Finite Groups of Symplectic Automorphisms of Supersingular K3 surfaces in Odd Characteristics

Bin Wang; Zhiwei Zheng

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arXiv · 2406.14499

Finite Groups of Symplectic Automorphisms of Supersingular K3 surfaces in Odd Characteristics

Bin Wang·Zhiwei Zheng

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Abstract

In 2009, Dolgachev-Keum showed that finite groups of tame symplectic automorphisms of K3 surfaces in positive characteristics are subgroups of the Mathieu group of degree 23. In this paper, we utilize lattice-theoretic methods to investigate symplectic actions of finite groups G on K3 surfaces in odd characteristics. For supersingular K3 surfaces with Artin invariants at least two, we develop a new machinery called p-root pairs to constrain possible symplectic finite group actions (without the assumption of tameness). The concept of p-root pair is closely related to root systems and Weyl groups. In particular, we provide alternative proof for many results by Dolgachev-Keum and give an upper bound for the exponent of p in |G|.

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BibTeX RIS

Bin Wang, Zhiwei Zheng. 2024-06-20. Finite Groups of Symplectic Automorphisms of Supersingular K3 surfaces in Odd Characteristics. https://arxiv.org/abs/2406.14499

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