Polygonal complexes and combinatorial group theory

  title={Polygonal complexes and combinatorial group theory},
  author={Werner Ballmann and M. Brin},
  journal={Geometriae Dedicata},
We study the structure of certain simply connected 2-dimensional complexes with non-positive curvature. We obtain a precise description of how these complexes behave at infinity and prove an existence theorem which gives an abundance of such complexes. We also investigate the structure of groups which act transitively on the set of vertices of such a complex. 
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