Also in His lectures is the 'theory of least time' which explains why the light still goes in straight lines - it does so because it is the most probable.
Feynmann just calls it 'scatter'.
There are two problems with this:
We all have great respect for Feynman, but "Feynman says so" is insufficient justification. Could you provide something more concrete to go on?
If the light goes in straight lines after interacting with electrons, why does Feynman call it 'scatter', which is the opposite of straight lines? Is it possible you misunderstood what Feynman was saying?
I'm not sure about the lectures, but in
QED Feynman does not call it scatter.
I believe that the correct term for "theorem of least time" is "principle of least action".
And, of course, Feynman was pointing out that light does not go in a straight line; in a very real way it goes in all sorts of wacko directions, but almost all of the wacko directions (the ones that are not very close to a straight line) destructively interfere with each other, so the probability amplitude for straight line motion, along the path that takes the least time, is high. And, of course, photons interacting with atoms result in photons being emitted in all different directions (the sky is blue) but under many circumstances there's interference between them and other re-emitted photons, the sum effect of which is another high straight-line probability amplitude.
QED is a great book. When I read that (and I have, many times) I almost think I understand it ... for a while.
This message has been edited by JonF, 03-17-2005 08:51 PM
™ Version 4.2