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arXiv · 2401.07785

Maximal amenability of the radial subalgebra in free quantum group factors

Roland Vergnioux·Xumin Wang
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Abstract

We show that the radial MASA in the orthogonal free quantum group algebra L(FO_N) is maximal amenable if N is large enough, using the Asymptotic Orthogonality Property. This relies on a detailed study of the corresponding bimodule, for which we construct in particular a quantum analogue of R\u{a}dulescu's basis. As a byproduct we also obtain the value of the Puk\'anszky invariant for this MASA.

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Roland Vergnioux, Xumin Wang. 2024-01-15. Maximal amenability of the radial subalgebra in free quantum group factors. https://arxiv.org/abs/2401.07785

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