Bounding the mass of the graviton using gravitional-wave observations of inspiralling compact binaries

TL;DR

This paper discusses how gravitational-wave observations from inspiralling binaries can be used to set bounds on the graviton's mass by analyzing phase modifications in the waveform, with bounds depending on the source and detector characteristics.

Contribution

It introduces a method to bound the graviton mass using gravitational-wave phase evolution, providing bounds that are independent of source distance and applicable to different detector types.

Findings

Ground-based detectors can bound graviton wavelength to about 6 x 10^{12} km.

LISA can bound the wavelength up to 6 x 10^{16} km.

Bounds are weaker than some astrophysical constraints but are model-independent.

Abstract

If gravitation is propagated by a massive field, then the velocity of gravitational waves (gravitons) will depend upon their frequency and the effective Newtonian potential will have a Yukawa form. In the case of inspiralling compact binaries, gravitational waves emitted at low frequency early in the inspiral will travel slightly slower than those emitted at high frequency later, modifying the phase evolution of the observed inspiral gravitational waveform, similar to that caused by post-Newtonian corrections to quadrupole phasing. Matched filtering of the waveforms can bound such frequency-dependent variations in propagation speed, and thereby bound the graviton mass. The bound depends on the mass of the source and on noise characteristics of the detector, but is independent of the distance to the source, except for weak cosmological redshift effects. For observations of stellar-mass compact inspiral using ground-based interferometers of the LIGO/VIRGO type, the bound on the graviton Compton wavelength is of the order of $6 \times 10^{12}$ km, about double that from solar-system tests of Yukawa modifications of Newtonian gravity. For observations of super-massive black hole binary inspiral at cosmological distances using the proposed laser interferometer space antenna (LISA), the bound can be as large as $6 \times 10^{16}$ km. This is three orders of magnitude weaker than model-dependent bounds from galactic cluster dynamics.