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arXiv · 1906.06258

Models of Hyperelliptic Curves with Tame Potentially Semistable Reduction

Omri Faraggi·Sarah Nowell
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Abstract

Let $C$ be a hyperelliptic curve $y^2 = f(x)$ over a discretely valued field $K$. The $p$-adic distances between the roots of $f(x)$ can be described by a completely combinatorial object known as the cluster picture. We show that the cluster picture of $C$, along with the leading coefficient of $f$ and the action of $\mathrm{Gal}(\bar{K}/K)$ on the roots of $f$, completely determines the combinatorics of the special fibre of the minimal strict normal crossings model of $C$. In particular, we give an explicit description of the special fibre in terms of this data.

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Omri Faraggi, Sarah Nowell. 2019-06-14. Models of Hyperelliptic Curves with Tame Potentially Semistable Reduction. https://doi.org/10.1112/tlm3.12023

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