Development of Quantum Theory from Physical Principles

Book derives entire content of quantum theory and its formalism on basis of two physical notions: (1) the existence of (unspecified) pairs of “conjugate observables” that do not have exact values simultaneously, and (2) the required form invariance of the equations of physics under transformations between physically equivalent coordinate frames. Author combines the two notions to determine both the known conjugate observables and their properties. Lucid explanation of gauge invariance is used to derive basic interaction terms in equations of motion. Book includes usual applications of quantum mechanics along with a careful development of Dirac theory and an explanation of the spin-statistics theorem.