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Related papers: A gradient flow approach to the Boltzmann equation

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We present a new direct simulation Monte-Carlo method for solving the relativistic Boltzmann equation. We solve numerically the 2-dimensional Boltzmann equation using this new algorithm. We find that elliptic flow from this transport…

Nuclear Theory · Physics 2008-11-26 Clement Gombeaud , Jean-Yves Ollitrault

I present a solution to the full Einstein-fluid equations representing a self-gravitating Bjorken flow. The motion and the geometry become inhomogeneous in the plane transversal to the flow and the energy density profile acquires, due to…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Alexander Feinstein

We consider a Fokker-Planck equation which is coupled to an externally given time-dependent constraint on its first moment. This constraint introduces a Lagrange-multiplier which renders the equation nonlocal and nonlinear. In this paper we…

Analysis of PDEs · Mathematics 2018-11-28 Simon Eberle , Barbara Niethammer , André Schlichting

Flows are exact-likelihood generative neural networks that transform samples from a simple prior distribution to the samples of the probability distribution of interest. Boltzmann Generators (BG) combine flows and statistical mechanics to…

Machine Learning · Statistics 2019-10-03 Jonas Köhler , Leon Klein , Frank Noé

The traffic modelling often keeps the mesoscopic scale in the theoretical sphere because the integro-differential nature of its equations. In the present work we suggest to use the lattice Boltzmann method to overcome these difficulties. In…

Physics and Society · Physics 2018-10-01 Romain Noël , Laurent Navarro , Guy Courbebaisse

This manuscript focus on an extensive survey with new techniques on the problem of solving the Boltzmann flow by bringing a unified approach to the Cauchy problem to homogeneous kinetic equations with Boltzmann-like collision operators…

Mathematical Physics · Physics 2023-01-11 Ricardo J. Alonso , Irene M. Gamba

We analyze the gradient flow of a potential energy in the space of probability measures when we substitute the optimal transport geometry with a geometry based on Sinkhorn divergences, a debiased version of entropic optimal transport. This…

Analysis of PDEs · Mathematics 2025-11-19 Mathis Hardion , Hugo Lavenant

In this paper we present a stochastic homogenization result for a class of Hilbert space evolutionary gradient systems driven by a quadratic dissipation potential and a $\Lambda$-convex energy functional featuring random and rapidly…

Analysis of PDEs · Mathematics 2019-05-08 Martin Heida , Stefan Neukamm , Mario Varga

We introduce the consecutive lifting-projection (LP) flow as a novel approximation framework for the spatially homogeneous Boltzmann and Landau equations. The key idea is to lift the nonlinear collision operator to a higher dimensional…

Numerical Analysis · Mathematics 2026-05-06 Kun Huang

The method of choice for integrating the time-dependent Fokker-Planck equation in high-dimension is to generate samples from the solution via integration of the associated stochastic differential equation. Here, we study an alternative…

Machine Learning · Computer Science 2023-02-17 Nicholas M. Boffi , Eric Vanden-Eijnden

In this paper we give a description of the asymptotic behavior, as $\epsilon\to 0$, of the $\epsilon$-gradient flow in the finite dimensional case. Under very general assumptions we prove that it converges to an evolution obtained by…

Functional Analysis · Mathematics 2007-05-23 Chiara Zanini

We propose a general method to identify nonlinear Fokker--Planck--Kolmogorov equations (FPK equations) as gradient flows on the space of probability measures on $\mathbb{R}^d$ with a natural differential geometry. Our notion of gradient…

Analysis of PDEs · Mathematics 2024-11-11 Marco Rehmeier , Michael Röckner

The observation of fluid-like behavior in nucleus-nucleus, proton-nucleus and high-multiplicity proton-proton collisions motivates systematic studies of how different measurements approach their fluid-dynamic limit. We have developed…

High Energy Physics - Phenomenology · Physics 2020-11-11 Aleksi Kurkela , Seyed Farid Taghavi , Urs Achim Wiedemann , Bin Wu

A type of discrete Boltzmann model for simulating shallow water flows is derived by using the Hermite expansion approach. Through analytical analysis, we study the impact of truncating distribution function and discretizing particle…

Fluid Dynamics · Physics 2018-07-16 Jianping Meng , Xiao-Jun Gu , David R Emerson , Yong Peng , Jianmin Zhang

We analyze the dynamics of concentrated polymer solutions modeled by a 2D Smoluchowski equation. We describe the long time behavior of the polymer suspensions in a fluid. When the flow influence is neglected the equation has a gradient…

Analysis of PDEs · Mathematics 2025-09-17 Xingyu Li , Arghir Zarnescu

A detailed analysis is presented to demonstrate the capabilities of the lattice Boltzmann method. Thorough comparisons with other numerical solutions for the two-dimensional, driven cavity flow show that the lattice Boltzmann method gives…

comp-gas · Physics 2009-10-22 Shuling Hou , Qisu Zou , Shiyi Chen , Gary D. Doolen , Allen C. Cogley

The Ricci flow is a parabolic evolution equation in the space of Riemannian metrics of a smooth manifold. To some extent, Einstein equations give rise to a similar hyperbolic evolution. The present text is an introductory exposition to…

Differential Geometry · Mathematics 2011-06-27 Abdelghani Zeghib

Gaseous flows show a diverse set of behaviors on different characteristic scales. Given the coarse-grained modeling in theories of fluids, considerable uncertainties may exist between the flow-field solutions and the real physics. To study…

Computational Physics · Physics 2021-05-05 Tianbai Xiao , Martin Frank

We consider a stochastic $N$-particle model for the spatially homogeneous Boltzmann evolution and prove its convergence to the associated Boltzmann equation when $N\to \infty$. For any time $T>0$ we bound the distance between the empirical…

Probability · Mathematics 2015-05-13 Remi Peyre

We use the distances introduced in a previous joint paper to exhibit the gradient flow structure of some drift-diffusion equations for a wide class of entropy functionals. Functional inequalities obtained by the comparison of the entropy…

Analysis of PDEs · Mathematics 2012-12-06 Jean Dolbeault , Bruno Nazaret , Giuseppe Savaré