# Testing Cosmic Distance-Duality Relation from Future Gravitational Wave Standard Sirens

## TL;DR

This paper investigates the potential of future gravitational wave standard siren data from the Einstein Telescope to test the cosmic distance-duality relation, which is fundamental in cosmology and sensitive to new physics.

## Contribution

It demonstrates that simulated future GW measurements can effectively test the CDDR, offering an alternative to traditional methods that rely on photon conservation.

## Key findings

- Future GW data can significantly improve CDDR tests
- Simulated data shows high potential for detecting deviations
- GW measurements are less affected by photon non-conservation

## Abstract

A validation of the cosmic distance-duality relation (CDDR) is crucial because any observational departure from it could be a signal of new physics. In this work, we explore the potentialities of luminosity distance data from the gravitational wave (GW) standard sirens of future Einstein Telescope (ET) to test the CDDR. The angular diameter distance data are used from the galaxy clusters samples and the baryon acoustic oscillation (BAO) measurements. The basic advantage of GW measurements substituting for the observations from the type Ia supernovae (SNIa) is that the luminosity distance from it is insensitive to the non-conservation of the number of photons. By simulating 550 and 1000 data points of future GW measurements in the low redshift range $0<z<1$, we show that the measurements of future GW events will be a powerful tool to test the CDDR.