Seminar on Discrete Mathematics: Permutation module decomposition of the cohomology of a regular semisimple Hessenberg variety

Speaker：Soojin Cho (AJOU University)

Time：2026-5-27 14:00

Location：Zoom Meeting ID: 714-1526-6102 (Password: 260527) & Room S105

Abstract:

We consider the module structure of the cohomology of regular semisimple Hessenberg varieties (of type A) under the symmetric group action. We use BB(Bialynicki-Birula) basis of the cohomology space to construct permutation module decomposition of the cohomology for the Hessenberg varieties associated with lollipop graphs and the second degree cohomology for general cases. This talk is based on the works done with Jaehyun Hong and Eunjeong Lee, and with JiSun Huh and Seonjeong Park.