Douglas Hartree and Early Computations in Quantum Mechanics

Douglas Hartree, who was a mathematical physicist at the University of Manchester and the University of Cambridge during the first half of this century, examined the possibilities for numerical solutions of the many-body problem in quantum mechanics which did not permit analytic, closed-form results. In an attempt to surmount the mathematical complexities associated with multi-electron atoms, Hartree proposed the method of self-consistent fields as an approximation scheme which would give numerical forms of atomic wave functions via iterative solution of the Schrödinger equation. Hartree was quick to recognize the need for automatic computation, both analog and digital, for the practical implementation of the technique. To this end, he investigated the application of analog differential analyzers to the problem before realizing the superiority of digital computation. The question of the first self-consistent field calculations to be run on an electronic digital machine is addressed in an effort to clarify misinformation in the existing literature about the use of early computers to perform Hartree computations.