2026-04-17T23:05:40Zhttps://recercat.cat/oai/request

oai:recercat.cat:2117/3438732026-01-23T04:58:54Zcom_2072_1033col_2072_452950

Qualitative study of a model with Rastall gravity Pantazi, Chara Llibre Saló, Jaume Universitat Politècnica de Catalunya. Departament de Matemàtiques Universitat Politècnica de Catalunya. SD - Sistemes Dinàmics de la UPC Àrees temàtiques de la UPC::Matemàtiques i estadística::Equacions diferencials i integrals::Sistemes dinàmics Differential equations Einstein field equations Rastall gravity First integral Global phase portrait Dynamical behaviour Equacions diferencials Equacions de camp d'Einstein We consider the Rastall theory for the flat Friedmann-Robertson-Walker Universe filled with a perfect fluid that satisfies a linear equation of state. The corresponding dynamical system is a two dimensional system of polynomial differential equations depending on four parameters. We show that this differential system is always Darboux integrable. In order to study the global dynamics of this family of differential systems we classify all their non-topological equivalent phase portraits in the Poincaré disc and we obtain 16 different dynamical situations for our spacetime. Peer Reviewed Postprint (published version) 2020-12-17 Article Pantazi, C.; Llibre, J. Qualitative study of a model with Rastall gravity. "Classical and quantum gravity", 17 Desembre 2020, vol. 37, núm. 24, p. 245010-1-245010-23. 0264-9381 https://hdl.handle.net/2117/343873 10.1088/1361-6382/abc188 eng https://iopscience.iop.org/article/10.1088/1361-6382/abc188 http://creativecommons.org/licenses/by-nc-nd/3.0/es/ Open Access Attribution-NonCommercial-NoDerivs 3.0 Spain application/pdf