Amplified graph C*-algebras

Søren Eilers; Efren Ruiz; Adam P. W. Sørensen

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arXiv · 1110.2758

Amplified graph C*-algebras

Søren Eilers·Efren Ruiz·Adam P. W. Sørensen

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Abstract

We provide a complete invariant for graph C*-algebras which are amplified in the sense that whenever there is an edge between two vertices, there are infinitely many. The invariant used is the standard primitive ideal space adorned with a map into {-1,0,1,2,...}, and we prove that the classification result is strong in the sense that isomorphisms at the level of the invariant always lift. We extend the classification result to cover more graphs, and give a range result for the invariant (in the vein of Effros-Handelman-Shen) which is further used to prove that extensions of graph C*-algebras associated to amplified graphs are again graph C*-algebras of amplified graphs.

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BibTeX RIS

Søren Eilers, Efren Ruiz, Adam P. W. Sørensen. 2011-10-12. Amplified graph C*-algebras. https://arxiv.org/abs/1110.2758

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