English

Generalised Springer correspondence for Z/m-graded Lie algebras

Representation Theory 2022-03-14 v4

Abstract

Let GG be a simple simply connected complex algebraic group and let g\mathfrak{g}_* be a Z/m\mathbf{Z}/m-grading on its Lie algebra g\mathfrak{g}. In a recent series of articles, G. Lusztig and Z. Yun, studied the classification of simple G0G_0-equivariant perverse sheaves on the nilpotent cone of gi\mathfrak{g}_i for iZ/mi\in \mathbf{Z}/m, where G0G_0 is the exponentiation of the degree zero piece g0\mathfrak{g}_0. They proved a decomposition of the equivariant derived category of \ell-adic sheaves on the nilpotent cone of gi\mathfrak{g}_i into blocks, each generated by a certain cuspidal local system via {\itshape spiral inductions}. We prove a conjecture of them, which predicts the bijectivity of a map from 1) the set of simple perverse sheaves in a fixed block to 2) the set of simple modules of a block of a (trigonometric) degenerate double affine Hecke algebra (dDAHA). This is a dDAHA analogue of the Deligne--Langlands correspondence for affine Hecke algebras proven by Kazhdan--Lusztig. Our results generalise a previous work of E. Vasserot, where the perverse sheaves in the principal block were considered.

Keywords

Cite

@article{arxiv.1806.10791,
  title  = {Generalised Springer correspondence for Z/m-graded Lie algebras},
  author = {Wille Liu},
  journal= {arXiv preprint arXiv:1806.10791},
  year   = {2022}
}

Comments

60 pages, major modifications of organisation with respect to last version. To appear in Ann. Sci. \'Ec. Norm. Sup\'er