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arXiv · 2103.04695

AT-algebras from fiberwise essentially minimal zero-dimensional dynamical systems

Paul Herstedt
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Abstract

We introduce a type of zero-dimensional dynamical system (a pair consisting of a totally disconnected compact metrizable space along with a homeomorphism of that space), which we call "fiberwise essentially minimal", and we prove that the associated crossed product $ C^* $-algebra of such a system is an AT-algebra. Under the additional assumption that the system has no periodic points, we prove that the associated crossed product $ C^* $-algebra has real rank zero, which tells us that such $ C^* $-algebras are classifiable by $ K $-theory. We show that the definition of fiberwise essentially minimality allows one to produce many nontrivial examples of such systems (ones that are neither minimal nor essentially minimal). The associated crossed product $ C^* $-algebras to these nontrivial examples are of particular interest because they are non-simple (unlike in the minimal case).

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Paul Herstedt. 2021-03-08. AT-algebras from fiberwise essentially minimal zero-dimensional dynamical systems. https://arxiv.org/abs/2103.04695

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