Putnam’s inequality for $p$-hyponormal operators
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- by Muneo Chō and Masuo Itoh
- Proc. Amer. Math. Soc. 123 (1995), 2435-2440
- DOI: https://doi.org/10.1090/S0002-9939-1995-1246519-3
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Abstract:
The purpose of this paper is to show the following: Let $0 < p < \frac {1}{2}$. If T is a p-hyponormal operator on a Hilbert space, then \[ \left \| {{{({T^ \ast }T)}^p} - {{(T{T^ \ast })}^p}} \right \| \leq \frac {p}{\pi }\iint _{\sigma (T)} {{\rho ^{2p - 1}}d\rho d\theta }.\] That is, Putnam’s inequality holds for p-hyponormal operators.References
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Bibliographic Information
- © Copyright 1995 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 123 (1995), 2435-2440
- MSC: Primary 47B20
- DOI: https://doi.org/10.1090/S0002-9939-1995-1246519-3
- MathSciNet review: 1246519