LANL · Attribution

Shared the 2004 Nobel Prize in Physics with Frank Wilczek and David Politzer for discovering asymptotic freedom — the counterintuitive finding that the force binding quarks together inside protons and neutrons grows weaker, not stronger, as the quarks get closer, which let physicists finally treat the strong nuclear force with the mathematical tools used elsewhere in particle physics. He later directed the Kavli Institute for Theoretical Physics at UC Santa Barbara, where he continued working on string theory.