Re: Light on its path...

marcofuics wrote:
I can demonstrate that the only
acceptable case is that A emits only if it knows that somewhere
(arount itself) there is B ready to accept....
Do you know that photons (or light... or whatever you use to describe
this entity "Luminifera") are those that minimize their own path from
source to destination?
Well, how can they minimize a path if they don't know where it ends?

In the PERTURBATION APPROXIMATION to QED you are correct -- photons always have a definite emission point and a definite absorption point.

But in QED itself this is not true (the Lagrangian has no such requirement). Do not confuse the perturbation approximation to QED with QED itself.


Tom Roberts
.

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