QCD
Quantum chromodynamics (QCD), the theory of the strong interaction that Frank’s work with David Gross advanced decisively, and for which he received the Nobel prize, is now such a well-established branch of physics that it is used to calculate “backgrounds” in searches for new phenomena. Nevertheless, important challenges remain in applying it to real-world phenomena in nuclear physics, neutron stars, and the early universe. Also, due to its wealth of non-perturbative quantum phenomena, QCD provides an important inspiration and testing-ground for quantum field theory.
More on QCD: Nobel lecture & video
facts lecture prize-presentation documentary
Pioneering papers :
Ultraviolet Behavior of Non-Abelian Gauge Theories: PDF
Asymptotically vol 8, number 10 Free Gauge Theories. PDF
Asymptotically free gauge theories. II: PDF