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arXiv · 2508.11496

$\mathfrak A_5$-equivariant geometry of quadric threefolds

Antoine Pinardin·Zhijia Zhang
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Abstract

We classify $G$-Mori fibre spaces equivariantly birational to smooth quadric threefolds with fixed-point free actions of the alternating group $G=\mathfrak A_5$. We deduce that such quadric threefolds are $G$-solid and the $G$-actions on them are not projectively linearizable.

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Antoine Pinardin, Zhijia Zhang. 2025-08-15. $\mathfrak A_5$-equivariant geometry of quadric threefolds. https://arxiv.org/abs/2508.11496

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