Towards inflation and dark energy cosmologies from modified Gauss Bonnet theory
Abstract
We consider a physically viable cosmological model that has a field dependent Gauss Bonnet coupling in its effective action, in addition to a standard scalar field potential. The presence of such terms in the four dimensional effective action gives rise to several novel effects, such as a four dimensional flat Friedmann Robertson Walker universe undergoing a cosmic inflation at the early epoch, as well as a cosmic acceleration at late times. The model predicts, during inflation, spectra of both density perturbations and gravitational waves that may fall well within the experimental bounds. Furthermore, this model provides a mechanism for reheating of the early universe, which is similar to a model with some friction terms added to the equation of motion of the scalar field, which can imitate energy transfer from the scalar field to matter.
 Publication:

Journal of Cosmology and Astroparticle Physics
 Pub Date:
 June 2006
 DOI:
 10.1088/14757516/2006/06/004
 arXiv:
 arXiv:hepth/0512262
 Bibcode:
 2006JCAP...06..004N
 Keywords:

 High Energy Physics  Theory;
 Astrophysics;
 General Relativity and Quantum Cosmology
 EPrint:
 35 pages, 21 eps figs