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Proceedings of the American Mathematical Society

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On proximinal sets of normal operators


Author: Donald D. Rogers
Journal: Proc. Amer. Math. Soc. 61 (1976), 44-48
MSC: Primary 47B15
DOI: https://doi.org/10.1090/S0002-9939-1976-0451018-0
MathSciNet review: 0451018
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Abstract: It is shown that neither the set of normal operators nor the set of orthogonal projections is a proximinal subset of the space of bounded operators on an infinite-dimensional Hilbert space.


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

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Additional Information

DOI: https://doi.org/10.1090/S0002-9939-1976-0451018-0
Keywords: Normal operator, hyponormal operator, projection, proximinal set
Article copyright: © Copyright 1976 American Mathematical Society

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