English

The \gamma\ parameter in Brans-Dicke-like (light-)Scalar-Tensor theory with a universal scalar/matter coupling

General Relativity and Quantum Cosmology 2013-09-26 v1 High Energy Physics - Theory Mathematical Physics math.MP

Abstract

The post-Newtonian parameter \gamma\ resulting from a universal scalar/matter coupling is investigated in Brans-Dicke-like Scalar-Tensor theories where the scalar potential is assumed to be negligible. Conversely to previous studies, we use a perfect fluid formalism in order to get the explicit scalar-field equation. It is shown that the metric can be put in its standard post-Newtonian form. However, it is pointed out that 1-\gamma\ could be either positive, null or negative for finite value of \omega_0, depending on the coupling function; while Scalar-Tensor theories without coupling always predict \gamma<1 for finite value of \omega_0.

Keywords

Cite

@article{arxiv.1309.0091,
  title  = {The \gamma\ parameter in Brans-Dicke-like (light-)Scalar-Tensor theory with a universal scalar/matter coupling},
  author = {Olivier Minazzoli},
  journal= {arXiv preprint arXiv:1309.0091},
  year   = {2013}
}

Comments

6 pages, accepted in Phys. Rev. D. arXiv admin note: substantial text overlap with arXiv:1208.2372