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Question about "Another look at reflections" article.
"K1TTT" wrote ... On May 30, 5:05 pm, "Szczepan Bialek" wrote: In schools are all theories. the only purpose for disproved theories in schools is for historical context. sometimes it is useful to show students what doesn't work so they don't waste time repeating past mistakes. aether theories are one that is taught and then demonstrated in class as incorrect. once the student makes the measurements they get a better feeling why aethers are bogus. Up to now we have agreed that Maxwell/Lorents aether is bogus and that in the space is the plasma (ions and electrons) and the dust. They rotate with the Sun in the form of a whirl. You are the first radioman who admit this. S* |
Question about "Another look at reflections" article.
On May 31, 12:34*pm, K1TTT wrote:
what does happen to that last photon in the infinite series of smaller and smaller reflections between discontinuities?? It doesn't matter. At HF wavelengths, the last photon is not going to have an appreciable effect ( but maybe at gamma-ray wavelengths). The collapse of the probability function indicates that if one runs a large number of trials, n% of those very last photons will be reflected and (100-n%) of them will be absorbed. That probability function has never been proven to be wrong. I have no idea why an otherwise knowledgeable individual could be argumentative concerning this subject. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On May 31, 12:58*pm, "Szczepan Bialek" wrote:
You are the first radioman who admit this. What does the fact that particles with rest mass are spiraling away from the sun have to do with photons that propagate in (almost) a straight line away from the sun? The only effect that the sun has on photons emitted by the sun is to slow them down. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On May 31, 5:58*pm, "Szczepan Bialek" wrote:
*"K1TTT" ... On May 30, 5:05 pm, "Szczepan Bialek" wrote: *In schools are all theories. the only purpose for disproved theories in schools is for historical context. *sometimes it is useful to show students what doesn't work so they don't waste time repeating past mistakes. *aether theories are one that is taught and then demonstrated in class as incorrect. *once the student makes the measurements they get a better feeling why aethers are bogus. Up to now we have agreed that Maxwell/Lorents aether is bogus and that in the space is the plasma (ions and electrons) and the dust. They rotate with the Sun in the form of a whirl. You are the first radioman who admit this. S* the solar wind is well know and easily studies with the satellite data available today. but it is not an aether, the interplanetary plasma does not propagate the light from the sun, it just gets in the way. |
Question about "Another look at reflections" article.
On May 31, 6:05*pm, Cecil Moore wrote:
On May 31, 12:34*pm, K1TTT wrote: what does happen to that last photon in the infinite series of smaller and smaller reflections between discontinuities?? It doesn't matter. At HF wavelengths, the last photon is not going to have an appreciable effect ( but maybe at gamma-ray wavelengths). The collapse of the probability function indicates that if one runs a large number of trials, n% of those very last photons will be reflected and (100-n%) of them will be absorbed. That probability function has never been proven to be wrong. I have no idea why an otherwise knowledgeable individual could be argumentative concerning this subject. -- 73, Cecil, w5dxp.com i hate mechanical analogies, they lead to too many misconceptions. the last photon question was meant to be rhetorical. |
Question about "Another look at reflections" article.
On 25 mayo, 03:35, Richard Clark wrote:
On Mon, 24 May 2010 17:17:41 -0700 (PDT), lu6etj wrote: PSE, with the due respect and consideration toward you an the distinguished colleagues and friends, Would you mind return to the original question? (sorry if it is not this the most polite form to ask it) Hi Miguel, I presume by "original question" you mean: On Mon, 24 May 2010 13:06:19 -0700 (PDT), lu6etj wrote: żAbsorb the reflected power or amortiguate the effects of variyng load impedance? The answer is YES. Now, if you mean by absorb that all absorbtion results in heat, then the answer is NO. If you mean by absorb that all energy is combined in a load, then the answer is YES. The difference between YES and NO is the PHASE differences of the two energies that are combined. 73's Richard Clark, KB7QHC Hi all First the first: Sorry Szczepan, do not feel upset I wanted to say "Me" don't go off topic with my own answers, not you. Very interesting comments! I think we must agree on meaning of words and basement concepts employed to discuss these matters, otherwise we end up talking about different "things" (Babel curse what confuses our tongues). If we do not agree with meaning of, for example, "interaction", how can we reach an agreement on much more complex things that depend on this word/concept? This is not a criticism to anyone, is only my point of view about what I think is a partial source of apparently irreductible positions in the group. I believe Richard, K1TTT and me, have sinchronized minds about "Interaction" word/concept meaning. I suppose must be a more deep underlying assumptios that make it possible. However I believe I understand the "idea" underlying Cecil concept about "interaction" and I believe I can "see" his point, To me, Cecil's interaction concept it is a very common idea, I do not think Cecil be a "hard to die" man :) I think we have to do our more honest efforts to sinchronize ideas. I do not want to go off topic, but let me bring a couple of thinkings to the table (they are not mine). * Students come into our classrooms with an established world-view, formed by years of prior experience and learning. * Even as it evolves, a student's world-view filters all experiences and affects their interpretation of observations. * Students are emotionally attached to their world-views and will not give up their world-views easily. * Challenging, revising, and restructuring one's world-view requires much effort. (from http://srri.umass.edu/topics/constructivism) Why these above things would not happen to me? ...... Returning: Cecil, given A+B=C, do you you see C as result of an interaction (or mutual action) among A and B, or C a simply result of A added to B? Another question to clarify my undestanding of your propositions: do you see waves interacting themselves in a discontinuity, or you see them interacting with the discontinuity? or both phenomena at the same time?. Change discontinuity for load and please tell me. Richard, you said: -"Because" leads to superstition-; you are pointing to causal relations? I believe was you who said dislike representations, if it is yes, were you aiming to create mental images of physical phenomena? Here we often use the word "methafor" in figured sense instead "analogy", for example, "my car it is as strong as a locomotive" it is a true methaphor. In metaphor, there are two levels or terms: the real (my car) and evoked or imaginary (locomotive). Coulored water is it a true methaphor or an analogy? Simple analogies as useful things until one (or more) of they not work... then, ciao analogy..!, not so bad :), however... notice!, our ideas are not equal to the "out there" world. Concepts, models, (mathematical models also, of course)... are not they our mind's "analogies" "out there" sensorial/injstrumental perceived world? These are not trivial epistemology issues, our "observer" leads directly to the question about "Is the moon there when nobody looks?" (N. D.Mermin). When we go out of our classic-simplistic- realistic-traditional ham world... "we are in troubles, Houston", slippery soil!, I make the sign of the cross! :) K1TTT said: -Standing waves are a figment of your instrumentation-. My dictionary translates "figment" as "product" or "chimera", please, tell me what word should I use to correctly read the sentence? 73 Miguel Ghezzi - LU6ETJ |
Question about "Another look at reflections" article.
"lu6etj" wrote ... Here we often use the word "methafor" in figured sense instead "analogy", for example, "my car it is as strong as a locomotive" it is a true methaphor. In metaphor, there are two levels or terms: the real (my car) and evoked or imaginary (locomotive). Coulored water is it a true methaphor or an analogy? Simple analogies as useful things until one (or more) of they not work... then, ciao analogy..!, Radio waves and sound are in full analogy. K1TTT said: -Standing waves are a figment of your instrumentation-. My dictionary translates "figment" as "product" or "chimera", please, tell me what word should I use to correctly read the sentence? Waves always travel (pressure or voltage pulses). If the wave interact with the reflected one than the places where the pressures/voltages change are standing. The reflected wave cam be weaker if the mirror is partialy transparent (or if an absorbtion take place). S* 73 Miguel Ghezzi - LU6ETJ |
Question about "Another look at reflections" article.
"K1TTT" wrote ... On May 31, 5:58 pm, "Szczepan Bialek" wrote: Up to now we have agreed that Maxwell/Lorents aether is bogus and that in the space is the plasma (ions and electrons) and the dust. They rotate with the Sun in the form of a whirl. You are the first radioman who admit this. the solar wind is well know and easily studies with the satellite data available today. but it is not an aether, The aether in sense of medium for light propagation. the interplanetary plasma does not propagate the light from the sun, In the interstellar medium (ISM) are ions, electrons and dust. http://www.astronomynotes.com/ismnotes/s2.htm The medium are the electrons ony. The rest are contaminations, like the fog and dust in the air for the sound waves. Do you see any sensible another solution? S* |
Question about "Another look at reflections" article.
On May 31, 4:36*pm, K1TTT wrote:
i hate mechanical analogies, they lead to too many misconceptions. the last photon question was meant to be rhetorical. I apologize for not recognizing that. Words don't always convey the intended context. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 1, 5:52*am, lu6etj wrote:
On 25 mayo, 03:35, Richard Clark wrote: On Mon, 24 May 2010 17:17:41 -0700 (PDT), lu6etj wrote: PSE, with the due respect and consideration toward you an the distinguished colleagues and friends, Would you mind return to the original question? (sorry if it is not this the most polite form to ask it) Hi Miguel, I presume by "original question" you mean: On Mon, 24 May 2010 13:06:19 -0700 (PDT), lu6etj wrote: żAbsorb the reflected power or amortiguate the effects of variyng load impedance? The answer is YES. Now, if you mean by absorb that all absorbtion results in heat, then the answer is NO. If you mean by absorb that all energy is combined in a load, then the answer is YES. The difference between YES and NO is the PHASE differences of the two energies that are combined. 73's Richard Clark, KB7QHC Hi all First the first: Sorry Szczepan, do not feel upset *I wanted to say "Me" don't go off topic with my own answers, not you. Very interesting comments! I think we must agree on meaning of words and basement concepts employed to discuss these matters, otherwise we end up talking about different "things" (Babel curse what confuses our tongues). If we do not agree with meaning of, for example, "interaction", how can we reach an agreement on much more complex things that depend on this word/concept? This is not a criticism to anyone, is only my point of view about what I think is a partial source of apparently irreductible positions in the group. I believe Richard, K1TTT and me, have sinchronized minds about "Interaction" word/concept meaning. I suppose must be a more deep underlying assumptios that make it possible. However I believe I understand the "idea" underlying Cecil concept about "interaction" and I believe I can "see" his point, To me, Cecil's interaction concept it is a very common idea, I do not think Cecil be a "hard to die" man :) I think we have to do our more honest efforts to sinchronize ideas. I do not want to go off topic, but let me bring a couple of thinkings to the table (they are not mine). * Students come into our classrooms with an established world-view, formed by years of prior experience and learning. * Even as it evolves, a student's world-view filters all experiences and affects their interpretation of observations. * Students are emotionally attached to their world-views and will not give up their world-views easily. * Challenging, revising, and restructuring one's world-view requires much effort. (fromhttp://srri.umass.edu/topics/constructivism) Why these above things would not happen to me? ..... Returning: Cecil, given A+B=C, do you you see C as result of an interaction (or mutual action) among A and B, or C a simply result of A added to B? Another question to clarify my undestanding of your propositions: do you see waves interacting themselves in a discontinuity, or you see them interacting with the discontinuity? or both phenomena at the same time?. Change discontinuity for load and please tell me. Richard, you said: -"Because" leads to superstition-; you are pointing to causal relations? I believe was you who said dislike representations, if it is yes, were you aiming to create mental images of physical phenomena? Here we often use the word "methafor" in figured sense instead "analogy", for example, "my car it is as strong as a locomotive" it is a true methaphor. In metaphor, there are two levels or terms: the real (my car) and evoked or imaginary (locomotive). Coulored water is it a true methaphor or an analogy? Simple analogies as useful things until one (or more) of they not work... then, ciao analogy..!, not so bad :), however... notice!, our ideas are not equal to the "out there" world. Concepts, models, (mathematical models also, of course)... are not they our mind's "analogies" "out there" sensorial/injstrumental perceived world? These are not trivial epistemology issues, our "observer" leads directly to the question about "Is the moon there when nobody looks?" (N. D.Mermin). When we go out of our classic-simplistic- realistic-traditional ham world... "we are in troubles, Houston", slippery soil!, I make the sign of the cross! :) K1TTT said: -Standing waves are a figment of your instrumentation-. My dictionary translates "figment" as "product" or "chimera", please, tell me what word should I use to correctly read the sentence? 73 Miguel Ghezzi - LU6ETJ in this context figment=product. often used to describe something that is a result of an over active imagination. the only reason you can see standing waves is because a measurement or observation makes them look like they are 'standing' when it is really the interaction of two or more regular traveling waves. |
Question about "Another look at reflections" article.
On Jun 1, 8:42*am, "Szczepan Bialek" wrote:
*"K1TTT" ... On May 31, 5:58 pm, "Szczepan Bialek" wrote: Up to now we have agreed that Maxwell/Lorents aether is bogus and that in the space is the plasma (ions and electrons) and the dust. They rotate with the Sun in the form of a whirl. You are the first radioman who admit this. the solar wind is well know and easily studies with the satellite data available today. *but it is not an aether, The aether in sense of medium for light propagation. the interplanetary plasma does not propagate the light from the sun, In the interstellar medium (ISM) are ions, electrons and dust.http://www.astronomynotes.com/ismnotes/s2.htm The medium are the electrons ony. The rest are contaminations, like the fog and dust in the air for the sound waves. Do you see any sensible another solution? S* the electrons can not do it either. there are not enough of them and they move too slowly in the plasma to propagate light. these are easily measured, you can watch the density directly using the ace satellite web page and calculate the speed of longitudinal waves if you want, but it won't be anywhere near light speed. |
Question about "Another look at reflections" article.
On Jun 1, 12:52*am, lu6etj wrote:
Returning: Cecil, given A+B=C, do you you see C as result of an interaction (or mutual action) among A and B, or C a simply result of A added to B? Of course, there are all types of "addition", e.g. arithmetic, algebraic, voltage phasor, Poynting vector, scalar power, superposition, merging, mixing, ... Which type of "addition" is appropriate depends upon the nature of what is being added. Simply put, if A + B = C creates an irreversible result, then A has (obviously?) interacted with B. If the result is reversible, then A has not interacted with B. For the great majority of cases, superposition does not result in interaction. For the great majority of cases, interference does not result in interaction. For some (special?) cases, superposition (plus associated interference and wave cancellation) results in interaction and the result is irreversible. Non reflective glass is an example of wave interaction. The internal reflection cancels the external reflection and the energy in those two reflections changes directions. A Z0-match at an impedance discontinuity in an RF transmission line is another example. Again, if two waves are coherent, collimated, and traveling in the same direction, those two waves will interact, i.e. their superposition result is not reversible. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 1, 3:42*am, "Szczepan Bialek" wrote:
Do you see any sensible another solution? What about the "quantum soup", particles winking in and out of existence throughout space? How do you explain the Casimir effect? How do you explain the flow of photons through evacuated space that is devoid of electrons? -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 1, 11:23*am, Cecil Moore wrote:
On Jun 1, 12:52*am, lu6etj wrote: Returning: Cecil, given A+B=C, do you you see C as result of an interaction (or mutual action) among A and B, or C a simply result of A added to B? Of course, there are all types of "addition", e.g. arithmetic, algebraic, voltage phasor, Poynting vector, scalar power, superposition, merging, mixing, ... Which type of "addition" is appropriate depends upon the nature of what is being added. Simply put, if A + B = C creates an irreversible result, then A has (obviously?) interacted with B. If the result is reversible, then A has not interacted with B. For the great majority of cases, superposition does not result in interaction. For the great majority of cases, interference does not result in interaction. For some (special?) cases, superposition (plus associated interference and wave cancellation) results in interaction and the result is irreversible. Non reflective glass is an example of wave interaction. The internal reflection cancels the external reflection and the energy in those two reflections changes directions. A Z0-match at an impedance discontinuity in an RF transmission line is another example. Again, if two waves are coherent, collimated, and traveling in the same direction, those two waves will interact, i.e. their superposition result is not reversible. -- 73, Cecil, w5dxp.com what exactly is the 'interaction' and why is it unique to that special coherent, collimated, etc, case? if two waves can 'interact' in that case there should be other evidence that they can interact in other situations. just because a+b=c doesn't mean that a and b have magically disappeared for some reason, in mathematics c=a+b is just as valid and implies that c is made up of a and b... or using your water analogy, adding one pint to another pint doesn't magically cause them to 'interact' in some way, the original water is still there, perhaps indistinguishable from each other, but still there. it may be convenient to represent the result of summing an infinite series of reflections as a single number, but it is not necessary. |
Question about "Another look at reflections" article.
On Jun 1, 8:10*am, K1TTT wrote:
what exactly is the 'interaction' *and why is it unique to that special coherent, collimated, etc, case? Is it not obvious that when two reflected waves cancel in one direction, as at the surface of a 1/4WL thin-film coating on glass, and their combined EM energy is redistributed in the opposite direction, that those two waves have interacted, i.e. have suffered a permanent change and have lost their original identities? Is it not obvious that when two waves are traveling two different paths where the incident angle is, e.g. two degrees, that those two waves will superpose and interfere throughout a certain space after which they emerge intact, unaffected, and have obviously not interacted, i.e. they suffered no permanent change and have maintained their original identities? Did superposition occur in both cases? Yes. Did interference occur in both cases? Yes. Did wave cancellation occur in both cases? No, just in the non-reflective glass case. Consider a transmission line with an SWR of 5.83:1. The sourced power is 100 watts. The forward power is 200 watts. The reflected power is 100 watts. All of the reflected power is redistributed back toward the load at a Z0-match through reflection and wave cancellation. Zero reflected power is incident upon the source. Does the 100w source wave lose its identity when it merges with the 100w of redistributed reflected wave to become the 200w forward wave? Is the steady-state load energy coming from the source wave or the redistributed reflected wave or both? Seems to me, it is obvious that the two original component waves have interacted and lost their original identities for good if they are pure coherent sine waves traveling in the same direction confined to a coaxial transmission line. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Mon, 31 May 2010 22:52:35 -0700 (PDT), lu6etj
wrote: Richard, you said: -"Because" leads to superstition-; you are pointing to causal relations? Hi Miguel, Language would have us believe that causal relations "be" from "cause." Common language sometimes uses "because" as a bridge between phrases without necessarily implying causality - in other words, the word "because" is verbal noise when that happens. "Because" is often a one word reply to a child's question "Why?" I believe was you who said dislike representations, if it is yes, were you aiming to create mental images of physical phenomena? Oh, I do that all the time. However, I do not mistake representations as being the real thing. In other contexts, they are more real than the real thing. So, if there is dislike, it comes from seeing inferior representation when better work requires so little more effort. Here we often use the word "methafor" now there's a curious and suggestive spelling in figured sense instead "analogy", for example, "my car it is as strong as a locomotive" it is a true methaphor. In metaphor, there are two levels or terms: the real (my car) and evoked or imaginary (locomotive). Coulored water is it a true methaphor or an analogy? Both. But context should resolve that, or it could still be both. That is why metaphor and analogy are so dangerous. That is also why it is so useful in fiction. We get enough fiction here. Simple analogies as useful things until one (or more) of they not work... then, ciao analogy..!, not so bad :), however... notice!, our ideas are not equal to the "out there" world. Concepts, models, (mathematical models also, of course)... are not they our mind's "analogies" "out there" sensorial/injstrumental perceived world? These are not trivial epistemology issues, our "observer" leads directly to the question about "Is the moon there when nobody looks?" (N. D.Mermin). When we go out of our classic-simplistic- realistic-traditional ham world... "we are in troubles, Houston", slippery soil!, I make the sign of the cross! :) Namaste. 73's Richard Clark, KB7QHC |
Question about "Another look at reflections" article.
3. character assignation.
Hi Miguel, How well does this translate to Spanish? As I've offered, native speakers are often the poorest communicators in their own language. Imagine trying to visualize an optical metaphor when this comet hits the windshield. 73's Richard Clark, KB7QHC |
Question about "Another look at reflections" article.
On Jun 1, 1:52*pm, Cecil Moore wrote:
On Jun 1, 8:10*am, K1TTT wrote: what exactly is the 'interaction' *and why is it unique to that special coherent, collimated, etc, case? Is it not obvious that when two reflected waves cancel in one direction, as at the surface of a 1/4WL thin-film coating on glass, and their combined EM energy is redistributed in the opposite direction, that those two waves have interacted, i.e. have suffered a permanent change and have lost their original identities? Is it not obvious that when two waves are traveling two different paths where the incident angle is, e.g. two degrees, that those two waves will superpose and interfere throughout a certain space after which they emerge intact, unaffected, and have obviously not interacted, i.e. they suffered no permanent change and have maintained their original identities? no, it is not obvious. where do you draw the line... 1 degree, .1 degree, .001 degree? at what point is the angle small enough to say that they have 'interacted' and the energy is redistributed? Did superposition occur in both cases? Yes. Did interference occur in both cases? Yes. Did wave cancellation occur in both cases? No, just in the non-reflective glass case. i propose that 'cancellation' is just a special case of interference where the waves are 'close enough' to collinear that you never see the interference pattern. this would of course always apply in a transmission line because they are confined. closely analyze the transient response of your non-reflective glass in the case where the wave is not incident perpendicular to the glass. do each reflection from each interface separately as the wave travels in the coating at an angle. then reduce the angle to very near perpendicular and you should see that there are indeed reflections that should very nearly 'cancel' each other out as the number of reflections gets bigger. |
Question about "Another look at reflections" article.
On Tue, 1 Jun 2010 13:41:03 -0700 (PDT), lu6etj
wrote: Richard: OK to "representations". Do you think there are things accesible (or "visible") to our intelect (objectivism) or all we have are models of external world built by our minds with the help and mediation of our biological and technical sensing/measurements apparatus? Hi Miguel, This has gotten pretty metaphysical. I insist in that because I think that two or more models could be capable to "explain" observed phenomena and we could partially agree on they instead dispute hard about the "right one" :) Data explains - the rest is the ego of pride of authorship. Metaphysical discussions about the "thing itself" was very strong and sterile before Newton stop caring about the "whys" and decided dealts with "howtos" :). I think you were thinking about this when you equalize "because"="superstition". Am I right? I don't know. However, though causality is an epistemological issue, usually in the macroscopic phenomena we accept "If A, then B" as a causal relation, example: If a rock hits my feet I absolutelly think the pain is due to the stone, not a simple acausal correlation. In this sense is it valid to use "because the stone")? Thanks to all for your comments Don't you think your pain is due to nerve sensations? Rocks hit rocks all the time and there is no pain due to anything any where. Or maybe there is an optical proof that refutes this. 73's Richard Clark, KB7QHC |
Question about "Another look at reflections" article.
On Jun 1, 3:41*pm, lu6etj wrote:
the only reason you can see standing waves is because a measurement or observation makes them look like they are 'standing' when it is really the interaction of two or more regular traveling waves. If I do not bad understand your response to Cecil, In your sentence I would change "interaction" by "manifestation". What do you think? I don't remember writing that, Miguel. If I did write that, then I misused the word "interaction". I wrote elsewhere that forward and reflected waves don't interact as long as Z0 stays constant. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 1, 5:44*pm, K1TTT wrote:
no, it is not obvious. *where do you draw the line... 1 degree, .1 degree, .001 degree? *at what point is the angle small enough to say that they have 'interacted' and the energy is redistributed? I don't know the answer but zero degrees (perfect collimation) will result in interaction. i propose that 'cancellation' is just a special case of interference where the waves are 'close enough' to collinear that you never see the interference pattern. When b1 = s11*a1 + s12*a2 = 0 at an impedance discontinuity, wave cancellation has taken place. s11*a1 and s12*a2 are coherent sine waves, equal in magnitude, and 180 degrees out of phase. Have you read the FSU web page where they describe wave cancellation? All these concepts are old hat to optical physicists. micro.magnet.fsu.edu/primer/java/scienceopticsu/interference/ waveinteractions/index.html "... when two waves of equal amplitude and wavelength that are 180- degrees ... out of phase with each other meet, they are not actually annihilated, ... All of the photon energy present in these waves must somehow be recovered or redistributed in a new direction, according to the law of energy conservation ... Instead, upon meeting, the photons are redistributed to regions that permit constructive interference, so the effect should be considered as a redistribution of light waves and photon energy rather than the spontaneous construction or destruction of light." -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 1, 11:31*pm, Cecil Moore wrote:
"... All of the photon energy present in these waves must I suggest that you immediately dump any reference that includes a phrase like "photon energy present in a wave". There is a wave theory of light, and there is a particle theory of light, and these two theories do not play well together. 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. ....Keith |
Question about "Another look at reflections" article.
On Jun 2, 3:31*am, Cecil Moore wrote:
On Jun 1, 5:44*pm, K1TTT wrote: no, it is not obvious. *where do you draw the line... 1 degree, .1 degree, .001 degree? *at what point is the angle small enough to say that they have 'interacted' and the energy is redistributed? I don't know the answer but zero degrees (perfect collimation) will result in interaction. what is the physical mechanism for 'interaction' that requires perfect collimation? i propose that 'cancellation' is just a special case of interference where the waves are 'close enough' to collinear that you never see the interference pattern. When b1 = s11*a1 + s12*a2 = 0 at an impedance discontinuity, wave cancellation has taken place. s11*a1 and s12*a2 are coherent sine waves, equal in magnitude, and 180 degrees out of phase. Have you read the FSU web page where they describe wave cancellation? All these concepts are old hat to optical physicists. micro.magnet.fsu.edu/primer/java/scienceopticsu/interference/ waveinteractions/index.html "... when two waves of equal amplitude and wavelength that are 180- degrees ... out of phase with each other meet, they are not actually annihilated, ... All of the photon energy present in these waves must somehow be recovered or redistributed in a new direction, according to the law of energy conservation ... Instead, upon meeting, the photons are redistributed to regions that permit constructive interference, so the effect should be considered as a redistribution of light waves and photon energy rather than the spontaneous construction or destruction of light." -- 73, Cecil, w5dxp.com coming from a 'primer' and containing words like 'somehow' doesn't raise my confidence in the explanation. |
Question about "Another look at reflections" article.
On Jun 2, 10:33*am, Keith Dysart wrote:
On Jun 1, 11:31*pm, Cecil Moore wrote: "... All of the photon energy present in these waves must I suggest that you immediately dump any reference that includes a phrase like "photon energy present in a wave". There is a wave theory of light, and there is a particle theory of light, and these two theories do not play well together. 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. ...Keith agreed. photons are good when working with other elementary particle interactions to represent the em energy lost or transferred during particle interactions. they are not that useful when studying wave propagation or interaction with macroscopic object... including 1/4 wave coatings. |
Question about "Another look at reflections" article.
On Jun 2, 6:39*am, K1TTT wrote:
On Jun 2, 10:33*am, Keith Dysart wrote: On Jun 1, 11:31*pm, Cecil Moore wrote: "... All of the photon energy present in these waves must I suggest that you immediately dump any reference that includes a phrase like "photon energy present in a wave". There is a wave theory of light, and there is a particle theory of light, and these two theories do not play well together. 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. ...Keith agreed. *photons are good when working with other elementary particle interactions to represent the em energy lost or transferred during particle interactions. *they are not that useful when studying wave propagation or interaction with macroscopic object... including 1/4 wave coatings. For those who may be interested, Richard Feynman offers an introductory lecture on photons he http://vega.org.uk/video/subseries/8 It illustrates that attempting to compute 1/4 wave coating behaviour with photons would be extremely tedious, though possible. On the other hand, at low light levels, where individual photons become discrete events, the wave theory becomes completely inadequate. Fortunately, for practical applications, power levels are much higher than this and the wave aproach is quite useful. ....Keith |
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 |
Question about "Another look at reflections" article.
On Jun 2, 5:37*am, K1TTT wrote:
what is the physical mechanism for 'interaction' that requires perfect collimation? The impossibility of divergence. That collapsed probability function can occur in an RF transmission line and in an interferometer. Secondary effects, e.g. noise, are obviously ignored. coming from a 'primer' and containing words like 'somehow' doesn't raise my confidence in the explanation. The "somehow" means that even if someone doesn't comprehend enough to have "confidence in the explanation", that lack of confidence will have zero effect on the real-world outcome - the energy involved in destructive interference wave cancellation will be preserved through constructive interference based on the conservation of energy principle. Please feel free to prove them wrong. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 2, 5:39*am, K1TTT wrote:
photons are good when working with other elementary particle interactions to represent the em energy lost or transferred during particle interactions. *they are not that useful when studying wave propagation or interaction with macroscopic object... including 1/4 wave coatings. Photons are useful for proving that EM waves must necessarily travel at the speed of light in the medium. Photons cannot stand still - therefore, EM waves, known to consist of photons, cannot stand still - therefore any overly-simplified mashed-potatoes version of energy stored in an RF transmission line violates the laws of physics. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 2, 1:39*pm, Cecil Moore wrote:
On Jun 2, 5:39*am, K1TTT wrote: photons are good when working with other elementary particle interactions to represent the em energy lost or transferred during particle interactions. *they are not that useful when studying wave propagation or interaction with macroscopic object... including 1/4 wave coatings. Photons are useful for proving that EM waves must necessarily travel at the speed of light in the medium. Photons cannot stand still - therefore, EM waves, known to consist of photons, cannot stand still - therefore any overly-simplified mashed-potatoes version of energy stored in an RF transmission line violates the laws of physics. -- 73, Cecil, w5dxp.com wave function solutions to maxwell's equations are enough to prove that for me. |
Question about "Another look at reflections" article.
On Jun 2, 8:57*am, K1TTT wrote:
wave function solutions to maxwell's equations are enough to prove that for me. Not a loaded question: How do Maxwell's equations applied to a standing wave prove that the component forward and reflected waves are moving at the speed of light in the medium? If it can and if I can understand it, I wouldn't need to use the photon argument. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 2, 2:12*pm, Cecil Moore wrote:
On Jun 2, 8:57*am, K1TTT wrote: wave function solutions to maxwell's equations are enough to prove that for me. Not a loaded question: How do Maxwell's equations applied to a standing wave prove that the component forward and reflected waves are moving at the speed of light in the medium? If it can and if I can understand it, I wouldn't need to use the photon argument. -- 73, Cecil, w5dxp.com easy, maxwell's equations don't predict standing waves! they are a product of superposition and the simplest instrumentation used since they were first discovered. |
Question about "Another look at reflections" article.
On Jun 2, 9:31*am, K1TTT wrote:
easy, maxwell's equations don't predict standing waves! *they are a product of *superposition and the simplest instrumentation used since they were first discovered. Please correct me if I am wrong: If one starts with the (superposed) standing wave equation, V(x,t) = A*sin(kx)*sin(wt), Maxwell's equations seem to provide a perfectly valid result (not that I can recognize perfection). Therefore, how do Maxwell's equations prove that the component traveling waves necessarily possess a separate existence? Again, a serious question from an engineer who considers anything except a logical '0' or logical '1' to be broken. :-) -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 2, 3:13*pm, Cecil Moore wrote:
On Jun 2, 9:31*am, K1TTT wrote: easy, maxwell's equations don't predict standing waves! *they are a product of *superposition and the simplest instrumentation used since they were first discovered. Please correct me if I am wrong: If one starts with the (superposed) standing wave equation, V(x,t) = A*sin(kx)*sin(wt), Maxwell's equations seem to provide a perfectly valid result (not that I can recognize perfection). Therefore, how do Maxwell's equations prove that the component traveling waves necessarily possess a separate existence? Again, a serious question from an engineer who considers anything except a logical '0' or logical '1' to be broken. :-) -- 73, Cecil, w5dxp.com my differential calculus is a bit rusty, but i don't think that equation satisfies the basic wave equation. from Fields and Waves in Communication Electronics, section 1.14. a solution for the wave equation in a transmission line (or other 1d form) must satisfy the condition that the 2nd derivative wrt x and wrt t equal v-squared... too hard to write in text. but basically take the above and differentiate twice wrt time and twice wrt distance and i don't think you'll get anything that comes out to the velocity squared. the problem is that t and x must be part of the same sinusoid in the F(t-x/ v) so that the wave is truly traveling instead of stationary like your equation provides. in the basic maxwell equations in differential form you also run into the same problem where the curl of the one field is proportional to the time derivative of the other i think you'll end up with a contradiction like k=w if you eliminate the dimensionless terms... i may be wrong on that because its been so long since i've had to deal with them on that level. |
Question about "Another look at reflections" article.
On 2 jun, 13:48, K1TTT wrote:
On Jun 2, 3:13*pm, Cecil Moore wrote: On Jun 2, 9:31*am, K1TTT wrote: easy, maxwell's equations don't predict standing waves! *they are a product of *superposition and the simplest instrumentation used since they were first discovered. Please correct me if I am wrong: If one starts with the (superposed) standing wave equation, V(x,t) = A*sin(kx)*sin(wt), Maxwell's equations seem to provide a perfectly valid result (not that I can recognize perfection). Therefore, how do Maxwell's equations prove that the component traveling waves necessarily possess a separate existence? Again, a serious question from an engineer who considers anything except a logical '0' or logical '1' to be broken. :-) -- 73, Cecil, w5dxp.com my differential calculus is a bit rusty, but i don't think that equation satisfies the basic wave equation. *from Fields and Waves in Communication Electronics, section 1.14. *a solution for the wave equation in a transmission line (or other 1d form) must satisfy the condition that the 2nd derivative wrt x and wrt t equal v-squared... too hard to write in text. *but basically take the above and differentiate twice wrt time and twice wrt distance and i don't think you'll get anything that comes out to the velocity squared. *the problem is that t and x must be part of the same sinusoid in the F(t-x/ v) so that the wave is truly traveling instead of stationary like your equation provides. in the basic maxwell equations in differential form you also run into the same problem where the curl of the one field is proportional to the time derivative of the other i think you'll end up with a contradiction like k=w if you eliminate the dimensionless terms... i may be wrong on that because its been so long since i've had to deal with them on that level. Oh!, I surrender :) The thread do not converge to a solution, it seems run out toward a naked singularity! I stay tuned until this good brainstorm calms down .. Miguel |
Question about "Another look at reflections" article.
On Jun 2, 5:56*pm, lu6etj wrote:
On 2 jun, 13:48, K1TTT wrote: On Jun 2, 3:13*pm, Cecil Moore wrote: On Jun 2, 9:31*am, K1TTT wrote: easy, maxwell's equations don't predict standing waves! *they are a product of *superposition and the simplest instrumentation used since they were first discovered. Please correct me if I am wrong: If one starts with the (superposed) standing wave equation, V(x,t) = A*sin(kx)*sin(wt), Maxwell's equations seem to provide a perfectly valid result (not that I can recognize perfection). Therefore, how do Maxwell's equations prove that the component traveling waves necessarily possess a separate existence? Again, a serious question from an engineer who considers anything except a logical '0' or logical '1' to be broken. :-) -- 73, Cecil, w5dxp.com my differential calculus is a bit rusty, but i don't think that equation satisfies the basic wave equation. *from Fields and Waves in Communication Electronics, section 1.14. *a solution for the wave equation in a transmission line (or other 1d form) must satisfy the condition that the 2nd derivative wrt x and wrt t equal v-squared... too hard to write in text. *but basically take the above and differentiate twice wrt time and twice wrt distance and i don't think you'll get anything that comes out to the velocity squared. *the problem is that t and x must be part of the same sinusoid in the F(t-x/ v) so that the wave is truly traveling instead of stationary like your equation provides. in the basic maxwell equations in differential form you also run into the same problem where the curl of the one field is proportional to the time derivative of the other i think you'll end up with a contradiction like k=w if you eliminate the dimensionless terms... i may be wrong on that because its been so long since i've had to deal with them on that level. Oh!, I surrender *:) The thread do not converge to a solution, it seems run out toward a naked singularity! *I stay tuned until this good brainstorm calms down .. Miguel it will never converge, these discussions always go on until the namecalling starts, then die an ugly death. |
Question about "Another look at reflections" article.
On Jun 2, 8:00*am, Cecil Moore wrote:
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. Refering to photons is just fine. Just do not mix them in with wave theory. 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." All quite orthogonal to the original point, but your point about standing waves is quite correct, they are not really waves at all. But your need for the reality of underlying waves is quite excessive. The voltage and current distribution on a transmission line can be solved with a set of differential equations which satisfy some boundary conditions. There is no mention of forward and reverse waves in this solution. Turns out though, that the solution can also be factored in to a forward and reflected wave and this technique will provide the same answer. It does not make these waves any more real. I bring you back to a previous question which you have never answered... On an ideal line with 100% reflection, there are points where the current and voltage is always 0. Knowing that if either current or voltage is 0, power is also 0, how does energy cross these point? And if I cut the line at all the places where the current is zero, it does not alter the energy distribution on the line one iota. How can this be if energy is travelling from end to end on the line? 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. PHYSICS has long given up on the idea of waves being an explanation for light. The wave theory fails miserably when illumination levels drop to the level that individual photons are being detected. Though of course the earlier approximate models (waves) are still useful when intensity is high enough, just as we still use Newtonian mechanics to solve many every-day problems. You might like to try http://vega.org.uk/video/subseries/8 for an exposition on the strangeness of photon. 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. There you go again... mixing up you models. EM waves are analog and in no way encompass the quantum nature of photons. 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 seems to be some misapprehension here. No one has claimed that EM waves stand still, though you may have been confused by the word 'standing' in 'standing waves'. But then earlier in your post you quote 'College Physics' about 'standing waves', so it is not clear where your confusion originates. 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. They are not both correct. QED aligns with many more observations than does the wave theory. Another reason not to mix them. 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. And the wave theory does disagree with QED at low levels, while at higher illumination levels QED agrees with the wave theory. 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". And yet known of this aligns with the photons being part of the wave theory of light. They two theories remain distinct. http://www.teachspin.com/instruments...eriments.shtml I, personally, am not interested in getting the right answer using the wrong concepts. Well, (and I am sorry, I can not resist), there is some evidence to the contrary. See: http://www.w5dxp.com/energy.htm http://www.w5dxp.com/nointfr.htm ....Keith |
Question about "Another look at reflections" article.
On Jun 2, 6:33*pm, Keith Dysart wrote:
The voltage and current distribution on a transmission line can be solved with a set of differential equations which satisfy some boundary conditions. I am not interested in voltage and current. Like optical physicists, I am only interested in tracking the RF energy flow. It does not make these waves any more real. Agreed, but the point is that it does not make the traveling waves any LESS real! I bring you back to a previous question which you have never answered... On an ideal line with 100% reflection, there are points where the current and voltage is always 0. Knowing that if either current or voltage is 0, power is also 0, how does energy cross these point? Good grief, I have answered that question at least a dozen times. The net current being zero is just an illusion caused by superposition of two magnetic fields propagating in opposite directions that are equal in magnitude and opposite in phase. The two traveling waves keep on trucking at their relatively constant ExH energy levels in opposite directions. If you want to account for the energy, when the current is zero, all of the energy existing at that point is in the electric field and, sure enough, the voltage is at a maximum at that point- duuuhhhh again. There is absolutely no point on an active transmission line where the net energy level is zero. Again, you guys are never going to convince anyone that the Golden Gate Bridge doesn't need maintenance because the net traffic on the bridge is zero. How the heck can thousands of vehicles traveling one direction while the same number of vehicles are traveling in the opposite direction add up to zero effect in reality? Please get real. And if I cut the line at all the places where the current is zero, it does not alter the energy distribution on the line one iota. How can this be if energy is travelling from end to end on the line? As I told you years ago, when you cut the line, you radically change the impedance and create a reflection that didn't exist before you cut the line. Hint: There are no reflections at a point of constant Z0. There are only reflections at an impedance discontinuity. The alteration of the energy distribution (to which you seem to be blind) can easily be observed in a TV system. PHYSICS has long given up on the idea of waves being an explanation for light. And RF waves are technically light, just not visible light. When I was rummaging through the Texas A&M library, I found a book entitled, "Light". It covered the subject of RF waves. EM waves are analog and in no way encompass the quantum nature of photons. You could become famous if you can prove that EM waves are not quantized. Good luck on that one. No one has claimed that EM waves stand still, ... Please prove your ridiculous assertion that no one has ever claimed that EM waves can stand still. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
On Jun 2, 11:48*am, K1TTT wrote:
my differential calculus is a bit rusty, but i don't think that equation satisfies the basic wave equation. My calculus is probably a lot rustier than yours but it would be very important for this discussion if Maxwell's equations do not work for the standing wave equation. That would essentially prove that the mashed-potatoes theory of transmission line energy is bogus. -- 73, Cecil, w5dxp.com |
Question about "Another look at reflections" article.
lu6etj wrote:
Oh!, I surrender :) The thread do not converge to a solution, it seems run out toward a naked singularity! I stay tuned until this good brainstorm calms down .. Good day Miguel, you must be new here! I don't think any threads converge to a solution. Mostly they do that singularity thing after about the third message. But hang in there, often much entertainment is to be had! |
Question about "Another look at reflections" article.
On Jun 2, 12:56*pm, lu6etj wrote:
Oh!, I surrender *:) The thread do not converge to a solution, ... Miguel, do you fully realize the importance of Maxwell's equations being nonfunctional with the equation for standing waves? It means that any analysis based entirely on standing waves is probably invalid in some area of the analysis - probably including Keith Dysart's latest postings about the standing wave's zero current being meaningful in some way. -- 73, Cecil, w5dxp.com |
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