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arXiv · 1811.10539

2-Selmer groups of even hyperelliptic curves over function fields

Dao Van Thinh
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Abstract

In this paper, we are going to compute the average size of 2-Selmer groups of families of even hyperelliptic curves over function fields. The result will be obtained by a geometric method which is based on a Vinberg representation of the group $G=\text{PSO}(2n+2)$ and a Hitchin fibration. Consistent with the result over Q of Arul Shankar and Xiaoheng Wang [Rational points on hyperelliptic curves having a marked non-Weierstrass point, in Compos. Math., 154(1):188-222, 2018], we provide an upper bound and a lower bound of the average. However, if we restrict to the family of transversal hyperelliptic curves, we obtain precisely number 6.

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Dao Van Thinh. 2018-11-26. 2-Selmer groups of even hyperelliptic curves over function fields. https://arxiv.org/abs/1811.10539

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