 The theory of quantum chromodynamics was formulated beginning in the early 1960s.The theory as we know it today was formulated by Politzer, Gross and Wilczek in 1975.Building on pioneering work by Schwinger, Higgs and Goldstone, the physicists Glashow, Weinberg and Salam independently showed how the weak nuclear force and quantum electrodynamics could be merged into a single electroweak force, for which they received the 1979 Nobel Prize in Physics.