Hermitian forms for affine Hecke algebras

Abstract

We study star operations for Iwahori-Hecke algebras and invariant hermitian forms for finite dimensional modules over (graded) affine Hecke algebras with a view towards a unitarity algorithm.Comment: 29 pages, preliminary version. v2: the classification of star operations for the graded Hecke algebras and the construction of hermitian forms in the Iwahori case via Bernstein's projectives have been removed from this preprint and they will make the basis of a new pape