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arXiv · 1410.2673

Stability of hypersurface sections of quadric threefolds

Sangho Byun·Yongnam Lee
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Abstract

Let $S$ be a complete intersection of a smooth quadric 3-fold $Q$ and a hypersurface of degree $d$ in ${\mathbb P}^4$. In this paper we analyze GIT stability of $S$ with respect to the natural $G=SO(5, {\mathbb C})$-action. We prove that if $d\ge 4$ and $S$ has at worst semi-log canonical singularities then $S$ is $G$-stable. Also, we prove that if $d\ge 3$ and $S$ has at worst semi-log canonical singularities then $S$ is $G$-semistable.

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Sangho Byun, Yongnam Lee. 2014-10-10. Stability of hypersurface sections of quadric threefolds. https://doi.org/10.1007/s11425-014-4918-8

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