BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20260413T063930EDT-6045b5vEBw@132.216.98.100 DTSTAMP:20260413T103930Z DESCRIPTION:Title: Classifying principal bundles for smooth 2-groups\n\nAbs tract: A 2-group is a categorified version of a group: a category with a m ultiplication operator\, for which all group axioms hold up to natural iso morphism. Similarly\, there is a notion of a smooth 2-group\, and of princ ipal 2-group bundles. We classify 2-group bundles in terms of Čech data or transition functions\, which enables us to give a concrete description of the moduli space of principal 2-group bundles.\n\nIn the case of a finite 2-group\, we prove that this moduli space gives a 2-fibration over the mo duli space of flat principal bundles for an ordinary finite group\, and pr ovides a categorification of the Freed–Quinn line bundle\, a mapping-class -group-equivariant line bundle arising in Dijkgraaf–Witten theory for the finite group. We expect analogous results to hold in the smooth setting\, with applications to the Chern-Simons theory of a Lie group. This is joint work with Daniel Berwick-Evans and Laura Murray.\n\nLocation: UQAM PK-567 5\n DTSTART:20260408T180000Z DTEND:20260408T190000Z SUMMARY:Emily Cliff (Université de Sherbrooke) URL:/mathstat/channels/event/emily-cliff-universite-de -sherbrooke-372284 END:VEVENT END:VCALENDAR