no. 11
Group theory/Topology
Unbounded asymmetry of stretch factors
[Asymétrie non bornée des facteurs d'étirement]

Présenté par : the Editorial Board

Dowdall, Spencer1 ; Kapovich, Ilya1 ; Leininger, Christopher J.1
1 Department of Mathematics, University of Illinois at Urbana-Champaign, 1409 West Green Street, Urbana, IL 61801, United States
Comptes Rendus. Mathématique, Tome 352 (2014) no. 11, pp. 885-887.

Un énoncé de Handel–Mosher certifie que le rapport des logarithmes des facteurs d'étirement d'un automorphisme iréductible du groupe libre FN et de son inverse est borné par une constante CN. Nous montrons dans la présente courte note que cette constante CN ne peut pas être choisie indépendante de N.

A result of Handel–Mosher guarantees that the ratio of logarithms of stretch factors of any fully irreducible automorphism of the free group FN and its inverse is bounded by a constant CN. In this short note, we show that this constant CN cannot be chosen independent of the rank N.

Reçu le :
Accepté le :
Publié le :
DOI : 10.1016/j.crma.2014.09.007
Dowdall, Spencer 1 ; Kapovich, Ilya 1 ; Leininger, Christopher J. 1

1 Department of Mathematics, University of Illinois at Urbana-Champaign, 1409 West Green Street, Urbana, IL 61801, United States 
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Dowdall, Spencer; Kapovich, Ilya; Leininger, Christopher J. Unbounded asymmetry of stretch factors. Comptes Rendus. Mathématique, Tome 352 (2014) no. 11, pp. 885-887. doi : 10.1016/j.crma.2014.09.007. http://www.numdam.org/articles/10.1016/j.crma.2014.09.007/

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