RT Journal Article T1 Cartan subgroups and regular points of o‐minimal groups A1 Baro González, Elías A1 Berarducci, Alessandro A1 Otero, Margarita AB Let G be a group definable in an o-minimal structure M. We prove that the union of the Cartan subgroups of G is a dense subset of G. When M is an expansion of a real closed field we give a characterization of Cartan subgroups of G via their Lie algebras which allow us to prove firstly, that every Cartan subalgebra of the Lie algebra of G is the Lie algebra of a definable subgroup – a Cartan subgroup of G –, and secondly, that the set of regular points of G – a dense subset of G – is formed by points which belong to a unique Cartan subgroup of G. PB London Mathematical Society SN 1469-7750 YR 2019 FD 2019-10-01 LK https://hdl.handle.net/20.500.14352/13777 UL https://hdl.handle.net/20.500.14352/13777 LA eng NO Ministerio de Ciencia e Innovación (España) NO Ministerio de Economía y Competitividad (España) NO Universidad Complutense de Madrid NO MIUR DS Docta Complutense RD 9 abr 2025