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Operators preserving orthogonality are isometries

Published online by Cambridge University Press:  14 November 2011

Alexander Koldobsky
Affiliation:
University of Texas at San Antonio, Division of Mathematics, Computer Science, and Statistics, San Antonio, TX 78249, U.S.A

Synopsis

We prove that every operator preserving orthogonality in a real Banach space is an isometry multiplied by a constant.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1993

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