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arXiv · 1103.2893

Independence of $\ell$-adic Galois representations over function fields

Wojciech Gajda·Sebastian Petersen
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Abstract

Let $K$ be a finitely generated extension of $\mathbb{Q}$. We consider the family of $\ell$-adic representations ($\ell$ varies through the set of all prime numbers) of the absolute Galois group of $K$, attached to $\ell$-adic cohomology of a smooth separated scheme of finite type over $K$. We prove that the fields cut out from the algebraic closure of $K$ by the kernels of the representations of the family are linearly disjoint over a finite extension of K. This gives a positive answer to a question asked by Serre in 1991.

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Wojciech Gajda, Sebastian Petersen. 2012-01-11. Independence of $\ell$-adic Galois representations over function fields. https://arxiv.org/abs/1103.2893

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