Pedro G. Ferreira is Professor of Astrophysics at the University of Oxford. Originally from Portugal, he has studied and worked in London, Berkeley and at CERN in Geneva. His area of expertise is cosmology, focusing on the physics of the early universe and with a special interest in Einstein’s general theory of relativity. He has published over 150 papers in international journals and conference proceedings and has delivered over 100 talks at universities, institutes and conferences all over Europe, America, Asia and Africa. His most recent book, The Perfect Theory: A Century of Geniuses and the Battle over General Relativity was shortlisted for the 2014 Royal Society-Winton Prize for Science Books and is published in over 20 countries.