Cosmological Models Generalising Robertson-Walker Models

TL;DR

This paper develops generalized cosmological models extending Robertson-Walker metrics by considering spheroidal and pseudo spheroidal spatial geometries, analyzing their solutions during different cosmic eras.

Contribution

It introduces a new class of cosmological models with spheroidal spatial sections and derives their solutions in radiation- and matter-dominated periods.

Findings

Generalized models with spheroidal geometries are consistent with Einstein's equations.

Solutions are obtained for different cosmic eras.

The models extend standard Robertson-Walker cosmologies.

Abstract

Considering the physical 3-space t = constant of the spacetime metrics as spheroidal and pseudo spheroidal, cosmological models which are generalizations of Robertson-Walker models are obtained. Specific forms of these general models as solutions of Einstein's field equations are also discussed in the radiation- and the matter-dominated eras of the universe.