Solar system constraints on f(G) gravity models

TL;DR

This paper investigates whether certain f(G) gravity models, which could explain late-time cosmic acceleration, are compatible with solar system tests, finding that many such models can satisfy local gravity constraints.

Contribution

It analyzes solar system constraints on f(G) gravity models and demonstrates their viability in fitting both cosmological and local gravity observations.

Findings

f(G) models can be consistent with solar system tests

modifications to GR are small enough in these models

models can explain cosmic acceleration without conflicting with local experiments

Abstract

We discuss solar system constraints on f(G) gravity models, where f is a function of the Gauss-Bonnet term G. We focus on cosmologically viable f(G) models that can be responsible for late-time cosmic acceleration. These models generally give rise to corrections of the form epsilon*(r/rs)^p to the vacuum Schwarzschild solution, where epsilon = H^2 rs^2 << 1, rs is the Schwarzschild radius of Sun, and H is the Hubble parameter today. We generally estimate the strength of modifications to General Relativity in order to confront models with a number of experiments such as the deflection of light and the perihelion shift. We show that cosmologically viable f(G) models can be consistent with solar system constraints for a wide range of model parameters.