Measuring H0 with strongly lensed quasars

Abstract: Time-delay cosmography with lensed quasars is the only single-step method to measure H0. It can strengthen or alleviate the current "Hubble tension". The method has its own advantages and drawbacks that I will review before presenting the different avenues adopted by the TDCOSMO collaboration to improve results. This includes 1- spatially resolved kinematics of lens galaxies, 2- Hierarchical Bayesian analysis of joint samples of time delay and non-time delay lenses, and 3- massive time delay measurements obtained at high temporal cadence, illustrating the need for medium-size telescope(s) to complement LSST.