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Spatial numerical range of an operator

Published online by Cambridge University Press:  24 October 2008

K. Tillekeratne
K. Tillekeratne
Affiliation:
Churchill College, Cambridge and University of Ceylon, Peradeniya, Ceylon
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Extract

0. Introduction. Let X be a normed space and let T be an operator on X. Let S(X) denote its unit sphere, {x ∈ X: ∥x∥ = 1}, B(X) = {x ∈ X: ∥x∥ ≤ 1} its unit ball, X′ its dual and ℬ(X) the normed algebra of bounded linear operators on X. Let II be the subset of the Cartesian product X × X′ defined by

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 76 , Issue 3 , November 1974 , pp. 515 - 520
Copyright
Copyright © Cambridge Philosophical Society 1974

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References

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