On démontre l'alternative suivante : ou bien il existe un groupe de type fini à croissance exponentielle et à entropie nulle, ou bien il existe une constante universelle M>0 qui minore les entropies de tous les groupes hyperboliques non élémentaires à centralisateurs cycliques et celle de leurs sous-groupes non élémentaires.
We prove the following alternative: either there exists a finitely generated group with exponential growth whose entropy is zero, or there exists a universal constant M>0 such that the entropy of all non-elementary hyperbolic groups with cyclic centralizers and their non-elementary subgroups is at least M.
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@article{CRMATH_2002__334_9_743_0, author = {Guirardel, Vincent}, title = {Une alternative sur l'entropie des groupes}, journal = {Comptes Rendus. Math\'ematique}, pages = {743--746}, publisher = {Elsevier}, volume = {334}, number = {9}, year = {2002}, doi = {10.1016/S1631-073X(02)02365-8}, language = {fr}, url = {http://www.numdam.org/articles/10.1016/S1631-073X(02)02365-8/} }
TY - JOUR AU - Guirardel, Vincent TI - Une alternative sur l'entropie des groupes JO - Comptes Rendus. Mathématique PY - 2002 SP - 743 EP - 746 VL - 334 IS - 9 PB - Elsevier UR - http://www.numdam.org/articles/10.1016/S1631-073X(02)02365-8/ DO - 10.1016/S1631-073X(02)02365-8 LA - fr ID - CRMATH_2002__334_9_743_0 ER -
Guirardel, Vincent. Une alternative sur l'entropie des groupes. Comptes Rendus. Mathématique, Tome 334 (2002) no. 9, pp. 743-746. doi : 10.1016/S1631-073X(02)02365-8. http://www.numdam.org/articles/10.1016/S1631-073X(02)02365-8/
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