Special Session 22: 

Boundary H\{o}lder Regularity for Elliptic Equations

Kai Zhang
Northwestern Polytechnical University
Peoples Rep of China
Co-Author(s):    Guanghao Hong, Dongsheng Li
Abstract:
This talk investigates the relation between the boundary geometric properties and the boundary regularity of the solutions of elliptic equations. We prove by a new unified method the pointwise boundary H\{o}lder regularity under proper geometric conditions. Unified`` means that our method is applicable for the Laplace equation, linear elliptic equations in divergence and non-divergence form, fully nonlinear elliptic equations, the p-Laplace equations and the fractional Laplace equations etc. In addition, these geometric conditions are quite general. In particular, for local equations, the measure of the complement of the domain near the boundary point concerned could be zero. The key observation in the method is that the strong maximum principle implies a decay for the solution, then a scaling argument leads to the H\{o}lder regularity.