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arXiv · 2209.03843

Jordan constant for Cremona group of rank 2 over a finite field

Anastasia V. Vikulova
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Abstract

In this paper we find the exact value of the Jordan constant for Cremona group of rank $2$ over all finite fields. During the proof we construct a cubic surface over $\mathbb{F}_2$ with a regular action of the group $\mathrm{S}_6$ which is the maximal automorphism group of cubic surfaces over $\mathbb{F}_2.$ Moreover, we prove the uniqueness up to isomorphism of such a cubic surface.

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Anastasia V. Vikulova. 2022-09-08. Jordan constant for Cremona group of rank 2 over a finite field. https://doi.org/10.1134/s0001434623030306

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