Balazs Komuves: Gysin formulae on partial flag bundles

abstract: I would like to show a simple geometric proof of some classical formulae computing the Gysin (or pushforward) map for the projection of a Grassmann bundle (more generally, a partial flag bundle) to its base. The formulae involve Schur polynomials, and the proof uses equivariant localisation to establish the connection between the geometric construction and the combinatorial nature of the result.