Dynamics of Free Group Automorphisms

  • Peter Brinkmann
Part of the Trends in Mathematics book series (TM)


We present a coarse convexity result for the dynamics of free group automorphisms: Given an automorphism ø of a finitely generated free group F, we show that for all xF and 0 ≤ iN, the length of ø i (x) is bounded above by a constant multiple of the sum of the lengths of x and ø N (x), with the constant depending only on ø.

Mathematics Subject Classification (2000)



Free group automorphisms train tracks 


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Copyright information

© Springer Basel AG 2010

Authors and Affiliations

  • Peter Brinkmann
    • 1
  1. 1.Department of MathematicsThe City College of CUNYNew YorkUSA

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