Bengt Nyman from Vaxholm, Sweden · CC BY 2.0

Worked out, with Robert Brout in 1964, the theoretical mechanism by which fundamental particles acquire mass — independently of, and roughly simultaneously with, Peter Higgs's better-known paper on the same idea, which is why physicists increasingly call it the Brout-Englert-Higgs mechanism. The prediction went unconfirmed for nearly half a century until CERN's Large Hadron Collider detected the associated particle in 2012, after which Englert shared the 2013 Nobel Prize in Physics with Higgs. He held a joint appointment at Tel Aviv University's Sackler School and remained professor emeritus at the Université libre de Bruxelles.