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arXiv · 1407.5802

Galois representations and Galois groups over Q

Sara Arias-de-Reyna·Cécile Armana·Valentijn Karemaker·Marusia Rebolledo·Lara Thomas·Núria Vila
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Abstract

In this paper we generalize results of P. Le Duff to genus n hyperelliptic curves. More precisely, let C/Q be a hyperelliptic genus n curve and let J(C) be the associated Jacobian variety. Assume that there exists a prime p such that J(C) has semistable reduction with toric dimension 1 at p. We provide an algorithm to compute a list of primes l (if they exist) such that the Galois representation attached to the l-torsion of J(C) is surjective onto the group GSp(2n, l). In particular we realize GSp(6, l) as a Galois group over Q for all primes l in [11, 500000].

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Sara Arias-de-Reyna, Cécile Armana, Valentijn Karemaker, Marusia Rebolledo, Lara Thomas, Núria Vila. 2014-07-22. Galois representations and Galois groups over Q. https://arxiv.org/abs/1407.5802

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