Introducing scale symmetry
R. Jackiw · Physics Today · 1972
When symmetries are present the solution of almost any physical problem is simplified, because we can get at the properties of a system without completely solving all the equations that describe the system. In high-energy physics, symmetry principles have been studied with an eye to circumventing two obstacles to the understanding of elementary particles: lack of precise knowledge about interparticle forces (with the exception of electromagnetism) and the mathematical intractability of any realistic models that propose to explain observed particle phenomena.