Numerical radius preserving operators on

Author:
Jor-Ting Chan

Journal:
Proc. Amer. Math. Soc. **123** (1995), 1437-1439

MSC:
Primary 47A12; Secondary 47B49

DOI:
https://doi.org/10.1090/S0002-9939-1995-1231293-7

MathSciNet review:
1231293

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Abstract: Let *H* be a Hilbert space over and let denote the vector space of all bounded linear operators on *H*. We prove that a linear isomorphism is numerical radius-preserving if and only if it is a multiply of a -isomorphism by a scalar of modulus one.

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DOI:
https://doi.org/10.1090/S0002-9939-1995-1231293-7

Article copyright:
© Copyright 1995
American Mathematical Society