Having been sequestered from the physics community for two decades, he didn’t have the same preconceptions about what he should or shouldn’t be interested in or be working on. As a result, Sakharov was able to produce and publish papers on the new theory of the strong nuclear force—known as quantum chromodynamics—as well as on general relativity, and on how distributions of matter evolve as space expands. He wasn’t a particle physicist, and he wasn’t a cosmologist. It was precisely this that made it possible for him to become both.
