Lecturer: Wang Qin

Abstract:

Expander graphs are highly connected and sparse graphs, which do not coarsely embed into Hilbert space, and are sources for counterexamples to the coarse Baum-Connes conjecture. Recently, G. Arzhantseva and R. Tessera introduce a notion of relative expander to give the first example of sequences of finite Cayley graphs of uniformly bounded degree, and even an example of finitely generated group, which do not coarsely embed into any Lp-spaces for any p>1, yet do not contain any genuine expander. We show that the coarse Baum-Connes conjecture holds for all these relative expander graphs and finitely generated groups. This is joint work with Jintao Deng (University of Waterloo) and Guoliang Yu (TAMU).

Introduction to the Lecturer:

Wang Qin, professor and doctoral supervisor of Operator Algebra Research Center, School of Mathematical Sciences, East China Normal University, is mainly engaged in the research of operator algebra, coarse geometry and non-commutative geometry. He has made some important achievements in the important problems of non-commutative geometry, such as "coarse Baum Connes conjecture" and "coarse Novikov conjecture". He was selected into the New Century Talents Support Program of the Ministry of Education of the People's Republic of China, Shanghai Shuguang Talent and Shanghai Pujiang Scholar.

Invitee:

Wang Penghui, Professor from School of Mathematics

Time:

10:00-11:00, December 3 (Friday)

Venue:

Tencent Meeting ID: 564-683-026

Hosted by the School of Mathematics, Shandong University