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arXiv · 1012.3943

Cosmological Consequences of Exponential Gravity in Palatini Formalism

M. Campista·B. Santos·J. Santos·J. S. Alcaniz
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Abstract

We investigate cosmological consequences of a class of exponential $f(R)$ gravity in the Palatini formalism. By using the current largest type Ia Supernova sample along with determinations of the cosmic expansion at intermediary and high-$z$ we impose tight constraints on the model parameters. Differently from other $f(R)$ models, we find solutions of transient acceleration, in which the large-scale modification of gravity will drive the Universe to a new decelerated era in the future. We also show that a viable cosmological history with the usual matter-dominated era followed by an accelerating phase is predicted for some intervals of model parameters.

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M. Campista, B. Santos, J. Santos, J. S. Alcaniz. 2010-12-17. Cosmological Consequences of Exponential Gravity in Palatini Formalism. https://doi.org/10.1016/j.physletb.2011.04.032

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