This talk is taking place at UC 152 instead of the usual room of BA6183.
For a compact symplectic manifold with a Hamiltonian unitary group action, Atiyah-Bott and Kirwan showed that the equivariant cohomology with the rational coefficient is formal, a cohomological condition as if the action is trivial in a suitable sense. In this talk, I will discuss how to generalize this result to integral cohomology, or more generally, any complex-oriented cohomology theory. This is joint work with Daniel Pomerleano.