For everyone who likes news like that: exactly 100 years ago, on January 27, 1926, Erwin Schrödinger submitted his famous paper on “Quantization as an eigenvalue problem” to the Annals of Physics. There he presented for the first time the equation that is named after him nowadays.
The way to the celebrated equation was surprisingly short and straight. On November 23, 2025, Schrödinger held at the ETH Zürich a seminar talk on the work of Louis de Broglie. Felix Bloch, a young student at that time, recalls in Physics Today his recollection:
Schrödinger gave a beautifully clear account of how de Broglie associated a wave with a particle and how he could obtain the quantization rules of Niels Bohr and Sommerfeld by demanding that an integer number of waves should be fitted along a stationary orbit. When he had finished, Debye casually remarked that this way of talking was rather childish. As a student of Sommerfeld he had learned that, to deal properly with waves, one had to have a wave equation.
A few days before Christmas 1925 Schrödinger left Zurich for a short vacation in the Swiss Alps, at a resort near Davos. And when he returned on January 8, he had discovered his famous wave equation. Happy birthday!