Topology and Group Theory Seminar
Topology and Group Theory Seminar: April 16, 2025
Mar. 9, 2025—Speaker: Robbie Lyman (Rutgers) Title: Graphical models for groups Abstract: In geometric group theory, we love groups and graphs. Every (abstract) group has (many) Cayley graphs, each one associated with a choice of a generating set. Recently I’ve been curious about topological groups, inspired by the budding theory around and community of people inspired by mapping class...
Topology and Group Theory Seminar: April 9, 2025
Mar. 9, 2025—Speaker: John Ratcliffe (Vanderbilt) Title: The G-index of a spin closed hyperbolic 4-manifold M Abstract: In this talk, we will show how to compute the G-index of a spin closed hyperbolic 4-manifold M for a group G of symmetries of a spin structure on M. As an example, we will compute the G-index for the group G of symmetries of the fully symmetric spin structure on...
Topology and Group Theory Seminar: April 2, 2025
Mar. 8, 2025—Speaker: Talia Fernos (Vanderbilt) Title: Lattice envelopes and groups acting AU-acylindrically on products of hyperbolic spaces Abstract: In this joint work with Balasubramanya, we explore the capacity for a group acting AU-acylindrically on a finite product of delta-hyperbolic spaces to satisfy three properties introduced by Bader, Furman, and Sauer. When satisfied, these properties restrict the potential ambient group...
Topology and Group Theory Seminar: March 26, 2025
Mar. 7, 2025—Speaker: Caglar Uyanik (University of Wisconsin, Madison) Title: TBA Abstract: TBA Host: Spencer Dowdall
Topology and Group Theory Seminar: March 19, 2025
Mar. 6, 2025—Speaker: Oishee Banerjee (Florida State University) Title: TBA Abstract: TBA Host: Dan Margalit
Topology and Group Theory Seminar: March 5, 2025
Mar. 5, 2025—Speaker: Madeline Brandt (Vanderbilt) Title: TBA Abstract: TBA
Topology and Group Theory Seminar: February 26, 2025
Feb. 26, 2025—Speaker: Matt Zaremsky (SUNY Albany) Title: Aut(Fn) satisfies the Boone-Higman conjecture Abstract: The Boone-Higman conjecture (1973) predicts that a finitely generated group has solvable word problem if and only if it embeds in a finitely presented simple group. The “if” direction is true and easy, but the “only if” direction has been open for over 50...
Topology and Group Theory Seminar: February 19, 2025
Feb. 19, 2025—Speaker: 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...
Topology and Group Theory Seminar: February 12, 2025
Feb. 12, 2025—Speaker: Jesse Peterson (Vanderbilt) Title: Property HaHaHaHaHaHaHaHaHaHaHa… HaHaHaHaHaHaHaHaHa… HaHaHaHaHaHa… HaHaHa… Abstract: A seminal result of Haagerup from 1979 is that the word length function with respect to a free generating set on a free group is conditionally negative definite. Groups possessing a proper conditionally negative definite function have since been said to have the Haagerup property and...
Topology and Group Theory Seminar: February 5, 2025
Feb. 5, 2025—Speaker: Itamar Vigdorovich (UCSD) Title: Effective mixed identity freeness for higher rank lattices and applications to C*-algebras Abstract: An identity on a group G is a word w that holds throughout the entire group. If w is allowed to include coefficients from G (not just variables), it is called a mixed identity. We show that a lattice Γ in PSL(n, R) has no non-trivial mixed identities in a quantitative and uniform...