Equivariant $\mathcal{O}_2$-absorption theorem for exact groups

Yuhei Suzuki

doi:10.1112/s0010437x21007168

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arXiv · 2004.09461

Equivariant $\mathcal{O}_2$-absorption theorem for exact groups

Yuhei Suzuki

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Abstract

We show that, up to strong cocycle conjugacy, every countable exact group admits a unique equivariantly $\mathcal{O}_2$-absorbing, pointwise outer action on the Cuntz algebra $\mathcal{O}_2$ with the quasi-central approximation property (QAP). In particular, we establish the equivariant analogue of the Kirchberg $\mathcal{O}_2$-absorption theorem for these groups.

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Yuhei Suzuki. 2020-04-20. Equivariant $\mathcal{O}_2$-absorption theorem for exact groups. https://doi.org/10.1112/s0010437x21007168

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