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arXiv · 2108.07065

On the cuspidal locus in the dual varieties of Segre quartic surface

Nobuhiro Honda·Ayato Minagawa
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Abstract

Motivated by a kind of Penrose correspondence, we investigate the space of hyperplane sections of Segre quartic surfaces which have an ordinary cusp. We show that the space of such hyperplane sections is empty for two kinds of Segre surfaces, and it is a connected surface for all other kinds of Segre surfaces. We also show that when it is non-empty, the closure of the space is either birational to the surface itself or birational to a double covering of the surface, whose branch divisor consists of some specific lines on the surface.

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Nobuhiro Honda, Ayato Minagawa. 2021-08-16. On the cuspidal locus in the dual varieties of Segre quartic surface. https://arxiv.org/abs/2108.07065

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