English

Reductive groups, the loop Grassmannian, and the Springer resolution

Representation Theory 2018-04-13 v3

Abstract

In this paper we prove equivalences of categories relating the derived category of a block of the category of representations of a connected reductive algebraic group over an algebraically closed field of characteristic pp bigger than the Coxeter number and a derived category of equivariant coherent sheaves on the Springer resolution (or a parabolic counterpart). In the case of the principal block, combined with previous results, this provides a modular version of celebrated constructions due to Arkhipov-Bezrukavnikov-Ginzburg for Lusztig's quantum groups at a root of unity. As an application, we prove a "graded version" of a conjecture of Finkelberg-Mirkovi\'c describing the principal block in terms of mixed perverse sheaves on the dual affine Grassmannian.

Keywords

Cite

@article{arxiv.1602.04412,
  title  = {Reductive groups, the loop Grassmannian, and the Springer resolution},
  author = {Pramod N. Achar and Simon Riche},
  journal= {arXiv preprint arXiv:1602.04412},
  year   = {2018}
}

Comments

112 pages. v3: minor corrections

R2 v1 2026-06-22T12:49:49.739Z