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ArticleOriginal scientific text

Title

Perturbation theorems for Hermitian elements in Banach algebras

Authors 1, 2

Affiliations

  1. Indian Statistical Institute, New Delhi 110 016, India
  2. Department of Mathematics, Kuwait University, P.O. Box 5969, Safat 13060, Kuwait

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.

Keywords

ENG
Banach algebra, Hermitian element, spectral radius

Bibliography

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Studia Mathematica
1999/134/2
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Pages:
111-117
Main language of publication
English
Received
1997-07-02
Accepted
1998-10-13
Published
1999
Exact and natural sciences