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arXiv · 1310.0227

Maximal families of nodal varieties with defect

Remke Kloosterman
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Abstract

In this paper we prove that a nodal hypersurface in P^4 with defect has at least (d-1)^2 nodes, and if it has at most 2(d-2)(d-1) nodes and d>6 then it contains either a plane or a quadric surface. Furthermore, we prove that a nodal double cover of P^3 ramified along a surface of degree 2d with defect has at least d(2d-1) nodes. We construct the largest dimensional family of nodal degree d hypersurfaces in P^(2n+2) with defect for d sufficiently large.

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Remke Kloosterman. 2013-10-01. Maximal families of nodal varieties with defect. https://doi.org/10.1007/s00209-021-02814-7

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