Abstract
New distortion theorems are proved for holomorphic univalent functions bounded in a circular annulus and preserving one of its boundary components. In particular, inequalities including the Schwarzian derivative at a boundary point of the annulus are established. All results follow from the properties of the conformal capacity of condensers and symmetrization.
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Funding
This research was supported by the Mathematical Center in Akademgorodok under agreement no. 075-15-2022-281 of 05.04.2022 with the Ministry of Science and Higher Education of the Russian Federation.
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Translated from Matematicheskie Zametki, 2023, Vol. 113, pp. 827–835 https://doi.org/10.4213/mzm13808.
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Dubinin, V.N. Boundary Distortion and the Schwarzian Derivative of a Univalent Function in a Circular Annulus. Math Notes 113, 776–783 (2023). https://doi.org/10.1134/S000143462305019X
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DOI: https://doi.org/10.1134/S000143462305019X