Linear systems associated to unicuspidal rational plane curves

Daniel Daigle; Alejandro Melle Hernández

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arXiv · 1202.6146

Linear systems associated to unicuspidal rational plane curves

Daniel Daigle·Alejandro Melle Hernández

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Abstract

A curve C in the projective plane is called non-negative if the self-intersection number of C after the minimal resolution of singularities of C is non-negative. Given a unicuspidal rational plane curve C with singular point P, we study the unique pencil Lambda_C on the projective plane satisfying C is in Lambda_C and P is its unique base point. We show that the general member of Lambda_C is a rational curve if and only if the curve C is non-negative. We also show that in such a case then Lambda_C has a dicritical of degree 1. Note that all currently known unicuspidal rational curves C in the projective plane are non-negative.

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BibTeX RIS

Daniel Daigle, Alejandro Melle Hernández. 2012-02-28. Linear systems associated to unicuspidal rational plane curves. https://arxiv.org/abs/1202.6146

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