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arXiv · 0910.4719

Subshifts and C*-algebras from one-counter codes

Wolfgang Krieger·Kengo Matsumoto
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Abstract

We introduce a class of subshifts under the name of "standard one-counter shifts". The standard one-counter shifts are the Markov coded systems of certain Markov codes that belong to the family of one-counter languages. We study topological conjugacy and flow equivalence of standard one-counter shifts. To subshifts there are associated C*-algebras by their $λ$-graph systems. We describe a class of standard one-counter shifts with the property that the C*-algebra associated to them is simple, while the C*-algebra that is associated to their inverse is not. This gives examples of subshifts that are not flow equivalent to their inverse. For a family of highly structured standard one-counter shifts we compute the K-groups.

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Wolfgang Krieger, Kengo Matsumoto. 2009-10-25. Subshifts and C*-algebras from one-counter codes. https://arxiv.org/abs/0910.4719

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