11:15 – 12:00 College House Ground Floor Study Area  Tea, Coffee and Biscuits 
12:00 – 13:00 PHY LTA  James Griffin (Coventry) Moduli
spaces of labelled graphs
Although Aut(Fr) has a finite simplicial set as a classifying space,
its homology is extremely difficult to calculate and the problem just
gets worse as the rank r increases. However by a result of
Hatcher and Vogtmann the homology is known to be stable, and Galatius
computed this stable homology to be that of the sphere spectrum.
More generally Hatcher and Wahl conjectured that automorphism groups
Aut(H*G*...*G) of free products of groups are homologically stable.
I'll prove this via a moduli space of labelled graphs and a little
category theory.

14:30 – 15:30 BEN LT1 (note room change)  Sarah Whitehouse (Sheffield) (note change of speaker) Binomial rings in topology A
binomial ring is a torsionfree commutative ring that is closed under
the binomial operations r(r1)...(rn+1)/n! for all positive integers
n. They were first introduced by Hall around 1969 and they are related
to integervalued polynomials, Witt vectors and lambdarings. I will
discuss properties of these rings and explain how some
interesting examples arise in topology. (This is a last minute change to the programme.) 
15:30 – 16:00 Bennett Foyer  Tea, Coffee and Biscuits 
16:00 –17:00 BEN LT5  Jeff Giansiracusa (Swansea) Variations on a theme  ribbon graphs, topological conformal field theories and Hochschild homology Costello
used a ribbon graph model of the moduli space of Riemann surfaces to
show that open topological conformal field theories are equivalent to
Ainfinity categories, and that such a theory has a universal extension
to an openclosed theory whose closed state space is the Hochschild
chains on the open part. I will explain how this picture
generalizes to unoriented surfaces, and surfaces equipped with
principle Gbundles, among other structures. In the unoriented
case, this is joint work with Ramses Fernandez Valencia; Mobius graphs
and an involutive variant of Hochschild homology appear. 