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arXiv · 1807.05654

The spherical metric and univalent harmonic mappings

Yusuf Abu Muhanna·Rosihan M. Ali·Saminathan Ponnusamy
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Abstract

Let $f=h+\overline{g}$ be a harmonic univalent map in the unit disk $\mathbb{D}$, where $h $ and $g$ are analytic. We obtain an improved estimate for the second coefficient of $h$. This indeed is the first qualitative improvement after the appearance of the papers by Clunie and Sheil-Small in 1984, and by Sheil-Small in 1990. Also, when the sup-norm of the dilatation is less than $1$, it is shown that the spherical area of the covering surface of $h$ is dominated by the spherical area of the covering surface of $f.$

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Yusuf Abu Muhanna, Rosihan M. Ali, Saminathan Ponnusamy. 2018-07-16. The spherical metric and univalent harmonic mappings. https://doi.org/10.1007/s00605-018-1160-4

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