A module isomorphism between $H^*_T(G/P)\otimes H^*_T(P/B)$ and $H^*_T(G/B)$
Algebraic Topology
2015-09-03 v2
Abstract
We give an explicit (new) morphism of modules between and and prove (the known result) that the two modules are isomorphic. Our map identifies submodules of the cohomology of the flag variety that are isomorphic to each of and . With this identification, the map is simply the product within the ring . We use this map in two ways. First we describe module bases for that are different from traditional Schubert classes and from each other. Second we analyze a -representation on via restriction to subgroups . In particular we show that the character of the Springer representation on is a multiple of the restricted representation of on .
Keywords
Cite
@article{arxiv.1409.0834,
title = {A module isomorphism between $H^*_T(G/P)\otimes H^*_T(P/B)$ and $H^*_T(G/B)$},
author = {Elizabeth Drellich and Julianna Tymoczko},
journal= {arXiv preprint arXiv:1409.0834},
year = {2015}
}