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arXiv · 2602.02314

The theorem of Maehara-Severi for maps of general type

Finn Bartsch·Ariyan Javanpeykar·Erwan Rousseau
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Abstract

We prove a finiteness result for dominant rational maps whose orbifold base is of general type. Our finiteness result generalizes Maehara's theorem that a given variety dominates only finitely many projective varieties of general type up to birational equivalence, and also answers a question of Campana on the finiteness of Bogomolov sheaves. We give several further applications, including finiteness results for maps to curves, abelian varieties, and K3 surfaces.

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Finn Bartsch, Ariyan Javanpeykar, Erwan Rousseau. 2026-02-02. The theorem of Maehara-Severi for maps of general type. https://arxiv.org/abs/2602.02314

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