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arXiv · 2309.11068

Endomorphisms of Z-absorbing C*-algebras without conditional expectations

Yasuhiko Sato
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Abstract

We construct an endomorphism of the Jiang-Su algebra $\mathcal{Z}$ which does not admit a conditional expectation. This answers a question in the testamentary homework by E. Kirchberg. As an application, it is shown that any unital separable nuclear $\mathcal{Z}$-absorbing C*-algebra is non-transportable in the Cuntz algebra $\mathcal{O}_2$.

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Yasuhiko Sato. 2023-09-20. Endomorphisms of Z-absorbing C*-algebras without conditional expectations. https://arxiv.org/abs/2309.11068

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