The interpretation of the Einstein-Rupp experiments and their influence on the history of quantum mechanics

The Einstein-Rupp experiments were proposed in 1926 to study the wave versus particle nature of light. Einstein presented a theoretical analysis of these experiments to the Berlin Academy together with the results of Rupp, who claimed to have successfully carried them out. However, as the preceding paper shows, this success was the result of scientific fraud. After exploring the interpretation of the experiments, the present paper shows that they were a relevant part of the background to such celebrated contributions to quantum mechanics as Born's statistical interpretation of the wave function and Heisenberg's uncertainty principle. Yet the Einstein-Rupp experiments have hardly received attention in the literature on the history of quantum mechanics. In part, this is a consequence of self-censorship in the physics community, enforced in the wake of the Rupp affair. Self-censorship among historians of physics may also have played a role.