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arXiv · 1308.1267

Projective normality and the generation of the ideal of an Enriques surface

Andreas Leopold Knutsen·Angelo Felice Lopez
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Abstract

We give necessary and sufficient criteria for a smooth Enriques surface S in P^r to be scheme-theoretically an intersection of quadrics. Moreover we prove in many cases that, when S contains plane cubic curves, the intersection of the quadrics containing S is the union of S and the 2-planes spanned by the plane cubic curves. We also give a new (very quick) proof of the projective normality of S if the degree of S is at least 12.

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Andreas Leopold Knutsen, Angelo Felice Lopez. 2013-09-24. Projective normality and the generation of the ideal of an Enriques surface. https://arxiv.org/abs/1308.1267

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