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arXiv · 2503.16201

A simple criterion for the uniruledness of an orthogonal modular variety

Ignacio Barros
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Abstract

We exhibit a simple uniruledness criterion for general orthogonal modular varieties in terms of invariants of the corresponding lattice. As an application, we obtain the uniruledness of almost all Nikulin--Vinberg moduli spaces parameterizing projective K3 surfaces of Picard number at least 3 and fixed finite automorphism group.

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Ignacio Barros. 2025-03-20. A simple criterion for the uniruledness of an orthogonal modular variety. https://arxiv.org/abs/2503.16201

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