Expanding Thurston maps as quotients

Daniel Meyer

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arXiv · 0910.2003

Expanding Thurston maps as quotients

Daniel Meyer

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Abstract

A Thurston map is a branched covering map $f\colon S^2\to S^2$ that is postcritically finite. Mating of polynomials, introduced by Douady and Hubbard, is a method to geometrically combine the Julia sets of two polynomials (and their dynamics) to form a rational map. We show that for every expanding Thurston map $f$ every sufficiently high iterate $F=f^n$ is obtained as the mating of two polynomials. One obtains a concise description of $F$ via critical portraits. The proof is based on the construction of the invariant Peano curve from Meyer. As another consequence we obtain a large number of fractal tilings of the plane and the hyperbolic plane.

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Daniel Meyer. 2012-10-22. Expanding Thurston maps as quotients. https://arxiv.org/abs/0910.2003

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