English

On links between horocyclic and geodesic orbits on geometrically infinite surfaces

Geometric Topology 2017-07-26 v1 Dynamical Systems

Abstract

We study the topological dynamics of the horocycle flow hRh_\mathbb{R} on a geometrically infinite hyperbolic surface S. Let u be a non-periodic vector for hRh_\mathbb{R} in T^1 S. Suppose that the half-geodesic u(R+)u(\mathbb{R}^+) is almost minimizing and that the injectivity radius along u(R+)u(\mathbb{R}^+) has a finite inferior limit Inj(u(R+))Inj(u(\mathbb{R}^+)). We prove that the closure of hRuh_\mathbb{R} u meets the geodesic orbit along un unbounded sequence of points gtnug_{t_n} u. Moreover, if Inj(u(R+))=0Inj(u(\mathbb{R}^+)) = 0, the whole half-orbit gR+ug_{\mathbb{R}^+} u is contained in hRuh_\mathbb{R} u. When Inj(u(R+))>0Inj(u(\mathbb{R}^+)) > 0, it is known that in general gR+uhRug_{\mathbb{R}^+} u \subset h_\mathbb{R} u. Yet, we give a construction where Inj(u(R+))>0Inj(u(\mathbb{R}^+)) > 0 and gR+uhRug_{\mathbb{R}^+} u \subset h_\mathbb{R} u, which also constitutes a counterexample to Proposition 3 of [Led97].

Keywords

Cite

@article{arxiv.1707.08022,
  title  = {On links between horocyclic and geodesic orbits on geometrically infinite surfaces},
  author = {Alexandre Bellis},
  journal= {arXiv preprint arXiv:1707.08022},
  year   = {2017}
}
R2 v1 2026-06-22T20:56:57.176Z