Institut for Matematiske Fag > Kalender

Institut for Matematiske Fags kalender

Algebra-/topologiseminar
Reduced fusion systems over 2-groups of sectional rank at most four
Taler(e): Bob Oliver
(Université PARIS 13)
Mandag den 16. juli 2012 kl. 15:15-16:15. Sted: Aud 8. Sprog: engelsk.

The sectional rank of a $p$-group is the largest rank of any of its abelian subquotients. One of the steps towards classifying finite simple groups was the 1974 book by Gorenstein and Harada, where they list all finite simple groups whose Sylow 2-subgroup has sectional rank at most four.

I want to describe a similar result, listing all reduced fusion systems over 2-groups of sectional rank at most four. The list contains no surprises: it consists entirely of fusion systems of simple groups on the Gorenstein-Harada list. But the method of proof seems very different, since it is based on studying the different types of essential subgroups which can occur, rather than the centralizers of involutions. This also leads to a different way of organizing the final result, which I hope will be of interest.

Organiseret af Ellen Henke