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arXiv · 2505.15717

On the fixed locus of the antisymplectic involution of an EPW cube

Francesca Rizzo
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Abstract

EPW cubes are polarized hyper-K\"ahler varieties of K$3^{[3]}$-type that carry an anti-symplectic involution. We study the geometry of the fixed locus $\sW_A$ of this involution and prove that it is a \emph{rigid} atomic Lagrangian submanifold. Our proof is based on a detailed description of certain singular degenerations of EPW cubes and the degeneration methods of Flappan--Macr\`i--O'Grady--Sacc\`a.

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Francesca Rizzo. 2025-05-21. On the fixed locus of the antisymplectic involution of an EPW cube. https://arxiv.org/abs/2505.15717

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