On Mon, 15 Oct 2012 09:10:47 -0700, etpm wrote:

I was watching a lecture about QED given by Richard Feynman. Part of the
lecture was about the reflection of light. This is what I think he said,
paraphrased: When shining a light at a reflective surface the
probabability that the light will take the shortest path or the longest
path to a detector, placed anywhere, is equal. However, the AMPLITUDE
of the probability is not equal, but varies. The light particles with
the highest amplitude are the ones we see when the incident angle and
the exit angle are the same, the shortest path. So I think Feynman said
the probablity can be the same but the amplitude of the probability can
be different. Is that correct? If so, can anyone point me to a web site
that explains this in a way a layman can sort of understand?
Thanks,
Eric

Are you sure he didn't mean that the photon was the same everywhere, but
that the amplitude of the probability was different from place to place?

AFAIK, "probability" and "probability amplitude" are the same thing --
either quantum physicists use these terms differently than I'm used to
(possible), or you misheard he said (presumably possible, although I
don't know how many times you listened), or he _meant_ what I'm saying
above (or something similar) but he didn't state it well.

--
My liberal friends think I'm a conservative kook.
My conservative friends think I'm a liberal kook.
Why am I not happy that they have found common ground?

Tim Wescott, Communications, Control, Circuits & Software
http://www.wescottdesign.com