Pedro G. Ferreira is Professor of Astrophysics at the University of Oxford and a fellow and tutor in Physics at Oriel College, Oxford. He studied and worked at Imperial College in London, at the University of California at Berkeley and at CERN in Geneva. He has held visiting positions at University of Edinburgh, at the Albert Einstein Institute in Berlin and at Columbia University in New York. His area of expertise is cosmology, the early universe and Einstein’s general theory of relativity. His most recent book, The Perfect Theory: A Century of Geniuses and the Battle over General Relativity, has been published in over 20 countries and was shortlisted for the 2014 Royal Society Winton Science Book Prize.