Notes on Volume 27, 1931 Mathematical Proceedings of the Cambridge Philosophical Society

We're learning about Landau levels this week which led me to the Darwin's 1931 work on the diamagnetism of a free electron as it reference Landau's work. Perusing through the journal that contained Darwin' article, I found that there were a number of other interesting investigations being carried out in January of 1931.

A.S. Eddington was working on refining the mass of the electron, the proton, and therefore, the universe. He was studying the coupling constant and expounding on what was then known as the "Theory of 137".

L.G. Vedy had been made aware of a number of phenomena that involved the rotation of dielectrics in a Wimshurst machine. He was working out the electromagnetic theory behind these observations. The illustration to the left came from this article.

Finally, N. A. de Bruyne and H. C. Webster had worked out a way to use a thyratron tube to trigger a mechanical event counter for a Geiger counter detector. The article contains a very nice explanation of what a thyratron tube is and how it works.

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