English

Left-orderable groups that don't act on the line

Dynamical Systems 2014-10-16 v2 Group Theory

Abstract

We show that the group of germs at infinity of orientation-preserving homeomorphisms of R admits no action on the line. This gives an example of a left-orderable group of the same cardinality as Homeo+(R) that does not embed in Homeo+(R). As an application of our techniques, we construct a finitely generated group of germs that does not extend to Homeo+(R) and, separately, extend a theorem of E. Militon on homomorphisms between groups of homeomorphisms.

Cite

@article{arxiv.1406.5575,
  title  = {Left-orderable groups that don't act on the line},
  author = {Kathryn Mann},
  journal= {arXiv preprint arXiv:1406.5575},
  year   = {2014}
}

Comments

13 pages. V2 contains corrections and improvements to section 4

R2 v1 2026-06-22T04:43:52.061Z