Symmetric functions, parabolic category O and the Springer fiber
arXiv:math/0608235
Abstract
We prove that the center of a regular block of parabolic category O for the general linear Lie algebra is isomorphic to the cohomology algebra of a corresponding Springer fiber. This was conjectured by Khovanov. We also find presentations for the centers of singular blocks, which are cohomology algebras of Spaltenstein varieties.
33 pages