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arXiv · 1707.08676

Hyperelliptic classes are rigid and extremal in genus two

Vance Blankers
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Abstract

We show that the class of the locus of hyperelliptic curves with $\ell$ marked Weierstrass points, $m$ marked conjugate pairs of points, and $n$ free marked points is rigid and extremal in the cone of effective codimension-($\ell + m$) classes on $\overline{\mathcal{M}}_{2,\ell+2m+n}$. This generalizes work of Chen and Tarasca and establishes an infinite family of rigid and extremal classes in arbitrarily-high codimension.

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Vance Blankers. 2017-07-27. Hyperelliptic classes are rigid and extremal in genus two. https://doi.org/10.46298/epiga.2020.volume4.4902

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