MATSUSHITA, D: On smooth 4-fold flops

Saitama Mathematical Journal 1997(Vol. 15) pp.17-54

Abstract

A 3-fold flop preserves the analytic structure. Especially, the flop of a smooth 3-fold is smooth. On the contrary, a 4-fold flop does not preserve the analytic structure. In this note, we show by using toric geometry that every isolated Gorenstein terminal cyclic quotient singularity arises on flops of a smooth 4-fold

1991 AMS subject classification

Primary 14J35, Secondary 14E05, 14M25