April 27th, 2021 | Colloquium
Infinite volume and infinite injectivity radius
We prove the following conjecture of Margulis. Let M=Λ\G/K be a locally symmetric space where G is a simple Lie group of real rank at least 2. If M has infinite volume then it admits injected contractible balls of any radius. This generalizes the celebrated normal subgroup theorem of Margulis to the context of arbitrary discrete subgroups of G and has various other applications. We prove this result by studying random walks on the space of discrete subgroups of G and analysing the possible stationary limits. This is a joint work with Mikolaj Fraczyk.
14:00 - Pretalk with Tsachik Gelander and PhD Students
14:30 - Coffee Break
15:00 - RTG colloquium