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arXiv · 2608.08909

The universal cover of the second-type locus of a cubic

Frank Gounelas
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Abstract

We prove that the surface of second-type lines on a general cubic fourfold has fundamental group of order two. Its universal cover, constructed by Huybrechts, is obtained by considering the two ramification points of the Gauss map along each second-type line.

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Frank Gounelas. 2026-08-09. The universal cover of the second-type locus of a cubic. https://arxiv.org/abs/2608.08909

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