4 ms·
I'm not sure that video helps anything. At the very least it confuses the QFT level description of light and electrons with the EM classical description. The "
by l33tman 6y ago
I'm not sure that video helps anything. At the very least it confuses the QFT level description of light and electrons with the EM classical description.
The "waves" you mention add up because each photon sent in through the glass takes all the possible paths, and you need to add up the contributions from all these paths to see where this single photon wants to go. This looks like wave propagation mathematically. The reason the waves add up is because they are all the same photon.
If you send in two unrelated photons, they get their own waves and in that case they do coexist without interference, for all practical field strengths (there are light-on-light scattering effects that come into play at immense field strengths, just now starting to get probed).
- rstuart4133 6y agoYeah, it didn't help anything. But I don't have to invoke QFT and EM to explain why: 1) He's saying the light moves the electrons and the electrons set up a 2nd wave that interferes with the original to produce a lower frequency. That's simple enough. But then he says the lower frequency wave travels slower. Eh, what? We are try to explain is why light travels slower? Ergo, you can use "because it travels slower" in your explanation. 2) That said, the lower frequency does travel slower because light gets split into a spectrum by the glass prism. To me it seems a satisfying answer would not only explain why it got slower, but why slowdown depends on frequency.