2009-10-30 Hal Tasaki

Collisional effects are included in the path-integral formulation that was proposed in one of our previous paper for the collisionless Boltzmann gas. In calculating the number of molecules entering a six-dimensional phase volume element due…

Fluid Dynamics · Physics 2007-05-23 C. Y. Chen

Traditional computations of the dark matter (DM) relic abundance, for models where attractive self-interactions are mediated by light force-carriers and bound states exist, rely on the solution of a coupled system of classical on-shell…

High Energy Physics - Phenomenology · Physics 2018-12-26 Tobias Binder , Laura Covi , Kyohei Mukaida

Dark energy and dark matter are two of the biggest mysteries of modern cosmology, and our understanding of their fundamental nature is incomplete. Many parameterizations of couplings between the two in the continuity equation have been…

General Relativity and Quantum Cosmology · Physics 2021-06-25 Kevin J. Ludwick , Holston Sebaugh

A dynamical estimate is given for the Boltzmann entropy of the Universe, under the simplifying assumptions provided by Newtonian cosmology. We first model the cosmological fluid as the probability fluid of a quantum-mechanical system. Next,…

Quantum Physics · Physics 2023-07-19 D. Cabrera , P. Fernandez de Cordoba , J. M. Isidro

In this paper, we study the polyatomic Boltzmann equation based on continuous internal energy, focusing on physically relevant collision kernels of the hard potentials type with integrable angular part. We establish three main results:…

Analysis of PDEs · Mathematics 2025-10-14 Ricardo Alonso , Milana Čolić

Kinetic theories constitute one of the most promising tools to decipher the characteristic spatio-temporal dynamics in systems of actively propelled particles. In this context, the Boltzmann equation plays a pivotal role, since it provides…

Soft Condensed Matter · Physics 2014-11-18 Florian Thüroff , Christoph A. Weber , Erwin Frey

In this work, we generalize M. Kac's original many-particle binary stochastic model to derive a space homogeneous Boltzmann equation that includes a linear combination of higher-order collisional terms. First, we prove an abstract theorem…

Analysis of PDEs · Mathematics 2022-11-09 Esteban Cárdenas , Nataša Pavlović , William Warner

The non-Markoffian transport equations for the systems of cold Bose atoms confined by a external potential both without and with a Bose-Einstein condensate are derived in the framework of nonequilibrium thermal filed theory (Thermo Field…

Quantum Gases · Physics 2010-07-13 Y. Nakamura , T. Sunaga , M. Mine , M. Okumura , Y. Yamanaka

The theory of cosmological perturbations is extended to spacetimes displaying isotropic expansion but anisotropic curvature. The perturbed Einstein equation and Boltzmann equations for massless and massive particles are derived in a general…

General Relativity and Quantum Cosmology · Physics 2014-05-08 T. G. Zlosnik

We start with some global Maxwellian function $M$, which is a stationary solution (with the constant total density $\rho$) of the Boltzmann equation, and we denote the number of the corresponding space variables by $n$. The notion of…

Mathematical Physics · Physics 2011-06-17 Lev Sakhnovich

The departure of a granular gas in the instable region of parameters from the initial homogeneous cooling state is studied. Results from Molecular Dynamics and from Direct Monte Carlo simulation of the Boltzmann equation are compared. It is…

Statistical Mechanics · Physics 2009-11-10 J. Javier Brey , M. J. Ruiz-Montero

A simplified relativistic kinetic theory for gases with internal degrees of freedom, based on a BGK-type collision term, is considered. First the Boltzmann equation is rewritten in tetrad form and then thermal coefficients are determined to…

General Relativity and Quantum Cosmology · Physics 2026-04-13 Philip Semrén , Michael Bradley , João M. S. Oliveira , M. Piedade Machado Ramos

We develop the kinetic theory of classical and quantum particles (fermions and bosons) in gravitational interaction. The kinetic theory of quantum particles may have applications in the context of dark matter. For simplicity, we consider an…

Astrophysics of Galaxies · Physics 2022-08-02 Pierre-Henri Chavanis

Boltzmann equation describes the time development of the velocity distribution in the continuum fluid matter. We formulate the equation using the field theory where the {\it velocity-field} plays the central role. The properties of the…

High Energy Physics - Theory · Physics 2015-11-17 Shoichi Ichinose
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