On the geometry of positive cones in finitely generated groups
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.
2022 | |
Ordered groups Hyperbolic groups Nonpositively curved groups |
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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) |
Sumario: | Publicado también en: Journal of the London Mathematical Society, 2022, 106(4). DOI: 10.1112/jlms.12657 |
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