Geometriae Dedicata

, Volume 89, Issue 1, pp 155–175 | Cite as

Rigidity of Branch Groups Acting on Rooted Trees

  • Yaroslav Lavreniuk
  • Volodymyr Nekrashevych


Automorphisms of groups acting faithfully on rooted trees are studied. We find conditions under which every automorphism of such a group is induced by a conjugation from the full automorphism group of the rooted tree. These results are applied to known examples such as Grigorchuk groups, Gupta–Sidki group, etc.

rooted trees group automorphisms automorphisms of rooted trees automata branch groups 


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Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • Yaroslav Lavreniuk
    • 1
  • Volodymyr Nekrashevych
    • 1
  1. 1.Faculty of Mechanics and MathematicsKyiv Taras Shevchenko UniversityKyivUkraine

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