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arXiv · 1708.08258

On diagonal quasi-free automorphisms of simple Cuntz-Krieger algebras

Selçuk Barlak·Gábor Szabó
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Abstract

We show that an outer action of a finite abelian group on a simple Cuntz-Krieger algebra is strongly approximately inner in the sense of Izumi if the action is given by diagonal quasi-free automorphisms and the associated matrix is aperiodic. This is achieved by an approximate cohomology vanishing-type argument for the canonical shift restricted to the relative commutant of the set of domain projections of the canonical generating isometries in the fixed point algebra.

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Selçuk Barlak, Gábor Szabó. 2017-08-28. On diagonal quasi-free automorphisms of simple Cuntz-Krieger algebras. https://doi.org/10.7146/math.scand.a-114823

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