Lensing of space time around a black hole. At Oxford we study black holes observationally and theoretically on all size and time scales - it is some of our core work. Credit: ALAIN RIAZUELO, IAP/UPMC/CNRS. CLICK HERE TO VIEW MORE IMAGES. Chao LiuVisitor Sub departmentAstrophysics Research groupsThe Square Kilometre Array (SKA)Experimental radio cosmology chao.liu@physics.ox.ac.uk About