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arXiv · 1608.07228

Lebesgue decomposition of functionals and unique preduals for commutants modulo normed ideals

Dan-Virgil Voiculescu
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Abstract

We prove an analogue of the Lebesgue decomposition for continuous functionals on the commutant modulo a reflexive normed ideal of an n-tuple of hermitian operators for which there are quasicentral approximate units relative to the normed ideal. Using results of Godefroy-Talagrand and Pfitzner we derive from this strong uniqueness of the predual of such a commutant modulo a normed ideal.

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Dan-Virgil Voiculescu. 2016-08-25. Lebesgue decomposition of functionals and unique preduals for commutants modulo normed ideals. https://arxiv.org/abs/1608.07228

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