Essential numerical range in $B(l_{1})$
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- by D. A. Legg and D. W. Townsend PDF
- Proc. Amer. Math. Soc. 81 (1981), 541-545 Request permission
Abstract:
In recent years, the numerical range lifting problem has been solved for operators on ${l_p}$, $1 < p < \infty$, and on certain Orlicz spaces ${l_M}$. Specifically, given an operator $A$, there exists a compact perturbation $A + C$ such that the numerical range of $A + C$ equals the essential numerical range of $A$. This result has also been established for essentially Hermitian operators on ${l_1}$. In the present paper, the authors establish this result for all operators on ${l_1}$.References
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Additional Information
- © Copyright 1981 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 81 (1981), 541-545
- MSC: Primary 47A12
- DOI: https://doi.org/10.1090/S0002-9939-1981-0601725-3
- MathSciNet review: 601725