On projective threefolds with two-dimensional space of vanishing cycles

Timofey Fedorov

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arXiv · 2501.13027

On projective threefolds with two-dimensional space of vanishing cycles

Timofey Fedorov

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Abstract

We obtain a complete list of smooth projective threefolds over $\mathbb C$ for which the dimension of the space of vanishing cycles (in $H^2$ of the smooth hyperplane section) equals $2$. We also obtain a complete list of rank 2 very ample vector bundles $E$ on smooth projective surfaces with $c_2(E) = 3$.

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Timofey Fedorov. 2025-01-22. On projective threefolds with two-dimensional space of vanishing cycles. https://arxiv.org/abs/2501.13027

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