The cocenter of graded affine Hecke algebra and the density theorem

ArticleinJournal of Pure and Applied Algebra 220(1) · August 2012with 12 Reads 
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Abstract
We determine a basis of the (twisted) cocenter of graded affine Hecke algebras with arbitrary parameters. In this setting, we prove that the kernel of the (twisted) trace map is the commutator subspace (Density theorem) and that the image is the space of good forms (trace Paley-Wiener theorem).

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