Atom interferometry tests of local Lorentz invariance in gravity and electrodynamics

TL;DR

This paper reports high-precision atom interferometry experiments testing local Lorentz invariance in gravity and electrodynamics, setting stringent bounds on possible violations at the part per billion level.

Contribution

It provides the first combined bounds on Lorentz violation in gravity and electrodynamics using atom interferometry, improving sensitivity and exploring new experimental configurations.

Findings

Limits on twelve Lorentz violation coefficients at the ppb level.

Derived bounds on six Lorentz violation coefficients from combined data.

Discussion of horizontal interferometers for enhanced sensitivity.

Abstract

We present atom-interferometer tests of the local Lorentz invariance of post-Newtonian gravity. An experiment probing for anomalous vertical gravity on Earth, which has already been performed by us, uses the highest-resolution atomic gravimeter so far. The influence of Lorentz violation in electrodynamics is also taken into account, resulting in combined bounds on Lorentz violation in gravity and electrodynamics. Expressed within the standard model extension or Nordtvedt's anisotropic universe model, we limit twelve linear combinations of seven coefficients for Lorentz violation at the part per billion level, from which we derive limits on six coefficients (and seven when taking into account additional data from lunar laser ranging). We also discuss the use of horizontal interferometers, including atom-chip or guided-atom devices, which potentially allow the use of longer coherence times in order to achieve higher sensitivity.