G1 Cosmologies with Gravitational and Scalar Waves

TL;DR

This paper introduces a new algorithm for creating inhomogeneous scalar field cosmologies with gravitational and scalar waves, revealing insights into their structure, singularities, and late-time behavior.

Contribution

A novel method to generate inhomogeneous massless scalar field cosmologies with a single isometry, expanding the understanding of wave propagation in cosmological models.

Findings

Constructed models with gravitational and scalar waves on inhomogeneous backgrounds

Analyzed early and late time limits of the new cosmological solutions

Discussed the structure of singularities and physical interpretations

Abstract

I present here a new algorithm to generate families of inhomogeneous massless scalar field cosmologies. New spacetimes, having a single isometry, are generated by breaking the homogeneity of massless scalar field $G_2$ models along one direction. As an illustration of the technique I construct cosmological models which in their late time limit represent perturbations in the form of gravitational and scalar waves propagating on a non-static inhomogeneous background. Several features of the obtained metrics are discussed, such as their early and late time limits, structure of singularities and physical interpretation.