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arXiv · 2505.16497

K3 surfaces of degree six arising from desmic tetrahedra

Alex Degtyarev·Igor Dolgachev·Shigeyuki Kondo
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Abstract

We study K3 surfaces of degree 6 containing two sets of 12 skew lines such that each line from a set intersects exactly six lines from the other set. These surfaces arise as hyperplane sections of the cubic line complex associated with the pencil of desmic quartic surfaces introduced by George Humbert and recently studied by the second and third authors. We discuss alternative birational models of the surfaces, compute the Picard lattice and a group of projective automorphisms, and describe rational curves of low degree on the general surface.

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Alex Degtyarev, Igor Dolgachev, Shigeyuki Kondo. 2025-06-21. K3 surfaces of degree six arising from desmic tetrahedra. https://arxiv.org/abs/2505.16497

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