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arXiv · 2607.28597

Nonnuclear Bunce-Deddens algebras

Jamie Bell
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Abstract

We introduce nonnuclear Bunce-Deddens algebras, defined as reduced crossed product C*-algebras associated with free odometer actions of nonamenable countable discrete residually finite groups on a Cantor space. These are nonnuclear counterparts to the generalised Bunce-Deddens algebras introduced by Orfanos. For large classes of groups, we show that they share many regularity properties, including real rank zero, stable rank one, strict comparison of positive elements, and admitting a unique tracial state. In many cases, we deduce that they are even selfless and hence pure. Finally, we compute the K-theory of Bunce-Deddens algebras over nonabelian free groups.

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Jamie Bell. 2026-07-30. Nonnuclear Bunce-Deddens algebras. https://arxiv.org/abs/2607.28597

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