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Classification of minimal actions of a compact Kac algebra with amenable dual

Toshihiko Masuda·Reiji Tomatsu
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Abstract

We show the uniqueness of minimal actions of a compact Kac algebra with amenable dual on the AFD factor of type II$_1$. This particularly implies the uniqueness of minimal actions of a compact group. Our main tools are a Rohlin type theorem, the 2-cohomology vanishing theorem, and the Evans-Kishimoto type intertwining argument.

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Toshihiko Masuda, Reiji Tomatsu. 2006-11-14. Classification of minimal actions of a compact Kac algebra with amenable dual. https://doi.org/10.1007/s00220-007-0269-4

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