English

Hyperbolicity for large automorphism groups of projective surfaces

Dynamical Systems 2023-10-03 v2 Algebraic Geometry

Abstract

We study the hyperbolicity properties of the action of a non-elementary automorphism group on a compact complex surface, with an emphasis on K3 and Enriques surfaces. A first result is that when such a group contains parabolic elements, Zariski diffuse invariant measures automatically have non-zero Lyapunov exponents. In combination with our previous work, this leads to simple criteria for a uniform expansion property on the whole surface, for groups with and without parabolic elements. This, in turn, has strong consequences on the dynamics: description of orbit closures, equidistribution, ergodicity properties, etc. Along the way, we provide a reference discussion on uniform expansion of non-linear discrete group actions on compact (real) manifolds and the construction of Margulis functions under optimal moment conditions.

Keywords

Cite

@article{arxiv.2211.02418,
  title  = {Hyperbolicity for large automorphism groups of projective surfaces},
  author = {Serge Cantat and Romain Dujardin},
  journal= {arXiv preprint arXiv:2211.02418},
  year   = {2023}
}
R2 v1 2026-06-28T05:11:10.944Z