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arXiv · 2111.02920

Examples of non--effective rays at the boundary of the Mori cone of blow--ups of the plane

Ciro Ciliberto·Rick Miranda
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Abstract

In this paper we prove that no multiple of the linear system of plane curves of degree $d\geq 4$ with a point of multiplicity $d-m$ (with $2 \leq m \leq d$) and $m(2d-m)$ simple general points is effective.

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Ciro Ciliberto, Rick Miranda. 2021-11-04. Examples of non--effective rays at the boundary of the Mori cone of blow--ups of the plane. https://arxiv.org/abs/2111.02920

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