English

Constructions of Kummer structures on generalized Kummer surfaces

Algebraic Geometry 2023-03-15 v3

Abstract

We study generalized Kummer surfaces Km3(A)_{3}(A), by which we mean the K3 surfaces obtained by desingularization of the quotient of an abelian surface AA by an order 33 symplectic automorphism group. Such a surface carries 99 disjoint configurations of two smooth rational curves C,CC,C' with CC=1CC'=1. This 9A29{\bf A}_{2}-configuration plays a role similar to the Nikulin configuration of 1616 disjoint smooth rational curves on (classical) Kummer surfaces. We study the (generalized) question of T. Shioda: suppose that Km3(A)_{3}(A) is isomorphic to Km3(B)_{3}(B), does that imply that AA and BB are isomorphic? We answer by the negative in general, by two methods: by a link between that problem and Fourier-Mukai partners of AA, and by construction of 9A29{\bf A}_{2}-configurations on Km3(A)_{3}(A) which cannot be exchanged under the automorphism group.

Keywords

Cite

@article{arxiv.2109.02146,
  title  = {Constructions of Kummer structures on generalized Kummer surfaces},
  author = {Xavier Roulleau and Alessandra Sarti},
  journal= {arXiv preprint arXiv:2109.02146},
  year   = {2023}
}

Comments

27 pages ; version with more details and clarity in the proofs of the results

R2 v1 2026-06-24T05:41:54.166Z