Dark Energy Dominance and Cosmic Acceleration in First Order Formalism
Abstract
The current accelerated universe could be produced by modified gravitational dynamics as it can be seen in particular in its Palatini formulation. We analyze here a specific non-linear gravity-scalar system in the first order Palatini formalism which leads to a FRW cosmology different from the purely metric one. It is shown that the emerging FRW cosmology may lead either to an effective quintessence phase (cosmic speed-up) or to an effective phantom phase. Moreover, the already known gravity assisted dark energy dominance occurs also in the first order formalism. Finally, it is shown that a dynamical theory able to resolve the cosmological constant problem exists also in this formalism, in close parallel with the standard metric formulation.
Keywords
Cite
@article{arxiv.gr-qc/0504057,
title = {Dark Energy Dominance and Cosmic Acceleration in First Order Formalism},
author = {Gianluca Allemandi and Andrzej Borowiec and Mauro Francaviglia and Sergei D. Odintsov},
journal= {arXiv preprint arXiv:gr-qc/0504057},
year = {2010}
}
Comments
21 pages, LaTeX file, no figures. Replaced version to be published on Phys. Rev. D