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arXiv · 2109.07655

Normalization of congruence of bitangents to a hypersurface in $\mathbb P^3$

Hosung Kim·Yongnam Lee
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Abstract

A congruence is a surface in the Grassmannian ${\rm Gr}(2, 4)$. In this paper, we consider the normalization of congruence of bitangents to a hypersurface in $\mathbb P^3$. We call it the Fano congruence of bitangents. We give a criterion for smoothness of the Fano congruence of bitangents and describe explicitly their degenerations in a general Lefschetz pencil in the space of hypersurfaces in $\mathbb P^3$.

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Hosung Kim, Yongnam Lee. 2021-09-16. Normalization of congruence of bitangents to a hypersurface in $\mathbb P^3$. https://arxiv.org/abs/2109.07655

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