The braided Ptolemy-Thompson group is finitely presented

Abstract

Pursueing our investigations on the relations between Thompson groups and mapping class groups, we introduce the group $T^{\ast }$ (and its further generalizations) which is an extension of the Ptolemy-Thompson group $T$ by means of the full braid group $B_{\infty }$ on infinitely many strands. We prove that it is a finitely presented group with solvable word problem, and give an explicit presentation of it.

35 p

Cited by in corpus (9)

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• An infinite genus mapping class group and stable cohomology
• Diffeomorphisms groups of tame Cantor sets and Thompson-like groups
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• Braided Thompson groups with and without quasimorphisms
• Braiding groups of automorphisms and almost-automorphisms of trees