When “quantum electrodynamics” (QED), the quantum field theory (QFT) describing charged particles and light, was developed in the 1930s, physicists quickly realized it led to undesirable divergences at high energies. A series of attempts to answer whether the theory was (in)consistent led many physicists to seek to replace the theory; there was no satisfactory cure. The most pressing challenge to the consistency of QED, the Landau pole, extended this climate of despair up to the 1950s.
When “quantum chromodynamics” (QCD), the QFT describing the atomic nucleus, was developed in the 1970s, physicists quickly realized it was well-behaved at high energies; it is “asymptotically free.” While QCD also has a Landau pole, this time at low energies, physicists reacted by finding better tools and cleverer ways to use those available. This drive for refinement prevented a consistency crisis like the one from QED despite QCD suffering from the same pathology. Why the double standard?
My work at MPIWG was to chart the development of asymptotic freedom, which remains undertheorized. Now, I have two goals. First, I want to compare the reactions to QCD to those to QED, which Alexander Blum, my group leader at MPIWG, has already charted. Second, with a historical explanation of the double standard, I want to draw some philosophical morals. The morals I draw roughly follow a Kuhnian picture of science, where refinement attitudes illuminate how resourceful physicists become when they lack conceptual resources to navigate a crisis, not in irrational or unreasonable ways.