Göttingen’s Multiple Avenues Towards Quantum Mechanics

Kurt Schönhammer

Carl S. Helrich

Michael Schaaf

Maria Goeppert Mayer

David Ferry

All alternative interpretations have at their roots some form of disgust at the Copenhagen–Gottingen philosophy, and all have a desire to seek an alternative truth for the understanding of quantum mechanics. The alternative view is of an intrinsic reality prior to the measurement, as discussed by A. Einstein, and by most of the founders of the wave theory of quantum mechanics. A key point of Neils Bohr’s arguments with Einstein, particularly with regard to the Einstein–B. Podolsky–N. Rosen type of experiments, was that one could not make multiple measurements on the same particle, or quantum system. In his view, the measurement itself defined the quantum system. With the arrival of the Schrodinger equation, quantum mechanics had a causal, deterministic equation of motion for the wave function. Perturbation theory, based upon the Schrodinger equation, provided transition details that undermined the assertions of quantum jumps.

Malcolm S. Longair

Göttingen and Copenhagen were the undoubted capitals of the new discipline of quantum mechanics. The expertise in experimental and mathematical physics and in pure mathematics made Göttingen the epicentre of the revolution which was taking place in the mathematical physics of quanta. Whilst this was to remain the case for the next few years, other actors soon appeared on the scene who were to contribute to Born's ‘tangle of interconnected alleys’. What was truly remarkable was how quickly the different approaches to the problems of quantum theory were developed and the rapid assimilation of all of them into a coherent and self-consistent theory of quantum mechanics. Whilst the theory itself was completed relatively quickly, the understanding of its physical content was to take many more years. The new players on the scene included Paul Dirac at Cambridge, Erwin Schrödinger in Vienna and Norbert Wiener at the Massachusetts Institute of Technology. Each of them brought quite new approaches to the development of quantum theory – their innovations were to supersede the matrix mechanics of Born, Heisenberg and Jordan, but there can be no doubt that the success of that theory indicated clearly the route ahead. They were however to involve the introduction of new mathematical techniques into the description of quantum phenomena. Dirac's approach to quantum mechanics Paul Dirac was trained as an electrical engineer at Bristol University, but he had a very strong mathematical bent. He was a solitary character who was notoriously quiet and self-effacing. He simply worked things out on his own.