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arXiv · 2307.15571

Norming in Discrete Crossed Products

David R. Pitts·Roger R. Smith·Vrej Zarikian
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Abstract

Let $G \curvearrowright A$ be an action of a discrete group on a unital $C^*$-algebra by $*$-automorphisms. In this note, we give two sufficient dynamical conditions for the $C^*$-inclusion $A \subseteq A \rtimes_r G$ to be norming in the sense of Pop, Sinclair, and Smith. As a consequence of our results, when $A$ is separable or simple, the inclusion $A \subseteq A \rtimes_r G$ is norming provided it has a unique pseudo-expectation in the sense of Pitts.

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David R. Pitts, Roger R. Smith, Vrej Zarikian. 2023-07-28. Norming in Discrete Crossed Products. https://arxiv.org/abs/2307.15571

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