Malcolm Longair, CBE, FRS, FRSE, is Jacksonian Professor Emeritus of Natural Philosophy at the University of Cambridge. He was Astronomer Royal for Scotland from 1980 to 1990 and Head of the Cavendish Laboratory from 1997 to 2005. His books with Cambridge University Press include 'High Energy Astrophysics' (2011), 'The Cosmic Century' (2006), 'Quantum Concepts in Physics' (2013), 'Maxwell's Enduring Legacy' (2016) and 'Theoretical Concepts in Physics' (2020).