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arXiv · 1009.4664

$sl_n$ level 1 conformal blocks divisors on $\bar{M}_{0,n}$

Maxim Arap·Angela Gibney·James Stankewicz·David Swinarski
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Abstract

We study a family of semiample divisors on the moduli space $\bar{M}_{0,n}$ that come from the theory of conformal blocks for the Lie algebra $sl_n$ and level 1. The divisors we study are invariant under the action of $S_n$ on $\bar{M}_{0,n}$. We compute their classes and prove that they generate extremal rays in the cone of symmetric nef divisors on $\bar{M}_{0,n}$. In particular, these divisors define birational contractions of $\bar{M}_{0,n}$, which we show factor through reduction morphisms to moduli spaces of weighted pointed curves defined by Hassett.

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Maxim Arap, Angela Gibney, James Stankewicz, David Swinarski. 2010-09-23. $sl_n$ level 1 conformal blocks divisors on $\bar{M}_{0,n}$. https://arxiv.org/abs/1009.4664

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