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arXiv · 2501.03483

A refined Chabauty--Coleman bound for surfaces

Jennifer S. Balakrishnan·Jerson Caro
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Abstract

Caro and Pasten gave an explicit upper bound on the number of rational points on a hyperbolic surface that is embedded in an abelian variety of rank at most one. We show how to use their method to produce a refined bound on the number of rational points on the surface $W_2 := C+C$ in the case of a hyperelliptic curve $C$ of genus $3$ over $\mathbb{Q}$. Combining this with work of Siksek, we use this to determine $W_2(\mathbb{Q})$ in a selection of examples.

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BibTeXRIS

Jennifer S. Balakrishnan, Jerson Caro. 2025-01-07. A refined Chabauty--Coleman bound for surfaces. https://arxiv.org/abs/2501.03483

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