Rational cubic fourfolds with associated singular K3 surfaces

Hanine Awada

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arXiv · 2004.08446

Rational cubic fourfolds with associated singular K3 surfaces

Hanine Awada

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Abstract

Generalizing a recent construction of Yang and Yu, we study to what extent one can intersect Hassett's Noether-Lefschetz divisors $\mathcal{C}_d$ in the moduli space of cubic fourfolds $\mathcal{C}$. In particular, we exhibit arithmetic conditions on 20 indexes $d_1,\dots, d_{20}$ that assure that the divisors $\mathcal{C}_{d_1},\dots,\mathcal{C}_{d_{20}}$ all intersect one another. This allows us to produce examples of rational cubic fourfolds with an associated K3 surface with rank 20 N\'eron-Severi group, i.e. a singular K3 surface.

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Hanine Awada. 2020-04-17. Rational cubic fourfolds with associated singular K3 surfaces. https://arxiv.org/abs/2004.08446

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