题目：Introduction to Differentiable Stacks and S^1-Gerbes

报告人： 徐平 教授

     （宾州州立大学，State College,美国）

Abstract : Recently, there has been an increasing interest in S^1-gerbes due to their close connections with string theory. In a certain sense, gerbes are geometrical objects describing (equivalence classes) of degree 3 integer cohomology groups. In this mini-course, I will give an elementary introduction to the theory of S^1-gerbes over a differentiable stack using the theory of Lie groupoids. The groupoid interpretation of S^1-gerbes lead naturally to the construction of ``noncommutative spaces", on which the machinery of noncommutative geometry can be applied. As an example,  I will discuss its application to twisted K-theory. Differential stacks, roughly speaking, are Morita equivalence classes of Lie groupoids.  The notion of groupoid is a common generalization of the concepts of space and group. In the theory of groupoids, spaces and groups are treated on equal footing. One could say that a groupoid is a mixture of a space and a group; it has space-like and group-like properties that interact in a delicate way. The theory of Lie groupoids provides an important approach to the problem of endowing an abstract groupoid with a geometric structure, which plays a fundamental role in noncommutative geometry and quantization theory.

时间： 2019年7月1日、7月3日、

7月5日、7月8日、7月10日、7月12日

上午9:30-11:30

地点：565net必赢客户端本部教二楼612教室

联系人：杨紫峰

欢迎全体师生积极参加！