A remark on N. Korevaar's concavity maximum principle and on the asymptotic uniqueness of solutions to the plasma problem

Abstract

AbstractRecently N. Korevaar developed a method of proving that solutions to elliptic and parabolic boundary value problems on convex domains ω ⊂ Rn are convex functions. He introduced a concavity functionmagnified imageand used the classical maximum principle to prove that C ⩾ 0 on ω × ω, i.e. that u is convex. Both he and independently L. Caffarelli and J. Spruck applied this method successfully to various boundary value problems. In this note we weaken the assumptions of their theorems and obtain some interesting new applications which are not covered by their previous results [CS, Ko].