{ "id": "1612.01776", "version": "v1", "published": "2016-12-06T12:29:16.000Z", "updated": "2016-12-06T12:29:16.000Z", "title": "On completions of Hecke algebras", "authors": [ "Maarten Solleveld" ], "categories": [ "math.RT" ], "abstract": "Let G be a reductive p-adic group and let H(G)^s be a Bernstein block of the Hecke algebra of G. We consider two important topological completions of H(G)^s: a direct summand S(G)^s of the Harish-Chandra--Schwartz algebra of G and a two-sided ideal C*_r (G)^s of the reduced C*-algebra of G. These are useful for the study of all tempered smooth G-representations. We suppose that H(G)^s is Morita equivalent to an affine Hecke algebra H(R,q) -- as is known in many cases. The latter algebra also has a Schwartz completion S(R,q) and a C*-completion C*_r (R,q), both defined in terms of the underlying root datum R and the parameters q. We prove that, under some mild conditions, a Morita equivalence between H(G)^s and H(R,q) extends to Morita equivalences between S(G)^s and S(R,q), and between C*_r (G)^s and C*_r (R,q). We also check that our conditions are fulfilled in all known cases of such Morita equivalences between Hecke algebras.", "revisions": [ { "version": "v1", "updated": "2016-12-06T12:29:16.000Z" } ], "analyses": { "subjects": [ "20C08", "22E50", "22E35" ], "keywords": [ "morita equivalence", "affine hecke algebra", "mild conditions", "root datum", "important topological completions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }