The numerical index of nonselfadjoint operator algebras
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- by Yoshihiro Nakamura, Kichi-Suke Saito and Kazunari Sakaba PDF
- Proc. Amer. Math. Soc. 117 (1993), 1105-1107 Request permission
Abstract:
Let $\mathfrak {A}$ be a (not necessarily selfadjoint) closed subalgebra of $B(H)$ that is the algebra of all bounded linear operators on a Hilbert space $H$. In this note, we prove that the range of numerical index of $\mathfrak {A}$ as an algebra is the whole of the interval $[\tfrac {1} {2},1]$.References
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Additional Information
- © Copyright 1993 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 117 (1993), 1105-1107
- MSC: Primary 47D25; Secondary 46L99, 47A12
- DOI: https://doi.org/10.1090/S0002-9939-1993-1118086-4
- MathSciNet review: 1118086