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arXiv · 2205.06751

On the size and local equations of fibres of general projections

Ziv Ran
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Abstract

For a general birational projection of a smooth nondegenerate projective $n$-fold from $\mathbb P^{n+c}$ to $\mathbb P^m$, $n<m\leq(n+c)/2$, all fibres have total length asymptotically bounded by $2^{\sqrt{n}+1} $ and the fibres are locally defined by linear and quadratic equations.

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Ziv Ran. 2022-05-13. On the size and local equations of fibres of general projections. https://doi.org/10.1016/j.aim.2022.108206

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