Solar System Constraints on f(G) Dark Energy

Understand

Corrections to solar system gravity are derived for f(G) gravity theories, in which a function of the Gauss-Bonnet curvature term is added to the gravitational action.

• Their effects on Newton's law, as felt by the planets, and on the frequency shift of signals from the Cassini spacecraft, are both determined.
• Despite the fact that the Gauss-Bonnet term is quadratic in curvature, the resulting constraints are substantial.
• It is shown that they practically rule out f(G) as a natural explanation for the late-time acceleration of the universe.