About matter and dark-energy domination eras in Rn gravity or lack thereof
Abstract
We provide further numerical evidence which shows that Rn models in f(R) metric gravity produce a late time acceleration in the Universe or a matter domination era (usually a transient one) but not both. Our results confirm the findings of Amendola et al. [Phys. Rev. Lett. 98, 131302 (2007); PRLTAO0031-9007Phys. Rev. D 75, 083504 (2007); PRVDAQ1550-7998Int. J. Mod. Phys. D 16, 1555 (2007)IMPDEO0218-2718], but using a different approach that avoids the mapping to scalar-tensor theories of gravity, and therefore, spares us from any discussion or debate about frames (Einstein vs Jordan) which are endemic in this subject. This class of models has been used extensively in the literature as an alternative to dark energy, but should be considered ruled out for being inconsistent with the observations. Finally, we discuss a caveat in the analysis by Faraoni [Phys. Rev. D 83, 124044 (2011)PRVDAQ1550-7998], which was used to further constrain these models by using a chameleon mechanism.
- Publication:
-
Physical Review D
- Pub Date:
- January 2013
- DOI:
- 10.1103/PhysRevD.87.024029
- arXiv:
- arXiv:1212.2604
- Bibcode:
- 2013PhRvD..87b4029J
- Keywords:
-
- 04.50.Kd;
- 95.36.+x;
- Modified theories of gravity;
- Dark energy;
- General Relativity and Quantum Cosmology;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 6 pages, 6 figures in 2 panels. Accepted for publication in Phys. Rev. D