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Sum of two inner functions and exposed points in H1

Published online by Cambridge University Press:  20 January 2009

Takahiko Nakazi
Takahiko Nakazi
Affiliation:
Department of MathematicsFaculty of ScienceHokkaido UniversitySapporo 060Japan
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If h is an outer function in H1 then it is shown that h = (q1 + q2)g where both q1 and q2 are inner functions with Im almost everywhere, and g is a strong outer function (equivalently, g/∥g∥1 is an exposed point of the unit ball of H1). If q1 + q2 is nonconstant then such an h is not strongly outer. Moreover a sum of two inner functions is studied.

Type
Research Article
Information
Proceedings of the Edinburgh Mathematical Society , Volume 35 , Issue 3 , October 1992 , pp. 349 - 357
Copyright
Copyright © Edinburgh Mathematical Society 1992

References

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