Canonical forms for free group automorphisms

Seminar: 
Geometry & Topology
Event time: 
Tuesday, November 8, 2022 - 4:15pm
Location: 
LOM 214
Speaker: 
Jean Pierre Mutanguha
Speaker affiliation: 
Institute for Advanced Study
Event description: 

The Nielsen–Thurston theory of surface homeomorphisms can be thought of as a surface analogue to the Jordan Canonical Form. I will discuss my progress in developing a similar canonical form for free group automorphisms. (Un)Fortunately, free group automorphisms can have arbitrarily complicated behaviour. This is a significant barrier to translating arguments that worked for surfaces into the free group setting; nevertheless, the overall ideas/strategies do translate!