On the essential numerical range of a generalized derivation
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- by Bojan Magajna PDF
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Abstract:
Let $A$ and $B$ be bounded operators on Hilbert spaces $\mathcal {H}$ and $\mathcal {L}$, respectively. The essential numerical range of the operator $X \to AX - XB$, defined on the Hilbert-Schmidt class ${\mathcal {C}^2}\left ( {\mathcal {L},\mathcal {H}} \right )$ is expressed in terms of the numerical and the essential numerical ranges of $A$ and $B$.References
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Additional Information
- © Copyright 1987 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 99 (1987), 86-92
- MSC: Primary 47B47; Secondary 47A12
- DOI: https://doi.org/10.1090/S0002-9939-1987-0866435-1
- MathSciNet review: 866435