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Twisted crossed products of C*-algebras

Published online by Cambridge University Press:  28 June 2011

Judith A. Packer
Affiliation:
Department of Mathematics, National University of Singapore, Kent Ridge, Singapore 0511
Iain Raeburn
Affiliation:
School of Mathematics, University of New South Wales, P.O. Box 1, Kensington, NSW 2033, Australia and Department of Mathematics, University of Edinburgh, The King's Buildings, Mayfield Road, Edinburgh EH9 3JZ, Scotland

Extract

Group algebras and crossed products have always played an important role in the theory of C*-algebras, and there has also been considerable interest in various twisted analogues, where the multiplication is twisted by a two-cocycle. Here we shall discuss a very general family of twisted actions of locally compact groups on C*-algebras, and the corresponding twisted crossed product C*-algebras. We shall then establish some of the basic properties of these algebras, motivated by the requirements of some applications we have in mind [2, 9, 10]. Some of our results will be known to others, at least in principle, but we feel that a coherent account might be useful.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1989

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