Saved in:
Bibliographic Details
Main Author: Pieroni, Francesca
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2504.06839
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911518990270464
author Pieroni, Francesca
author_facet Pieroni, Francesca
contents We consider the kinetic transport equation that arise in the Boltzmann-Grad limit of the two-dimensional periodic Lorentz Gas. This equation has been obtained by extending the phase space of positions and velocities through the introduction of two new variables, representing respectively the time to the next collision and the corresponding impact parameter. Here we mostly focus on the case of periodic boundary conditions on the positions space: we prove that, under suitable hypothesis, the time evolution of a probability density on the extended phase space converges to the equilibrium state with respect to the $L^p$ norm ($^*$-weakly if $p=\infty$), if such initial density is $L^p$. If $p=2$, or if the initial datum does not depend on the position, we also get more precise estimates about the rate of the approach to the equilibrium. Our proof is based on the analysis of the long time behavior of the Fourier coefficients of the solution.
format Preprint
id arxiv_https___arxiv_org_abs_2504_06839
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Convergence to the equilibrium for the kinetic transport equation in the two-dimensional periodic Lorentz Gas
Pieroni, Francesca
Mathematical Physics
Analysis of PDEs
35Q20, 82B40
We consider the kinetic transport equation that arise in the Boltzmann-Grad limit of the two-dimensional periodic Lorentz Gas. This equation has been obtained by extending the phase space of positions and velocities through the introduction of two new variables, representing respectively the time to the next collision and the corresponding impact parameter. Here we mostly focus on the case of periodic boundary conditions on the positions space: we prove that, under suitable hypothesis, the time evolution of a probability density on the extended phase space converges to the equilibrium state with respect to the $L^p$ norm ($^*$-weakly if $p=\infty$), if such initial density is $L^p$. If $p=2$, or if the initial datum does not depend on the position, we also get more precise estimates about the rate of the approach to the equilibrium. Our proof is based on the analysis of the long time behavior of the Fourier coefficients of the solution.
title Convergence to the equilibrium for the kinetic transport equation in the two-dimensional periodic Lorentz Gas
topic Mathematical Physics
Analysis of PDEs
35Q20, 82B40
url https://arxiv.org/abs/2504.06839