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arXiv · 1104.3788

On extensions of the Torelli map

Angela Gibney
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Abstract

The divisors on $\bar{\operatorname{M}}_g$ that arise as the pullbacks of ample divisors along any extension of the Torelli map to any toroidal compactification of $\operatorname{A}_g$ form a 2-dimensional extremal face of the nef cone of $\bar{\operatorname{M}}_g$, which is explicitly described.

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Angela Gibney. 2011-04-19. On extensions of the Torelli map. https://arxiv.org/abs/1104.3788

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