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arXiv · 2108.00900

Groups as automorphisms of dessins d'enfants

Alejandro Cañas·Ruben A. Hidalgo·Francisco Javier Turiel·Antonio Viruel
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Abstract

It is known that every finite group can be represented as the full group of automorphisms of a suitable compact dessin d'enfant. In this paper, we give a constructive and easy proof that the same holds for any countable group by considering non-compact dessins. Moreover, we show that any tame action of a countable group is so realizable.

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Alejandro Cañas, Ruben A. Hidalgo, Francisco Javier Turiel, Antonio Viruel. 2021-08-02. Groups as automorphisms of dessins d'enfants. https://arxiv.org/abs/2108.00900

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