What is a Coxeter group, and why is a Coxeter group?

Series
Algebra Student Seminar
Time
Friday, October 14, 2022 - 10:00am for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
Tong Jin – Georgia Institute of Technology – tongjin@gatech.edu
Organizer
Kevin Shu

A Coxeter group is a (not necessarily finite) group given by certain types of generators and relations. Examples of finite Coxeter groups include dihedral groups, symmetric groups, and reflection groups. They play an important role in various areas. In this talk, I will discuss why I am interested in Coxeter groups from a combinatorial perspective - the geometric concepts associated with the finite Coxeter groups form the language of Coxeter matroids, which are generalizations of ordinary matroids. In particular, finite Coxeter groups are related to Coxeter matroids in the same way as symmetric groups are related to ordinary matroids. The main reference for this talk is Chapter 5 of Borovik-Gelfand-White's book Coxeter Matroids. I will only assume basic group theory, but not familiarity with matroids.