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Ext classes and embeddings for C*-algebras of graphs with sinks

Mark Tomforde
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Abstract

We consider directed graphs E which have been obtained by adding a sink to a fixed graph G. We associate an element of Ext(C*(G)) to each such E, and show that the classes of two such graphs are equal in Ext(C*(G)) if and only if the associated C*-algebra of one can be embedded as a full corner in the C*-algebra of the other in a particular way. If every loop in G has an exit, then we are able to use this result to generalize some of the classification theorems of Raeburn, Tomforde, and Williams for C*-algebras of graphs with sinks.

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Mark Tomforde. 2001-11-06. Ext classes and embeddings for C*-algebras of graphs with sinks. https://arxiv.org/abs/math/0103056

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