By Fraser, Gordon
By Cox, Professor Brian, Cohen, Andrew, Professor Brian Cox, Andrew Cohen
By Rezzolla, Luciano
By Ryan, Sean G., Norton, Andrew J.
By Chown, Marcus
By DK
By Scharf, Caleb
By Heeren, Fred
By Hendrie, Michael
By Croswell, Ken
By Weinberg, Steven
By Peacocke, Arthur R.
By Gribbin, John
By Carlo Rovelli
By Keith J. Devlin
By Roger Penrose
By Christophe Galfard
By Lawrence M. Krauss
By Leon M. Lederman, Christopher T. Hill
By Joseph Silk (, Savilian Professor of Astronomy, University of Oxford)
By Carl Sagan
By Tony Hey (University of Southampton), Patrick Walters (University of Wales, Swansea)
By Giles Sparrow
By George Musser
By B. Greene
By Frank Close (Professor of Theoretical Physics and Fellow of Exeter College, University of Oxford)
By Clegg, Brian, Pugh, Oliver
By Stephen Hawking (University of Cambridge)
By John Archibald Wheeler