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arXiv · 2505.16759

On the inclusion $\cO_2 \subset \cQ_2$

Jacopo Bassi·Roberto Conti
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Abstract

The diadic $C^*$-algebra $\cQ_2$ contains canonically a copy of the Cuntz algebra $\cO_2$. It is shown that the inclusion $\cO_2 \subset \cQ_2$ is $C^*$-irreducible and rigid. It follows that the injective envelopes of these two $C^*$-algebras are $*$-isomorphic.

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Jacopo Bassi, Roberto Conti. 2025-05-22. On the inclusion $\cO_2 \subset \cQ_2$. https://arxiv.org/abs/2505.16759

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