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arXiv · 2604.18410

Crossed product C*-algebras associated with non-minimal actions on the circle

Jamie Bell
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Abstract

We examine crossed product C*-algebras associated with free non-minimal actions of countably infinite discrete abelian groups on the circle, extending the work of Putnam, Schmidt, and Skau. We obtain a large class of unital separable nuclear and non-simple C*-algebras that are quasidiagonal, have stable rank one, and admit a unique tracial state. We determine their ideal structure and establish an improved uniform upper bound for their nuclear dimension. Finally, in the case $G = \mathbb{Z}^d$, we compute the K-theory and trace pairing map.

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Jamie Bell. 2026-07-07. Crossed product C*-algebras associated with non-minimal actions on the circle. https://arxiv.org/abs/2604.18410

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