Consider the lowly photon ...

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12 years 9 months ago #11065 by Jim
Reply from was created by Jim
The intensity of a photon is related to it's area-right? Billions of photons per unit of area equals intensity of a beam of energy-right? The limits of intensity are unknown at this time. Maybe laser beams made by humans are beyond any intensity existing in nature anywhere in the universe. What is the current record for a laser intensity?

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12 years 8 months ago #13726 by shando
Replied by shando on topic Reply from Jim Shand
Viscosity = k * dE/dL k=constant; dE=change in kinetic energy; dL=change in length of path through fluid.

Assertation: The viscosity of the LCM is small but not-zero.

Evidence: LCM is entrained by large bodies such as planets. If the viscosity were zero there would be no entrainment.

Evidence: The energy of photons decreases in proportion to distance travelled. Although the velocity of the photon is maintained, the frequency of the photon is decreased as energy is shed due to the viscosity of the LCM. In other words, the red-shift is caused by distance travelled through the LCM, not because of universe expansion.

Evidence: Thus at some point (after travelling some billions of light years) the energy of the photon is exhausted, absorbed by the LCM. Otherwise, the sky would be aglow 24/7 due to the photons continuing to circulate throughout the universe, their paths deflected by gravity from large masses, forever.

Speculation: the zero-point-energy of "empty space" may be due to the accumulated energy from the exhausted photons.

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12 years 8 months ago #13727 by Larry Burford
(1) LB COMMENTS ADDED 03/06
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(4) LB COMMENTS ADDED 03/08

<b>[Shando]
<ul>
<li>A photon is a quantum of electro-magnetic energy (EM). </li>
<li>A photon is thought to be a disturbance in the light-carrying-medium (LCM).</li>
<li>Photons travel through the LCM at velocity c, the speed of light.</li>
</ul>
(1)
</b>Mathematically, EM energy can be treated as either a particle (quantum) or a wave. Which model you chose depends on what you are looking at and why you are looking at it. Some questions are easier to answer if you use the wave model, others are easier if you use the quantum model. Some questions can be answered with both modles. Some other questions can only be answered with one or the other.

Physically it is probably more accurate to think of EM energy as a wave.<b>
<ul>
<li>Photons are detected as waves (transverse waves?) in the LCM.</li>
<li>Photons are detected as particles (longitudinal waves in the LCM?).</li>
</ul>
(1)
</b>It is probably more accurate to say that EM energy (as transverse waves) propagates through the LCM. We never really "detect" them while they are traveling. The act of "detecting" EM energy terminates its travel through the universe. A detector can be very simple (a patch of dirt, or a dust particle floating in the air) or very sophisticated (a highly purified crystaline material with precise post-purification processing). However a detection event happens, the EM energy is destroyed (converted into something else - perhaps an electron with more energy than it previously had?).

I do not think any longtudinal wave phenomena associated with EM energy have been observed. I'm pretty sure there is no known theoretical reason preventing it, hovwever. In general waves travel as either transverse or longitudinal but not both.

One obvious exception is surface waves, which always propagate as an approximate 50-50 mixture of the transverse and longitudinal modes. But surface waves are rare in the universe, because they can only occur at a boundary (surface) between two differing media. We happen to live next to several such boundaries, so we tend to forget that surface waves are much less common than bulk waves.

I believe there is also some mixed mode behavior when waves are observed close (less than wavelength?) to their source.

Some media (the fluids, such as water or plasma) can only support longitudinal wave propagation. Other media (the solids) can support both longitudinal and transverse waves. The two modes propagate at different speeds in any given media.

And yes, this does mean that the LCM <u>must</u> behave like a solid. At least in some ways. I sure hope we can start detecting the particles soon. Studying elysium and elysions is going to produce some very cool physics.
<b>
<ul>
<li>The wave aspect of photons has a frequency, which is proportional to the energy of the photon.</li>
<li>Photons can be entangled in such a way that the determination of the state of one photon causes an instantaneous assumption of a predictable state by the related photon, regardless of its location. This implies a connection (in another dimension?) independent of 3D space.</li>
</ul>
(1)
</b>Maybe. Do not forget that any conclusion we reach is, <b>and must be</b>, theory (model) dependent. Most experiments involving quantum effects are based on statistical analysis. (It is very hard to isolate a single particle and then hold on to it long enough to do something to it.) A few single particle experiments have been done. But in general we process a large number of particles and make a lot of assumptions to get to an answer about one particle. This approach can and does produce useful information, but it also usually makes my BS detector nervous.


<b>
<ul>
<li>Is there a maximum limitation on photonic intensity (an upper limit on the photons per centimeter squared) at the point of emission?</li>
</ul>
(2)
</b>Not in terms fo the math, of course. (Math is cool in that way.) But physically there must be limits of some sort. Higher intensity means higher power, and at some point that power will be enough to melt or vaporize the matter involved in producing the EM energy. (The lens in a high energy laser system, for example.)

But vaporized matter can also be a source of EM energy, and if you collect enough in one spot (a star) the intensity moves upward dramatically. So we have a new limit to search for.

There has to be a limit, physically. The more intense a light beam is, the more you have to wiggle the particles of the particle field that the beam propagates within. Whatever it is that connects each particle to its neighbors will eventually be overwhelmed. Increasing inensity beyond this point probably cannot happen.

Hmm. It is possible that this "connection" between particles of the medium can be stronger in some places than in others. And that could lead to a beam of light that loses intensity in a non-linear way as it moves from a volume of relatvely high connection strength to a volume of relatively low strength.
<b>
<ul>
<li>Is there space between photons from the same source, far away from the source (the photonic intensity per cm^2 should decrease proportional to 1/4piR^2 where R is the distance from the source)?</li>
</ul>
(2)
</b>Once again, it is probably more realistic (more like physical reality) to think of EM energy as a wave propagating through a medim than as a particle traveling through that medium (or throuogh nothing).<b>
<ul>
<li>If a photon encounters opaque (for its frequency) matter, it may be reflected, or it may be absorbed, in which case it's energy is converted to some other form.</li>
</ul>
(2)
</b>Yes. This is what happens when we "detect" EM energy.

Indirect "detection" is also possible, but does not change the energy. You can arrange two or more beams of light so that they occupy the same volume of space at the same time, then go on to a physical detector for each beam. You are not actually "detecting" anything in this volume of space, but you do know that multiple beams of energy are present.

You can tell from the physical detections that occur later, and at different locations, that having occupied the same volume of space with other beams did not change any of the beams.

Beams made of actual particles (electrons, for example) that travel through space or through a medium do not behave this way. They break up when they hit each other. This is why particle colliders work.
<b>

<li>As the photon proceeds through space there is some non-zero loss of energy, probably due to friction within the LCM.</li>
<li>This change in energy is manifest as a change (reduction) in the frequency of the EM wave aspect of the photon over distance.</li>
<ul>
<li>How far will a photon travel (until its EM frequency becomes zero?)? This must be the fate of almost all the photons, however generated, within the universe.</li>
</ul>
(3)
</b>EM energy will probably lose all of its amplitude before it loses all of its freqency.

For a real world experiment, drop a pebble in still water and watch the surface waves expand outward. As they become too small to see they will still have essentially the same wavelength (frequency) they started with.

Keep in mind that surface waves are different from transverse waves, so EM waves might behave differently. If they do, the difference (for the context of this analogy) is probably small.
<b>
<ul>
<li>What happens to the energy contained in the photons that never encounter matter?</li>
<li>Answer: The energy of dead photons is obviously absorbed by the LCM. (Does the LCM consist of dead photons then?)</li>
</ul>
(2)
</b>The LCM - if it exists - comprises real, physical particles. That means these particles must have a volume and a mass. Photons, dead or alive, fail this test.

BTW, the LCM is not the only medium available for absorbing energy from EM waves.
<b>

<li>Is this the source of zero-point energy (ZPE)?</li>



<ul>
<li>Viscosity = k * dE/dL k=constant; dE=change in kinetic energy; dL=change in length of path through fluid.</li>

<li>Assertation: The viscosity of the LCM is small but not-zero.</li>
</ul>
(4)
</b>This easly works in the strict mathematical sense, as you have defined it here. Just keep in mind that in the physical sense this equation will have a wildly different meaning in the context of the LCM than, for example, in the context of air or ranch dressing.

We are still trying to work out an internally consistant set of physical properties for the LCM that will allow it to account for the observational and experimental data that mankind has collected to date.

(If such a set canot be found, then the concept of the LCM is probably falsified.)

Here is a very brief summary of our conclusions so far. Little attempt is made here to show supporting evidence.

<ul>
LCM has properties similar to a contained plasma:
<ul>
<li>each particle strongly repels all other particles</li>
<li>due to containment, the overall medium exists at some non-zero pressure</li>
<li>that pressue is probably very "high" (whatever that means in this context?)</li>
<li>this gives the medium a stiffness similar in some ways to that of a crystal</li>
</ul>
LCM has properties similar to a crystaline solid:
<ul>
<li>each particle is stationary relative to all of its neighbors</li>
<li>if we extrapolate from wave-speed-versus-stiffness for solids made from normal sized matter, the stiffness needed by the LCM to propagate waves at 300,000 km/sec is about 10^5 times the stiffness of steel</li>
<li>under some conditions neighborhoods can move relative to neighborhoods</li>
<li>The boundary zones between such neighborhoods might produce detectable anomalies in EM waves that have passed through them</li>
</ul>
LCM has other properties:
<ul>
<li>The particles do not combine into molecule-like structures</li>
<li>The particles are small enough to penetrate normal sized matter</li>
<li>The particles are never in direct contact - typical center to center separation is likely to be several thousand particle diameters, but could be much more</li>
<li>TBD</li>
</ul>
</ul>

<b>

<li>Evidence: LCM is entrained by large bodies such as planets. If the viscosity were zero there would be no entrainment.</li>

<li>Evidence: The energy of photons decreases in proportion to distance travelled. Although the velocity of the photon is maintained, the frequency of the photon is decreased as energy is shed due to the viscosity of the LCM. In other words, the red-shift is caused by distance travelled through the LCM, not because of universe expansion.</li>

<li>Evidence: Thus at some point (after travelling some billions of light years) the energy of the photon is exhausted, absorbed by the LCM. Otherwise, the sky would be aglow 24/7 due to the photons continuing to circulate throughout the universe, their paths deflected by gravity from large masses, forever.</li>

<li>Speculation: the zero-point-energy of "empty space" may be due to the accumulated energy from the exhausted photons.</li></b>

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12 years 8 months ago #21338 by shando
Replied by shando on topic Reply from Jim Shand
&gt;&gt; Some media (the fluids, such as water or plasma) can only support longitudinal wave propagation.

Hmmm ... what about sound waves conducted through water? The sound of a rock hitting the water travels about 1,484 m/s (15 deg C) in the water, far quicker than the speed of the surface waves will spread out. The surface wave is a transverse wave, yes?

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12 years 8 months ago #13728 by Larry Burford
Sounds about right. Sound is a longitudinal wave in the bulk of the medium. In general it does propagate at a different speed than surface waves.

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12 years 8 months ago #24408 by Jim
Replied by Jim on topic Reply from
The above comments about photons clearly show the confusion Plank's bundle and the photon have always generated. We have a defined and well documented unit I think makes sense to call a photon. And we have a huge and undefined bundle of photons given in Plank's work derived from earlier work. I don't see how you progress with any good model until at least these two details are cleared up.

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