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arXiv · 2109.07261

Shimura subvarieties via endomorphisms

Irene Spelta
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Abstract

We show the existence of two new Shimura subvarieties of $\mathcal{A}_2, \mathcal{A}_3$ generically contained in the Torelli locus. They provide the first examples of Shimura subvarieties obtained by means of Jacobians carrying non-trivial endomorphisms not directly induced by the automorphisms of the curves. We also obtain a new example of a Shimura subvariety of $\mathcal{A}_4$ generically contained in the Prym locus.

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Irene Spelta. 2021-09-15. Shimura subvarieties via endomorphisms. https://arxiv.org/abs/2109.07261

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