Groups with small Dehn functions and bipartite chord diagrams
Group Theory
2007-05-23 v3 Geometric Topology
Abstract
We introduce a new invariant of bipartite chord diagrams and use it to construct the first examples of groups with Dehn function and other small Dehn functions. Some of these groups have undecidable conjugacy problem.
Cite
@article{arxiv.math/0411174,
title = {Groups with small Dehn functions and bipartite chord diagrams},
author = {Alexander Olshanskii and Mark Sapir},
journal= {arXiv preprint arXiv:math/0411174},
year = {2007}
}
Comments
39 pages; We added a section where we prove that multiple HNN extensions of free groups having undecidable conjugacy problem cannot have Dehn functions smaller than n^2 log n; 9/14/05 - made changes suggested by the referee. The paper is accepted in GAFA