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arXiv · 1711.09225

Ordinary K3 surfaces over a finite field

Lenny Taelman
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Abstract

We give a description of the category of ordinary K3 surfaces over a finite field in terms of linear algebra data over Z. This gives an analogue for K3 surfaces of Deligne's description of the category of ordinary abelian varieties over a finite field, and refines earlier work by N.O. Nygaard and J.-D. Yu. Our main result is conditional on a conjecture on potential semi-stable reduction of K3 surfaces over p-adic fields. We give unconditional versions for K3 surfaces of large Picard rank and for K3 surfaces of small degree.

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Lenny Taelman. 2017-11-25. Ordinary K3 surfaces over a finite field. https://arxiv.org/abs/1711.09225

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