Modifications to Plane Gravitational Waves from Minimal Lorentz Violation

Understand

General Relativity predicts two modes for plane gravitational waves.

• When a tiny violation of Lorentz invariance occurs, the two gravitational wave modes are modified.
• We use perturbation theory to study the detailed form of the modifications to the two gravitational wave modes from the minimal Lorentz-violation coupling.
• The perturbation solution for the metric fluctuation up to the first order in Lorentz violation is discussed.