Multi-fluid cosmology in Einstein gravity: analytical solutions
Abstract
We review analytical solutions of the Einstein equations which are expressed in terms of elementary functions and describe Friedmann-Lema\^itre-Robertson-Walker universes sourced by multiple (real or effective) perfect fluids with constant equations of state. Effective fluids include spatial curvature, the cosmological constant, and scalar fields. We provide a description with unified notation, explicit and parametric forms of the solutions, and relations between different expressions present in the literature. Interesting solutions from a modern point of view include interacting fluids and scalar fields. Old solutions, integrability conditions, and solution methods keep being rediscovered, which motivates a review with modern eyes.
Keywords
Cite
@article{arxiv.2107.12488,
title = {Multi-fluid cosmology in Einstein gravity: analytical solutions},
author = {Valerio Faraoni and Sonia Jose and Steve Dussault},
journal= {arXiv preprint arXiv:2107.12488},
year = {2021}
}
Comments
Bibliography expanded and typographical errors corrected. Matches the version to appear in Gen. Relativ. Gravit