Virtual Seminar on
Geometry and Topology
How to join
Zoom Meeting ID 739-035-2844
Password Zero minus the Euler characteristic of a closed oriented surface of genus 4000
Time Wed 4 pm or Thursday 9 am (or so) in KST (Korea Standard Time)
September 23 (W)
October 14 (W) 5 pm, Korea = 8 am, UK (note the time!), Zoom 739-035-2844
Henry Wilton (Cambridge)
On stable primitivity rank
The commutator length of an element w of the commutator subgroup of a group G is the minimal number of commutators needed to express w as a product of commutators. A more fruitful definition is obtained by stabilising the definition, yielding the notion of *stable* commutator length.
In the context of free groups, Puder has recently introduced the notion of *primitivity rank*, which can be thought of as a homotopical version of commutator length. In this talk, I’ll propose a stable version of primitivity rank, and state some of its properties.
October 28 (W) & more (mini-course). 9 am, Zoom 739-035-2844
Michael Landry (Washington University St. Louis)
November 25 (W) 10 am (note the time!), Zoom 739-035-2844
Kathryn Mann (Cornell)