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arXiv · 2012.02830

Simultaneous averaging to zero by unitary mixing operators

Abhinav Chand·Leonel Robert·Arindam Sutradhar
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Abstract

We show that if every element a vector subspace of a C*-algebra can be averaged to zero by means of unitary mixing operators, then all the elements of the subspace can be simultaneously averaged to zero by a net of unitary mixing operators. Moreover, such subspaces admit a simple description in terms of commutators and kernels of states on the C*-algebra. We apply this result to center-valued expectations in C*-algebras with the Dixmier property.

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Abhinav Chand, Leonel Robert, Arindam Sutradhar. 2020-12-04. Simultaneous averaging to zero by unitary mixing operators. https://arxiv.org/abs/2012.02830

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