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Cocycles and representations of groups of CAR type

Published online by Cambridge University Press:  09 April 2009

A. L. Carey
Affiliation:
Department of Mathematics, Institute of Advanced Studies, Australian National University, Canberra A.C.T., Australia
William Moran
Affiliation:
Department of Mathematics, University of Adelaide, Adelaide S.A., Australia
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Abstract

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Representations of non-type I groups G which may be expressed as an increasing union of type I normal subgroups are considered. Groups with this structure are natural generalisations of the CAR algebra (viewed as a twisted group C*-algebra) and are also group theoretic analogues of AF algebras. This paper gives a systematic account of their representation theory based on a canonical construction of one-cocycles for the G-action on the dual of a normal subgroup. Some examples are considered showing how to construct inquivalent irreducible representations (non-cohomologous cocycles) and also factor representations by a method which generalises the well-known construction of non-isomorphic factors for the CAR algebra.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1986

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