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arXiv · 1407.5708

A lifting of an automorphism of a K3 surface over odd characteristic

Junmyeong Jang
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Abstract

In this paper, we prove that, over an algebraically closed field of odd characteristic, a weakly tame automorphism of a K3 surface of finite height can be lifted over the ring of Witt vectors of the base field. Also we prove that a non-symplectic tame automorphism of a supersingular K3 surface or a symplectic tame automorphism of a supersingular K3 surface of Artin-invariant at least 2 can be lifted over the ring of Witt vectors. Using these results, we prove, for a weakly tame K3 surface of finite height, there is a lifting over the ring of Witt vectors to which whole the automorphism group of the K3 surface can be lifted. Also we prove a K3 surface equipped with a purely non-symplectic automorphism of a certain order is unique up to isomorphism.

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Junmyeong Jang. 2014-07-22. A lifting of an automorphism of a K3 surface over odd characteristic. https://arxiv.org/abs/1407.5708

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