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arXiv · 1503.01099

Singularities of secant varieties

Chih-Chi Chou·Lei Song
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Abstract

We study the singularities of the secant variety $\Sigma(X,L)$ associated to a smooth variety $X$ embedded by a sufficiently positive adjoint bundle $L$. We show that $\Sigma(X,L)$ is always Du Bois singular. Examples of secant varieties with worse singularities when $L$ has weak positivity are provided. We also give a necessary and sufficient condition for $\Sigma(X, L)$ to have rational singularities.

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Chih-Chi Chou, Lei Song. 2015-03-03. Singularities of secant varieties. https://arxiv.org/abs/1503.01099

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