Abstract
We give sharp estimates for distortion of harmonic mappings u from the unit disc \(\mathbb {U}\) into \(\mathbb {R}^{m}\), at a prescribed point by means of diameter and area of the corresponding surface \(S=u(\mathbb {U})\), and via the generalized length of the boundary of S.
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Notes
Using sticky-notes he wrote numerous comments on margins of the manuscript in which the corrections are elaborated.
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Acknowledgments
We wish to thank Shi Qingtian, who has been reading very carefully several versions of this manuscript, for useful discussions and useful comments. In particular, we are really grateful to an anonymous reviewer, who has put a lot of effort into examining closely the text,Footnote 1 for providing insightful comments and directions for improvement of the exposition.
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Mateljević, M. Schwarz Lemma, and Distortion for Harmonic Functions Via Length and Area. Potential Anal 53, 1165–1190 (2020). https://doi.org/10.1007/s11118-019-09802-x
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DOI: https://doi.org/10.1007/s11118-019-09802-x
Keywords
- Harmonic and holomorphic functions
- Hyperbolic distance
- Schwarz lemma
- Quasiconformal mappings
- Diametar
- Length
- Area