1 4 N ov 2 00 8 Scott and Swarup ’ s regular neighbourhood as a tree of cylinders

نویسندگان

  • Vincent Guirardel
  • Gilbert Levitt
چکیده

Let G be a finitely presented group. Scott and Swarup have constructed a canonical splitting of G which encloses all almost invariant sets over virtually polycyclic subgroups of a given length. We give an alternative construction of this regular neighbourhood, by showing that it is the tree of cylinders of a JSJ splitting.

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تاریخ انتشار 2008