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arXiv · 1305.1265

Moriwaki divisors and the augmented base loci of divisors on the moduli space of curves

Salvatore Cacciola·Angelo Felice Lopez·Filippo Viviani
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Abstract

We study the cone of Moriwaki divisors on \bar{M}_g by means of augmented base loci. Using a result of Moriwaki, we prove that an R-divisor D satisfies the strict Moriwaki inequalities if and only if the augmented base locus of D is contained in the boundary of \bar{M}_g. Then we draw some interesting consequences on the Zariski decomposition of divisors on \bar{M}_g, on the minimal model program of \bar{M}_g and on the log canonical models \bar{M}_g(\alpha).

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Salvatore Cacciola, Angelo Felice Lopez, Filippo Viviani. 2013-05-06. Moriwaki divisors and the augmented base loci of divisors on the moduli space of curves. https://arxiv.org/abs/1305.1265

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