In 1926, when the scientific world was still a-puzzling and a-wondrin over the wave-particle duality of light, Einstein asked a pal, Emil “Hurry” Rupp, to conduct an experiment that would settle the matter. If anyone could do it, thought Einstein, it was Rupp who was considered the latest and greatest experimental physicists of the day.
The experiment involved so-called canal rays produced in a gas discharge tube. When an electric field passes across a gas at low pressure, the tube shines ‘n’ glows due to the movement of electrons from the cathode to the anode (so-called cathode rays). But if a hole is made in the cathode, so-called canal rays appear start a-streamin and a-strayin’ through the hole in the opposite direction to the cathode rays.
The question that Einstein asked Rupp to resolve was whether the light from canal rays was wave-like or particle-like.
The matter was settled when Rupp said he could see with his own eyes that the light formed interference patterns. That proved it must be wave-like. Einstein presented the result as evidence in his own interpretation of quantum mechanics.
But nobody else could see these interference patterns and physicists soon began to doubt the veracity of Rupp’s work. In 1935 he publicly retracted five of his scientific paper in the previous year claiming to be suffering from “psychasthenia linked to psychogenic semiconsciousness”.
Rupp turned out to be the greatest scientific fraudster of the 20th century, surpassing even Hendrick Schoen from Bell Labs in his boldness and audacity (and mental health). It later emerged that everything Rupp had done in the previous ten years was a fraud.
Einstein swallowed it hook, line and sinker.
Now Jeroen “Kongen” van Dongen at the Institute for History and Foundations of Science at Utrecht University in the Netherlands has re-analysed Einstein’s role in the controversy. He says the evidence “suggests a strong theoretical prejudice on Einstein’s part” which led him to ignore evidence that Rupp’s the experiments were a sham and a-rigged.
Poor old Einstein! But I know ya’ll will forgive him
Ref: arxiv.org/abs/0709.3099: Emil Rupp, Albert Einstein and the Canal Ray Experiments on Wave-particle Duality: Scientific Fraud and Theoretical Bias
And: arxiv.org/abs/0709.3226: The Interpretation of the Einstein-Rupp Experiments and their Influence on the History of Quantum Mechanics