On covering and quasi-unsplit families of rational curves

L. Bonavero; C. Casagrande; S. Druel

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On covering and quasi-unsplit families of rational curves

L. Bonavero·C. Casagrande·S. Druel

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Abstract

We study extremality properties of covering families of rational curves on projective varieties. Among others, we show that on a normal and Q-factorial projective variety of dimension at most 4, every covering and quasi-unsplit family of rational curves generates a geometric extremal ray of the Mori cone.

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L. Bonavero, C. Casagrande, S. Druel. 2005-04-04. On covering and quasi-unsplit families of rational curves. https://arxiv.org/abs/math/0504056

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