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arXiv · 1606.03853

New cubic fourfolds with odd degree unirational parametrizations

Kuan-Wen Lai
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Abstract

We prove that the moduli space of cubic fourfolds $\mathcal{C}$ contains a divisor $\mathcal{C}_{42}$ whose general member has a unirational parametrization of degree 13. This result follows from a thorough study of the Hilbert scheme of rational scrolls and an explicit construction of examples. We also show that $\mathcal{C}_{42}$ is uniruled.

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Kuan-Wen Lai. 2017-09-08. New cubic fourfolds with odd degree unirational parametrizations. https://doi.org/10.2140/ant.2017.11.1597

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