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arXiv · 2007.11990

Generalized Scalar Field Cosmologies: A Global Dynamical Systems Formulation

Genly Leon·Felipe Orlando Franz Silva
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Abstract

Local and global phase-space descriptions and averaging methods are used to find qualitative features of solutions for the FLRW and the Bianchi I metrics in the context of scalar field cosmologies with arbitrary potentials and arbitrary couplings to matter. The stability of the equilibrium points in a phase-space as well as the dynamics in the regime where the scalar field diverges are studied. Equilibrium points that represent some solutions of cosmological interest such as: several types of scaling solutions, a kinetic dominated solution representing a stiff fluid, a solution dominated by an effective energy density of geometric origin, a quintessence scalar field dominated solution, the vacuum de Sitter solution associated to the minimum of the potential, and a non-interacting matter dominated solution are obtained. All reveal a very rich cosmological phenomenology.

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Genly Leon, Felipe Orlando Franz Silva. 2020-09-25. Generalized Scalar Field Cosmologies: A Global Dynamical Systems Formulation. https://doi.org/10.1088/1361-6382%2Fabc095

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