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arXiv · 0804.3286

A characterization of double covers of curves in terms of the ample cone of second symmetric product

Kungho Chan
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Abstract

We investigate the nef cone spanned by the diagonal and the fibre classes of second symmetric product of a curve of genus $g$. This 2-dimensional nef cone gives a characterization of double covers of curves of genus $\le \frac{g-1}{8}$. This is a generalization of a result by Debarre.

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Kungho Chan. 2008-05-08. A characterization of double covers of curves in terms of the ample cone of second symmetric product. https://arxiv.org/abs/0804.3286

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