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arXiv · 2401.05228

Local heights on hyperelliptic curves and quadratic Chabauty

L. Alexander Betts·Juanita Duque-Rosero·Sachi Hashimoto·Pim Spelier
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Abstract

Quadratic Chabauty is a $p$-adic method for determining rational points on curves. Local heights are arithmetic invariants used in the quadratic Chabauty method. We present an algorithm to compute these local heights for hyperelliptic curves at odd primes $\ell \neq p$. This algorithm significantly broadens the applicability of quadratic Chabauty to curves which were previously inaccessible due to the presence of non-trivial local heights. We provide numerous examples, including the first quadratic Chabauty computation for a curve having two primes with non-trivial local heights.

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L. Alexander Betts, Juanita Duque-Rosero, Sachi Hashimoto, Pim Spelier. 2024-01-10. Local heights on hyperelliptic curves and quadratic Chabauty. https://arxiv.org/abs/2401.05228

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