F. Villalobos | Searcharxiv

arXiv2026

Strong gravitational lensing constraints on interacting dark energy models

The possible interaction between dark matter and dark energy has been proposed as a mechanism to alleviate the coincidence problem and the Hubble tension. Strong gravitational lensing observations provide valuable constraints to test the properties of the dark components of the Universe. We present estimates of cosmological parameters employing strong lensing data for an interaction model Q, proportional to the dark matter density and dependent on the deceleration parameter q. The obtained results are consistent with an accelerating Universe. Furthermore, these results agree with previous studies suggesting that an interaction in the dark sector may help alleviate existing tensions in the expansion history of the Universe and highlight the potential of strong gravitational lensing as an independent cosmological probe.

astro-ph.CO↗

arXiv2026

Study of dark interactions through strong gravitational lenses

The possible interaction between the dark components of the Universe (dark matter and dark energy) stands as an attractive alternative to the standard $\Lambda$CDM cosmological model. In this work, we present a novel analysis of three sign-changeable interaction models whose coupling term $Q$ depends explicitly on the deceleration parameter $q$ and is proportional to different energy densities: dark matter, dark energy, and total energy density. To constrain these models, we combine strong gravitational lensing data on two complementary scales: a sample of early-type galaxies acting as lenses and the galaxy cluster Abell 1689. Our results show that the interaction strength $\beta$ depends on the choice of the coupling term $Q$, with all models yielding negative values of $\beta$, indicative of a dark interaction scenario. The $\beta$ values obtained in this work are significantly larger in magnitude than those previously reported using Type Ia supernovae, CMB, and BAO. The strong-lensing constraints indicate a transition to cosmic acceleration at earlier redshifts ($z_t \sim 1.8-2.1$) than that predicted by the $\Lambda$CDM model, while remaining consistent with cosmic chronometer measurements within the reconstructed confidence regions. Therefore, our study shows that strong gravitational lensing data provide an independent and competitive cosmological probe capable of testing interacting dark energy scenarios. The sensitivity of lensing observables to the expansion history enables access to complementary information about dark-sector dynamics beyond standard cosmological probes.

astro-ph.CO↗