Speaker
Description
The measured Hubble constant between cosmological probes in the early or late universe are different. This may be real, with profound implications for physics, or due to observational flukes. Measuring the Time Delays between strongly lensed images of quasars or supernovae provides a single-step measurement of H0 in the late universe, fully independent of any other cosmological probe. This requires good lens models as well as precise and accurate time delay measurements from well-sampled (daily) light curves of lensed quasars. Few telescopes around the world offer flexible service mode observations with large collecting area and good seeing. NOT is one of them! I will present results obtained by the TDCOSMO collaboration with the NOT and plans to obtain more in the future, in combination with other telescopes, in the LSST and SKA era.
