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arXiv · 1804.09515

Strong uncountable cofinality for unitary groups of von Neumann algebras

Philip A. Dowerk
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Abstract

We show that unitary groups of II$_1$ factors and of properly infinite von Neumann algebras have strong uncountable cofinality. In particular, we obtain a short alternative proof for the strong uncountable cofinality of $U(\ell^2(\mathbb{N}))$, which was first proven by Ricard and Rosendal.

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Philip A. Dowerk. 2018-04-25. Strong uncountable cofinality for unitary groups of von Neumann algebras. https://arxiv.org/abs/1804.09515

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