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arXiv · 2604.20426

G-birationally rigid cubic threefolds

Ivan Cheltsov·Igor Krylov·Sione Ma'u
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Abstract

We classify pairs $(X,G)$ consisting of a (possibly singular) cubic threefold $X\subset\mathbb{P}^4$ and a finite subgroup $G\subset\mathrm{Aut}(X)$ such that $X$ is $G$-birationally rigid, i.e., $X$ is a $G$-Mori fiber space (over a point), and $X$ is not $G$-birational to any $G$-Mori fibre space that is not $G$-biregular to $X$.

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Ivan Cheltsov, Igor Krylov, Sione Ma'u. 2026-04-22. G-birationally rigid cubic threefolds. https://arxiv.org/abs/2604.20426

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