# University of Toronto's Symplectic Geometry Seminar

Feb. 2, 2004, 2:10 - 3 PM
SS5017A

## Yi Lin

### Cornell University

Equivariant symplectic Hodge theory and the $d\delta$-lemma

Abstract: Consider a Hamiltonian action of a compact Lie group on a symplectic manifold which has strong Lefschetz property. In this talk I will discuss an equivariant version of the Mekulove-Guillemin $d \delta$-lemma and an improved version of the Kirwan-Ginzburg equivariant formality theorem, which says that every cohomology class has a canonical equivariant extension. This is a joint work with Reyer Sjamaar.