Infinitely wildly ramified arboreal representations for postcritically finite polynomials with potential good reduction

Alex Feiner

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arXiv · 2310.09372

Infinitely wildly ramified arboreal representations for postcritically finite polynomials with potential good reduction

Alex Feiner

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Abstract

Let $K$ be a number field, let $v$ be a finite place of $K$, let $f\in K[z]$ be a degree $d\geqslant2$ polynomial with $v|d$, and let $a\in K$. We show that if $f$ is postcritically bounded and has potential good reduction with respect to $v$, then the arboreal representation associated to the pair $(f,a)$ is either finite or infinitely wildly ramified above $v$.

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Alex Feiner. 2023-10-13. Infinitely wildly ramified arboreal representations for postcritically finite polynomials with potential good reduction. https://arxiv.org/abs/2310.09372

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