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Dessins d'enfants and Hubbard Trees

Kevin Pilgrim
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Abstract

We show that the absolute Galois group acts faithfully on the set of Hubbard trees. Hubbard trees are finite planar trees, equipped with self-maps, which classify postcritically finite polynomials as holomorphic dynamical systems on the complex plane. We establish an explicit relationship between certain Hubbard trees and the trees known as ``dessins d'enfant'' introduced by Grothendieck.

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Kevin Pilgrim. 1999-05-26. Dessins d'enfants and Hubbard Trees. https://arxiv.org/abs/math/9905170

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