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arXiv · 2410.14085

The 2-divisibility of divisors on K3 surfaces in characteristic 2

Toshiyuki Katsura·Shigeyuki Kondō·Matthias Schütt
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Abstract

We show that K3 surfaces in characteristic 2 can admit sets of $n$ disjoint smooth rational curves whose sum is divisible by 2 in the Picard group, for each $n=8,12,16,20$. More precisely, all values occur on supersingular K3 surfaces, with exceptions only at Artin invariants 1 and 10, while on K3 surfaces of finite height, only $n=8$ is possible.

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Toshiyuki Katsura, Shigeyuki Kondō, Matthias Schütt. 2024-10-17. The 2-divisibility of divisors on K3 surfaces in characteristic 2. https://arxiv.org/abs/2410.14085

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