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arXiv · 1911.07377

Some Results and a K-theory Problem about Threshold Commutants mod Normed Ideals

Dan-Virgil Voiculescu
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Abstract

We extend to the case of a threshold ideal our result with J. Bourgain about the essential centre of the commutant mod a diagonalization ideal for a n-tuple of commuting Hermitian operators . We also compute the $K_0$-group of the commutant mod trace-class of a unitary operator with spectrum equal to its essential spectrum. We present the problem of computing the $K_1$-group for a commutant mod trace-class in its simplest case.

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Dan-Virgil Voiculescu. 2019-11-18. Some Results and a K-theory Problem about Threshold Commutants mod Normed Ideals. https://arxiv.org/abs/1911.07377

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