报告题目 (Title)：Relative expander graphs, metric embeddings into Banach spaces and higher index problems（相对展开图、Banach空间中的度量嵌入和高指标问题）

报告人 (Speaker)：王勤 教授（华东师范大学）

报告时间 (Time)：2024年4月24日(周三) 10:00

报告地点 (Place)：校本部GJ303

邀请人(Inviter)：席东盟、李晋、张德凯、吴加勇

主办部门：理学院数学系

报告摘要：Relative expanders are families of Cayley graphs whose metric geometry lies in between the geometry of a Hilbert space and that of a genuine expander. They were introduced by Arzhantseva and Tessera in terms of relative Poincare inequalities. In fact, these spaces do not coarsely embed into any uniformly curved Banach space introduced by Pisier. We show that certain relative expanders satisfy the coarse Baum-Connes conjecture and possesses operator K-theory amenability. In this lecture, we will discuss some of key ideas and results in this circle of developments.