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arXiv · 1207.5527

Ideal-related K-theory for Leavitt path algebras and graph C*-algebras

Efren Ruiz·Mark Tomforde
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Abstract

We introduce a notion of ideal-related K-theory for rings, and use it to prove that if two complex Leavitt path algebras are Morita equivalent (respectively, isomorphic), then the ideal-related K-theories (respectively, the unital ideal-related K-theories) of the corresponding graph C*-algebras are isomorphic. This has consequences for the "Morita equivalence conjecture" and "isomorphism conjecture" for graph algebras, and allows us to prove that when E and F belong to specific collections of graphs whose C*-algebras are classified by ideal-related K-theory, Morita equivalence (respectively, isomorphism) of the Leavitt path algebras implies strong Morita equivalence (respectively, isomorphism) of the graph C*-algebras. We state a number of corollaries that describe various classes of graphs where these implications hold. In addition, we conclude with a classification of Leavitt path algebras of amplified graphs similar to the existing classification for graph C*-algebras of amplified graphs.

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Efren Ruiz, Mark Tomforde. 2012-07-23. Ideal-related K-theory for Leavitt path algebras and graph C*-algebras. https://arxiv.org/abs/1207.5527

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