Development of the Uncertainty Relation and Its Universal Formulation

Heisenberg's uncertainty principle — or uncertainty relation — is, alongside Einstein's relativity principle, one of the most widely known phrases in physics. Uncertainty relations express incompatible or complementary quantum properties as general trade-off relations. Historically, beyond the textbook "quantum fluctuation" relation, a variety of trade-off relations have been identified, such as the "observer-effect" relation illustrated by the gamma-ray microscope thought experiment and the "measurement accuracy" relation, with many formulations proposed. This seminar sketches a century of development by following these three typical relations, introduces our universal formulation as a recent proposal, and shows how it unifies trade-off relations that had previously been treated separately, before revisiting the significance of the uncertainty principle as a "no-go" theorem in quantum theory.