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

  • Selçuk Barlak
  • Gábor Szabó


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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How to Cite
Barlak, S., & Szabó, G. (2019). On diagonal quasi-free automorphisms of simple Cuntz-Krieger algebras. MATHEMATICA SCANDINAVICA, 125(2), 210-226. https://doi.org/10.7146/math.scand.a-114823