题目：On the characteristic cycle of a constructible sheaf on a surface (II)

报告人：胡昊宇（南开大学与巴黎十一大）

时间：3月30日，4月1日下午2：30-4：30

地点：晨兴610

摘要： In these two talks, we continue the discussion on T. Saito’s recent work on characteristic cycles for l-adic sheaves. In this work, he constructed the characteristic cycle of a constructible sheaf on a surface in the cotangent bundle using Radon transform and the ramification theory. To give a Milnor type formula that expresses the total dimension of the nearby cycle of the sheaf as the intersection of the characteristic cycle and a section, a deformation method is  needed. In this lecture,  we briefly recall the Radon transform and the construction of characteristic cycles, and then, we focus on the usage of the deformation method.