Speaker
Prof.
Florian Naef
(Dublin)
Description
By a deep result of Hain, we know generators and relations of the (relative) Malcev completion of mapping class groups. In the limit where the genus goes to infinity, there is a description of that Lie algebra as the cohomology of a certain graph complex (closely related to higher genus Grothendieck-Teichmüller Lie algebras). By computing the cohomology of the Koszul dual graph complex, one can deduce stable Koszulness of Hain's Lie algebras.
This is joint work with M. Felder and T. Willwacher.
