Kevin Hartnett in Quanta:
It’s not an exaggeration to say that every major advance in physics for more than a century has turned on revelations about symmetry. It’s there at the dawn of general relativity, in the birth of the Standard Model, in the hunt for the Higgs.
For that reason, research across physics is now building to a crescendo. It was touched off by a 2014 paper, “Generalized Global Symmetries,” which demonstrated that the most important symmetries of 20th-century physics could be extended more broadly to apply in quantum field theory, the basic theoretical framework in which physicists work today.
This reformulation, which crystallized earlier work in the area, revealed that disparate observations physicists had made in the past 40 years were really manifestations of the same lurking symmetry. In doing so, it created an organizing principle that physicists could use to categorize and understand phenomena. “That’s really a stroke of genius,” said Nathaniel Craig, a physicist at the University of California, Santa Barbara.
More here.