Good read. It is also refreshing to read how Schrödinger came up with his equation even if it was not clear how to interpret it.

He was attempting to formalize de Broglie's "particles as waves" concept, which, according to the article, "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."

Schrödinger's equation put that claim on firm mathematical grounds. It gave correct predictions. But just what this new "wave function" was remained up to interpretation.

We changed the URL from https://physics.mcmaster.ca/phys3mm3/notes/FelixBlochPhysTod... to one that seems to load more easily.

Is the article available as a regular web page anywhere (i.e. not a pdf?) - if so, we can change it again.