Dept Math & Stat UiT, Forskningsparken B459
  23 Nov 2023 Thu 14:15-15:30
  29 Nov 2023 Wed 15:15-16:30

Boris Kruglikov (UiT)

"Some applications of group cohomology"

Let G be a Lie group and M its module. I will discuss various cohomology groups H^k(G,M). Those appear in several seemingly unrelated fields:
(i) The problem of existence of a universal cover for a disconnected Lie group (ex: joint work with Andrea Santi on 3-nondegenerate CR structures).
(ii) The problem of multiplier for relative invariants (ex: joint work with Eivind Schneider on relative differential invariants).
(iii) The problem of global topological anomalies in field theories (ex: from discussions around 1-day workshop "Geometric structures in physics").