There is a well-known interpretation of group cohomology in terms of (generalized) group extensions. For a connected semisimple compact Lie group K, we prove that the extensions corresponding to classes in H 4(BK,ℤ) can be interpreted in terms of automorphisms of a pair consisting of a type II1 von Neumann algebra and a Cartan subalgebra.
|Original language||English (US)|
|Number of pages||15|
|Journal||Journal of Lie Theory|
|State||Published - 2004|
ASJC Scopus subject areas
- Algebra and Number Theory