Groups of automorphisms of trees and their limit sets

  title={Groups of automorphisms of trees and their limit sets},
  author={Sa'ar Hersonsky and John H. Hubbard},
  journal={Ergodic Theory and Dynamical Systems},
Let T be a locally finite simplicial tree and let ! ⊂ Aut(T ) be a finitely generated discrete subgroup. We obtain an explicit formula for the critical exponent of the Poincare series associated with !, which is also the Hausdorff dimension of the limit set of !; this uses a description due to Lubotzky of an appropriate fundamental domain for finite index torsion-free subgroups of !. Coornaert, generalizing work of Sullivan, showed that the limit set is of finite positive measure in its… Expand

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