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arXiv · 1411.1703

Explicit surjectivity of Galois representations attached to abelian surfaces and $\operatorname{GL}_2$-varieties

Davide Lombardo
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Abstract

Let $A$ be an absolutely simple abelian variety without (potential) complex multiplication, defined over the number field $K$. Suppose that either $\dim A=2$ or $A$ is of $\operatorname{GL}_2$-type: we give an explicit bound $\ell_0(A,K)$ such that, for every prime $\ell>\ell_0(A,K)$, the image of the absolute Galois group of $K$ in $\operatorname{Aut}(T_\ell(A))$ is as large as it is allowed to be by endomorphisms and polarizations.

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Davide Lombardo. 2014-11-06. Explicit surjectivity of Galois representations attached to abelian surfaces and $\operatorname{GL}_2$-varieties. https://arxiv.org/abs/1411.1703

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