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arXiv · 2608.04298

Prym--Tyurin varieties coming from intermediate coverings of curves

Víctor Valdebenito Sepúlveda
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Abstract

We introduce a new geometric construction of Prym--Tyurin varieties of odd prime exponent $p$ arising from intermediate coverings of $\mathbb Z_p\times\mathbb Z_p$--Galois covers of smooth curves. We determine precisely when these coverings give rise to Prym--Tyurin varieties, namely when the base curve is elliptic and in the case of isotropic étale covers over curves of genus $2$. The explicit nature of the construction makes it possible to analyze the geometry of the associated Prym--Tyurin varieties and to prove that the corresponding Prym--Tyurin maps, indexed by the choice of a generating vector, are generically finite onto their images.

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Víctor Valdebenito Sepúlveda. 2026-09-04. Prym--Tyurin varieties coming from intermediate coverings of curves. https://arxiv.org/abs/2608.04298

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