Quasi-Isotropization of the Inhomogeneous Mixmaster Universe Induced by an Inflationary Process

TL;DR

This paper presents a new inhomogeneous cosmological solution demonstrating how an inflationary process can lead to the quasi-isotropization of the universe, connecting Kasner-like and inflationary regimes through a dynamical mechanism.

Contribution

It introduces a generic inhomogeneous bridge solution in cosmology that models the transition from anisotropic to isotropic universe states during inflation.

Findings

The solution connects Kasner-like and inflationary regimes.

It characterizes the universe's evolution dependence on initial conditions.

Provides a dynamical mechanism for quasi-isotropization during inflation.

Abstract

We derive a ``generic'' inhomogeneous ``bridge'' solution for a cosmological model in the presence of a real self-interacting scalar field. This solution connects a Kasner-like regime to an inflationary stage of evolution and therefore provides a dynamical mechanism for the quasi-isotropization of the universe. In the framework of a standard Arnowitt-Deser-Misner Hamiltonian formulation of the dynamics and by adopting Misner-Chitr\`e-like variables, we integrate the Einstein-Hamilton-Jacobi equation corresponding to a ``generic'' inhomogeneous cosmological model whose evolution is influenced by the coupling with a bosonic field, expected to be responsible for a spontaneous symmetry breaking configuration. The dependence of the detailed evolution of the universe on the initial conditions is then appropriately characterized.