Constraints on frequency-dependent violations of Shapiro delay from GW150914

TL;DR

This paper uses the GW150914 gravitational wave event to place stringent constraints on frequency-dependent violations of the Shapiro delay and Einstein's equivalence principle for gravitons, achieving an accuracy of about 10^{-9}.

Contribution

It introduces a novel method to test frequency-dependent violations of fundamental principles using gravitational wave data from GW150914.

Findings

Constraints on violations of the equivalence principle at the 10^{-9} level.

Demonstrates the use of GW150914 to test fundamental physics principles.

Establishes limits on frequency-dependent Shapiro delay deviations.

Abstract

On 14th September 2015, a transient gravitational wave (GW150914) was detected by the two LIGO detectors at Hanford and Livingston from the coalescence of a binary black hole system located at a distance of about 400 Mpc. We point out that GW150914 experienced a Shapiro delay due to the gravitational potential of the mass distribution along the line of sight of about 1800 days. Also, the near-simultaneous arrival of gravitons over a frequency range of about 100 Hz within a 0.2 second window allows us to constrain any violations of Shapiro delay and Einstein's equivalence principle between the gravitons at different frequencies. From the calculated Shapiro delay and the observed duration of the signal, frequency-dependent violations of the equivalence principle for gravitons are constrained to an accuracy of $\mathcal{O}(10^{-9})$