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arXiv · 1210.1521

Cosmology with Eddington-inspired Gravity

James H. C. Scargill·Maximo Banados·Pedro G. Ferreira
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Abstract

We study the dynamics of homogeneous, isotropic universes which are governed by the Eddington-inspired alternative theory of gravity which has a single extra parameter, $κ$. Previous results showing singularity-avoiding behaviour for $κ> 0$ are found to be upheld in the case of domination by a perfect fluid with equation of state parameter $w > 0$. The range $-1/3 < w < 0$ is found to lead to universes which experience unbounded expansion rate whilst still at a finite density. In the case $κ< 0$ the addition of spatial curvature is shown to lead to the possibility of oscillation between two finite densities. Domination by a scalar field with an exponential potential is found to also lead to singularity-avoiding behaviour when $κ> 0$. Certain values of the parameters governing the potential lead to behaviour in which the expansion rate of the universe changes sign several times before transitioning to regular GR-like behaviour.

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James H. C. Scargill, Maximo Banados, Pedro G. Ferreira. 2013-01-07. Cosmology with Eddington-inspired Gravity. https://doi.org/10.1103/physrevd.86.103533

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