Exploració per autor "Ventura Capell, Enric"
Ara es mostren els items 62-72 de 72
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Relative order and spectrum in free and related groups
Delgado Rodríguez, Jordi; Ventura Capell, Enric; Zakharov, Alexander (2022-12-19)
Article
Accés obertWe consider a natural generalization of the concept of order of an element in a group: an element g ¿ G is said to have order k in a subgroup H (resp., in a coset Hu) of a group G if k is the first strictly positive integer ... -
Stallings automata and applications : BGSMath graduate course
Delgado Rodríguez, Jordi; Ventura Capell, Enric; Weil, Pascal (2023-02-15)
Report de recerca
Accés obertThe theory of Stallings automata provides a neat geometric representation of subgroups of the free group, and constitutes the modern —and probably the most natural and fruitful — approach to their study. Moreover, if the ... -
Stallings automata for free-times-abelian groups: intersections and index
Delgado Pin, Jordi; Ventura Capell, Enric (2022-06-22)
Article
Accés obertWe extend the classical Stallings theory (describing subgroups of free groups as automata) to direct products of free and abelian groups: after introducing enriched automata (i.e., automata with extra abelian labels), we ... -
Statistical properties of subgroups of free groups
Bassino, Frederique; Martino, Armando; Nicaud, Cyril; Ventura Capell, Enric; Weil, Pascal (2013-02-04)
Article
Accés obertThe usual way to investigate the statistical properties of finitely generated subgroups of free groups, and of finite presentations of groups, is based on the so-called word-based distribution: subgroups are generated ... -
The automorphism group of a free-by-cyclic group in rank 2
Bogopolski, Oleg; Martino, Armando; Ventura Capell, Enric (2007-05)
Article
Accés obertLet ¡ be an automorphism of a free group F 2 of rank 2 and let M ¡ = F 2 o ¡ Z be the corresponding mapping torus of ¡ . We prove that the group Out ( M ¡ ) is usually virtually cyclic. More- over, ... -
The conjugacy problem for free-by-cyclic groups
Martino, Armando; Ventura Capell, Enric (2004-04)
Report de recerca
Accés obertWe show that the conjugacy problem is solvable in [finitely generated free]-by-cyclic groups, by using a result of O. Maslakova that one can algorithmically find generating sets for the fixed sub- groups of free group ... -
The conjugacy problem in automaton groups is not solvable
Šunic, Z.; Ventura Capell, Enric (2012-08-15)
Article
Accés obert(Free abelian)-by-free, self-similar groups generated by finite self-similar sets of tree automorphisms and having unsolvable conjugacy problem are constructed. Along the way, finitely generated, orbit undecidable, free ... -
The conjugacy problem in extensions of Thompson's group F
Burillo Puig, José; Matucci, Francesco; Ventura Capell, Enric (2016-10-01)
Article
Accés obertWe solve the twisted conjugacy problem on Thompson’s group F. We also exhibit orbit undecidable subgroups of Aut(F), and give a proof that Aut(F) and Aut+(F) are orbit decidable provided a certain conjecture on Thompson’s ... -
TOPOLOGIA
Ventura Capell, Enric (Universitat Politècnica de Catalunya, 2024-04-04)
Examen
Accés restringit a la comunitat UPC -
Twisted conjugacy in braid groups
Gonzalez Meneses, Juan; Ventura Capell, Enric (2014-01-01)
Article
Accés obertIn this note we solve the twisted conjugacy problem for braid groups, i.e., we propose an algorithm which, given two braids u,v is an element of B-n and an automorphism phi is an element of Aut(B-n), decides whether v = ... -
Twisted conjugacy problem for endomorphisms of metabelian groups
Ventura Capell, Enric; Romankov, Vitali (Springer, 2009-03-01)
Article
Accés restringit per política de l'editorialLet M be a finitely generated metabelian group explicitly presented in a variety A2 of all metabelian groups. An algorithm is constructed which, for every endomorphism ϕ ∈ End(M) identical modulo an Abelian normal subgroup ...