Uploaded March 2018 | Updated September 2026, 2 weeks ago

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In this video, I define the expectation value of position for a wavefunction psi and use that to derive the expectation value of momentum as well as the expressions for the position and momentum operator. I then show that in general, any Classical Mechanics quantity can be determined from the wavefunction using a combination of the position and/or momentum operators.

There's quite a bit of math involved, so if you have any questions, let me know in the comments! Stay tuned for the next video (coming soon!) in which I will use the expressions for the momentum and position operators to derive the Heisenberg Uncertainty Principle.

Prerequisites: All the previous videos in both of these playlists (Playlist 1: youtube.com/playlist?list=PLdgVBOaXkb9AtG88OsK_c8FDEBDLCC6_9, Playlist 2: youtube.com/playlist?list=PLdgVBOaXkb9Bv466YnyxslT4gIlSZdtjw)

2nd Postulate Video: youtu.be/-h2lU2FXy48?t=9m30s
Previous Video: youtube.com/watch?v=kUm4q0UIpio

Lecture Notes: drive.google.com/open?id=1ppTeR55YdIXox2ncf0obr8Na8vaFEIbk
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