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arXiv · 2305.19030

Decomposable abelian $G$-curves and special subvarieties

Irene Spelta·Carolina Tamborini
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Abstract

We consider families of abelian Galois coverings of the line. When the Jacobian of the general element is totally decomposable, i.e., is isogenous to a product of elliptic curves, we prove that they yield special subvarieties of $\A_g$ if and only if a numerical condition holds, which in the general case is only known to be sufficient.

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Irene Spelta, Carolina Tamborini. 2023-05-30. Decomposable abelian $G$-curves and special subvarieties. https://arxiv.org/abs/2305.19030

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