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Spectra of operators with fixed imaginary parts


Author: Andrzej Pokrzywa
Journal: Proc. Amer. Math. Soc. 81 (1981), 359-364
MSC: Primary 15A18; Secondary 15A42, 15A60, 47A10
DOI: https://doi.org/10.1090/S0002-9939-1981-0597640-4
MathSciNet review: 597640
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Abstract: The aim of this paper is to obtain the best bound for the distance between the eigenvalues of a Hermitian matrix $ B$ and the real parts of eigenvalues of a matrix $ B + iA$, where $ A$ is also Hermitian, in the terms of eigenvalues of $ A$. A similar problem in infinite-dimensional Hilbert space is also considered.


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Additional Information

DOI: https://doi.org/10.1090/S0002-9939-1981-0597640-4
Article copyright: © Copyright 1981 American Mathematical Society

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