Physics and Freedom

In physics, the exclusion principle holds that an electron within an atom, once in orbit, excludes any other particle from occupying exactly the same orbit. That may be as apt a metaphor as any for the unique odyssey of the collection of atoms that was Andrei Sakharov. The life of the dissident Russian physicist — acclaimed as both the creator of the Soviet H-bomb and the conscience of his country — spanned the years from Lenin to Gorbachev, the rise and fall of Soviet communism and the triumph of physics. Who but Sakharov could so personify such an...