Thread: Dual-Z0 Stubs
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Old May 19th 09, 12:37 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
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Default Dual-Z0 Stubs

Jim Kelley wrote:
For instance, standing waves
consist of photons that cannot stand still.


As opposed to consisting of photons that _can_ stand still? :-)


Some people will argue that EM standing waves are
actually standing still which implies that photons
can stand still which they cannot. This is easy
to see if one visualizes standing waves of light
in free space as Hecht does in "Optics". There's
no voltage or current to muddy the issue. One is
forced to deal with photonic E-fields and H-fields
in free space.

It's the same old misconception. If net energy
transfer is zero, some believe that means the
energy carriers are not moving. But as Hecht
says, it is the *profile* of the standing wave
that doesn't move. The standing wave profile
is a human abstraction and according to Hecht,
standing waves do not deserve to be called waves
at all: "They might better not be called waves at
all, since they do not transport energy and momentum."
"Standing waves" is a misnomer, i.e. they don't stand
still and they do not meet the definition of "wave".

On another newsgroup, I pointed out the above
concept of EM waves just standing there is similar
to the idea that since the number of northbound
vehicles on the Golden Gate Bridge equal the number of
southbound vehicles, there is no net traffic flow and
therefore no maintenance of the bridge is required.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com