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arXiv · 1711.08026

Cosmic acceleration in asymptotically Ricci flat Universe

Luisa G. Jaime·Marcelo Salgado
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Abstract

We analyze the evolution of a Friedmann-Robertson-Walker spacetime within the framework of $f(R)$ metric gravity using an exponential model. We show that $f(R)$ gravity may lead to a vanishing effective cosmological constant in the far future (i.e. $R\rightarrow 0$) and yet produce a transient accelerated expansion at present time with a potentially viable cosmological history. This is in contrast with several $f(R)$ models which, while viable, produce in general a non-vanishing effective cosmological constant asymptotically in time ($R\rightarrow 4Λ_{\rm eff}$). We also show that relativistic {stars in asymptotically flat spacetimes can be supported within this framework without encountering any singularity, notably in the Ricci scalar $R$.

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Luisa G. Jaime, Marcelo Salgado. 2017-11-21. Cosmic acceleration in asymptotically Ricci flat Universe. https://doi.org/10.1103/physrevd.98.084045

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