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Fubini's Theorem in codimension two

J. M. Landsberg·Colleen Robles
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Abstract

We classify codimension two analytic submanifolds X of projective space having the property that any line through a general point p having contact to order two with X at p automatically has contact to order three. We give applications to the study of the Debarre--de Jong conjecture, and of n-dimensional varieties whose Fano variety of lines has dimension 2n-4.

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J. M. Landsberg, Colleen Robles. 2005-09-09. Fubini's Theorem in codimension two. https://arxiv.org/abs/math/0509227

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