Richard Feynman Lecture on Quantum Electrodynamics: QED. 6/8

[ienjoyapples]

im not going out tonight. this is gonna be my friday night.

[anand308]

Despite the fact that Feynman says terms for things aren't as important as their meaning, he's still has a remarkable way of using language to stimulate the imagination

[CamiloSanchez1979]

I love how energetic he is to explain it

[myrtlebox]

4:56

Makes me happy that even the great Feynman has to stop and think occasionally. He doesn't want to commit the time-honored factor of 2 error ;-)

[MuonRay]

@myrtlebox This is similar to a Fresnel Zone problem. As the axis of the aperture moves towards the aperture, the light field at the axis alternates between darkness & light. This is due to the interference between light travelling from different regions of the aperture (in this case circular) being either destructive or constructive due to the number of zones on the axis, where light is π radians (lambda/2) out of phase. even number=destructive interference,odd number=constructive interference.

[myrtlebox]

@MuonRay Muon! Thanks so much for uploading. Yes, I know the theory. I've read his book QED perhaps a dozen times. I was just laughing at his momentary concern whether it was lambda or (lambda/2) for the dark/light fringes.

I actually had the chance to meet and talk with him briefly in 1979. I was applying to Caltech, but eventually went to Berkeley.

[nikanj]

I wish I were alive to see him lecture in person.

[prasoonpandey2000]

hey guys!why only 12 likes??

just see any Feynman video & press like.that's the way to do it