Cosmic distance duality relation in light of time-delayed strong gravitational lensing*

Abstract The cosmic distance duality relation (DDR), which links the angular-diameter and luminosity distances, is a cornerstone in modern cosmology. Any deviation from DDR may indicate new physics beyond the standard cosmological model. In this study, we used four high-precision time-delayed strong gravitational lensing (SGL) systems provided by H0LiCOW to test the validity of DDR. To this end, we directly compared the angular-diameter distances from these SGL systems with the luminosity distances from the latest Pantheon+ compilation of SNe Ia. To reduce the statistical errors arising from redshift matching, a Gaussian process method was applied to reconstruct the distance-redshift relation from the Pantheon+ dataset. We parameterized the possible violation of DDR in three different models. All results confirm the validity of DDR at confidence level. Additionally, Monte Carlo simulations based on the future LSST survey indicated that the precision of DDR could reach the level with 100 SGL systems.