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Orthonormal systems in Banach spaces and their applications

Published online by Cambridge University Press:  24 October 2008

N. J. Kalton
Affiliation:
University College, Swansea
G. V. Wood
Affiliation:
University College, Swansea

Extract

By an orthonormal system in a general complex Banach space, we mean a collection {eα: α ∈ } it vectors such that, for each α, there is an hermitian (in the numerical range sense, see (4)) projection Pα whose range is lin (eα) and such that PαPβ = 0, if α ≠ β. This paper is devoted to the study of orthonormal systems in general Banach spaces, and their applications to problems of characterizing isometries and hermitian operators.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1976

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