Probing the cosmic opacity from Future Gravitational Wave Standard Sirens

TL;DR

This paper investigates the potential of future gravitational wave observations to measure cosmic opacity, comparing GW-derived luminosity distances with supernova data using Gaussian Processes, and assesses the universe's transparency.

Contribution

It introduces a method to use future GW data for cosmic opacity testing and explores the universe's transparency through reconstructed luminosity distances.

Findings

Future GW measurements can constrain cosmic opacity with high precision.

A transparent universe is favored at 1σ confidence level.

The method allows for cosmological-independent opacity constraints.

Abstract

In this work, using the Gaussian Process, we explore the potentiality of future gravitational wave (GW) measurement to probe cosmic opacity through comparing its opacity-free luminosity distance (LD) with the opacity-dependent one from type Ia supernovae (SNIa). GW data points are simulated from the third generation Einstein Telescope, and SNIa data are taken from the Joint Light Analysis (JLA) or Pantheon compilation. The advantages of using Gaussian Process are that one may match SNIa data with GW data at the same redshift and use all available data to probe cosmic opacity. We obtain that the error bar of the constraint on cosmic opacity can be reduced to $\sigma_{\epsilon}\sim 0.011$ and $0.006$ at $1\sigma$ confidence level (CL) for JLA and Pantheon respectively in a cosmological-independent way. Thus, the future GW measurements can give competitive results on the cosmic opacity test. Furthermore, we propose a method to probe the spatial homogeneity of the cosmic transparency through comparing the reconstructed LD from the mock GW with the reconstructed one from SNIa data in a flat $\Lambda$CDM with the Gaussian Process. The result shows that a transparent universe is favored at $1\sigma$ CL, although the best-fit value of cosmic opacity is redshift-dependent.