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The spectra of Toeplitz operators with unimodular symbols

Published online by Cambridge University Press:  20 January 2009

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

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The spectrum σ(Tφ) of a Toeplitz operator Tφ on the open unit disc D for a unimodular symbol φ is studied and many sufficient conditions for σ(Tφ)⊆∂D or σ(Tφ) = are given. In particular if φ is a unimodular function in H + C, then σ(Tφ)⊆∂D or σ(Tφ) =

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1998

References

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