English

A geometric path from zero Lyapunov exponents to rotation cocycles

Dynamical Systems 2019-02-20 v6 Differential Geometry Metric Geometry

Abstract

We consider cocycles of isometries on spaces of nonpositive curvature HH. We show that the supremum of the drift over all invariant ergodic probability measures equals the infimum of the displacements of continuous sections under the cocycle dynamics. In particular, if a cocycle has uniform sublinear drift, then there are almost invariant sections, that is, sections that move arbitrarily little under the cocycle dynamics. If, in addition, HH is a symmetric space, then we show that almost invariant sections can be made invariant by perturbing the cocycle.

Keywords

Cite

@article{arxiv.1112.0397,
  title  = {A geometric path from zero Lyapunov exponents to rotation cocycles},
  author = {Jairo Bochi and Andrés Navas},
  journal= {arXiv preprint arXiv:1112.0397},
  year   = {2019}
}

Comments

To appear in Ergodic Theory and Dynamical Systems. The title was reverted to a previous one. Some modifications were made according to the referee's suggestions. We also included an alternative proof of Theorem A

R2 v1 2026-06-21T19:45:08.073Z