Orders of automorphisms of K3 surfaces

JongHae Keum

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arXiv · 1203.5616

Orders of automorphisms of K3 surfaces

JongHae Keum

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Abstract

We determine all posible orders of automorphisms of finite order of complex K3 surfaces or of K3 surfaces in characteristic $p>3$. E.g., a positive integer $N$ is the order of an automorphism of a complex K3 surface if and only if $ϕ(N)\le 20$ where $ϕ$ is the Euler function. In particular, 66 is the maximum finite order in each characteristic $p\neq 2,3$. As a consequence, we give a bound for the orders of finite groups acting on K3 surfaces in characteristic $p>7$.

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BibTeX RIS

JongHae Keum. 2013-09-22. Orders of automorphisms of K3 surfaces. https://arxiv.org/abs/1203.5616

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