English

Ricci curvature non-minimal derivative coupling cosmology with field re-scaling

General Relativity and Quantum Cosmology 2017-08-22 v2

Abstract

In this letter, cosmology of a simple NMDC gravity with ξRϕ,μϕ,μ\xi R \phi_{,\mu}\phi^{,\mu} term and a free kinetic term is considered in flat geometry and in presence of dust matter. A logarithm field transformation ϕ=μlnϕ\phi' = \mu \ln \phi is proposed phenomenologically. Assuming slow-roll approximation, equation of motion, scalar field solution and potential are derived as function of kinematic variables. The field solution and potential are found straightforwardly for power-law, de-Sitter and super-acceleration expansions. Slow-roll parameters and slow-roll condition are found to depend on more than one variable. At large field the re-scaling effect can enhance the acceleration. For slow-rolling field, the negative coupling ξ\xi could enhance the effect of acceleration.

Keywords

Cite

@article{arxiv.1609.08189,
  title  = {Ricci curvature non-minimal derivative coupling cosmology with field re-scaling},
  author = {Burin Gumjudpai and Yuttana Jawralee and Narakorn Kaewkhao},
  journal= {arXiv preprint arXiv:1609.08189},
  year   = {2017}
}

Comments

7 pages, no figures (edited version)