Probing the large-scale structure of the universe through gravitational-wave observations

TL;DR

This paper explores how future third-generation gravitational-wave detectors can map the universe's large-scale structure by analyzing binary black hole clustering, offering an independent cosmological probe beyond traditional galaxy surveys.

Contribution

It introduces a novel method using GW source locations to measure large-scale structure, demonstrating its effectiveness with simulated data and potential for long-term observations.

Findings

Bias factor can be recovered within 33% after 10 years of data collection.

Method is statistically significant with 5000 simulated BBHs.

Independent of electromagnetic observations for probing cosmic structure.

Abstract

The improvements in the sensitivity of the gravitational wave (GW) network enable the detection of several large redshift GW sources by third-generation GW detectors. These advancements provide an independent method to probe the large-scale structure of the universe by using the clustering of the binary black holes. The black hole catalogs are complementary to the galaxy catalogs because of large redshifts of GW events, which may imply that binary black holes (BBHs) are a better choice than galaxies to probe the large-scale structure of the universe and cosmic evolution over a large redshift range. To probe the large-scale structure, we used the sky position of the binary black holes observed by third-generation GW detectors to calculate the angular correlation function (ACF) and the bias factor of the population of binary black holes. This method is also statistically significant as 5000 BBHs are simulated. Moreover, for the third-generation GW detectors, we found that the bias factor can be recovered to within 33$\%$ with an observational time of ten years. This method only depends on the GW source-location posteriors; hence, it can be an independent method to reveal the formation mechanisms and origin of the BBH mergers compared to the electromagnetic method.