Un énoncé de Handel–Mosher certifie que le rapport des logarithmes des facteurs d'étirement d'un automorphisme iréductible du groupe libre et de son inverse est borné par une constante . Nous montrons dans la présente courte note que cette constante 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 and its inverse is bounded by a constant . In this short note, we show that this constant cannot be chosen independent of the rank N.
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Spencer Dowdall 1 ; Ilya Kapovich 1 ; Christopher J. Leininger 1
@article{CRMATH_2014__352_11_885_0, author = {Spencer Dowdall and Ilya Kapovich and Christopher J. Leininger}, title = {Unbounded asymmetry of stretch factors}, journal = {Comptes Rendus. Math\'ematique}, pages = {885--887}, publisher = {Elsevier}, volume = {352}, number = {11}, year = {2014}, doi = {10.1016/j.crma.2014.09.007}, language = {en}, }
Spencer Dowdall; Ilya Kapovich; Christopher J. Leininger. Unbounded asymmetry of stretch factors. Comptes Rendus. Mathématique, Volume 352 (2014) no. 11, pp. 885-887. doi : 10.1016/j.crma.2014.09.007. https://comptes-rendus.academie-sciences.fr/mathematique/articles/10.1016/j.crma.2014.09.007/
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