English

Toroidal 3-manifolds have circularly orderable fundamental groups

Geometric Topology 2026-07-12 v1

Abstract

In this article we prove that toroidal 3-manifolds have circularly-orderable fundamental groups by showing that they admit finite cyclic covers with left-orderable fundamental groups. These covers are also not L-spaces and often admit co-orientable taut foliations, as predicted by the L-space conjecture. As a consequence, we verify a conjecture of Ba and Clay, which characterises graph manifolds with circularly-orderable fundamental groups.

Cite

@article{arxiv.2607.10529,
  title  = {Toroidal 3-manifolds have circularly orderable fundamental groups},
  author = {Steven Boyer and Cameron McA. Gordon and Ying Hu},
  journal= {arXiv preprint arXiv:2607.10529},
  year   = {2026}
}

Comments

v1: 12 pages, no figures