Constraints on the cosmic distance duality relation with simulated data of gravitational waves from the Einstein Telescope

Understand

The cosmic distance duality relation (CDDR) has been test through several astronomical observations in the last years.

• This relation establishes a simple equation relating the angular diameter ($D_A$) and luminosity ($D_L$) distances at a redshift $z$, $D_LD_A^{-1}(1+z)^{-2}=\eta=1$.
• However, only very recently this relation has been observationally tested at high redshifts ($z \approx 3.6$) by using luminosity distances from type Ia supernovae (SNe Ia) and gamma ray bursts (GRBs) plus angular diameter distances from strong gravitational lensing (SGL) observations.
• The results show that no significant deviation from the CDDR validity has been verified.