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Group actions on topological graphs

Published online by Cambridge University Press:  16 September 2011

VALENTIN DEACONU
Affiliation:
Department of Mathematics, University of Nevada, Reno, NV 89557-0084, USA (email: [email protected], [email protected])
ALEX KUMJIAN
Affiliation:
Department of Mathematics, University of Nevada, Reno, NV 89557-0084, USA (email: [email protected], [email protected])
JOHN QUIGG
Affiliation:
School of Mathematical and Statistical Sciences, Arizona State University, Tempe, AZ 85287-1804, USA (email: [email protected])

Abstract

We define the action of a locally compact group G on a topological graph E. This action induces a natural action of G on the C*-correspondence ℋ(E) and on the graph C*-algebra C*(E). If the action is free and proper, we prove that C*(E)⋊rG is strongly Morita equivalent to C*(E/G) . We define the skew product of a locally compact group G by a topological graph E via a cocycle c:E1G. The group acts freely and properly on this new topological graph E×cG. If G is abelian, there is a dual action on C* (E) such that . We also define the fundamental group and the universal covering of a topological graph.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2011

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