Seminar der Forschergruppe 'Symmetrie, Geometrie und Arithmetik'

Throughout the 20th century, the "accidental" equalities of Dynkin diagrams of small rank have been exploited in various ways to describe torsors for the corresponding linear algebraic groups over fields and rings. In this talk, we will present these descriptions in the context of torsors over algebraic varieties. In the case of A_3=D_3, we will show how this description can be used to give a "hermitian K-theoretic" obstruction to the existence of global points of projective three-space bundles over four folds. In particular, this obstruction detects line subbundles of rank four vector bundles.

Freitag, den 3. Dezember 2010 um 16:15 Uhr, in INF 288, HS 3 Freitag, den 3. Dezember 2010 at 16:15, in INF 288, HS 3