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arXiv · 2108.02168

On the commutant of $B(H)$ in its ultrapower

Emmanuel Chetcuti·Beatriz Zamora-Aviles
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Abstract

Let $B(H)$ be the algebra of bounded linear operators on a separable infinite-dimensional Hilbert space $H$. We study the commutant of $B(H)$ in its ultrapower. We characterize the class of non-principal ultrafilters for which this commutant is non-trivial. Additionally, we extend the class of ultrafilters for which the commutant is trivial.

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Emmanuel Chetcuti, Beatriz Zamora-Aviles. 2021-08-04. On the commutant of $B(H)$ in its ultrapower. https://arxiv.org/abs/2108.02168

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