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Almost commuting unitary matrices


Authors: Ruy Exel and Terry Loring
Journal: Proc. Amer. Math. Soc. 106 (1989), 913-915
MSC: Primary 15A15; Secondary 15A27, 47A55, 47B47, 55M25
DOI: https://doi.org/10.1090/S0002-9939-1989-0975641-9
MathSciNet review: 975641
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Abstract: A pair of square matrices is said to be almost commuting if their commutator is small in norm. We give an elementary proof of a theorem of Voiculescu showing that not all almost commuting pairs can be perturbed to a commuting pair.


References [Enhancements On Off] (What's this?)

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Additional Information

DOI: https://doi.org/10.1090/S0002-9939-1989-0975641-9
Article copyright: © Copyright 1989 American Mathematical Society

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