Astronomy and Astrophysics – Astrophysics – General Relativity and Quantum Cosmology
Scientific paper
2004-04-19
Phys.Rev. D70 (2004) 023503
Astronomy and Astrophysics
Astrophysics
General Relativity and Quantum Cosmology
5 pages and 2 figures. Accepted in PRD
Scientific paper
10.1103/PhysRevD.70.023503
By applying the Palatini approach to the 1/R-gravity model it is possible to explain the present accelerated expansion of the Universe. Investigation of the late Universe limiting case shows that: (i) due to the curvature effects the energy-momentum tensor of the matter field is not covariantly conserved; (ii) however, it is possible to reinterpret the curvature corrections as sources of the gravitational field, by defining a modified energy-momentum tensor; (iii) with the adoption of this modified energy-momentum tensor the Einstein's field equations are recovered with two main modifications: the first one is the weakening of the gravitational effects of matter whereas the second is the emergence of an effective varying "cosmological constant"; (iv) there is a transition in the evolution of the cosmic scale factor from a power-law scaling $a\propto t^{11/18}$ to an asymptotically exponential scaling $a\propto \exp(t)$; (v) the energy density of the matter field scales as $\rho_m\propto (1/a)^{36/11}$; (vi) the present age of the Universe and the decelerated-accelerated transition redshift are smaller than the corresponding ones in the $\Lambda$CDM model.
Alves Daniele S. M.
Kremer Gilberto M.
No associations
LandOfFree
Palatini approach to 1/R gravity and its implications to the late Universe does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Palatini approach to 1/R gravity and its implications to the late Universe, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Palatini approach to 1/R gravity and its implications to the late Universe will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-382249