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arXiv · 2107.05046

Probing modified gravitational wave propagation with strongly lensed coalescing binaries

Andreas Finke·Stefano Foffa·Francesco Iacovelli·Michele Maggiore·Michele Mancarella
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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 $\Xi_0$ that characterizes modified GW propagation, without the need of imposing a prior on $H_0$. A LIGO/Virgo/Kagra network at target sensitivity might already get a significant measurement of $\Xi_0$, while a third generation GW detector such as the Einstein Telescope could reach a very interesting accuracy.

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Andreas Finke, Stefano Foffa, Francesco Iacovelli, Michele Maggiore, Michele Mancarella. 2021-07-11. Probing modified gravitational wave propagation with strongly lensed coalescing binaries. https://doi.org/10.1103/physrevd.104.084057

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