Perturbation theorems for Hermitian elements in Banach algebras

Rajendra Bhatia; Driss Drissi

Studia Mathematica (1999)

  • Volume: 134, Issue: 2, page 111-117
  • ISSN: 0039-3223

Abstract

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Two well-known theorems for Hermitian elements in C*-algebras are extended to Banach algebras. The first concerns the solution of the equation ax - xb = y, and the second gives sharp bounds for the distance between spectra of a and b when a, b are Hermitian.

How to cite

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Bhatia, Rajendra, and Drissi, Driss. "Perturbation theorems for Hermitian elements in Banach algebras." Studia Mathematica 134.2 (1999): 111-117. <http://eudml.org/doc/216625>.

@article{Bhatia1999,
abstract = {Two well-known theorems for Hermitian elements in C*-algebras are extended to Banach algebras. The first concerns the solution of the equation ax - xb = y, and the second gives sharp bounds for the distance between spectra of a and b when a, b are Hermitian.},
author = {Bhatia, Rajendra, Drissi, Driss},
journal = {Studia Mathematica},
keywords = {Banach algebra; Hermitian element; spectral radius; Hausdorff distance between spectra; Hermitian elements; complex unital Banach algebra; integral representation},
language = {eng},
number = {2},
pages = {111-117},
title = {Perturbation theorems for Hermitian elements in Banach algebras},
url = {http://eudml.org/doc/216625},
volume = {134},
year = {1999},
}

TY - JOUR
AU - Bhatia, Rajendra
AU - Drissi, Driss
TI - Perturbation theorems for Hermitian elements in Banach algebras
JO - Studia Mathematica
PY - 1999
VL - 134
IS - 2
SP - 111
EP - 117
AB - Two well-known theorems for Hermitian elements in C*-algebras are extended to Banach algebras. The first concerns the solution of the equation ax - xb = y, and the second gives sharp bounds for the distance between spectra of a and b when a, b are Hermitian.
LA - eng
KW - Banach algebra; Hermitian element; spectral radius; Hausdorff distance between spectra; Hermitian elements; complex unital Banach algebra; integral representation
UR - http://eudml.org/doc/216625
ER -

References

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  14. [14] R. McEachin, A sharp estimate in an operator inequality, Proc. Amer. Math. Soc. 115 (1992), 161-165. Zbl0757.47014
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