The general principles of quantum theory

Published in 1934, this monograph was one of the first introductory accounts of the principles which form the physical basis of the Quantum Theory, considered as a branch of mathematics. The exposition is restricted to a discussion of general principles and does not attempt detailed application to the wide domain of atomic physics, although a number of special problems are considered in elucidation of the principles. The necessary fundamental mathematical methods - the theory of linear operators and of matrics - are developed in the first chapter so this could introduce anyone to the new theory. This is an interesting snapshot of scientific history.