On strongly F-regular inversion of adjunction

摘要

In this article we give two independent proofs of the positive characteristic analog of the log terminal inversion of adjunction. We show that for a pair (X, S + B) in characteristic p > 0, if (S-n, B-sn) is strongly F-regular, then S is normal and (X, S + B) is purely F-regular near S. We also answer affirmatively an open question about the equality of F-Different and Different. (C) 2015 Elsevier Inc. All rights reserved.