This launched his 30-year voyage in search of the so-called unified field theory that he hoped would show that these two forces are really manifestations of one grand underlying principle.

NOVA: You mentioned unified field theory. If string theory does lead to the so-called "theory of everything"—I know you don't like that term much—where would theoretical physicists go from there?

Quantum field theory marries the ideas of other ... Quantum electrodynamics (QED) is the unified “electroweak” theory of electromagnetism and the weak nuclear force, which governs nuclear ...