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arXiv · 2002.12403

Extremality of Rational Tails Boundary Strata in $\overline{\mathcal{M}}_{g,n}$

Vance Blankers
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Abstract

We review and develop some techniques used to investigate the effective cones of higher codimension classes. Our results show that a large collection of boundary strata of rational tails type are extremal in their effective cones on $\overline{\mathcal{M}}_{g,n}$ and provide evidence for the conjecture that all boundary strata of $\overline{\mathcal{M}}_{g,n}$ are extremal. As a corollary, we show that all boundary strata are extremal in genus zero.

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Vance Blankers. 2020-02-27. Extremality of Rational Tails Boundary Strata in $\overline{\mathcal{M}}_{g,n}$. https://arxiv.org/abs/2002.12403

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