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arXiv · 1503.03800

Constructing minimal homeomorphisms on point-like spaces and a dynamical presentation of the Jiang-Su algebra

Robin J. Deeley·Ian F. Putnam·Karen R. Strung
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Abstract

The principal aim of this paper is to give a dynamical presentation of the Jiang-Su algebra. Originally constructed as an inductive limit of prime dimension drop algebras, the Jiang-Su algebra has gone from being a poorly understood oddity to having a prominent positive role in George Elliott's classification programme for separable, nuclear C*-algebras. Here, we exhibit an etale equivalence relation whose groupoid C*-algebra is isomorphic to the Jiang-Su algebra. The main ingredient is the construction of minimal homeomorphisms on infinite, compact metric spaces, each having the same cohomology as a point. This construction is also of interest in dynamical systems. Any self-map of an infinite, compact space with the same cohomology as a point has Lefschetz number one. Thus, if such a space were also to satisfy some regularity hypothesis (which our examples do not), then the Lefschetz-Hopf Theorem would imply that it does not admit a minimal homeomorphism.

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Robin J. Deeley, Ian F. Putnam, Karen R. Strung. 2015-03-12. Constructing minimal homeomorphisms on point-like spaces and a dynamical presentation of the Jiang-Su algebra. https://arxiv.org/abs/1503.03800

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