VELOCITY AVERAGING AND HÖLDER REGULARITY FOR KINETIC FOKKER--PLANCK EQUATIONS WITH GENERAL TRANSPORT OPERATORS AND ROUGH COEFFICIENTS.

This article addresses the local boundedness and Hölder continuity of weak solutions to kinetic Fokker--Planck equations with general transport operators and rough coefficients. These results are due to the mixing effect of diffusion and transport. Although the equation is parabolic only in the velocity variable, it has a hypoelliptic structure provided that the transport part ∂ t + b(v). ∇x is nondegenerate in some sense. We achieve the results by revisiting the method, proposed by Golse, Imbert, Mouhot, and Vasseur in the case b(v) = v, that combines the elliptic De Giorgi--Nash--Moser theory with velocity averaging lemmas. [ABSTRACT FROM AUTHOR]