dc.creator | Fernández Lasheras, Francisco Jesús | es |
dc.creator | Mihalik, Michael | es |
dc.date.accessioned | 2023-12-18T12:55:54Z | |
dc.date.available | 2023-12-18T12:55:54Z | |
dc.date.issued | 2023-07-03 | |
dc.identifier.citation | Fernández Lasheras, F.J. y Mihalik, M. (2023). Lifting Semistability in Finitely Generated Ascending HNN-Extensions. Annales de l'Institut Fourier. | |
dc.identifier.issn | 1777-5310 | es |
dc.identifier.issn | 0373-0956 | es |
dc.identifier.uri | https://hdl.handle.net/11441/152636 | |
dc.description.abstract | If a finitely generated group G maps epimorphically onto a group
H, we are interested in the question: When does the semistability of H imply G is
semistable? In this paper, we give an answer within the class of ascending HNNextensions. More precisely, our main theorem states: Suppose that the 1-ended
finitely generated ascending HNN-extension H = ⟨S, t; R, t−1st = ϕ(s), s ∈ S⟩ is
semistable at infinity. Let R be the kernel of the obvious homomorphism from
the free group F({t} ∪ S) onto H, then there is a finite subset R0 ⊆ R such
that those finitely generated ascending HNN-extensions H1 = ⟨S, t; R1, t−1st =
ϕ(s), s ∈ S⟩, with R0 ⊆ R1 ⊂ R, are all 1-ended and semistable at infinity as
well. Furthermore H1 has such a presentation with R1 ⊂ R. Note that there is an
obvious epimorphism from H1 to H. It is unknown whether all finitely presented
ascending HNN-extensions are semistable at infinity. | es |
dc.description.abstract | La question fondamentale de cet article est de savoir sous quelles
conditions la semistabilité d’un groupe H entraîne la semistabilité d’un groupe G
qui admet une surjection sur H. Nous allons y répondre dans le cadre des extensions
HNN ascendantes. Plus précisement, considérons une extension HNN de type fini
ayant un seul bout H = ⟨S, t; R, t−1st = ϕ(s), s ∈ S⟩ qu’on suppose être semistable
à l’infini. Soit R le noyau du morphisme tautologique du groupe libre F({t} ∪ S)
sur H. Alors il existe un sous-ensemble fini R0 ⊆ R tel que toute extension HNN
de type fini H1 = ⟨S, t; R1, t−1st = ϕ(s), s ∈ S⟩, ayant R0 ⊆ R1 ⊂ R, n’a qu’un
seul bout et est semistable à l’infini. De plus H1 admet une telle présentation avec
R1 ⊂ R. Notons qu’il y a un épimorphisme de H1 dans H. A l’heure actuelle, nous
ne savons pas si toutes les extensions HNN ascendantes sont semistables à l’infini. | es |
dc.format | application/pdf | es |
dc.format.extent | 17 p. | es |
dc.language.iso | eng | es |
dc.publisher | Association des Annales de l'Institut Fourier | es |
dc.relation.ispartof | Annales de l'Institut Fourier. | |
dc.rights | Attribution-NonCommercial-NoDerivatives 4.0 Internacional | * |
dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/4.0/ | * |
dc.subject | Proper homotopy | es |
dc.subject | semistability at infinity | es |
dc.subject | ascending HNN-extension | es |
dc.subject | group presentation | es |
dc.title | Lifting Semistability in Finitely Generated Ascending HNN-Extensions | es |
dc.type | info:eu-repo/semantics/article | es |
dcterms.identifier | https://ror.org/03yxnpp24 | |
dc.type.version | info:eu-repo/semantics/publishedVersion | es |
dc.rights.accessRights | info:eu-repo/semantics/openAccess | es |
dc.contributor.affiliation | Universidad de Sevilla. Departamento de Geometría y Topología | es |
dc.contributor.group | Universidad de Sevilla. FQM189: Homotopia Propia | es |
dc.journaltitle | Annales de l'Institut Fourier | es |