A sharp estimate in an operator inequality

Author:
R. McEachin

Journal:
Proc. Amer. Math. Soc. **115** (1992), 161-165

MSC:
Primary 47A30; Secondary 15A45, 47A55, 47B15

MathSciNet review:
1081093

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Abstract: Let and be Hilbert spaces, and suppose and are selfadjoint operators with . It is known that for any we must have . In this paper we give examples proving that is sharp in this inequality.

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Additional Information

DOI:
https://doi.org/10.1090/S0002-9939-1992-1081093-3

Article copyright:
© Copyright 1992
American Mathematical Society