Curvature singularities, tidal forces and the viability of Palatini f(R) gravity

Barausse, E.; Sotiriou, T. P.; Miller, J. C.

Curvature singularities, tidal forces and the viability of Palatini f(R) gravity

Authors

Barausse, E.

Sotiriou, T. P.

Miller, J. C.

Description

In a previous paper we showed that static spherically symmetric objects which, in the vicinity of their surface, are well-described by a polytropic equation of state with 3/2<Gamma<2 exhibit a curvature singularity in Palatini f(R) gravity. We argued that this casts serious doubt on the validity of Palatini f(R) gravity as a viable alternative to General Relativity. In the present paper we further investigate this characteristic of Palatini f(R) gravity in order to clarify its physical interpretation and consequences.
15 pages. CQG in press. Part of the material moved to an appendix, discussion on the meV scale predictions of Palatini f(R) gravity added