In these days, the angel of topology and the devil of abstract algebra fight for the soul of every individual discipline of mathematics.
— H. Weyl, Invariants; Duke Math. J., 5 (1939), 489–502.
In these days, the angel of topology and the devil of abstract algebra fight for the soul of every individual discipline of mathematics.
— H. Weyl, Invariants; Duke Math. J., 5 (1939), 489–502.
Organizers: Spencer Dowdall, Dan Margalit, Denis Osin
Time: Wednesdays, 4:10–5:00pm
Location: SC 1432
Mailing List: If you would like to be added to the seminar mailing list and receive regular announcements, please contact one of the organizers.
Fall 2025 - Spring 2026
Wednesday, September 10
Dan Margalit (Vanderbilt)
Title: Algorithms for pseudo-Anosov maps
Abstract: In joint work with Strenner, Taylor, and Yurttas, we give an algorithm whose input is a product of Dehn twists and whose output is the Nielsen-Thurston type of the associated mapping class, along with the associated data: period, reducing curves, stretch factor, and foliations. Our main theorem explains why Mark Bell's program Flipper works. We aim to make the talk accessible to students learning about mapping class groups.
Wednesday, September 17
Denis Osin (Vanderbilt)
Title: Simple p-adic Lie groups with abelian Lie algebras
Abstract: For each prime p and each positive integer d, we construct the first examples of second countable, topologically simple, p-adic Lie groups of dimension d with abelian Lie algebras. This answers a question asked by P.-E. Caprace and N. Monod. In my talk, I will survey the necessary background material and explain why this question is of fundamental importance in the theory of p-adic Lie groups. Perhaps surprisingly, the proof of the main result makes use of small cancellation techniques in groups acting on hyperbolic spaces. Geometric ideas come into play through a general construction that associates a non-discrete, totally disconnected topological group with any discrete group satisfying a certain algebraic condition. The talk is based on joint work with P.-E. Caprace and A. Minasyan.
Wednesday, September 24
TBA
Wednesday, October 1
Nic Brody (UC Santa Cruz)
Title: TBA
Abstract: TBA
Host: Talia Fernos
Wednesday, October 15
TBA
Wednesday, October 22
Thomas Hill (University of Utah)
Title: TBA
Abstract: TBA
Host: Spencer Dowdall
Wednesday, October 29
TBA
Wednesday, November 5
Daniel Groves (University of Illinois, Chicago)
Title: TBA
Abstract: TBA
Host: Talia Fernos
Wednesday, November 12
TBA
Wednesday, November 19
Tina Torkaman (University of Chicago)
Title: TBA
Abstract: TBA
Host: Spencer Dowdall
Wednesday, November 19
TBA
Wednesday, December 3
TBA
Wednesday, January 14
TBA
Wednesday, January 21
TBA
Wednesday, January 28
TBA
Wednesday, February 4
TBA
Wednesday, February 11
TBA
Wednesday, February 18
Anush Tserunyan (McGill University)
Title: TBA
Abstract: TBA
Host: Denis Osin
Wednesday, February 25
TBA
Wednesday, March 4
TBA
Wednesday, March 18
TBA
Wednesday, March 25
TBA
Wednesday, April 1
TBA
Wednesday, April 8
TBA
Wednesday, April 15
TBA