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Existence of solutions of extremal problems in H1

Published online by Cambridge University Press:  20 January 2009

Takahiko Nakazi
Takahiko Nakazi
Affiliation:
Department of MathematicsFaculty of ScienceHokkaido UniversitySappro 060, Japan
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Abstract

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An essentially bounded function on the unit circle gives a continuous linear functional on the Hardy space H1. In this paper we study when there exists at least one function which attains its norm. We apply the results to an interpolation problem, Hankel operators and a characterization of exposed points of the closed unit ball of H1.

Type
Research Article
Information
Proceedings of the Edinburgh Mathematical Society , Volume 34 , Issue 1 , February 1991 , pp. 99 - 112
Copyright
Copyright © Edinburgh Mathematical Society 1991

References

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