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arXiv · 2001.08287

Wild Galois representations: a family of hyperelliptic curves with large inertia image

Nirvana Coppola
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Abstract

In this work we generalise the main result of arXiv:1812.05651 to the family of hyperelliptic curves with potentially good reduction over a $p$-adic field which have degree $p$ and the largest possible image of inertia under the $\ell$-adic Galois representation associated to its Jacobian. We will prove that this Galois representation factors as the tensor product of an unramified character and an irreducible representation of a finite group, which can be either equal to the inertia image (in which case the representation is easily determined) or a $C_2$-extension of it. In this second case, there are two suitable representations and we will describe the Galois action explicitly in order to determine the correct one.

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Nirvana Coppola. 2020-01-22. Wild Galois representations: a family of hyperelliptic curves with large inertia image. https://arxiv.org/abs/2001.08287

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