Geodesic currents and length compactness for automorphisms of free groups
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- by Stefano Francaviglia PDF
- Trans. Amer. Math. Soc. 361 (2009), 161-176 Request permission
Abstract:
We prove a compactness theorem for automorphisms of free groups. Namely, we show that the set of automorphisms keeping the length of the uniform current bounded is compact (up to conjugation). This implies that the spectrum of the length of the images of the uniform current is discrete, proving a conjecture of I. Kapovich.References
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Additional Information
- Stefano Francaviglia
- Affiliation: Departament de Matemàtiques, Edifici C, Universitat Autònoma, 08193 Bellaterra (Barcelona) Spain
- MR Author ID: 677681
- Email: s.francaviglia@sns.it
- Received by editor(s): May 22, 2006
- Received by editor(s) in revised form: October 25, 2006
- Published electronically: August 13, 2008
- Additional Notes: The author was supported by a Marie Curie Intra European Fellowship.
- © Copyright 2008
American Mathematical Society
The copyright for this article reverts to public domain 28 years after publication. - Journal: Trans. Amer. Math. Soc. 361 (2009), 161-176
- MSC (2000): Primary 20F65
- DOI: https://doi.org/10.1090/S0002-9947-08-04420-6
- MathSciNet review: 2439402