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Q-factorial quartic threefolds

Constantin Shramov
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Abstract

We prove that a nodal quartic threefold $X$ containing no planes is $Q$-factorial provided that it has not more than 12 singular points, with the exception of a quartic with exactly 12 singularities containing a quadric surface. We give some geometrical constructions related to the latter quartic.

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Constantin Shramov. 2008-03-30. Q-factorial quartic threefolds. https://arxiv.org/abs/math/0701459

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