Lorentz Violation and Gravity

TL;DR

This paper reviews recent theoretical and experimental efforts to detect tiny violations of Lorentz symmetry in gravity, highlighting how gravitational experiments like lunar laser ranging and atom interferometry constrain Lorentz violation coefficients.

Contribution

It summarizes recent advances in testing Lorentz symmetry in gravity using experimental data within the SME framework, emphasizing new constraints from recent experiments.

Findings

Lunar laser ranging constrains gravity Lorentz violation coefficients.

Atom interferometry provides stringent limits on Lorentz violation.

Experimental bounds are tightening on Lorentz-violating parameters in gravity.

Abstract

In the last decade, a variety of high-precision experiments have searched for miniscule violations of Lorentz symmetry. These searches are largely motivated by the possibility of uncovering experimental signatures from a fundamental unified theory. Experimental results are reported in the framework called the Standard-Model Extension (SME), which describes general Lorentz violation for each particle species in terms of its coefficients for Lorentz violation. Recently, the role of gravitational experiments in probing the SME has been explored in the literature. In this talk, I will summarize theoretical and experimental aspects of these works. I will also discuss recent lunar laser ranging and atom interferometer experiments, which place stringent constraints on gravity coefficients for Lorentz violation.