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arXiv · 2211.13598

A survey on abelian dynamical Galois groups

A. Ferraguti
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Abstract

Let $K$ be a number field, $f\in K[x]$ and $α\in K$. A recent conjecture of Andrews and Petsche predicts that the dynamical Galois group of the pair $(f,α)$ is abelian if and only if the pair $(f,α)$ is $K^{\text{ab}}$-conjugated to $(g,β)$, where $g$ is a power or a Chebyshev map and $β$ is $ζ$ or $ζ+ζ^{-1}$, respectively, and $ζ$ is a root of unity. We review three completely different approaches that allow to prove several cases of the conjecture.

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A. Ferraguti. 2022-11-24. A survey on abelian dynamical Galois groups. https://arxiv.org/abs/2211.13598

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