Summary

We show how quadruply lensed GW events (which already come with good localization) can be used to constrain modified GW propagation without prior knowledge of H₀ already at 2G detectors, with the prospects greatly improving at 3G detectors.

Contribution

I produced most of the results and figures within this paper, wrote the necessary code, and also contributed to the development of the theoretical framework.

Abstract

It has been recently shown that quadruply lensed gravitational-wave (GW) events due to coalescing binaries can be localized to one or just a few galaxies, even in the absence of an electromagnetic counterpart. We discuss how this can be used to extract information on modified GW propagation, which is a crucial signature of modifications of gravity at cosmological scales. We show that, using quadruply lensed systems, it is possible to constrain the parameter Ξ₀ that characterizes modified GW propagation, without the need of imposing a prior on H₀. A LIGO/Virgo/Kagra network at target sensitivity might already get a significant measurement of Ξ₀, while a third-generation GW detector such as the Einstein Telescope could reach a very interesting accuracy.

Links

arXiv: 2107.05046 [gr-qc]

Publisher DOI: 10.1103/PhysRevD.104.084057