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arXiv · 1604.05954

An exceptional locus in the perfect compactification of $A_g$

N. Shepherd-Barron
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Abstract

The line bundle $12M-D$ on the perfect compactification $A_g^P$ is nef; we show here that in positive characteristic it is semi-ample and that in all characteristics its exceptional locus is the closure of the locus of abelian varieties with an elliptic factor.

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N. Shepherd-Barron. 2016-04-20. An exceptional locus in the perfect compactification of $A_g$. https://arxiv.org/abs/1604.05954

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