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Old June 2nd 10, 01:00 PM posted to rec.radio.amateur.antenna
Cecil Moore Cecil Moore is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 572
Default Question about "Another look at reflections" article.

On Jun 2, 5:33*am, Keith Dysart wrote:
I suggest that you immediately dump any reference that includes
a phrase like "photon energy present in a wave".


If you (and others) will give up on the ridiculous concept of EM wave
energy standing still in standing waves, I will not have to refer to
photons again. Honor the technical fact that EM forward waves (with an
associated ExH energy) and EM reflected waves (with an associated ExH
energy) are always present when standing waves are present and that
those underlying waves (that cannot exist without energy) are moving
at the speed of light in the medium back and forth between impedance
discontinuities. Standing waves are somewhat of an illusion and
according to two of my reference books, do not deserve to be called
waves at all because standing waves do not transfer net energy as
required by the definition of "wave". In short, it is impossible for
EM waves to stand still.

Quoting one of my college textbooks, "Electrical Communication", by
Albert:

"Such a plot of voltage is usually referred to as a *voltage standing
wave* or as a *stationary wave*. Neither of these terms is
particularly descriptive of the phenomenon. A plot of effective values
of voltage, appearing as in Fig. 6(e), *is not a wave* in the usual
sense. However, the term "standing wave" is in widespread use."

From "College Physics", by Bueche and Hecht:

"These ... patterns are called *standing waves*, as compared to the
propagating waves considered above. They might better not be called
waves at all, since they do not transport energy and momentum."

Technically, RF waves *are* light waves, just not *visible* light
waves. All the laws of physics that govern EM waves of light also
apply to RF waves. That you find it inconvenient for your "mashed-
potatoes" theory of energy arguments is not a good reason to abandon
the photonic nature of EM waves. It is actually a good reason to keep
it in mind and abandon the mashed-potatoes energy arguments as human
conceptual constructs that cannot exist in reality. Most of the energy
in an EM wave is kinetic energy. Therefore, it cannot stand still.

There is a wave theory of light, and there is a particle theory
of light, and these two theories do not play well together.


If they are both correct, they should play well together. If there is
any conflict, quantum electrodynamics wins the argument every time.

While in many situations they will yield the same answers, it
is not permissible to mix the concepts from each. Distrust
the conclusions of any exposition which does so.


Actually, distrust the wave theory if it disagrees with QED. Quantum
ElectroDynamics has never been proven wrong.

So feel free to prove that standing waves can exist without the
underlying component traveling waves traveling at the speed of light
in the medium. Feel free to prove that EM wave cancellation does not
"redistribute energy to areas that permit constructive interference"
as the FSU web page explains. Feel free to prove the Melles-Groit web
page wrong when they say such has been proven experimentally. In fact,
the interferometer experiment described here proves that reflected EM
waves, traveling at the speed of light, exist along with the necessary
energy. Take a look at the "non-standard output to screen".

http://www.teachspin.com/instruments...eriments.shtml

I, personally, am not interested in getting the right answer using the
wrong concepts. And I am absolutely sure that your math models do not
dictate reality. It is supposed to be the exact opposite.
--
73, Cecil, w5dxp.com