JSJ-Decompositions of finitely presented groups and complexes of groups

  title={JSJ-Decompositions of finitely presented groups and complexes of groups},
  author={Koji Fujiwara and Panos Papasoglu},
  journal={Geometric \& Functional Analysis GAFA},
Abstract.A JSJ-splitting of a group G over a certain class of subgroups is a graph of groups decomposition of G which describes all possible decompositions of G as an amalgamated product or an HNN extension over subgroups lying in the given class. Such decompositions originated in 3-manifold topology. In this paper we generalize the JSJ-splitting constructions of Sela, Rips–Sela and Dunwoody–Sageev, and we construct a JSJ-splitting for any finitely presented group with respect to the class of… 
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