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arXiv · 0910.1212

Formal groups, supersingular abelian varieties and tame ramification

Sara Arias-de-Reyna
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Abstract

Let us consider an abelian variety defined over $\mathbb{Q_{\ell}}$ with good supersingular reduction. In this paper we give explicit conditions that ensure that the action of the wild inertia group on the $\ell$-torsion points of the variety is trivial. Furthermore we give a family of curves of genus 2 such that their Jacobian surfaces have good supersingular reduction and satisfy these conditions. We address this question by means of a detailed study of the formal group law attached to abelian varieties.

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Sara Arias-de-Reyna. 2009-10-07. Formal groups, supersingular abelian varieties and tame ramification. https://arxiv.org/abs/0910.1212

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