The String Coffee Table

Talk at IIASS: Nonabelian Strings

Posted by Urs Schreiber

Next week the Istituto Internazionale per gli alti Studi Scientifici hosts the conference Problemi Attuali di Fisica Teorica in Vietri sul Mare (Italy). As I have mentioned before, I’ll give a talk on ‘nonabelian strings’ concerned with
2-bundles, 2-connections and 2-holonomy and the relation to nonabelian gerbes.

Here are the slides: VietriTalk.ps.

(Special thanks go once again to Eric Forgy for having provided the picture that I display on the title slide.)

Here is the abstract:

Intersections of membranes with stacks of M5-branes are expected to give rise to a dimensional generalization of nonabelian gauge theory from point particles to strings. This can be described in the language of nonabelian gerbes. A gerbe is a generalization of the concept of a sheaf of sections of a fiber bundle obtained by a method known as categorification. Applying the same method to the more direct description of bundles in terms of projection maps and local trivializations yields the concept of a 2-bundle. We describe the theory of 2-bundles in general, how gerbes are obtained from 2-bundles and how global nonabelian surface holonomy can be defined using 2-bundles. This should play a role both for action principles of nonabelian strings as well as for elliptic cohomology.