A nonspecial divisor in the moduli space of cubic fourfolds via 10-nodal plane sextics

Elena Sammarco

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arXiv · 2505.13187

A nonspecial divisor in the moduli space of cubic fourfolds via 10-nodal plane sextics

Elena Sammarco

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Abstract

In the moduli space $\mathcal{C}$ of complex cubic hypersurfaces $X\subset\mathbb{P}^5$, we study the condition that $X$ admits a net of polar quadrics whose discriminant locus is a $10$-nodal irreducible plane sextic curve. Our main result is that such a condition defines an irreducible divisor in $\mathcal{C}$ which is not of Noether-Lefschetz type.

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Elena Sammarco. 2025-05-19. A nonspecial divisor in the moduli space of cubic fourfolds via 10-nodal plane sextics. https://arxiv.org/abs/2505.13187

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