Existence of angular derivative for a class of strip domains

Author:
Swati Sastry

Journal:
Proc. Amer. Math. Soc. **123** (1995), 1075-1082

MSC:
Primary 30C35

MathSciNet review:
1242103

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Abstract: A strip domain *R* is said to have an angular derivative if for each conformal map the limit exists and is finite as . Rodin and Warschawski considerd a class of strip domains for which the euclidean area of is finite, where denotes a Lipschitz approximation of . They showed that a sufficient condition for an angular derivative to exist is that the euclidean area of be finite. We prove that this condition is also necessary.

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DOI:
https://doi.org/10.1090/S0002-9939-1995-1242103-6

Article copyright:
© Copyright 1995
American Mathematical Society