On the geometry of positive cones in finitely generated groups

Alonso, Juan - Antolín, Yago - Brum, Joaquín - Rivas, Cristóbal

Resumen:

We study the geometry of positive cones of left-invariant total orders (left-order, for short) in finitely generated groups. We introduce the Hucha property and the Prieto property for left-orderable groups. We say that a group has the Hucha property if in any left-order the corresponding positive cone is not coarsely connected, and the Prieto property if in any left-order the corresponding positive cone is coarsely connected. We show that all left-orderable free products have the Hucha property, and that the Hucha property is stable under certain free products with amalgamatation over Prieto subgroups. As an application we show that non-abelian limit groups in the sense of Z. Sela (e.g., free groups, fundamental group of hyperbolic surfaces, doubles of free groups and others) and non-abelian finitely generated subgroups of free -groups in the sense of G. Baumslag have the Hucha property. In particular, this implies that these groups have empty BNS-invariant and that they do not have finitely generated positive cones.


Detalles Bibliográficos
2022
Ordered groups
Hyperbolic groups
Nonpositively curved groups
Inglés
Universidad de la República
COLIBRI
https://hdl.handle.net/20.500.12008/39066
Acceso abierto
Licencia Creative Commons Atribución - No Comercial - Sin Derivadas (CC - By-NC-ND 4.0)
Resumen:
Sumario:Publicado también en: Journal of the London Mathematical Society, 2022, 106(4). DOI: 10.1112/jlms.12657