Probing Fundamental Physics with Strong Gravitational Lensing

Wed 25 Oct, 2017 @12PM, Level 7
Dr. Thomas Collett, Dennis Sciama Fellow
Institute of Cosmology & Gravitation (ICG), Univ. of Portsmouth
Email: thomas.collett[at]

Local measurements of the expansion rate are in tension with those inferred from observations of the distant Universe. Is this the first sign of new physics or merely a sign of systematic errors within individual probes? This key question remains unsolved, because there are only a handful of established probes. Here I will talk about how strong gravitational lensing offers a new window on precision cosmology, shining a new light on the dark Universe.

I will present strong lensing constraints on the expansion rate of the Universe and the equation of state of dark energy. I will also show how lensing combined with stellar dynamics yields the most precise test to date of the validity of General Relativity on extragalactic scales.