When:
Thursday, October 30, 2025
1:00 PM - 2:00 PM CT
Where: Swift Hall, 107, 2029 Sheridan Road, Evanston, IL 60208 map it
Audience: Faculty/Staff - Student - Post Docs/Docs - Graduate Students
Contact:
Antonio Auffinger
(847) 491-5524
tuca@northwestern.edu
Group: Department of Mathematics: Special Events
Category: Lectures & Meetings
Title: Group stability and approximation
Abstract: In this talk, we will show how group stability (the question of whether every "almost" representation is a small deformation of a real one) can be considered a non-commutative version of code testability. We then use it to show a number of non-approximation results by using the high-dimensional expanders and the results of Garland and of Deligne. Based on joint works with Glebsky, Thom, Oppenheim, Bachner, and Dogon.