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arXiv · 1305.4654

$γ$ gravity: Steepness control

M. O'Dwyer·S. E. Joras·I. Waga
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Abstract

We investigate a simple generalization of the metric exponential $f(R)$ gravity theory that is cosmologically viable and compatible with solar system tests of gravity. We show that, as compared to other viable $f(R)$ theories, its steep dependence on the Ricci scalar $R$ facilitates agreement with structure constraints, opening the possibility of $f(R)$ models with equation-of-state parameter that could be differentiated from a cosmological constant ($w_{de}=-1$) with future surveys at both background and perturbative levels.

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M. O'Dwyer, S. E. Joras, I. Waga. 2013-09-10. $γ$ gravity: Steepness control. https://doi.org/10.1103/physrevd.88.063520

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