English

Analytic R-groups of affine Hecke algebras

Representation Theory 2010-09-01 v2

Abstract

We define analytic RR-groups for affine Hecke algebras, and prove the analog of the Knapp-Stein Dimension Theorem. As a corollary we prove that the commutant algebra of a unitary principal series representation is isomorphic to the complex group algebra of the RR-group, twisted by a certain 2-cocycle γ\gamma. For classical Hecke algebras we prove that γ\gamma is always trivial.

Keywords

Cite

@article{arxiv.0909.1227,
  title  = {Analytic R-groups of affine Hecke algebras},
  author = {Eric Opdam and Patrick Delorme},
  journal= {arXiv preprint arXiv:0909.1227},
  year   = {2010}
}

Comments

Some improvements in the presentation were made, and an example has been added showing the nontriviality of the cohomology class of the 2-cocycle $\gamma_\Delta$ (as opposed to $\gamma$ itself) for Hecke algebras of type D