English

Loop cosmological implications of a non-minimally coupled scalar field

General Relativity and Quantum Cosmology 2007-05-23 v1 Astrophysics

Abstract

Non-minimal actions with matter represented by a scalar field coupled to gravity are considered in the context of a homogeneous and isotropic universe. The coupling is of the form ξ/2ϕ2R-\xi/2 \phi^2 R. The possibility of successful inflation is investigated taking into account features of loop cosmology. For that end a conformal transformation is performed. That brings the theory into the standard minimally coupled form (Einstein frame) with some effective field and its potential. Both analytical and numerical estimates show that a negative coupling constant is preferable for successful inflation. Moreover, provided fixed initial conditions, larger ξ|\xi| leads to a greater number of {\em e}-folds. The latter is obtained for a reasonable range of initial conditions and the coupling parameter and indicates a possibility for successful inflation.

Keywords

Cite

@article{arxiv.gr-qc/0606082,
  title  = {Loop cosmological implications of a non-minimally coupled scalar field},
  author = {Martin Bojowald and Mikhail Kagan},
  journal= {arXiv preprint arXiv:gr-qc/0606082},
  year   = {2007}
}

Comments

10 pages, 4 figures