English

Divergent geodesics in the Universal Teichm\"uller space

Complex Variables 2023-07-07 v1

Abstract

Thurston boundary of the universal Teichm\"uller space T(D)T(\mathbb{D}) is the space PMLbdd(D)PML_{bdd}(\mathbb{D}) of projective bounded measured laminations of D\mathbb{D}. A geodesic ray in T(D)T(\mathbb{D}) is of generalized Teichm\"uller type if it shrinks the vertical foliation of a holomorphic quadratic differential. We provide the first examples of generalized Teichm\"uller rays which diverge near Thurston boundary PLMbdd(D)PLM_{bdd}(\mathbb{D}). Moreover, for every k1k\geq 1 we construct examples of rays with limit sets homeomorphic to kk-dimensional cubes. For the latter result we utilize the classical Kronecker approximation theorem from number theory which states that if θ1,,θk\theta_1,\ldots,\theta_k are rationally independent reals then the sequence ({θ1n},,{θkn})(\{\theta_1 n\},\ldots,\{\theta_k n\}) is dense in the kk-torus Tk\mathbb{T}^k.

Keywords

Cite

@article{arxiv.2307.02775,
  title  = {Divergent geodesics in the Universal Teichm\"uller space},
  author = {Xinlong Dong and Hrant Hakobyan},
  journal= {arXiv preprint arXiv:2307.02775},
  year   = {2023}
}

Comments

32 pages, 5 figures

R2 v1 2026-06-28T11:23:22.845Z