Limits of pluri-tangent planes to quartic surfaces

Ciro Ciliberto; Thomas Dedieu

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arXiv · 1304.7463

Limits of pluri-tangent planes to quartic surfaces

Ciro Ciliberto·Thomas Dedieu

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Abstract

We describe, for various degenerations $S\to \Delta$ of quartic $K3$ surfaces over the complex unit disk (e.g., to the union of four general planes, and to a general Kummer surface), the limits as $t\in \Delta^*$ tends to 0 of the Severi varieties $V_\delta(S_t)$, parametrizing irreducible $\delta$-nodal plane sections of $S_t$. We give applications of this to (i) the counting of plane nodal curves through base points in special position, (ii) the irreducibility of Severi varieties of a general quartic surface, and (iii) the monodromy of the universal family of rational curves on quartic $K3$ surfaces.

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BibTeX RIS

Ciro Ciliberto, Thomas Dedieu. 2013-04-28. Limits of pluri-tangent planes to quartic surfaces. https://arxiv.org/abs/1304.7463

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