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arXiv · 1510.04886

Univalence criterion for harmonic mappings and $\Phi$-like functions

Sergey Yu. Graf·Saminathan Ponnusamy·Victor V. Starkov
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Abstract

In this paper, we obtain a new characterization for univalent harmonic mappings and obtain a structural formula for the associated function which defines the analytic $\Phi$-like functions in the unit disk. The new criterion stated in this article for the injectivity of harmonic mappings implies the well-known results of Kas'yanyuk \cite{Kas59} and Brickman \cite{Brick73} for analytic functions, but with a simpler proof than theirs. A number of consequences of the characterization, and examples are also presented. Further investigation provides a new method to construct univalent harmonic mappings with the help of an improved distortion theorem.

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Sergey Yu. Graf, Saminathan Ponnusamy, Victor V. Starkov. 2015-10-16. Univalence criterion for harmonic mappings and $\Phi$-like functions. https://arxiv.org/abs/1510.04886

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