Signals for Lorentz violation in gravitational waves

Lorentz violations in gravitational waves are investigated. Plane-wave solutions for arbitrary gauge-invariant violations in linearized gravity are constructed. Signatures of Lorentz violation include dispersion, birefringence, and anisotropies. Modifications to waves from coalescing compact binaries and to strain signals in gravitational-wave detectors are derived.

Figure 1

Time-domain strain for nonbirefringent dispersion with $\tau {\varsigma }^{(6)0}=20T^3$ (black) and the Lorentz-invariant limit (gray). The Lorentz-invariant strain is generated using the amplitude and phase functions in Ref. [54] with mass ratio $\eta =\frac{1}{4}$.

Figure 2

(a) Time-domain strain and (b) base-10 logarithm of the spectral density for $CPT$-odd birefringence with $\tau {\varsigma }_{(0)}^{(5)}=10T^2$ (black). The Lorentz-invariant limit (gray) is generated using the phase and amplitudes from Ref. [54] with mass ratio $\eta =\frac{1}{4}$. The merger is positioned so that the incident wave is linearly polarized in the Lorentz-invariant limit, and the detector arms are aligned to maximize the conventional sensitivity.