English

The parabolic exotic t-structure

Representation Theory 2018-11-21 v2

Abstract

Let G be a connected reductive algebraic group over an algebraically closed field k, with simply connected derived subgroup. The exotic t-structure on the cotangent bundle of its flag variety T^*(G/B), originally introduced by Bezrukavnikov, has been a key tool for a number of major results in geometric representation theory, including the proof of the graded Finkelberg-Mirkovic conjecture. In this paper, we study (under mild technical assumptions) an analogous t-structure on the cotangent bundle of a partial flag variety T^*(G/P). As an application, we prove a parabolic analogue of the Arkhipov-Bezrukavnikov-Ginzburg equivalence. When the characteristic of k is larger than the Coxeter number, we deduce an analogue of the graded Finkelberg-Mirkovic conjecture for some singular blocks.

Keywords

Cite

@article{arxiv.1805.05624,
  title  = {The parabolic exotic t-structure},
  author = {Pramod Achar and Nicholas Cooney and Simon Riche},
  journal= {arXiv preprint arXiv:1805.05624},
  year   = {2018}
}
R2 v1 2026-06-23T01:55:24.957Z