The braided Ptolemy–Thompson group is asynchronously combable

  • Louis Funar

    Université Grenoble I, Saint-Martin-d'Hères, France
  • Christophe Kapoudjian

    Université Paul Sabatier – Toulouse 3, France
The braided Ptolemy–Thompson group is asynchronously combable cover
Download PDF

A subscription is required to access this article.

Abstract

The braided Ptolemy–Thompson group is an extension of the Thompson group by the full braid group on infinitely many strands and both of them can be viewed as mapping class groups of certain infinite planar surfaces. The main result of this article is that (and in particular ) is asynchronously combable. The result is new already for the group . The method of proof is inspired by Lee Mosher’s proof of automaticity of mapping class groups.

Cite this article

Louis Funar, Christophe Kapoudjian, The braided Ptolemy–Thompson group is asynchronously combable. Comment. Math. Helv. 86 (2011), no. 3, pp. 707–768

DOI 10.4171/CMH/239