SMS scnews item created by Anthony Henderson at Mon 8 Oct 2007 1229
Type: Seminar
Distribution: World
Expiry: 12 Oct 2007
Calendar1: 12 Oct 2007 1205-1255
CalLoc1: Carslaw 373
CalTitle1: Algebra Seminar: Lehrer -- The flag variety and twisted invariants of reflection groups
Auth: anthonyh@asti.maths.usyd.edu.au

Algebra Seminar

The flag variety and twisted invariants of reflection groups

Gus Lehrer

12th October, 12:05-12:55pm, Carslaw 373


Abstract

Let W be the Weyl group of a simple complex Lie group G. If T is a maximal torus of G then W has a graded representation on the cohomology of the flag variety G/T, which is well-known to be equivalent to the representation of W on its coinvariant algebra SW. It has long been known that for certain integers d, the sums of homogeneous components of SW of degrees congruent to k mod d for a fixed k may be expressed as induced representations of W. I shall generalise and explain this in terms of the "twisted invariant theory" of an arbitrary unitary reflection group.