English

On tensor categories attached to cells in affine Weyl groups

Representation Theory 2012-01-04 v2 Category Theory

Abstract

We prove a conjecture by Lusztig, which describes the tensor categories of perverse sheaves on affine flag manifolds, with tensor structure provided by truncated convolution, in terms of the Langlands dual group. We also give a geometric (categorical) description of Lusztig's bijection between two-sided cells in an affine Weyl group, and unipotent conjugacy classes in the Langlands dual group. The main tool is the sheaf-theoretic construction of the center of the affine Hecke algebra due to Gaitsgory (based on ideas of Beilinson and Kottwitz), see math.AG/9912074.

Keywords

Cite

@article{arxiv.math/0010089,
  title  = {On tensor categories attached to cells in affine Weyl groups},
  author = {Roman Bezrukavnikov},
  journal= {arXiv preprint arXiv:math/0010089},
  year   = {2012}
}

Comments

The published version of this paper misquoted a result of Lusztig, this version corrects this mistake (thanks to Xinwen Zhu for pointing it out)

R2 v1 2026-07-22T16:35:06.333Z