Nearest normal approximation for certain operators
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- by John Phillips PDF
- Proc. Amer. Math. Soc. 67 (1977), 236-240 Request permission
Abstract:
In this paper we show that binormal operators have nearest normal approximants. In fact, we exhibit nearest normals to such operators and, as a corollary, show that the hermitian part of a binormal operator with real spectrum is a nearest normal. We obtain further corollaries on nearest normal approximation to operators which are square roots of normal operators and then apply these results to perturbations of operator algebras.References
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Additional Information
- © Copyright 1977 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 67 (1977), 236-240
- MSC: Primary 47A55; Secondary 47B20
- DOI: https://doi.org/10.1090/S0002-9939-1977-0458212-4
- MathSciNet review: 0458212