Algebra Seminar: Robertson -- Framed Little Discs and The Grothendieck-Teichmuller Group

Marcy Robertson (University of Melbourne) 

Friday 18 November, 12-1pm, Place: Carslaw 375 

Framed Little Discs and The Grothendieck-Teichmuller Group 

In this talk we describe how ribbon braid groups can be used to provide groupoid models
for the framed little 2 disks operad.  We will then show how one uses these groupiod
models to show that (homotopy) automorphisms of framed little disks is equivalent to a
model of the Grothendieck-Teichmuller group.  This talk will not assume familiarity
with operads or Grothendieck-Teichmuller theory.  All work is joint with Geoffroy
Horel and Pedro Boavida.