Cecil Moore wrote:

You didn't answer my simple question on another
thread.

I don't want to get in another silly fight with you, Cecil. I'm
evacuated from my house right now, and don't have a lot of patience to
expend.

The question is: Can interference occur
in free space devoid of any of your required
physical objects?

Not from one source of light without any physical objects to act as a
reflecting surface.

73, ac6xg

Jim Kelley wrote:
I'm evacuated from my house right now,
and don't have a lot of patience to expend.

I assume that is the result of the fire storm out
there in CA. The whole nation is praying for you guys.
When does the wet season start?

Not from one source of light without any physical objects to act as a
reflecting surface.

Can the physical objects be outside of the cubic
meter of space that is under consideration? If so,
I misunderstood your earlier posting. (If you say
"yes" they could be light-years outside the cubic
meter under consideration.)
--
73, Cecil http://www.w5dxp.com

Cecil Moore wrote:

Jim Kelley wrote:

I'm evacuated from my house right now,
and don't have a lot of patience to expend.


I assume that is the result of the fire storm out
there in CA. The whole nation is praying for you guys.
When does the wet season start?

Generally, never. We had 3 inches of rain last year. Soon though,
Diane Feinstein and Barbara Boxer will introduce punitive legislation
making it more difficult for people to live in (arid regions of)
Southern California - ostensibly to save Snail Darters in the
Sacramento delta. It's a kind of inedible fish I think.

Not from one source of light without any physical objects to act as a
reflecting surface.


Can the physical objects be outside of the cubic
meter of space that is under consideration? If so,
I misunderstood your earlier posting. (If you say
"yes" they could be light-years outside the cubic
meter under consideration.)

I don't think it matters where it is, or how much space is involved.
For a single source to create an interferernce pattern, there must be
a reflector somewhere. An antenna tuner for example. Interference is
the result of the overlap of waves.

73, ac6xg

Jim Kelley wrote in news:fg8c3e$kbc$1
@news.service.uci.edu:

I don't think it matters where it is, or how much space is involved.
For a single source to create an interferernce pattern, there must be
a reflector somewhere. An antenna tuner for example. Interference is
the result of the overlap of waves.

Jim, could a diffractor or refractor provide the physical device that might
lead to interference?

Owen

Owen Duffy wrote:
Jim Kelley wrote in news:fg8c3e$kbc$1
@news.service.uci.edu:


I don't think it matters where it is, or how much space is involved.
For a single source to create an interferernce pattern, there must be
a reflector somewhere. An antenna tuner for example. Interference is
the result of the overlap of waves.


Jim, could a diffractor or refractor provide the physical device that might
lead to interference?

Owen

I'm am almost certain that you already know the answer to that
question, so I'm left to wonder why you are asking it.

Jim

Jim Kelley wrote in
:



Owen Duffy wrote:
Jim Kelley wrote in news:fg8c3e$kbc$1
@news.service.uci.edu:


I don't think it matters where it is, or how much space is involved.
For a single source to create an interferernce pattern, there must be
a reflector somewhere. An antenna tuner for example. Interference
is the result of the overlap of waves.


Jim, could a diffractor or refractor provide the physical device that
might lead to interference?

Owen

I'm am almost certain that you already know the answer to that
question, so I'm left to wonder why you are asking it.

No, I am not certain, and in the interest of learning from you I am
questioning the generality of whether a reflector is the only means of
creating interference from a single source.

Owen

Stefan Wolfe wrote:
I see no other means this energy can be
imparted other then via electrons (ON AVERAGE) exchanging orbital states in
the antenna copper (etc.) atoms resulting in a release of this total energy
per photon. How can photons otherwise be manufactured by passing an analog
wavelike-field forcing function through another field?

Above you are referring to tight-binding electrons. But
Our RF antennas make use of *free electrons* which are
thought to exist in the outer orbits of conductors.
Instead of changing orbits within a single atom, these
free electrons jump from atom to atom and from groups
of atoms to other groups of atoms. When a free electron
emits a photon, it is not associated with an orbit
change and so is not quantized to any orbit change. The
photon is instead quantized to the frequency of the
energy source and is therefore coherent with that source
which is our RF transmitters.
--
73, Cecil http://www.w5dxp.com

Jim Kelley wrote:
I don't think it matters where it is, or how much space is involved. For
a single source to create an interferernce pattern, there must be a
reflector somewhere. An antenna tuner for example. Interference is the
result of the overlap of waves.

Do you consider a dipole in free space to be
a "single source"? There is no reflector yet
there is plenty of interference.
--
73, Cecil http://www.w5dxp.com

"Cecil Moore" wrote in message
. net...
H. Adam Stevens wrote:
"coherent photons" It's a laser? Cool.

Surprise! Our $100 RF transmitters emit coherent photons just
like a $100,000 laser. Maybe we should call them RASERs. :-)
Do you remember MASERs?
--
73, Cecil http://www.w5dxp.com

"transmitters emit coherent photons "

Sure Cecil.

And the laser pointer I use was a bit less expensive.

MASER: Microwave Amplification by Stimulated Emission of Radiation

"The fundamental physical principle motivating the MASER is the concept of
stimulated emission, first introduced by Einstein in 1917. Before defining
it we look at two related but more familiar phenomena involving the
interplay between matter and radiation, absorption and spontaneous
emission."
http://einstein.stanford.edu/content/faqs/maser.html

"MASER. In each frame, a molecule in the upper level of the MASER transition
(that is, in the high energy, excited state) is indicated by a large red
circle, while one in the lower level (low energy state) is indicated by a
small blue circle. (a) All of the molecules are in the upper state and a
photon of wavelength l (shown in green) is incident from the left. (b) The
photon l stimulates emission from the first molecule, so there are now two
photons of wavelength l, in phase. (c) These photons stimulate emission from
the next two molecules, resulting in four photons of wavelength l. (d) The
process continues with another doubling of the number of photons."

Stimulated Emission of Radiation is a quantum mechanical effect that has
exactly zero to do with HF radio.
For microwaves we use molecules, for light we use atoms.

73
H.
NQ5H


"Waves of average nausea" is more like it.

Owen Duffy wrote:
Jim Kelley wrote in
:



Owen Duffy wrote:

Jim Kelley wrote in news:fg8c3e$kbc$1
:



I don't think it matters where it is, or how much space is involved.
For a single source to create an interferernce pattern, there must be
a reflector somewhere. An antenna tuner for example. Interference
is the result of the overlap of waves.


Jim, could a diffractor or refractor provide the physical device that
might lead to interference?

Owen

I am almost certain that you already know the answer to that
question, so I'm left to wonder why you are asking it.


No, I am not certain, and in the interest of learning from you I am
questioning the generality of whether a reflector is the only means of
creating interference from a single source.

Owen

Fair enough, Owen. The easiest way I can think of to demonstate
interference of light is with a laser and a pair of narrow, closely
spaced slits. A diffration grating is essentially an array of
slit-like reflectors that generates a more complex type of
interference pattern. You could use one of the internal surfaces of a
prism (refractor) as a reflector. Partially reflective beam splitters
or mirrors are often used in interfereometers. And there are of
course methods by which to create sonic interference. The simplest
way is to wire a pair of stereo speakers out of phase and observe the
frequency dependent phase cancellation effect by listening to music at
different positions and speaker separations.

There are any number of possible ways to generate interference
phenomena, all of which utilize real physical objects to redirect
radiation. It is the real physical objects used to create the
interference pattern that redirect energy.

73, ac6xg