Speaker:Stavros Papadakis (Lisbon)

Title: Equivariant degenerations of spherical modules

Abstract: Assume G is a complex reductive affine algebraic group, and let h : \Lambda^+ to {0,1} be a function, where \Lambda^+ denotes the set of isomorphism classes of finite dimensional irreducible G-modules. We denote by Q_h the direct sum of the elements V of \Lambda^+ with h(V) =1. Alexeev and Brion have defined a moduli scheme M^G_h which, in a certain sense, parametrizes the affine G-schemes X such that the (rational) G-modules \CC[X] and Q_h are isomorphic. The talk will be about joint work with Bart Van Steirteghem (New York) which studies the nonsingularity of M^G_h under the additional assumptions that the group G is of type A and there exists a finite dimensional G-module W with \CC[W] isomorphic to Q_h.