*主持人：罗栗 副教授
*时间：2020年12月18日9:00-10:00
*地点：腾讯会议 房间号：456 394 627

*讲座内容简介：
The Chern-Schwartz-MacPherson (CSM) class is a Chern class theory for singular varieties. In this talk, we will talk about several results about the CSM classes of the Schubert cells. They are related to the Maulik-Okounkov stable bases for the cotangent bundle of the flag varieties, which coincide with characteristic cycles of certain D-modules on the flag variety. The positivity of the characteristic cycles is used to prove a positivity conjecture of Aluffi and Mihalcea. Moreover, these classes are also used to generalize the classical hook formulas. Based on joint works with Aluffi, Mihalcea, Schürmann, and Naruse.

*主讲人简介：
苏长剑博士，毕业于美国哥伦比亚大学。曾在法国高等科学研究所等机构从事博士后研究工作，现任职于加拿大多伦多大学，主要研究方向为几何表示论。他的工作发表在Ann. Sci. ?c. Norm. Supér.、Adv. Math.、Selecta Math. 等多个国际主流数学杂志上。