English

On the commutator length of a Dehn twist

Geometric Topology 2010-10-25 v2

Abstract

We show that on a nonorientable surface of genus at least 7 any power of a Dehn twist is equal to a single commutator in the mapping class group and the same is true, under additional assumptions, for the twist subgroup, and also for the extended mapping class group of an orientable surface of genus at least 3.

Keywords

Cite

@article{arxiv.1007.0132,
  title  = {On the commutator length of a Dehn twist},
  author = {Blazej Szepietowski},
  journal= {arXiv preprint arXiv:1007.0132},
  year   = {2010}
}

Comments

Two references and one paragraph added acknowledging the fact that some results were known already. 6 pages