Abstract
We provide geometric estimates for conformal maps of the unit disc. As a consequence, a bound for the derivative of such maps follows yielding, in particular, an answer to a question posed by Martín Chuaqui. Finally, estimates regarding the curvature of image arcs under conformal maps are also obtained.
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The authors would like to thank the referee for a careful reading of the manuscript.
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E. A. Gallardo-Gutiérrez is partially supported by Plan Nacional I+D Grants No. MTM2016-77710-P and PID2019-105979GB-I00, Spain, Grupo UCM 910346, the Spanish Ministry of Science and Innovation, through the “Severo Ochoa Programme for Centres of Excellence in R&D” (SEV-2015-0554) and from the Spanish National Research Council, through the “Ayuda extraordinaria a Centros de Excelencia Severo Ochoa” (20205CEX001)
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Gallardo-Gutiérrez, E.A., Pommerenke, C. On geometric estimates for univalent functions. Annali di Matematica 200, 1075–1084 (2021). https://doi.org/10.1007/s10231-020-01026-w
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DOI: https://doi.org/10.1007/s10231-020-01026-w