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Absolute Values of Toeplitz Operators and Hankel Operators

Published online by Cambridge University Press:  20 November 2018

Takahiko Nakazi*
Affiliation:
Department of Mathematics, Faculty of Science, Hokkaido University, Sapporo 060, Japan
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Abstract

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Nehari's theorem for norms of bounded Hankel operators is revisited. Using it, the absolute values of Toeplitz operators are studied. This gives a theorem of Widom and Devinatz for invertible Toeplitz operators.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1991

References

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