Prof. Brad DeLong points us to Sidney Coleman’s 1994 lecture, “Quantum Mechanics in Your Face“.  Coleman makes a very clear presentation of the consequences of the Einstein-Podolsky-Rosen paradox and its descendants, most notably Bell’s Inequality, and shows a very simple* proof that all the apparent contradictions come from us readers who are still secretly thinking the world is classical, even as we’re doing quantum mechanics.

Alas, Prof. Coleman’s slides are just barely readable on the YouTube video. (And they weren’t so great in person, as far as I can tell.) I have transcribed them here to the best of my ability. Quantum Mechanics In Your Face: Slides.


  • No attempt has been made to make them less of a mess than the originals.
  • An intermediate step has been added whenever Coleman jumps to the end as soon as the smartest person in the room can see how it’s going to come out. I hate that (whenever I’m not the smartest person in the room).
  • One bullet at the bottom of a slide that never came into focus could not be reconstructed.
  • At the end of the talk, Coleman puts up two pages of algebra side by side on two projectors, to show they are the same. The second page of the two has not been reproduced here because the tiny differences (mostly subscripts and superscripts) were illegible.

* Seriously. You should see the original.  This is simpler even than the Wikipedia page.