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arXiv · 1609.02348

Automorphisms of Salem degree 22 on supersingular K3 surfaces of higher Artin invariant

Simon Brandhorst
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Abstract

We give a short proof that every supersingular K3 surface (except possibly in characteristic $2$ with Artin invariant $σ=10$) has an automorphism of Salem degree 22. In particular an infinite subgroup of the automorphism group does not lift to characteristic zero. The proof relies on the case $σ=1$ and the cone conjecture for K3 surfaces.

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Simon Brandhorst. 2020-10-07. Automorphisms of Salem degree 22 on supersingular K3 surfaces of higher Artin invariant. https://doi.org/10.4310/mrl.2018.v25.n4.a4

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