Higher-derivative gravity in brane world models

Abstract

We investigate brane world models in higher-derivative gravity theories where the gravitational Lagrangian is an arbitrary function of the Ricci scalar. Making use of the conformal equivalence of such gravity models and Einstein-Hilbert gravity with a scalar field, we deduce the main features of higher-derivative gravity brane worlds. We solve for a gravity model that has corrections quadratic in the Ricci scalar and show one can evade both fine-tuning and the need for a bulk cosmological constant. An analysis of tensor and scalar perturbations shows gravity is localized on the brane and we recover the Newtonian limit.