Differentiating Between Modified Gravity Theories in the Solar System

TL;DR

This paper explores how to distinguish between different modified gravity theories in the Solar System using the LISA Pathfinder mission, focusing on quasi-linear formulations and their observational signatures.

Contribution

It extends previous analyses to include quasi-linear modified gravity theories and assesses their distinguishability via space-based gravitational measurements.

Findings

Instrumental responses differ between theories

Signal to Noise Ratios vary for different models

Constraints can be derived from negative test results

Abstract

Building on previous work, we re-examine the possibility of testing MOdified Newtonian Dynamics near the saddle points of gravitational potentials in the Solar System, through an extension of the forthcoming LISA Pathfinder mission. We extend present analysis to include quasi-linear formulations of these theories, resulting from fully relativistic modified gravity theories. Using similar quantitative and qualitative tools, we demonstrate that in general, both the instrumental response and typical Signal to Noise Ratios for such a test will be different. Finally we investigate constraints from a negative result and parameterised free functions.