For instance, the theory of gravity is a gauge theory and so is the theory describing the strong interactions. The theory of superstrings which endeavours to combine Einstein's general relativity with quantum mechanics, is the most radical gauge theory. Some of the most recent gauge theories are not only mathematically complicated but also conceptually difficult to follow. In order to extract useful information from these theories, researchers need to use clever techniques which reduce the horrendous algebra and thus make the inherent properties transparent. Since 1983 physical gauges have become increasingly popular, especially in such sophisticated theories as quantum chromodynamics and superstrings.
Current research aims at developing mathematically rigorous procedures for physical gauges.
During the past two years, emphasis has been on the quantization of non-Abelian gauge theories in the noncovariant Coulomb gauge, which has perplexed theorists for 30 odd years. G. Leibbrandt and J. Williams. G. Leibbrandt and M. Staley. G. Leibbrandt and J.D. Williams. S. Fachin and G. Leibbrandt.