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arXiv · 1912.12727

A rigid hyperfinite type $\mathrm{II}_1$ factor

Ilijas Farah·Ilan Hirshberg
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Abstract

We show that it is relatively consistent with ZFC that there exists a hyperfinite type $\mathrm{II}_1$-factor of density character $\aleph_1$ which is not isomorphic to its opposite, does not have any outer automorphisms, and has trivial fundamental group.

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Ilijas Farah, Ilan Hirshberg. 2020-02-27. A rigid hyperfinite type $\mathrm{II}_1$ factor. https://doi.org/10.1093/imrn%2Frnaa067

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