Geometry Seminar

Winter 2021

- Thursday January 21 at 3:40-4:30pm in Zoom
- Kevin Schreve, University of Chicago
- Invariant random subgroups
- Abstract: This talk is intended to provide some background for Mikolaj Fraczyk's talk next week. I will introduce the Chabauty topology, Benjamini-Schramm convergence, and invariant random subgroups.
- Thursday January 28 at 3:40-4:30pm in Zoom
- Mikolaj Fraczyk, University of Chicago
- Injectivity radius of discrete subgroups of higher rank groups
- Abstract: Let G be a simple higher rank Lie group and let X be the associated symmetric space. Margulis conjectured that any discrete subgroup Gamma of G such that X/Gamma has uniformly bounded injectivity radius must be a lattice. I will present the proof of this conjecture and explain how stationary random subgroups play the central role in the argument. The talk will be based on a recent joint work with Tsachik Gelander.
- Thursday February 4 at 3:40-4:30pm in Zoom
- Kasia Jankiewicz, University of Chicago
- TBA
- Abstract: TBA
- Thursday February 11 at 3:40-4:30pm in Zoom
- Alexander Olshanskiy, Vanderbilt University
- TBA
- Abstract: TBA
- Thursday February 18 at 3:40-4:30pm in Zoom
- Danny Calegari, University of Chicago
- TBA
- Abstract: TBA
- Thursday February 25 at 3:40-4:30pm in Zoom
- Daniil Rudenko, University of Chicago
- TBA
- Abstract: TBA