The big unsolved problem quantum gravity
The New Scientist Elsevier 207:2767 (2010) viii
The Crossing Statistic: Dealing with Unknown Errors in the Dispersion of Type Ia Supernovae
(2010)
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.
Professor of Astrophysics