A Model-independent Determination of the Hubble Constant from Lensed Quasars and Supernovae Using Gaussian Process Regression

Strongly lensed quasar systems with time delay measurements provide ?time delay distances,? which are a combination of three angular diameter distances and serve as powerful tools to determine the Hubble constant H-0. However, current results often rely on the assumption of the ?CDM model. Here we use a model-independent method based on Gaussian process to directly constrain the value of H-0. By using Gaussian process regression, we can generate posterior samples of unanchored supernova distances independent of any cosmological model and anchor them with strong lens systems. The combination of a supernova sample with large statistics but no sensitivity to H-0 with a strong lens sample with small statistics but H-0 sensitivity gives a precise H-0 measurement without the assumption of any cosmological model. We use four well-analyzed lensing systems from the state-of-art lensing program H0LiCOW and the Pantheon supernova compilation in our analysis. Assuming the universe is flat, we derive the constraint H(0)72.2;2.1 km s(?1) Mpc(?1), a precision of 2.9%. Allowing for cosmic curvature with a prior of ?[?0.2, 0.2], the constraint becomes H 73.0+ km s- Mpc(-1).