We give some birationality criteria for m(m = 4,5,6,7) on general type 3-folds with pg 2 by means of an intensive classification. In particular,we show that 7 is not birational if and only if pg(X) = 2and X admits a g...We give some birationality criteria for m(m = 4,5,6,7) on general type 3-folds with pg 2 by means of an intensive classification. In particular,we show that 7 is not birational if and only if pg(X) = 2and X admits a genus 2 curve family of canonical degree23. When the canonical volume is large,we also characterize the birationality of 4,5 and 6.展开更多
基金supported by National Natural Science Foundation of China(GrantNos.11171068,11121101 and 11231003)
文摘We give some birationality criteria for m(m = 4,5,6,7) on general type 3-folds with pg 2 by means of an intensive classification. In particular,we show that 7 is not birational if and only if pg(X) = 2and X admits a genus 2 curve family of canonical degree23. When the canonical volume is large,we also characterize the birationality of 4,5 and 6.
