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arXiv · 0808.3763

The commutant of L(H) in its ultrapower may or may not be trivial

Ilijas Farah·N. Christopher Phillips·Juris Steprāns
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Abstract

Kirchberg asked in 2004 whether the commutant of L(H)$ in its (norm) ultrapower is trivial. Assuming the Continnuum Hypothesis, we prove that the answer depends on the choice of the ultrafilter.

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Ilijas Farah, N. Christopher Phillips, Juris Steprāns. 2009-10-01. The commutant of L(H) in its ultrapower may or may not be trivial. https://arxiv.org/abs/0808.3763

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