摘要
Let(X, ?) be a log pair over S, such that-(KX+ ?) is nef over S. It is conjectured that the intersection of the non-klt(non Kawamata log terminal) locus of(X, ?) with any fiber Xs has at most two connected components. We prove this conjecture in dimension no greater than 4 and in arbitrary dimension assuming the termination of klt flips.
Let(X, ?) be a log pair over S, such that-(KX+ ?) is nef over S. It is conjectured that the intersection of the non-klt(non Kawamata log terminal) locus of(X, ?) with any fiber Xs has at most two connected components. We prove this conjecture in dimension no greater than 4 and in arbitrary dimension assuming the termination of klt flips.
基金
supported by National Science Foundation of USA (Grant Nos. DMS-1300750 and DMS-1265285)
by a grant from the Simons Foundation (Grant No. 256202)