Quantitative propagation of chaos on arbitrary finite time intervals for the three-dimensional repulsive Vlasov-Poisson-Fokker-Planck equation

Abstract

We prove quantitative propagation of chaos in total variation for repulsive Vlasov--Riesz--Fokker--Planck (VRFP) equations on $\mathbb{T}^d$ and $\mathbb{R}^d$ with unregularized interaction potentials with singularity $|x|^{-s}$, $0<s<d/2$. On every finite time interval on which the limiting classical solution satisfies the stated regularity assumptions, the particle marginals with a product initial law converge at an algebraic rate in the particle number, with constants growing at most exponentially in the marginal order. For the three-dimensional repulsive Vlasov--Poisson--Fokker--Planck (VPFP) equation on $\mathbb{R}^3$, a weighted $C^m$ initial probability density, $m\ge3$, with Gaussian velocity decay and polynomial spatial decay of order $M>3$ gives convergence to the global classical solution on every finite time interval. The proof combines conditioning of the initial product law with weighted BBGKY estimates. A decomposition of the potential and a bounded modification of the far-field force yield weighted bounds growing geometrically in the marginal order on the prescribed interval. A centered second-moment estimate permits summation of the error hierarchy, and a synchronous coupling transfers the estimate to the original dynamics.