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Contractible subgraphs and Morita equivalence of graph C*-algebras

Tyrone Crisp·Daniel Gow
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Abstract

In this paper we describe an operation on directed graphs which produces a graph with fewer vertices, such that the C*-algebra of the new graph is Morita equivalent to that of the original graph. We unify and generalize several related constructions, notably delays and desingularizations of directed graphs.

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Tyrone Crisp, Daniel Gow. 2004-04-29. Contractible subgraphs and Morita equivalence of graph C*-algebras. https://arxiv.org/abs/math/0404542

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