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arXiv · 2505.13038

On the mean-field limit of Vlasov-Poisson-Fokker-Planck equations

Li Chen·Jinwook Jung·Peter Pickl·Zhenfu Wang
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Abstract

The derivation of effective descriptions for interacting many-body systems is an important branch of applied mathematics. We prove a propagation of chaos result for a system of $N$ particles subject to Newtonian time evolution with or without additional white noise influencing the velocities of the particles. We assume that the particles interact according to a regularized Coulomb-interaction with a regularization parameter that vanishes in the $N\to\infty$ limit. The respective effective description is the so called Vlasov-Poisson-Fokker-Planck (VPFP), respectively the Vlasov-Poisson (VP) equation in the case of no or sub-dominant white noise. To obtain our result we combine the relative entropy method from \cite{jabinWang2016} with the control on the difference between the trajectories of the true and the effective description provided in \cite{HLP20} for the VPFP case respectively in \cite{LP} for the VP case. This allows us to prove strong convergence of the marginals, i.e. convergence in $L^1$.

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Li Chen, Jinwook Jung, Peter Pickl, Zhenfu Wang. 2025-05-19. On the mean-field limit of Vlasov-Poisson-Fokker-Planck equations. https://arxiv.org/abs/2505.13038

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