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arXiv · 2201.05898

Conformal Rigidity of Polar Set Complements

Ratna Pal·Koushik Ramachandran·Sivaguru Ravisankar
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Abstract

Let $E$ be a closed polar subset of $\mathbb{C}$. In this short note, we use elementary potential theoretic tools to show that any conformal map on $\mathbb{C}\setminus{E}$ is necessarily a M\"{o}bius map. As a consequence we obtain that the group of conformal automorphisms of the complement of a closed polar set $E$ is a discrete subgroup of the M\"{o}bius group, provided $\lvert E \rvert \ge 2$.

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Ratna Pal, Koushik Ramachandran, Sivaguru Ravisankar. 2022-01-15. Conformal Rigidity of Polar Set Complements. https://arxiv.org/abs/2201.05898

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