English

Discrete series for the graded Hecke algebra of type $H_{4}$

Representation Theory 2025-07-29 v2 Number Theory

Abstract

This article confirms the prediction that the set of discrete series central character for the graded (affine) Hecke algebra of type H4H_4 coincides with the set of the Heckman-Opdam central characters. Combining with previous cases of Kazhdan-Lusztig, Kriloff, Kriloff-Ram, Opdam-Solleveld, Ciubotaru-Opdam, this completes the classification of discrete series for all the graded Hecke algebras of positive parameters. Main tools include construction of calibrated modules and construction of certain minimally induced modules for discrete series. We also study the anti-sphericiity and Ext-branching laws for some discrete series.

Keywords

Cite

@article{arxiv.2504.21790,
  title  = {Discrete series for the graded Hecke algebra of type $H_{4}$},
  author = {Kei Yuen Chan and Simeng Huang},
  journal= {arXiv preprint arXiv:2504.21790},
  year   = {2025}
}

Comments

39 pages+13 pages Appendix on computations and diagrams, v2: added Section 17 and fixed some typos