2026/07/27 by Quoc-Hung Nguyen
#math.AP
We prove a local well-posedness criterion for the Vlasov--Poisson system on \Rdx×\Rdv, d≥2, under an anisotropic assumption on the initial distribution. The datum has finite mass, its weighted velocity supremum belongs to Lpx for some p>d, and it has an arbitrarily small positive Hölder regularity in the velocity variable, uniformly with respect to velocity and with the same spatial Lp control. The main estimate is a nonlinear mixing bound [ρ(t)]Cαx\lesssim t-d/p-εC(f0), ε>0~~small. Thus the density is integrable in time with values in a positive spatial Hölder class, and the corresponding electric field belongs to L1tC1,αx. We construct a solution by a Schauder fixed point on the density and prove uniqueness by a Loeper-type stability estimate.