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arXiv · 1309.1070

Automorphisms of Cuntz-Krieger algebras

Søren Eilers·Gunnar Restorff·Efren Ruiz
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Abstract

We prove that the natural homomorphism from Kirchberg's ideal-related KK-theory, KKE(e, e'), with one specified ideal, into Hom_{\Lambda} (\underline{K}_{E} (e), \underline{K}_{E} (e')) is an isomorphism for all extensions e and e' of separable, nuclear C*-algebras in the bootstrap category N with the K-groups of the associated cyclic six term exact sequence being finitely generated, having zero exponential map and with the K_{1}-groups of the quotients being free abelian groups. This class includes all Cuntz-Krieger algebras with exactly one non-trivial ideal. Combining our results with the results of Kirchberg, we classify automorphisms of the stabilized purely infinite Cuntz-Krieger algebras with exactly one non-trivial ideal modulo asymptotically unitary equivalence. We also get a classification result modulo approximately unitary equivalence. The results in this paper also apply to certain graph algebras.

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Søren Eilers, Gunnar Restorff, Efren Ruiz. 2013-09-04. Automorphisms of Cuntz-Krieger algebras. https://doi.org/10.4171/jncg%2F275

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