You know about the Ultraviolet catastrophe?

Physics Explained Ultraviolet Catastrophe: https://youtu.be/rCfPQLVzus4

This Veritassium Video goes back further in time and talks about Action, and the Genesis of this idea. https://youtu.be/qJZ1Ez28C-A

Chemistorian, The history of Atomic Theory. https://youtu.be/SqYPrA7upiE