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arXiv · 2511.15933

Jordan bounds for volume-preserving Cremona groups

Jiahe Wang
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Abstract

We show that the Jordan constant for the volume-preserving plane Cremona group $\mathrm{Bir}(\mathbb P^2, \Delta)$ is $12$. We provide a Jordan bound of $144$ for the three-dimensional volume-preserving Cremona group $\mathrm{Bir}(\mathbb P^3,\Delta)$. We also provide a weak geometric Jordan bound of $2^{11} \cdot 3^2$ for $\mathrm{Bir}(\mathbb P^2)$.

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Jiahe Wang. 2025-11-19. Jordan bounds for volume-preserving Cremona groups. https://arxiv.org/abs/2511.15933

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