Analysis of birefringence and dispersion effects from spacetime-symmetry breaking in gravitational waves

TL;DR

This paper reviews how gravitational wave observations can be used to detect potential Lorentz and CPT symmetry breaking effects, such as dispersion and birefringence, using an effective field theory approach and Bayesian analysis.

Contribution

It introduces a framework connecting spacetime-symmetry breaking theory with gravitational wave data analysis, including implementation in LIGO-Virgo algorithms and preliminary sensitivity results.

Findings

Gravitational waves can potentially reveal Lorentz and CPT violation effects.

Simulations show measurable modifications in gravitational waveforms due to symmetry breaking.

The method demonstrates high sensitivity of gravitational wave detectors to new physics signals.

Abstract

In this work, we review the effective field theory framework to search for Lorentz and CPT symmetry breaking during the propagation of gravitational waves. The article is written so as to bridge the gap between the theory of spacetime-symmetry breaking and the analysis of gravitational-waves signals detected by ground-based interferometers. The primary physical effects beyond General Relativity that we explore here are dispersion and birefringence of gravitational waves. We discuss their implementation in the open-source LIGO-Virgo algorithm library suite, as well as the statistical method used to perform a Bayesian inference of the posterior probability of the coefficients for symmetry-breaking. We present preliminary results of this work in the form of simulations of modified gravitational waveforms, together with sensitivity studies of the measurements of the coefficients for Lorentz and CPT violation. The findings show the high potential of gravitational wave sources across the sky to probe sensitively for these signals of new physics.