On the Connes–Kasparov isomorphism, I

Pierre Clare1, Nigel Higson2, Yanli Song3, Xiang Tang3
1College of William & Mary, Williamsburg, USA
2Penn State University, University Park, USA
3Washington University in St. Louis, St. Louis, USA

Tóm tắt

This is the first of two papers dedicated to the detailed determination of the reduced C*-algebra of a connected, linear, real reductive group up to Morita equivalence, and a new and very explicit proof of the Connes–Kasparov conjecture for these groups using representation theory. In this part we shall give details of the C*-algebraic Morita equivalence and then explain how the Connes–Kasparov morphism in operator K-theory may be computed using what we call the Matching Theorem, which is a purely representation-theoretic result. We shall prove our Matching Theorem in the sequel, and indeed go further by giving a simple, direct construction of the components of the tempered dual that have non-trivial K-theory using David Vogan’s approach to the classification of the tempered dual.

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