https://doi.org/10.1140/epjc/s10052-017-5419-z
Regular Article - Theoretical Physics
Is exponential gravity a viable description for the whole cosmological history?
1
Institut de Ciències de l’Espai, ICE/CSIC-IEEC, Carrer de Can Magrans s/n, Bellaterra, 08193, Barcelona, Spain
2
Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
3
Tver state university, 170002, Sadovyj per. 35, Tver, Russia
4
National Research Tomsk State University, 634050, Tomsk, Russia
5
Tomsk State Pedagogical University, 634061, Tomsk, Russia
* e-mail: saez@ice.csic.es
Received:
21
September
2017
Accepted:
25
November
2017
Published online:
13
December
2017
Here we analyse a particular type of F(R) gravity, the so-called exponential gravity which includes an exponential function of the Ricci scalar in the action. Such a term represents a correction to the usual Hilbert–Einstein action. By using Supernovae Ia, Barionic Acoustic Oscillations, Cosmic Microwave Background and H(z) data, the free parameters of the model are well constrained. The results show that such corrections to General Relativity become important at cosmological scales and at late times, providing an alternative to the dark energy problem. In addition, the fits do not determine any significant difference statistically with respect to the CDM model. Finally, such model is extended to include the inflationary epoch in the same gravitational Lagrangian. As shown in the paper, the additional terms can reproduce the inflationary epoch and satisfy the constraints from Planck data.
© The Author(s), 2017