20 may 2015 -- 14:30
Aula di Consiglio, Dip. Matematica, Università "La Sapienza", Roma
I will discuss a functorial construction of extensions of mapping class groups of smooth manifolds which are induced by extensions of (higher) diffeomorphisms groups via the group stack of automorphisms of manifolds equipped with higher degree topological structures. The problem of constructing such extensions arises naturally in the study of topological quantum field theories, in particular in 3d Chern-Simons theory. Joint work with Domenico Fiorenza and Urs Schreiber.