主讲人：田一超教授(普林斯顿大学)

时  间：1月1日（周六）16：20-17：20

地  点：数学科学学院210教室

备注： Abstract: In this talk, I will first recall the definition of Abbes-Saito filtration of finite flat groups, which is an analogue of the upper ramification filtration of the Galois group of a local field. Then I will give an upper bound of this filtration in terms of the module of invariant differential modules. If time permits, I will discuss its application to theory of canonical subgroups and other related open problems.