Poincaré duality in equivariant intersection theory
Amphitéâtre Léon Motchane (IHES)
Amphitéâtre Léon Motchane
Le Bois Marie
35, route de Chartres
The aim of this talk is to provide a notion of Poincaré duality for the Chow groups of singular varieties where a torus acts with finitely many fixed points. We relate this concept to the usual notion of Poincaré duality in the smooth and rationally smooth cases (e.g. Betti numbers). Finally, we characterize it in terms of equivariant multiplicities, i.e. certain rational functions having poles along hyperplanes associated to the weights of the action.