Congruence subgroups and homological stability

Geometry Topology Seminar
Monday, October 10, 2011 - 14:05
1 hour (actually 50 minutes)
Skiles 005
Rice U
An important structural feature of the kth homology group of SL_n(Z) is that it is independent of n once n is sufficiently large.  This property is called "homological stability" for SL_n(Z).  Congruence subgroups of SL_n(Z) do not satisfy homological stability; however, I will discuss a theorem that says that they do satisfy a certain equivariant version of homological stability.