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arXiv · 2111.03787

K3 Surfaces, Picard Numbers and Siegel Disks

Katsunori Iwasaki·Yuta Takada
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Abstract

If a K3 surface admits an automorphism with a Siegel disk, then its Picard number is an even integer between $0$ and $18$. Conversely, using the method of hypergeometric groups, we are able to construct K3 surface automorphisms with Siegel disks that realize all possible Picard numbers. The constructions involve extensive computer searches for appropriate Salem numbers and computations of algebraic numbers arising from holomorphic Lefschetz-type formulas and related Grothendieck residues.

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Katsunori Iwasaki, Yuta Takada. 2021-11-06. K3 Surfaces, Picard Numbers and Siegel Disks. https://arxiv.org/abs/2111.03787

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