Thanks. I guess I care more about understanding how the world works than about calculation efficiency. (I'd probably have a different view if I was trying to get something actually done. :-)
> The interface that you're describing is between a region where ωλωλ is larger and a region
> where it is smaller. However, the frequency ωω is unaffected: for every wave crest that
> arrives at the interface another wave crest leaves it. The [outgoing] peaks are more closely
> spaced (λλ is...
Okay. Good. This is useful, thank you all. Let me explain why I’m on about this.
I have always been bothered by the “wave train” explanation of why light bends at the interface between two media of different refractive indexes (indices?) - even Feynman gives this seeming crazy explanation...
Yes, more atoms in an excited state than in the ground state, (or a lower state), right? At the interface you have higher absorption so excitation, and the photons that follow right behind should cause SE on those, no? So at least increased coherence if not lasing?
Thank you, Peter. I take from your note that the photon view isn't really appropriate (or anyway isn't optimal) for describing refraction; from the photon point of view, the speed is a group phenomenon (i.e., the light travels between ab/em events at c (not slower). But, per Dale's note, my...
If the light slows at an interface, what happens to the photons coming in after the slowed ones? Can these cohere with the leading (slowed) ones and create what amounts to a FEL?