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arXiv · 1809.08810

Rigid sides of approximately finite dimensional simple operator algebras in non-separable category

Yuhei Suzuki
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Abstract

Applying Popa's orthogonality method to a new class of groups, we construct amenable group factors which are prime and have no infinite dimensional regular abelian *-subalgebras. By adjusting Farah--Katsura's solution of Dixmier's problem to the von Neumann algebra setting, we obtain the first examples of prime AFD factors and tensorially prime simple AF-algebras. Our results are proved in ZFC, thus in particular answering questions asked by Farah--Hathaway--Katsura--Tikuisis. We also directly determine central sequences of certain crossed products. This concludes the failure of the Kirchberg $\mathcal{O}_\infty$-absorption theorem in the non-separable setting.

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Yuhei Suzuki. 2019-03-28. Rigid sides of approximately finite dimensional simple operator algebras in non-separable category. https://doi.org/10.1093/imrn%2Frnz079

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