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A dendrological proof of the Scott conjecture for automorphisms of free groups

Published online by Cambridge University Press:  20 January 2009

D. Gaboriau
Affiliation:
Umpa, CNRS UMR 128, Ens Lyon, 69364 Lyon Cedex 07, France E-mail: [email protected]
G. Levitt
Affiliation:
Laboratoire Émile Picard, CNRS UMR 5580, Université Paul Sabatier, 31062 Toulouse Cedex 4, France E-mail: [email protected]
M. Lustig
Affiliation:
Mathematik, Ruhr-Universität Bochum, 44780 Bochum, Germany E-mail: [email protected]
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Abstract

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Let α be an automorphism of a free group of rank n. The Scott conjecture, proved by Bestvina-Handel, asserts that the fixed subgroup of α has rank at most n. We give a short alternative proof of this result using R-trees.

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1998

References

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