Modified Large Distance Newton Potential on a Gauss-Bonnet Brane World

TL;DR

This paper explores a brane world gravity model with higher curvature terms and a scalar field, resulting in modified large distance Newtonian potential similar to the DGP model, but with observational challenges due to scalar coupling.

Contribution

It introduces a ghost-free brane world model with modified large distance gravity without requiring a scalar potential, extending previous models like DGP.

Findings

The model produces a Newton potential similar to DGP.

Suitable parameters yield a ghost-free setup.

Short distance gravity remains scalar-tensor and observationally incompatible.

Abstract

Gravity on a brane world with higher order curvature terms and a conformally coupled bulk scalar field is investigated. Solutions with non-standard large distance gravity are described. It is not necessary to include a scalar field potential in order to obtain the solutions. The resulting Newton potential is qualitatively similar to that of the Dvali-Gabadadze-Porrati (DGP) model. For suitable parameter choices the model is ghost free. Like many other brane gravity models with modified large distance Newton potentials, the short distance gravity is scalar-tensor. The scalar couples with gravitational strength, and so the model is not compatible with observation.