November 5 : Andrei Neguț

Title: (parabolic) W-algebras and moduli of (parabolic) sheaves

Abstract:

There is a general picture that physicists call AGT, but geometers would interpret as the connection between the cohomology/K-theory of the moduli space of rank r sheaves on a surface and q-W-algebras for gl_r. I'll present a survey of this connection, plus a tentative generalization to moduli space of parabolic (i.e. endowed with a flag structure on a divisor) sheaves. The algebraic object is expected to match the, yet undefined, q-W-algebra associated to gl_r and arbitrary nilpotent element.