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The power inequality on Banach spaces

Published online by Cambridge University Press:  24 October 2008

Béla Bollobás
Béla Bollobás
Affiliation:
Trinity College, Cambridge
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Extract

Let X be a complex normed space with dual space X′ and let T be a bounded linear operator on X. The numerical range of T is defined as

and the numerical radius is v(T) = sup {|ν: νε V(T)}. Most known results and problems concerning numerical range can be found in the notes by Bonsall and Duncan (5).

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 69 , Issue 3 , May 1971 , pp. 411 - 415
Copyright
Copyright © Cambridge Philosophical Society 1971

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References

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