### Averaging generalized scalar field cosmologies I: locally rotationally symmetric Bianchi III and open Friedmann-Lemaitre-Robertson-Walker models

### Abstract

Scalar field cosmologies with a generalized harmonic potential and a matter fluid with a barotropic Equation of State (EoS) with barotropic index gamma for locally rotationally symmetric (LRS) Bianchi III metric and open Friedmann-Lemaitre-Robertson-Walker (FLRW) metric are investigated. Methods from the theory of averaging of nonlinear dynamical systems are used to prove that time-dependent systems and their corresponding time-averaged versions have the same late-time dynamics. Therefore, simple time-averaged systems determine the future asymptotic behavior. Depending on values of barotropic index gamma late-time attractors of physical interests for LRS Bianchi III metric are Bianchi III flat spacetime, matter dominated FLRW universe (mimicking de Sitter, quintessence or zero acceleration solutions) and matter-curvature scaling solution. For open FLRW metric late-time attractors are a matter dominated FLRW universe and Milne solution. With this approach, oscillations entering nonlinear system through Klein-Gordon (KG) equation can be controlled and smoothed out as the Hubble factor H - acting as a time-dependent perturbation parameter - tends monotonically to zero. Numerical simulations are presented as evidence of such behaviour.

### Más información

Título según WOS: | Averaging generalized scalar field cosmologies I: locally rotationally symmetric Bianchi III and open Friedmann-Lemaitre-Robertson-Walker models |

Título de la Revista: | EUROPEAN PHYSICAL JOURNAL C |

Volumen: | 81 |

Número: | 5 |

Editorial: | Springer |

Fecha de publicación: | 2021 |

DOI: |
10.1140/EPJC/S10052-021-09185-7 |

Notas: | ISI |