Model actions for almost reduced groups on UHF algebras

Michael Sun

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arXiv · 1409.7093

Model actions for almost reduced groups on UHF algebras

Michael Sun

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Abstract

For any countable discrete group $G$ with a reduced abelian subgroup of finite index, we construct an action $\alpha$ of $G$ on the universal UHF algebra $\Qq$ using an infinite tensor product of permutation representations of $G$ and show that these actions possess some sort of Rokhlin property. The crossed product $\qag$ is then deduced to be tracially AF with a unique tracial state. We also compute the Elliott invariants in the case that $G$ is abelian.

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Michael Sun. 2014-09-24. Model actions for almost reduced groups on UHF algebras. https://arxiv.org/abs/1409.7093

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