Jim Al-Khalili is professor of physics at the University of Surrey. He is one of the UK’s best-known science communicators: as well as hosting The Life Scientific on BBC Radio 4, he has presented several BBC TV documentaries. His latest book, The World According to Physics, is published in March 2020 by Princeton University Press. He is a fellow of the Royal Society and lives in Southsea, England. Twitter @jimalkhalili