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Simple C*-crossed products with a unique trace

Published online by Cambridge University Press:  19 September 2008

Erik Bédos
Affiliation:
Department of Mathematics, University of Oslo, P.b. 1053, 0316 Oslo, Norway

Abstract

Let (α, u) denote a cocycle-crossed action of a discrete group G on a unital C*-algebra A, and B = C*r (A, G, α, u) the associated reduced (twisted) C*-crossed product. We discuss the following problem: when is B a simple C*-algebra with a unique trace? To this aim, we introduce the concept of tracially properly outerness of actions.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1996

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