Thanks for the great explanation! However, I noticed something at 1:15: The Bloch factor is not the eigenfunction of the translation operator, but the eigenvalue of it. Right?
Really like your videos, thank you very much! A piece of hopefully constructive criticism: Sometime after displaying stuff you get rid of it real quick (e.g. from 0:29 to 0:31). At least for me something like 5 seconds would be a bit more convenient. I caught myself pausing the videos on a regular basis ...