Comments on Graviton Propagation in Light of GW150914

TL;DR

This paper discusses how gravitational wave observations, specifically GW150914, can be used to test for Lorentz violation in graviton propagation and compares the velocities of light and gravitational waves, setting very tight constraints.

Contribution

It provides new constraints on Lorentz violation in graviton propagation and the difference in velocities between light and gravitational waves based on GW150914 data.

Findings

Lorentz violation in graviton propagation is tightly constrained.

The velocity difference between light and gravitational waves is less than 10^{-17}.

Observational data can significantly limit alternative gravity theories.

Abstract

The observation of gravitational waves from the Laser Interferometer Gravitational-Wave Observatory (LIGO) event GW150914 may be used to constrain the possibility of Lorentz violation in graviton propagation, and the observation by the Fermi Gamma-Ray Burst Monitor of a transient source in apparent coincidence may be used to constrain the difference between the velocities of light and gravitational waves: $c_g - c_\gamma < 10^{-17}$.