English

Counter-example to global Torelli problem for irreducible symplectic manifolds

Algebraic Geometry 2007-05-23 v3

Abstract

We shall give an example of irreducible symplectic manifolds X and Y which are not bimeromorphic, but have the same periods in the second cohomologies. More explicitly, X and Y are generalized Kummer varieties of dim 4 for a general complex torus T of dim 2 and its dual torus T^*. A key result is an observation of Shioda for the periods of T and T^*. As a concluding remark, we shall discuss the difference between our case and Kummer surfaces.

Keywords

Cite

@article{arxiv.math/0110114,
  title  = {Counter-example to global Torelli problem for irreducible symplectic manifolds},
  author = {Yoshinori Namikawa},
  journal= {arXiv preprint arXiv:math/0110114},
  year   = {2007}
}

Comments

The main part does not change. But Remark 3 is not correct (Erratum is added at the end of the paper)

R2 v1 2026-07-22T16:40:49.871Z