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Hilbert C*-modules and conditional expectations on crossed products

Part of: Selfadjoint operator algebras Topological algebras, normed rings and algebras, Banach algebras

Published online by Cambridge University Press:  09 April 2009

Mahmood Khoshkam
Mahmood Khoshkam
Affiliation:
Department of Mathematics and Statistics University of Saskatchewan106 Wiggins Road Saskatoon, SK S7N 5E6Canada e-mail: khoshkam@math.usask.ca
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Abstract

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In this paper, we study the structure of certain conditional expectation on crossed product C*-algebra. In particular, we prove that the index of a conditional expectation E: B → A is finite if and only if the index of the induced expectation from B ⋊ G onto A ⋊ G is finite where G is a discrete group acting on B.

MSC classification

Secondary: 46L05: General theory of $C^*$-algebras 46H25: Normed modules and Banach modules, topological modules (if not placed in or )
Type
Research Article
Information
Journal of the Australian Mathematical Society , Volume 61 , Issue 1 , August 1996 , pp. 106 - 118
Copyright
Copyright © Australian Mathematical Society 1996

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