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arXiv · 0705.3912

Triple-Point Defective Regular Surfaces

Luca Chiantini·Thomas Markwig
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Abstract

In this paper we study the linear series |L-3p| of hyperplane sections with a triple point p of a surface S embedded via a very ample line bundle L for a general point p. If this linear series does not have the expected dimension we call (S,L) triple-point defective. We show that on a triple-point defective regular surface through a general point every hyperplane section has either a triple component or the surface is rationally ruled and the hyperplane section contains twice a fibre of the ruling.

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Luca Chiantini, Thomas Markwig. 2009-11-06. Triple-Point Defective Regular Surfaces. https://arxiv.org/abs/0705.3912

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