Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: McQueen on 03/12/2007 23:43:04
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The other day I was doing something quite mundane, maybe frying an egg or something, I don’t recall exactly what it was. But then it suddenly occurred to me the precision with which science is able to explain almost every phenomena in such excruciating detail that everything, from the trajectory of a drop of sputtering oil to the fertilization of an orchid, can be seen as a series of minutely connected events. It is truly amazing if you think about it, superstition, which played such an important role throughout human history, has been almost overwhelmed by such detailed knowledge. The very fact that such knowledge can exist is almost superstitious in itself. Why don’t unexplained things exist, it seems almost a paradox in itself. Why do events have such perfect explanations ?
Yet when it comes to the photon, and forget for the moment the difference between the macro and the micro world and stick to available solutions. Why did Physicists choose a model of the photon in which it was neither a particle nor a wave? I can understand if physicists said that the photon is a synthesis between a wave and a particle. But this is expressly what it is understood what it is not meant to be.
My question is, leaving aside for the moment the question of the maths behind the decision which is shaky to say the least, what gives the physicist the right to arbitrarily choose between two alternatives and then to maintain in the face of evidence to the contrary, showing that his theory is full of holes, that his decision was irrevocably right! Surely the rest of humanity, the artists and the philosophers and the so called rational man should have some say in the matter too?
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But do they do the experiments?
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The other day I was doing something quite mundane, maybe frying an egg or something, I don’t recall exactly what it was. But then it suddenly occurred to me the precision with which science is able to explain almost every phenomena in such excruciating detail that everything, from the trajectory of a drop of sputtering oil to the fertilization of an orchid, can be seen as a series of minutely connected events. It is truly amazing if you think about it, superstition, which played such an important role throughout human history, has been almost overwhelmed by such detailed knowledge. The very fact that such knowledge can exist is almost superstitious in itself. Why don’t unexplained things exist, it seems almost a paradox in itself. Why do events have such perfect explanations ?
Yet when it comes to the photon, and forget for the moment the difference between the macro and the micro world and stick to available solutions. Why did Physicists choose a model of the photon in which it was neither a particle nor a wave? I can understand if physicists said that the photon is a synthesis between a wave and a particle. But this is expressly what it is understood what it is not meant to be.
My question is, leaving aside for the moment the question of the maths behind the decision which is shaky to say the least, what gives the physicist the right to arbitrarily choose between two alternatives and then to maintain in the face of evidence to the contrary, showing that his theory is full of holes, that his decision was irrevocably right! Surely the rest of humanity, the artists and the philosophers and the so called rational man should have some say in the matter too?
I think your principal mistake is to think that a "photon" have to be "something" precisely defined, at least because it has a simple name. Physicists give it such a simple name because it would be more long to talk about "quantum of energy in the electromagnetic field" every time.
1.Does this definition mean there is "something" which propagates from source to detector?
2.If your answer is "yes" then can you tell me of what and how this "something" is made? Don't ask me or yourself this question, ask it to some very expert physicist, then bring here the answer and we will discuss it.
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Surely the rest of humanity, the artists and the philosophers and the so called rational man should have some say in the matter too?
Would you hire artists and philosophers with no training to draw up blueprints for building your car? It would probably be a very interesting design, but it would also fall apart on the highway. For the same reason, you need to make sure the models of light hold up on the highway of reality. The photon is currently the best fundamental model of light.
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If you can come up with a more satisfactory model which precisely matches all existing experimental results at least as well as the currently-accepted theory (fudge, if you insist), then go ahead...
It gets tricky when you come to single-photon double-slit interference experiments(!) ...
Be careful though, because some oft-quoted results turn out only to be gedanken (thought) experiments - so check your sources carefully.
See also: http://en.wikipedia.org/wiki/Light
and note that electrons as well as photons have this strange "wave-particle duality"
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Would you hire artists and philosophers with no training to draw up blueprints for building your car? It would probably be a very interesting design, but it would also fall apart on the highway.
That is precisely the point, neither would I hire a spiritualist or psychic for the same job. It is this very point that I am arguing about. When solutions do exist that are within the realm of the natural, why go into the supernatural to explain the behaviour of matter. For instance light is supposed to disassociate or disembody itself when it is traveling from one place to another. To me this sounds like a whole lot of mumbo-jumbo concocted by a witch doctor. This is not the only example of venturing into the supernatural, I can quote at least five or six examples to illustrate the point.
If you can come up with a more satisfactory model which precisely matches all existing experimental results at least as well as the currently-accepted theory (fudge, if you insist), then go ahead...
Believe me I was not the one to come up with this theory. This was the theory that existed before these particular weird aspects of QM came along to explain things. Only now it looks as if it can be be and is being substantiated by new discoveries. Keep an open mind!
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I would recommend a reading of two of the greats in the philosophy of science Karl Popper [http://en.wikipedia.org/wiki/Karl_Popper] (falsifiability being cornerstone, never absolute proof) and then Thomas Kuhn [http://en.wikipedia.org/wiki/Thomas_Kuhn] who talks at length about inherent conservatism of scientific opinion (received wisdom) which is only advanced through great changes - paradigm shifts. Popper ehlps understand the true scientific mindset and Kuhn then sets about destroying it.
Matthew
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To me this sounds like a whole lot of mumbo-jumbo concocted by a witch doctor. This is not the only example of venturing into the supernatural, I can quote at least five or six examples to illustrate the point.
It is the supernatural, if, by that, you mean something outside the experience of Natural Scientists up to the point the idea developed. It is just one of those things which are not explicable using the cosy, familiar ideas of the classical Physicist.
Physics is not the only area where this happens. Look at Maths; every few years there is an entirely new bit of maths which comes out, needing a new way of looking at things. Are imaginary numbers supernatural? They may have been regarded that way by the establishment of the time but now?
Also, perhaps you could quote a couple of your five or six examples.
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It is the supernatural
Why ???? When supernatural phenomena clearly do not exist in the world we live in. Why opt for a supernatural solution when a perfectly natural solution exists? That is precisely the point of this post. Look at your argument familiar, cosy are these the terms that physicists normally use. Can you imagine describing Newton’s Laws of motion in terms of ‘cosy’ and 'familiar'. I am telling you the whole idea of introducing the supernatural into physics is utterly absurd. The most absurd aspect of this situation is that physicists are not even willing to discuss anything new. It is as if what they had to say was in the form of a caveat .
Let us look at whjat you had to say more closely!
It is the supernatural, if, by that, you mean something outside the experience of Natural Scientists up to the point the idea developed. It is just one of those things which are not explicable using the cosy, familiar ideas of the classical Physicist.
'..............something outside the experience of Natural Scientists upto the point the idea developed."
Sp suddenly because an idea 'develops' we have supernatural phenomena? Come on give me a break. I am sure that millions upon millions of people would love to have Harry Potter kind of scenarios in their everday lives, but that does not mean it is going to happen!
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The most absurd aspect of this situation is that physicists are not even willing to discuss anything new.
Physicists are perfectly willing to discuss new ideas, and they're also willing to accept that old ideas aren't 100% accurate as well. If you want to get a new theory accepted, you need to make sure it matches all current results, and then use it to predict some things that other models can't. If you simply want to discredit the photon model of light, then you need to actually give some proof. You claim that the theory is "full of holes," but you have yet to actually describe any problems with it aside from your objection that you think it's "supernatural."
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You claim that the theory is "full of holes," but you have yet to actually describe any problems with it aside from your objection that you think it's "supernatural."
This is really phenomenal, You are so wrapped up in mathematics that you can't seem to see the forest for the trees! Wake up and smell the coffee! Look an object cannot disembody itself, if you want clarification on what this means. An object starts of at point A it then dismbodies itself,(i.e., exists in all places between point A and point B) until it finally re-manifests itself at point B. Apart from disembodiment, an object cannot be in two places at the same time! An object cannot possess two separate identities at the same time. If an object does posses any of these attributes it is supernatural. OK. So that is the definition of supernatural, what is there for me to describe.
Furthermore this is extremely important to everyone, not just some tacky physical point. Look around you. everything that you see is conveyed to the senses by photons!
So how it happens is important, not only to physicists but to everyone else.
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Everyone seems to be saying, ‘OK so you don’t like our theory: Give us an alternate Theory.’
Conveniently forgetting that I did put forward an alternate theory
A new Classical Physics (http://www.thenakedscientists.com/forum/index.php?topic=11540.0) .
This might sound hard to believe but I purposely said something absurd in that thread, just to see what the reaction would be. What I said contradicted the neutrality of the photon. (i.e., I said that electromagnetic waves would be affected by an electric field or a magnetic field.) I made this statement just in order to see what the reaction would be. The reaction was predictable there was almost a consensus that the whole theory was ridiculous and that it should be buried in the New Theory section of this Forum. Why did I make the statement, when I knew that it was false, well physicists make the most ridiculous statements, supported as I have said before by the most shaky of mathematical foundations, and for the most part go unchallenged. I just wanted to see whether a normal reaction could be elicited when I made an unfounded and blatantly false statement!
But think about it, the neutrality of the photon is one of its fundamental properties, would I overlook such an important aspect of it? You can see from web-site that I had in fact addressed this aspect first . What is interesting however, is that,. The other nine corresponding properties of the photon that my theory explains perfectly, were completely ignored.
The Gestalt Theory of Light and related phenomena, does explain almost every property of the photon:
(1) It explains wave-particle duality.
(2) It explains why such huge variations in photon wave-length and energies are possible.
(3) It explains how a tiny particle like an electron can emit huge wave-lengths of 1Km or more.
(4) It explains why photons travel at the speed of light . It even explains why the speed of light is constant.
(5) It explains the neutrality of the photon.
(6) It explains how the photon retains its energy intact until it is absorbed.
(7) It explains, in a workable manner and for the first time, the difference between radio frequencies and optical frequencies, while still maintaining the same basic identity for the photon.
(8) It explains how photons of different energies are formed.
And the wonderful thing about all this is that it does so, without recourse to anything supernatural, and is based on hypotheses formulated by Classical physicists. Gestalt Theory is simple to understand, there are no complicated concepts. Anyone can understand it and say, as lightarrow did, Hey! This is wrong!
So there you have it. I say something ridiculous and it is immediately pounced on and disposed of with despatch.
You say something ridiculous, like light is both a wave and a particle or that light undergoes disembodiment as it travels from point A to point B and everyone applauds, because it is supposedly supported by mathematics which is in reality just a mumbo-jumbo of abstractions and in the end explains nothing.
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You claim that the theory is "full of holes," but you have yet to actually describe any problems with it aside from your objection that you think it's "supernatural."
This is really phenomenal, You are so wrapped up in mathematics that you can't seem to see the forest for the trees! Wake up and smell the coffee! Look an object cannot disembody itself, if you want clarification on what this means. An object starts of at point A it then dismbodies itself,(i.e., exists in all places between point A and point B) until it finally re-manifests itself at point B. Apart from disembodiment, an object cannot be in two places at the same time! An object cannot possess two separate identities at the same time. If an object does posses any of these attributes it is supernatural. OK. So that is the definition of supernatural, what is there for me to describe.
Do you remember when I wrote that a photon is not an object?
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I was trying to stimulate this interchange in an earlier thread but, maybe the ideas will come out here. My view:
Photons are not little bullets. All they are is small portions of energy. If you don't allow for something like a photon then atoms just wouldn't work as they do. If you didn't postulate photons, you'd have to go for something similar.
At times, the way that they interact with matter can be treated 'as if' they were little bullets but no one says they actually are.
The 'size of a photon' only relates to the region of space where it is most probable to have an effect. The shape of that region seems to be best described in terms of waves.
An atom is small compared with optical wavelengths so the emitted photon has an influence (radiation pattern, in antenna terms) which covers a huge solid angle. Because of the dipole-like nature of the electron's so-called orbit, the field is not omnidirectional, more doughnut shaped.
The photon has a life which is limited by how long the actual emission and absorption take and the time to travel from one atom to the other. Its size just relates to this time and c - but there is no point in trying to nail it down because Heisenberg gets in the way. No worries, though.
Whilst the photon energy is spreading out into space, it is 'up for grabs' by any atom in an appropriate state. There is a bit of 'quantum magic', if you like, which says that, once the photon has been absorbed by an atom over here (or even just started to be absorbed), all its energy is committed and an atom 'over there' can't have it. That implies some communication, in an instant, as the photon's energy collapses everywhere else. Quantum entanglement isn't an unreasonable idea and has been shown to occur in many events. It's a new idea, of course, but it's not just 'mumbo jumbo'. You can't make a computer with mumbo jumbo - there has to be some reliable science to produce the technology at work in a quantum computer.
So, the photon doesn't have to be an object and it doesn't actually have to be a wave. It is just a 'construct' which can be used to explain a very common phenomenon. School and TV Science is no help at all, if you want to understand this whole business; it just clouds the issue and needs to be un-learned by students who want to progress.
This area of Physics is fascinating to lay people but the level of comprehension needed to 'get it' is along the lines of Integral Calculus. However, very few lay people feel inclined to take Calculus on board just because it sounds fascinating, so there are many fewer mis-conceptions about Maths than about Physics. How many popular broadcasters would have the nerve to stand in front of TV camera and spout bollocks about Maths in the way that they do about Science?
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I am still having a problem explaining, satisfactorily, the interaction of a (conducting) reflecting surface with a beam of light and using the photon idea.
There is an implication that, although the fields associated with photons don't actually affect each other (superposition rules) the interference / diffraction patterns determine the most likely direction in which most of the reflected photons will interact with a target object lies along the 'conventional' reflected beam.
I suppose, in fact, it is similar to the two slit interference problem and best dealt with using wave theory.
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I was trying to stimulate this interchange in an earlier thread but, maybe the ideas will come out here. My view:
Photons are not little bullets. All they are is small portions of energy.
Yes and, furthermore, it's even tricky to prove that this "quantized energy" propagates from source to detector; some thinks this quantization of energy happens only when the wave interacts with the detector (or with matter in general).An atom is small compared with optical wavelengths so the emitted photon has an influence (radiation pattern, in antenna terms) which covers a huge solid angle. Because of the dipole-like nature of the electron's so-called orbit, the field is not omnidirectional, more doughnut shaped.
AFAIK, it's worse than that: you can't predict where, in all the solid angle, the photon will be emitted. I can be wrong however.
I agree with the rest of your post.
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I am still having a problem explaining, satisfactorily, the interaction of a (conducting) reflecting surface with a beam of light and using the photon idea.
There is an implication that, although the fields associated with photons don't actually affect each other (superposition rules) the interference / diffraction patterns determine the most likely direction in which most of the reflected photons will interact with a target object lies along the 'conventional' reflected beam.
I suppose, in fact, it is similar to the two slit interference problem and best dealt with using wave theory.
It's right. You find every possible path and then you sum the amplitudes. Then you square the final amplitude to find the probability. That's essentially the same as the two-slits experiment.
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you can't predict where, in all the solid angle, the photon will be emitted
You were quick!
My point is that you have no idea at all - it's undetermined until something, somewhere, resonates with the field and then grabs all the energy.
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It's right. You find every possible path and then you sum the amplitudes
Yes - but you are using the classical (Huygens) approach. (BTW, you add the phasors not the amplitudes!) It works perfectly but I was trying to think in terms of one photon and where it would be most likely to end up. I guess that's a nonsense question, really - falling into the same trap that I was complaining about!
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Do you remember when I wrote that a photon is not an object?
Would you mind if I rephrased your question to read : “Do you remember when I wrote that I think that a photon is not an object." The reason I say this is that as Einstein so succinctly put it. All physical theories are a free creation of the human mind. There is no guarantee that this is how nature really is. The theory stands or falls on its ability to predict a series of events.
As I understand, traditional wisdom states that waves are a form of matter as are particles, so how you can arrive at the conclusion that photons are not objects, I cannot immediately see. What I do understand is that my model of the photon as outlined in Gestalt theory, does stand up to the closest scrutiny and does offer a solution for a photon’s behaviour and attributes within the framework of nature and without resorting to any anomalous concepts.
Whilst the photon energy is spreading out into space, it is 'up for grabs' by any atom in an appropriate state. There is a bit of 'quantum magic', if you like, which says that, once the photon has been absorbed by an atom over here (or even just started to be absorbed), all its energy is committed and an atom 'over there' can't have it. That implies some communication, in an instant, as the photon's energy collapses everywhere else. Quantum entanglement isn't an unreasonable idea and has been shown to occur in many events.
Let us consider your statement and see how well it holds water! OK so you have a photon and it’s energy is spreading out into space. Reason tells us that it is dissipating its energy as it does this, am I right? This is similar to a wave spreading out in a pond as it travels further and further from the source, its energy gets dissipated. But then you rationalize this by saying that all of the photon’s energy is ‘up for grabs’ and is transferred to the first atom it comes into contact with. A difficult concept to come to grips with and it might work if you are dealing with nano distances. But consider that photons have been detected which have traveled billions of kilometers, and aside from a slight red-shift they have conserved their energy (identity) over this tremendous distance. Now what according to you happens to this energy, I’ll quote you if I may ‘………. The photon’s energy is spreading out into space!” The exclamation mark is mine. So stripped of your comments about the lack of ability in a layman to understand these concepts and a need to understand Calculus in order to comprehend, what do you really have? OK you are going to come back by saying that while it is traveling the photon takes the form of a wave, then how on earth does it retain it energy intact? You tell me.
By contrast Gestalt theory is able to explain how a photon can travel these vast distances and still retain its identity. There is nothing complicated in the theory. It is something that works. It explains all the properties of a photon without any contradictions.
P.S Predictably Light arrow agrees with everything you have to say !
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It's right. You find every possible path and then you sum the amplitudes
Yes - but you are using the classical (Huygens) approach. (BTW, you add the phasors not the amplitudes!) It works perfectly but I was trying to think in terms of one photon and where it would be most likely to end up. I guess that's a nonsense question, really - falling into the same trap that I was complaining about!
Actually, I had in mind the way Feynman makes the computation with a particle's wavefunction in the book "QED".
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Do you remember when I wrote that a photon is not an object?
Would you mind if I rephrased your question to read : “Do you remember when I wrote that I think that a photon is not an object." The reason I say this is that as Einstein so succinctly put it. All physical theories are a free creation of the human mind. There is no guarantee that this is how nature really is. The theory stands or falls on its ability to predict a series of events.
Ok. So, if it's an object, can you tell me, for example, its dimensions?
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I'll admit that physicists are conservative. We don't like changing our models until we have to. However, if a theory is incomplete (and yes, we know that the current models which predict the photon are incomplete, at the very least since they can't explain gravity), we are willing to accept new theories. These new theories do have to match with known experimental evidence however, and usually have to predict new testable results. Special relativity, general relativity, quantum mechanics, and quantum field theory are all examples of radical new theories that came about in the past 100 years or so because physicists realized their theories needed to change.
Your problem isn't so much with physicists not accepting new theories, but with physicists not accepting your theory. Of course they don't, since the theory you proposed neither makes testable predictions nor agrees with prior observations. Either your theory has flaws in it, or you're purposely proposing a flawed theory, as you claim "just to see what the reaction would be." Even if you do have a perfect theory in your back pocket, physicists won't take your theory seriously if you keep purposely making up wrong theories just to see what happens.
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Ok. So, if it's an object, can you tell me, for example, its dimensions?
Let us take stock of what we know. The electron is a charged particle. So it is probable that what the electron is emitting or absorbing when it wants to lose or gain energy is electrical energy. We assume that when it has extra energy which it wishes to lose, the electron fires of a very rapid series of pulses of electrical energy, with the first such pulses being stronger and successive pulses of energy being weaker, giving a polarity to the whole structure of pulses of electrical energy being emitted or absorbed. This basically is the structure of what we think of as photons. (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.geocities.com%2Fnatureoflight%2Fphotonemission1.bmp&hash=4d811831b8d68d70d3f6da49092b81c9)
The thing to remember here is that even though the classical diameter of the electron is extremely small about 10^^-13 cms. this firing off or absorbing of a series of electrical pulses is well within the electron’s capability. The end result of the polaristion of the charged pulses emitted by the electron result in the forming of a type of solenoidal field around the series of pulses.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.geocities.com%2Fnatureoflight%2Fphotonemission.bmp&hash=78e56bdceb4c729b059fed0ad8484958)
This structure lends several attributes to the photon. The structure resembles that of an electrical capacitor, as such it is capable of retaining its energy almost indefinitely. Similarly this structure also contributes to the neutrality of the photon it is not affected by other forces but is a self contained unit. Here is the final picture of what a fully formed photon might look like. (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.geocities.com%2Fnatureoflight%2Fphoton.bmp&hash=c61560c190f0294519777e1685ff115d)
Note also that the structure of the photon as described makes it easy to be both absorbed and emitted by the electron. This is the structure and sequence of events that go into the forming of a photon according to Gestalt Theory.
This structure also offers a very simple explanation of how an electron is able to emit the more than billions of frequencies associated with optical photons. It is just a simple variation in energy levels. So all that an electron need do to emit a photon of a different frequency or energy is to vary the amount of energy it is emitting!
A photon's frequency varies with is wavelength according to the relation f = hc/l. Isn't it simple to understand, doesn't it bring to mind Occam's razor? Look at QM by contrast!!
Gestalt theory offers a different explanation for the formation of radio frequency photons though the photon structure is absolutely the same as that for optical photons.
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Your problem isn't so much with physicists not accepting new theories, but with physicists not accepting your theory. Of course they don't, since the theory you proposed neither makes testable predictions nor agrees with prior observations. Either your theory has flaws in it, or you're purposely proposing a flawed theory, as you claim "just to see what the reaction would be." Even if you do have a perfect theory in your back pocket, physicists won't take your theory seriously if you keep purposely making up wrong theories just to see what happens.
The challenge is taken up, ask me any question and if the answer I give you is not more compact, more to the point and more reasonable than its QM counterpart. I will apologise. Ask a question show that you have an open mind!
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Written whist other posts were being made:
One problem with discussing your Gestalt theory is that I haven't read it all, yet. Where can I read it in full? I understand that it is in the process of being written up so, when complete, we could discuss it in depth, perhaps.
The photon’s energy is spreading out into space!” The exclamation mark is mine. So stripped of your comments about the lack of ability in a layman to understand these concepts and a need to understand Calculus in order to comprehend, what do you really have? OK you are going to come back by saying that while it is traveling the photon takes the form of a wave, then how on earth does it retain it energy intact? You tell me.
I should, perhaps have written "the photon's influence is spreading out into space" . I was not implying an inverse law because, of course, one photon's energy would not amount to much if spread out. The fact is that SOMETHING is different about the photon from the naive picture of it and it requires some new thinking. Keeping the wave model, wherever possible, explains everything about the macroscopic behaviour of lots of photons - or even the statistics of small numbers, so that absolutely has to be part of any useful model. Insisting that the photon be treated as some sort of bullet brings in no end of conflicts about size and lifetime, etc. The idea of 'influence', as I describe (not a complete theory, of course; I would not have the temerity for that) does not introduce any particular conflicts - except that it involves some idea of instantaneous effect at a distance - merely quantum entanglement.
I was not being elitist by mentioning the calculus thing. It is just that the whole subject of Physics is more demanding than many people acknowledge and that theories are only worth while considering if they are founded on solid knowledge and established understanding. You can't dream them up overnight and expect them to hold water.
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Apart from the familiar wave equation, you include no maths and you haven't answered the initial question about how big this photon is supposed to be. Quite a relevant question, I should think so let that be the first one to challenge you with.
Occam's Razor involves casting out what is 'unnecessary' but you have to leave something worthwhile behind!
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Keeping the wave model, wherever possible, explains everything about the macroscopic behaviour of lots of photons - or even the statistics of small numbers, so that absolutely has to be part of any useful model.
Surely you must see that the model of the photon I had given in the previous post is both a wave and a particle. It is a wave in the sense that it is not a particle and it is a particle in the sense that it contains enough energy to produce the effect of being a particle. I assure you that I will address your request that a full account of the theoryy be published as soon as possible.
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Two questions:
Ok. So, if it's an object, can you tell me, for example, its dimensions?
Second,
Your photon has the form of an electric dipole. As mentioned before, dipoles experience a torque in an external electric field. Say I want to fire a laser (photons) in a strong electric field? Can you predict what effect this would have on your the laser beam? If you claim it has no effect, can you explain that in terms of Maxwell's equations, or are you proposing that Maxwell's equations are incorrect? If the latter, what do you propose to replace them with?
The QM answer to this second question is pretty simple: "Maxwell's equations hold. Photons do not have charge and therefore do not interact with electric fields (or other photons)."
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Apart from the familiar wave equation, you include no maths and you haven't answered the initial question about how big this photon is supposed to be. Quite a relevant question, I should think so let that be the first one to challenge you with.
How big is the photon? Well as you can see it has a wave-like origin, since there are so many possible photon energies it is not possible to give an exact physical size, although this should not, exceed a few nanonmeters in breadth or length.
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Your photon has the form of an electric dipole. As mentioned before, dipoles experience a torque in an external electric field. Say I want to fire a laser (photons) in a strong electric field? Can you predict what effect this would have on your the laser beam? If you claim it has no effect, can you explain that in terms of Maxwell's equations, or are you proposing that Maxwell's equations are incorrect? If the latter, what do you propose to replace them with?
Excuse me for saying that this is either a deliberately obtuse question or one bordering on hypocrisy. Let me explain why I say this.
What was Maxwell’s greatest contribution? You could say it was the first unified field theory, unifying the electric and magnetic fields. Why? because in an electromagnetic wave neither can exist without the presence of another. Remember that when we are discussing photons we are discussing electromagnetic phenomenon. The point is have you ever heard of a magnetic monopole???
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ask me any question and if the answer I give you is not more compact, more to the point and more reasonable than its QM counterpart. I will apologise.
I await the apology.
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How big is the photon? Well as you can see it has a wave-like origin, since there are so many possible photon energies it is not possible to give an exact physical size, although this should not, exceed a few nanonmeters in breadth or length.
And where does that figure come from? What experimental / mathematical evidence is behind it? I notice you don't commit yourself to frequency or wavelength.
Give me sizes for gamma rays, yellow light and for 200kHz radio waves and justify it.
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And where does that figure come from? What experimental / mathematical evidence is behind it? I notice you don't commit yourself to frequency or wavelength.
Give me sizes for gamma rays, yellow light and for 200kHz radio waves and justify it.
The answer I am going to give to your question may astound, amaze and stagger the imagination. It is that all photons, from those with wave-lengths kilometers long to gamma rays and x-rays, have basically the same dimensions, or in other words are the same size, only their energy varies. In order to explain how this is possible it is necessary to introduce you to some of the basic concepts of the Gestalt Theory:
Let us re-examine the Michelson Morley concept of measuring the speed of light, however instead of measuring the speed of light we measure the speed of an electric current flowing through a wire. However we find that there is no necessity for this as Maxwell had already established that the speed of a current flowing through a wire is the same as that of the speed of light. There seems at first glance to be nothing wrong with the statement until we realize that according to every theory including classical physics and QM, electricity is supposed to be carried by electrons while electromagnetic radiation is carried by photons. We are aware from experience that Photons travel at the speed of light, but electrons…………….?
We know from our work with particle accelerators etc., that even under millions of volts of potential difference it is not possible to accelerate an electron up to the speed of light. It might be possible to accelerate it to 99.99999 per cent of the speed of light but it is never possible to accelerate it to the speed of light. Isn’t this something of an anomaly? True, it is possible to explain the flow of electric current in a conductor in terms of the displacement current postulated by Maxwell. But, and this is interesting, the displacement current is just another term for an electromagnetic wave, or to use different terminology for photons.
The Pauli exclusion principle states categorically that free photons cannot emit or absorb photons because they would not be able to cope with the forces of recoil (i.e., they would have nothing to rebound upon and absorb the excess energy and so would violate the laws of the conservation of energy). A bound electron on the other hand has the nucleus to rebound upon and therefore is free to emit and absorb photons. So here is apparently a paradox. On the one hand the only way to explain the flow of current in a conductor at the speed of light is by means of photons ( interacting electrical and magnetic fields classically) on the other hand it is known that free electrons, necessary to explain such a process cannot absorb or emit electrons, because of the Pauli Exclusion Principle. One of these statements has to be wrong.
In order to explain the view that free electrons can in fact absorb and emit electrons, Gestalt theory has recourse to another little used aspect of the Heisenberg Uncertainty Principle. In addition to the reciprocal uncertainty of position and momentum, there is also a reciprocal uncertainty of time and energy. The less uncertainty there is about the time involved in a sub-atomic event the more uncertainty there is about the energy involved in the event ( and the other way round). Because of this uncertainty the conservation laws of mass-energy are not upset.
How does this apply to Gestalt Theory? Imagine a free electron in the vast interstitial spaces of an electrical conductor. When a potential difference is applied to the conductor a vast number of low level photons are released ( one cu cm of copper contains in excees 10^^23 electrons), these photons are of such low energy that they cannot be absorbed by bound electrons but can be absorbed by free electrons or even loosely bound outer electrons, provided that the free electron that has emitted a photon immediately reabsorbs another photon. This process must take place very fast at about 10^^-16 secs. if it to avoid violating the law of conservation of mass and energy. The virtual photons fields around the conductor are also affected by this process forming the lines of force described by Faraday. I have said that the photons released under a difference of potential are of very low energy, how then is electrical energy accounted for. The answer is that these photons are oriented or connected serially:
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Each line of force consisting of a number of photons carries the same amount of energy approx. 1.6 x10^^-19 J. No it is not a coincidence, each line of force carries approx the energy equivalent to the charge of an electron. While the photons are connected in series they convey electrical energy. This explains the phenomenon of induction perfectly, with no anomalies. If the current is varied rapidly and the distance between the conductor carrying a current and another conductor in close proximity, the current is transferred to the second conductor because the photons are still connected in series.
What happens when the current is stopped or varied and there are no conductors in close proximity? The photons change their orientation so that they are now connected in parallel.
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Photons when they are 'released' from the conductor change their orientation to a parallel orientation and move away from the conductor at the speed of light. They are no longer capable of inducing an indcutive current. They are now to all purposes neutral and will only interact with matter.
When photons are connected in parallel the original eigen value of 1.6 x 10 ^^ -19 J that the photons possessed when they were connected in series, is now divided by the
Time interval to give the new eigen value of each individual photon that is connected in parallel. Thus the energy of a 1m composite wave-length would be : 1.98 x 10^^ -25 /10^^0 = 1.98 x 10^^-26 J : dividing the composite wave length by the eigen wave length for free electrons and using the result to multiply the composite wave energy value i.e 1.98 x 10^^-26 x 10^^-7 again yields the individual eigen value for a free electron :1.98 x 10 ^^-19 J.
This configuration explains with no gaps everything to do with electricity, electromagnetic radiation and the formation of photons.
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What experimental / mathematical evidence is behind it?
I repeat this question.
Mere assertions don't prove anything.
The little pictures are very pretty and do your graphic skills credit but what do they prove?
I could do the same with pictures of bananas and it wouldn't necessarily make me correct.
btw, neither do the words Gestalt and Eigen lend any authority to your argument - they have not been defined so they are just like "Abracadabra".
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]I repeat this question.
Mere assertions don't prove anything.
The little pictures are very pretty and do your graphic skills credit but what do they prove?
I could do the same with pictures of bananas and it wouldn't necessarily make me correct.
btw, neither do the words Gestalt and Eigen lend any authority to your argument - they have not been defined so they are just like "Abracadabra".
Thank you for the compliment, the images are pretty? Let’s get down to the nitty gritty then. The term frequency has often been used in an anomalous way in physics. For instance take Einstein’s Photoelectric equation:
Hf = W + i/2 mv^^2max.
Where the ‘frequency’ needed to overcome the work function is defined. However in Gestalt theory the term ‘frequency’ has a very definite definition, it is defined as the number of photons of a given energy that an electron emits in a second. From this it is possible to get some idea of the ‘size’ of the photon. For instance take your example of x-rays, to Gestalt theory this would mean that an electron was emitting at the rate of approx 10^^16 photons a second. This is a very short time interval, so it is obvious that the length of the photon must also be small. Although given lack of funding it will not be possible to fix an exact limit without further experimentation, still between 10^^16/sec and 10^^14/sec which is the limit between x-rays and ‘visible’ light is not very much so the hypotheses that all photons have the same size is not far fetched. Further, frequencies below 10^^14/sec are ‘composite’ waves or radio waves and frequencies above 10^^16 are at the atomic level and might well be individual events.
P.S Gestalt means just what it does. Look it up in a dictionary and eigen values are the values for photon energy levels.
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SO, we have a tiny photon, emitted from an atom. In which direction does it go?
Is it random, in all directions?
My understanding of every book I have read on the subject is that one photon is produced during one decay and that the energy of the one photon is hf. Am I wrong in this? Your photons would, presumably, have to be a lot smaller than that if there are many per second, being emitted.
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The solution to a problem is much easier to see once the question becomes clear. In this thread, I think that McQueen is deeply troubled by the lack of a sound metaphyisical interpretation of modern physical theory. That is to say, we have math to describe what happens and it is very accurate, but we don't really know what those equations mean for reality. Metaphysics is the study of what is. Is a photon, the common term for a quanta of light, a particle or a wave, both or neither? What does it mean that light is quantized? What makes it quantized? Modern theory offers no attempt to answer these questions, although their answers could provide much future insight into physics and bear fruit to new mathematical models and physical theories. While I applaud any attempt, including McQueen's, to provide answers to these questions (thus showing an understanding of the principle that physical theories must not only be mathematically sound but must abide by the same logic as the rest of the universe), I do think that nothing I have read anywhere insofar has even scratched the surface of the problem.
McQueen's theory, as well as many others, try to determine whether a photon is a particle or a wave. They fail to clarify what is meant by quanta of light however. They assume, as many books such as "The Elegant Universe" state (in an attempt to explain something in simple terms that the author cannot explain accurately in complex terms), that light comes in material chunks. These pieces of light, are called photons. Therein lies the problem. Any new interpretation of quantum theory must discard all other flawed interpretations or risk being flawed itself. Digging past all of the mumbo-jumbo of frantic physicists and philosophers bending head-over-heels to make sense of a particle that isn't a particle, we see that photons-light quanta-arise from Planck's theory of black-body radiation. His theory is that light is absorbed and emitted from a perfect black-body with energy that comes in discrete quantities. This was an assumption he made to make his theory work, thinking that it had only mathematical validity, not physical truth. However, subsequent theories have shown that by assuming that energy of light comes in discrete units it is possible to construct successful theories. This lends some weight to the argument that light actually comes in discrete units of energy.
The name photons was coined to describe these units. The only difference between photons and joules or ergs is that you cannot have partial photons, only whole number quantities whereas you can have 1.5 joules or 9/15 ergs. From this interpretation, derived from the very fundamental assumption of Planck, we can see that light is not photons and photons are not light. Light is an electromagnetic wave and photons are units of energy. The work done to stand up can be described in photons (since they are analogous to joules). This is the fundamental nature of a photon.
As for light being a particle or a wave we must examine only the direct results of experiment and the products of generally accepted theories such as Maxwell's theory on electromagnetism (assumed to be true because of the large amount of experimental data in support of it). Light is a wave by Maxwell's theory, an oscillation in the EM field. It is easy enough to see where that idea comes from. However, light acts like a particle because it can be observed "moving" from point A to point B. I put moving in quotes because we don't actually see the light propagate; we see a start and end point. Particles move along paths that have start and end points and waves do not. There in lies the dilema.
Consider a ripple on the surface of a pond. If I drop a pebble straight down into the pond, a wave appears on the surface of the water. I know the start point (where the pebble hit the surface). Now, eventually I will see the reeds poking out of the pond several feet away sway. I have an end point. Now think of light. I cannot see the actual wave, only the emission and detection points. If the ripple on the pond were a light wave, I would see the pebble hit the surface of the water and then, after some time, I would see the reeds sway, without seeing the wave. It would seem that there was some particle that made a B-line for the reeds from the origin of the ripple but in reality I would know it was a wave because I knew that dropping a pebble in a pond makes a wave on the surface of the water.
It is hopefully apparent now that a knowledge of the origins of physical theories is necessary for developing metaphysical interpretations of them and, McQueen, although attempting to answer some of the fundamental philosophical conundrums of modern science is admirable, you cannot simply take a flawed theory (that of the photon being a material thing) and build upon it in hopes of creating an unflawed theory. You have to shove aside all the erroneous preconceived interpretations of reality and start at square one again-at the empirical facts.
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McQueen's theory, as well as many others, try to determine whether a photon is a particle or a wave. They fail to clarify what is meant by quanta of light however.
While I appreciate Mr. Andrew’s viewpoint that established science be given due respect. I cannot condone the fact that either he is deliberately misinterpreting what I have gone to great pains to explain or he has just not bothered to read what I have written, but has merely skimmed through the post and made his comments on the assumption that what I was saying was wrong.
With regard to the above point, quanta means discreteness, it means that every photon should have a discrete identity (energy) it is able to preserve. If Mr. Andrews, would care to look at the model of the photon that I have postulated he will soon come to see that this model does indeed satisfy the criteria of discreteness:
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In fact the Gestalt model of the photon performs so well that it can account for how a photon is able to preserve its identity (energy) so well even after traveling for billions of light years. In case Mr. Andrew is not aware of it, a photon’s energy is calculated by the equation E = hc/l where E stands for energy and l for wavelength, it is this energy that is preserved during a photon’s journey. For instance green light has a frequency of about 580 x 10^^14 MHz and a wavelength of 5.1 nm, this gives it an energy of about 2.4 x10^^2 eV.
Think about this: a photon of green light with a frequency of 580x10^^14 MHz is released by an electron revolving around an atom in a Galaxy 5 billion light years away. Five billion years later it is detected by a radio telescope on earth and it is still recognizably a green photon with an energy in the vicinity of 2.4 x 10^^2 eV although this energy might be slightly reduced (red-shifted). The great thing is that even while it has preserved its energy it still a wave, how does a photon manage to do this? I have put forward a viable theory explaining how this is possible and Mr. Andrews does not even seem to have have had the time to read about it !!
Whatever else QM claims to be able to do it has not made such a model, it has merely postulated that a photon has an infinite life-time, it is either absorbed or continues to exist, which is not much good when trying to form a model or to envision a photon.
About Max Planck Mr. Andrew has this to say:
(Mr. Andrew on light quanta)….This was an assumption he made to make his theory work, thinking that it had only mathematical validity, not physical truth.
Not true it is possible to detect individual photons with the naked eye. Photons are not just something that Max Planck dreamed up. He was an extremely conventional physicist and agonized over his theory, before publishing it.
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Why, McQueen, is it that the only formula you ever quote is E = hf? Everyone knows and is familiar with it and it doesn't need repeating every time.
Why should great distances be of huge significance? The only relevant thing about a photon traveling a great distance is that it is less and less likely to interact with an atom in a specific region on a sphere at that distance. The idea of 'getting weaker' just relates to this - the effective flux of photons through an area is less at a distance, that's all. The photon can have just as much energy wherever it chooses to interact with some system.
Mr Andrew has got it right when he distinguishes between a Science which is capable of predicting what will happen, as reliably as possible, and a meta Science which tries to give people a cosy feeling of understanding phenomena but may not be able to determine what is likely to happen.
Personally, I'd go for the system which produces results and put up with some nagging parodoxes. Physics has a certain amount of utility in this world. Without it we wouldn't be having this forum.
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SO, we have a tiny photon, emitted from an atom. In which direction does it go?
Is it random, in all directions?
My understanding of every book I have read on the subject is that one photon is produced during one decay and that the energy of the one photon is hf. Am I wrong in this? Your photons would, presumably, have to be a lot smaller than that if there are many per second, being emitted.
Prior to 1900 classical physicists, (…. there is nothing wrong with them, they won’t bite!) assumed the existence of an ether to explain the propagation of light. Presumably there was good reason for doing this, the idea of action at a distance might have been one of them. When, eventually, Maxwell’s theory on the propagation of electromagnetic radiation won wide-spread acceptance, there was no longer any need for the ether, it just got in the way. Maxwell’s theory showing that electromagnetic radiation consisted of alternating magnetic and electric fields that sustained each other obviated the need for an ether. This satisfactory state of things came to an end with the advent of QM, because the particle theory of light once again raised its head in a manner that could not be ignored. Yet instead of returning to the ether theory, (a wave might sustain itself a particle cannot! ) QM came up with a completely new and novel idea of a photon as being both a particle and a wave. The numerous proofs of this being so are to many to enumerate but let it be understood that there seemed to be enough proof to support the decision of wave-particle duality.
It is not necessary to go into the problems that the concept of wave-particle duality have caused. One result of this is that physics got more complicated, so much so that in an ironic turn of events, physicists themselves have now returned to something very much like an ether in their quest for the truth. One example of this is the polarization of a vacuum:
A photon is transformed into a ‘virtual’ electron-positron pair, which is annihilated and transformed again into a photon. The members of this pair during their life-time may obviously generate virtual photons and, consequently, new virtual electron-positron pairs and so on. As a result of this , the vacuum (read space) turns out not be “empty” but “filled” with virtual electric charges which must exert a screening influence on external;(real) charges.” From: Basic Concepts of Quantum Mechanics by L.V.Tarasov
The Gestalt Theory also makes use of an ether concept. This (ether) field consists of virtual photons that permeate the entire universe to the furthest galaxies and was formed and has been in existence since the Big Bang. The virtual photons that make up this field are of extremely low energy, so much so that they evade the Law of Conservation of mass and energy, through the Heisenberg Uncertainty Principle. They are thus completely permeable to matter, they pass through matter unchallenged. The photons of the virtual photon field are randomly oriented. However in the presence of a real photon the randomly oriented photons of the virtual photon field line up in the direction of propagation of the real photon, forming a line whose ends rest on infinity and the energy of the real photon travels along this line of aligned virtual photons at the speed of light. This happens in the same way that if a line of condensers is attached in series the energy of the first condensor, emerges at the last condensor in line intact, without distributing its energy to the intermediate condensers. Thus to answer your question. ]
A photon emitted by an electron does not travel randomly but along a line of virtual photons (Faraday’s lines of force). Photons of high frequency such as visible light and higher frequencies, are emitted by bound electrons and propagate along single lines of aligned virtual photons, photons of radio frequencies are composite photons and propagate in a similar manner although over a broad front.
Yes the emitted photon would be small in keeping with my earlier estimate of a few nanometers. For instance, green light has a wave length of 5.1 nm and a frequency of 5.8 x 10^^16Hz, so yes the photon size would have to be determined through frequency.
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Your post is full of surprises Sophicentaur! By all means support Mr. Andrew, but I hope you don’t mind me pointing out a few anomalies in the observations you have made?
The only relevant thing about a photon traveling a great distance is that it is less and less likely to interact with an atom in a specific region on a sphere at that distance. The idea of 'getting weaker' just relates to this - the effective flux of photons through an area is less at a distance, that's all. The photon can have just as much energy wherever it chooses to interact with some system.
A particle although it does not travel at the speed of light, does according to Newton retain its original momentum if there is no opposing force to stop it. Thus a particle would retain its energy (momentum) over long distances in space. From what you state in your post
the photons start of as a group of particles and get further and further apart as the distance over which they travel increases? That is all very well but if the photons did start of as a group of particles they would be so widely separated by the time they had been traveling for a couple of billion years (especially if they were observing the inverse square law) that the distances between them would be so great that they would miss the Milky Way altogether!
In fact photons (light) does not travel like that, it travels as an interconnected group if this were not so it would be impossible to detect them at such distances. Frankly I do not see what you were trying to achieve with your post. At least my post did offer a viable solution to the problem, without resulting in any ‘nagging paradoxes.’
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Nowhere in my post do I say that a photon is a particle. It, so clearly, isn't. There is no possible Newtonian mechanics argument which can be used because we are not dealing with particles.
To quote McQueen, in a much earlier post, "you must open your mind"; I did say that there is a difficult step in the argument but that the idea of quantum entanglement allows it. Newtonian ideas only work for Newtonian items. There must be something you have missed in what I have written.
It is still not clear whether a photon consists of one or several of the pretty blue things. If it consists of many, then why does it not take fractional values (would this involve integer fractions?)? Why can't a system just use a bit of a photon and let another system have the rest?
I thought that the evidence is that a photon, resulting from an energy change, maintains its energy until it interacts, totally, somewhere else. This would suggest that a photon would only consist of one 'blue object'.
Tell me again what the viable solution was? I must have missed it.
In fact photons (light) does not travel like that, it travels as an interconnected group
You have, recently, quoted the Einstein photoelectric effect, so you will have read around the subject. You will know that it involves just one photon interacting with a system at a time. In low light levels, an image intensifier shows flashes which correspond to individual photons (that is the current model). Light from a distant star, could be arriving here at the rate of one photon per year - an image intensifier would 'see' this photon, if it were switched on and in the right place; the photon wouldn't need its mates to be nearby for this to happen. So why do you insist that photons need to travel in groups? None of the above examples seem to involve this idea. Have you an example which does?
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You all seem to have forgotten that a red shifted photon from a distant galaxy HAS lost energy the cosmic microwave background was as bright as the sun and about the same colour when it happened but now the photons are much less energetic radio waves and its only as bright as the moon.
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I quite enjoyed reading the tongue in cheek manner of your post. Taking one of the trickier questions first:
Light from a distant star, could be arriving here at the rate of one photon per year - an image intensifier would 'see' this photon, if it were switched on and in the right place; the photon wouldn't need its mates to be nearby for this to happen. So why do you insist that photons need to travel in groups? None of the above examples seem to involve this idea. Have you an example which does?
Electromagnetic radiation without exception, and this includes x-rays, gamma rays as well as visible light and radio waves, follows the inverse square law, that means that it is impossible for an individual photon from a distant star to arrive at the rate of one photon per year. If light from a distant star was detected on earth it would be detected simultaneously at every point on the earth and probably in the entire solar system also, there is no question of an individual photon making it on its own. If one photon is detected then photons of the same intensity would be detected everywhere else on earth at exactly the same time.
I am surprised that with your scientific background and obvious competence in mathematics you could have made such a mistake. This is one of the problems with a purely mathematical approach to questions in physics, if you are not able to verbalise your picture of what is taking place, the tendency is to get lost in abstractions. Because it is not always easy to picture things in terms of pure mathematics.
As regards your comment on the photo-electric effect:
You have, recently, quoted the Einstein photoelectric effect, so you will have read around the subject. You will know that it involves just one photon interacting with a system at a time. In low light levels, an image intensifier shows flashes which correspond to individual photons (that is the current model).
There is no doubt at all that Einstein was right about this. The mistake is in thinking that it is individual photons that were emitted, this would go against the inverse square law, the whole of the target area was flooded, assuming monochromatic light, with photons of the same energy, in some instances electrons were ejected and in others not. Still it is difficult to say, in spite of Planck’s constant that only one photon was absorbed by each electron! Take ultraviolet light which has a frequency of approx 10^^16 or a single photon is emitted in 10^^-16/th of second ! Even with today’s equipment it would not be possible to accurately time such an event. If the frequency of ultraviolet light is true, and there is no reason to believe that it is not. Then each atom would be in a position to absorb many photons in a fraction of a second. Or am I missing something here!
As regards clarifications on my theory I will get back to you later.
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You all seem to have forgotten that a red shifted photon from a distant galaxy HAS lost energy the cosmic microwave background was as bright as the sun and about the same colour when it happened but now the photons are much less energetic radio waves and its only as bright as the moon.
Here again we have another incredible misconception. I have read many great posts by Soul Surfer, so it is hard to credit him with making such an error. Think about it if the photon’s in question were red shifted from the color of the sun ( red/yellow/ gold) to radio-waves how would we know what color (energy) they were to begin with? When a photon is red shifted it is still the same color! It is only by comparing spectral lines of one color with red-shifted spectral lines of the same color that we can tell that they have been red-shifted. If the photons were to change color all together how would you know that they have been red shifted, what would you use for comparison? Or am I wrong about this? As far as I know a red shift corresponding to 16% signifies a source two billion light years.
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If the photons were to change color all together how would you know that they have been red shifted, what would you use for comparison?
This is such an ignorant question that it demonstrates appalling ignorance of the whole of this subject. How do you suppose a red shift is apparent? It's a fundamental tool of cosmology.
Try reading around the subject.
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You are very wrong McQueen! the cosmic microwave background photons were emitted as light and their enegy was plancks constant times the frequency. The expansion of space as they travelled has sapped their energy and now their frequency is much lower andin the microwave region so theur individual energies are much lower however there are still exactly the same number of photons.
You are also wrong about the detection of individual photons from a very dim source this depends on the effective detector area and a dim source may produce one photon per square pmeter per hour in a particular direction so if you had another detector the same size somewhere else it would also detect one photon per hour but not the same photon at the same time. If it was one per year one of the detectors may respond in one particular hour but you might have to wait more than a year (by statistics) for the other detector to respond.
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This is such an ignorant question that it demonstrates appalling ignorance of the whole of this subject. How do you suppose a red shift is apparent? It's a fundamental tool of cosmology.
Try reading around the subject.
I am at a loss and have to look to you for enlightenment on the subject: The question was:
If the photons were to change color all together how would you know that they have been red shifted, what would you use for comparison?
The next statement was the one by soulsurfer:
You are very wrong McQueen! the cosmic microwave background photons were emitted as light and their enegy was plancks constant times the frequency. The expansion of space as they travelled has sapped their energy and now their frequency is much lower andin the microwave region so theur individual energies are much lower however there are still exactly the same number of photons.
This is surely a theoretical construction, it might be true or not, I can't say. What I was talking about was the practical way in which the red-shift is used to determine a sources distance. As far as I know it is the same color (energy) only red-shifted by some per centage. In anycase I have asked Sophie Centaur the same question hopefully he will be forthcoming. I have given my version of it let's see what comes of it.
Common sense tells us that if you receive a photon of a certain energy, then you can only compare it if it still has roughly the same identity. For instance if the colour of the photon was blue but it was a different frequency and energy from the blue received from a nearby star, then you could say, yeas. This photon has travelled so far. But if the blue has turned into microwave frequencies how could you say it was blue in the first place? Do you follow my reasoning or am I missing something?
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You are also wrong about the detection of individual photons from a very dim source this depends on the effective detector area and a dim source may produce one photon per square pmeter per hour in a particular direction so if you had another detector the same size somewhere else it would also detect one photon per hour but not the same photon at the same time. If it was one per year one of the detectors may respond in one particular hour but you might have to wait more than a year (by statistics) for the other detector to respond.
Theoretically if the distance between the source and the detection area were small and it was possible to time the emission of a photon according to its frequency so that only one was released it might be possible to detect a single photon. But in other circumstances, if for instance you have a very dim light source on for several minutes or hours there would be absolutely no truth in it whatsoever. Any source of electromagnetic radiation follows the inverse square law. How do you think we are able to receive radio transmission from Voyager 1, about six billion miles distant from the earth ?
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Electromagnetic radiation without exception, and this includes x-rays, gamma rays as well as visible light and radio waves, follows the inverse square law, that means that it is impossible for an individual photon from a distant star to arrive at the rate of one photon per year. If light from a distant star was detected on earth it would be detected simultaneously at every point on the earth and probably in the entire solar system also, there is no question of an individual photon making it on its own. If one photon is detected then photons of the same intensity would be detected everywhere else on earth at exactly the same time.
Wrong. The computation of the intensity can tell you how is the *probability* of detecting a photon, not where it will be detected; you will have the same intensity and so the same probability on a huge spherical surface centered in the star, but this DON'T mean that you will detect light in every point of that suface.
Welcome in the modern physics world!
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Theoretically if the distance between the source and the detection area were small and it was possible to time the emission of a photon according to its frequency so that only one was released it might be possible to detect a single photon. But in other circumstances, if for instance you have a very dim light source on for several minutes or hours there would be absolutely no truth in it whatsoever. Any source of electromagnetic radiation follows the inverse square law. How do you think we are able to receive radio transmission from Voyager 1, about six billion miles distant from the earth ?
It's only a matter of probability. The low intensity doesn't tell you that you will have a little part of a photon, but only that you will have to wait longer to detect one. Have you ever heard of "Taylor's experiment"? (1909!)
http://www.seas.harvard.edu/brenner/taylor/physic_today/taylor.htm
Interference fringes by feeble light
We began our tour of Taylor’s research by discussing his first scientific paper, which was published in 1909. This was his only paper that was not classical physics, but it nonetheless bore the experimental characteristics that were to appear throughout his later work. At the request of J. J. Thomson, Taylor performed an experiment (in the children’s room of his parent’s house!) to determine whether there was a qualitative change in a diffraction pattern when the intensity of the light is reduced greatly.3 Taylor indicates that Thomson believed that there would be a change in the pattern. Taylor took photographs of the shadow of a needle, varying the intensity of light by shielding the light source with smoked glass screens. When decreasing the intensity he increased the exposure time to keep the total amount of light on the photograph constant. The longest experiment took three months, corresponding to the intensity of a candle more than a mile away; some of the experiments even took place while Taylor was on a yachting trip. Taylor observed no change in the diffraction pattern, wrote a two-page paper describing this result, and then dropped this line of research.
http://spiff.rit.edu/classes/phys314/lectures/dual3/dual3.html
http://en.wikipedia.org/wiki/Geoffrey_Ingram_Taylor
His first paper was on quanta showing that Young's slit diffraction experiment produced fringes even with feeble light sources such that less than one photon was present at a time.
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In explanation of the above two posts see this site (http://hyperphysics.phy-astr.gsu.edu/hbase/astro/hubble.html#c3) on the Hubble law and red shifts. I entered in a value of 500nM and got 550 nm as infinity? Can you explain?
P.S. See table at bottom of page where you can enter values!
If I enter 500 nm as first value and 550 nm as second (red-shifted) value, I get 0.095022624434c as recessional speed of the galaxy.
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RED SHIFT: HOW WE KNOW IT'S HAPPENED
You know that each element has its characteristic spectrum of emission lines; their frequencies are related to each other by characteristic ratios- predicted by QM and confirmed in many experiments. The Cosmological Principle says that Physics is the same everywhere (if not, then what hope is there?) so we assume that a Hydrogen atom does the same thing, even in a distant galaxy.
Light from distant sources contains these patterns of lines, corresponding to the elements on Earth BUT their frequencies are not those of atoms here. Their frequency is nearly always lower. The amount by which their frequency differs from what we would expect is their red shift. A few exhibit blue shift - they must be moving towards us.
It still amazes me that anyone can have opinions about deep matters to do with Physics and Cosmology if they don't know something a basic as this.
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Reply with quote
RED SHIFT: HOW WE KNOW IT'S HAPPENED
Thank you ! I was wrong !
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The red shift is understandable because we are looking at the spectrum of the object and not one single colour of light. The spectra of stars and galaxies are highly structured and contain a great deal of information about the composition of the stars and galaxies together with the conditions (pressure and temperature) when they were emitted they are almost as individual as fingerprints. When red shift occurs one sees all the wavelengths of all the frequencies in the spectrum changed according to exactly the same rule and so it is easy to identify by how much the spectrum has been red shifted.
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People interested in Doppler effect of light could also watch lesson 23 of these movies:
http://ocw.mit.edu/OcwWeb/Physics/8-01Physics-IFall1999/VideoLectures/index.htm
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Reply with quote
RED SHIFT: HOW WE KNOW IT'S HAPPENED
Thank you ! I was wrong !
Spoken like a true gent.
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Not been around for a while so hi to all! [;D]
Regarding the red shift.
Has anyone read the lectures by Alexander Franklin Mayer?
GTR intro: A New Gravitational Effect. L1: A Correction to the Gravitational Model. L2: The Many Directions of Time.
Fairly large pdf files though and sorry I don't have the link [:I], you should find him in a search though.
He has some interesting ideas about the red shift, gravity, black holes, dark matter etc.
A long read and much too difficult (math) for me to explain.
Not sure how he is regarded in the physics world.
Hope this post was appropriate given the context. [:)]
Bee
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If I enter 500 nm as first value and 550 nm as second (red-shifted) value, I get 0.095022624434c as recessional speed of the galaxy.
I entered 12000 Mly and got a wavelength of 656 nm red shifted to 2377.11 nm.
I have been thinking about the Doppler red-shift. All waves exhibit, including the electromagnetic, the Doppler effect. It is really quite a weird phenomenon. If you are on a train approaching a station on which two men are standing, one on the near end of the platform and the other on the further end, and the train driver blows the whistle, something extraordinary happens. You, on the train hear the original frequency of the whistle as it is ‘supposed’ to sound, the man on the nearer side of the platform hears the whistle at a slightly higher frequency as the train approaches the platform and the man on the further side of the platform hears a lower frequency as the train recedes into the distance. Which of these frequencies is the ‘real’ one. The answer of course is that all three people hear a ‘real’ sound and all three frequencies exist according to where the person happens to be located.
What is amazing about this, is that the speed at which these various frequencies are being heard remains constant! Only the frequency of the sound (or light) is varied.
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If I enter 500 nm as first value and 550 nm as second (red-shifted) value, I get 0.095022624434c as recessional speed of the galaxy.
I entered 12000 Mly and got a wavelength of 656 nm red shifted to 2377.11 nm.
I have been thinking about the Doppler red-shift. All waves exhibit, including the electromagnetic, the Doppler effect. It is really quite a weird phenomenon. If you are on a train approaching a station on which two men are standing, one on the near end of the platform and the other on the further end, and the train driver blows the whistle, something extraordinary happens. You, on the train hear the original frequency of the whistle as it is ‘supposed’ to sound, the man on the nearer side of the platform hears the whistle at a slightly higher frequency as the train approaches the platform and the man on the further side of the platform hears a lower frequency as the train recedes into the distance. Which of these frequencies is the ‘real’ one. The answer of course is that all three people hear a ‘real’ sound and all three frequencies exist according to where the person happens to be located.
What is amazing about this, is that the speed at which these various frequencies are being heard remains constant! Only the frequency of the sound (or light) is varied.
McQueen, you really amaze me. You propose a new theory of photons and you discover NOW sound Doppler effect! Do you want to pull ours leg?
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McQueen, you really amaze me. You propose a new theory of photons and you discover NOW sound Doppler effect! Do you want to pull ours leg?
No, I think it is quite fascinating that whether you are talking about sound doppler effect or electromagnetic doppler effect, it is possible to have so many views of the same thing.
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Before you hold forth on a particular view, it might be a good idea to get a bit more knowledge, perhaps?
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One of the strengths of the Naked Scientist Forum is it’s excellence in the field of astrophysics, and rightly so given the number of members who have either qualified in this subject or are otherwise interested. What surprises me is that not a single forum member has come forward to elucidate the slightly erroneous impression that members have been left with on this thread with regard to the red shift. The impression that lingers with regard to the red shift is that light as it travels over enormous distances, gradually loses energy resulting in longer and longer wave lengths, so that eventually, one presumes, that there will be nothing left. The Hubble theory of the red shift is in fact exactly the opposite. Hubble theorists, which includes the majority of astrophysicists, believe, that light or electromagnetic radiation, retains its energy (identity) almost indefinitely, and the red shift only occurs if the source is moving away from a given location. (f it is moving towards the location a blue shift occurs.) This seems to make sense since then the Doppler effect becomes a part of Einstein’s space time continuum. Therefore to sum up, the Doppler effect only occurs if the source happens to be moving relative to a given location. Any comments ?
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When supernatural phenomena clearly do not exist in the world we live in.
Can you provide definitive proof of that statement? Or is it just a statement of your theory of how things are?
I have personally experienced supernatural phenomena on more than 1 occasion so, as far as I am concerned, your statement is false.
The vast majority of scientists will stick to their guns (or, as you phrased it, be conservative) until something better comes along. If that were not the case then there would be no development. Everyone would be out looking for new things before existing ideas were taken further. There have been a few "quantum leaps" in understanding (such as provided by Newton, Galileo, Einstein, Planck, Dirac, Feynman, etc), but most progress comes from working within an existing framework to gain a better understanding of it and progressing along lines that seem to provide the right answers.
Take Quantum Electro-Dynamics (QED). It is the most tested, consistent and predictively accurate field of physics ever developed (some experiments give an accuracy of 1 part in a trillion). Yet the workings of it are so counter-intuitive as to be almost supernatural in themselves. Borrowing energy from nothing? Borrowing it from the future? That doesn't sound very scientific, does it. But the point is that IT WORKS!
You will not find a scientist anywhere who would say without a caveat that "This is how things are". They all accept that our knowledge is incomplete but that currently-accepted theories accurately predict events in the real world.
Yes, there are holes in existing theories. That is why scientists are looking at Quantum Loop Gravity, extra dimensions, and many other theories. Until a complete TOE is developed, we'll just have to accept that things are as they are because they are as they are.
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I have personally experienced supernatural phenomena on more than 1 occasion so,
Are you referring to 'ectoplasmic phenomena' or to results of scientific experiments which weren't what you expected? There is a big difference between the two.
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I have personally experienced supernatural phenomena on more than 1 occasion so,
Are you referring to 'ectoplasmic phenomena' or to results of scientific experiments which weren't what you expected? There is a big difference between the two.
Neither.
I was talking to a South African friend of mine who mentioned her friend in Durban. I proceeded to describe the friend's apartment, what could be seen out of the window and even what car she had (I was wrong on the car. I said it was a silver BMW when it was, in fact, a silver Audi). I even had an argument with my friend about the colour of the 3-piece suite. I insisted it was a maroon colour, but my friend said I was wrong and that her friend's suite was, in fact, grey. A couple of days later my friend phoned her friend and - guess what - she'd bought a new 3-piece suite; a maroon coloured 1.
I've done similar things, but that example is the most striking.
I promise you this is all true. Believe it or not, as you please.
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The experiences which you describe as supernatural are very much 'personal' and open to different interpretations. I am a great believer in statistical significance tests with measurements before I can bring myself to believe that an event is anything but random.
The oddities associated with quantum physics are a lot more 'concrete' in as far as they can be repeated in many different experiments and the resulting probability distributions, for example, fit the pattern.
Duality doesn't have to be a problem as long as we don't insist on bringing too much classical baggage with us into the subject.
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I wasn't saying that we need to look to the supernatural for explanations. I don't think we should. I think there's probably a rational explanation for the sort of things I've experienced but we just don't know what those explanations are yet.
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I was talking to a South African friend of mine who mentioned her friend in Durban. I proceeded to describe the friend's apartment, what could be seen out of the window and even what car she had (I was wrong on the car. I said it was a silver BMW when it was, in fact, a silver Audi). I even had an argument with my friend about the colour of the 3-piece suite. I insisted it was a maroon colour, but my friend said I was wrong and that her friend's suite was, in fact, grey. A couple of days later my friend phoned her friend and - guess what - she'd bought a new 3-piece suite; a maroon coloured 1.
I've done similar things, but that example is the most striking.
I promise you this is all true. Believe it or not, as you please.
You don't know how much I would like to meet you... [:)]
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I was talking to a South African friend of mine who mentioned her friend in Durban. I proceeded to describe the friend's apartment, what could be seen out of the window and even what car she had (I was wrong on the car. I said it was a silver BMW when it was, in fact, a silver Audi). I even had an argument with my friend about the colour of the 3-piece suite. I insisted it was a maroon colour, but my friend said I was wrong and that her friend's suite was, in fact, grey. A couple of days later my friend phoned her friend and - guess what - she'd bought a new 3-piece suite; a maroon coloured 1.
I've done similar things, but that example is the most striking.
I promise you this is all true. Believe it or not, as you please.
You don't know how much I would like to meet you... [:)]
I knew you were going to say that [:D]
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Wot about my question Luv?????? Does light fade with distance or only with the doppler effect??????
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Wrong. The computation of the intensity can tell you how is the *probability* of detecting a photon, not where it will be detected; you will have the same intensity and so the same probability on a huge spherical surface centered in the star, but this DON'T mean that you will detect light in every point of that suface.
Welcome in the modern physics world!
You are way wrong man. Space exploration, especially the Voyagers would not have been possible with your crummy theory. If you want to argue get out your pen and pencil!!!
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Wrong. The computation of the intensity can tell you how is the *probability* of detecting a photon, not where it will be detected; you will have the same intensity and so the same probability on a huge spherical surface centered in the star, but this DON'T mean that you will detect light in every point of that suface.
Welcome in the modern physics world!
You are way wrong man. Space exploration, especially the Voyagers would not have been possible with your crummy theory. If you want to argue get out your pen and pencil!!!
I think you'll find that lightarrow knows a bit more about this than you do.
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Wrong. The computation of the intensity can tell you how is the *probability* of detecting a photon, not where it will be detected; you will have the same intensity and so the same probability on a huge spherical surface centered in the star, but this DON'T mean that you will detect light in every point of that suface.
Welcome in the modern physics world!
You are way wrong man. Space exploration, especially the Voyagers would not have been possible with your crummy theory. If you want to argue get out your pen and pencil!!!
What does space exploration have to do with it?
The fact is that no-one can tell you where the photon will be detected.
P.S.
It's not my theory, it's called "Quantum Mechanics". (I wish it was, my theory! [:)])
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You don't know how much I would like to meet you... [:)]
I knew you were going to say that [:D]
Oh my! [:o]
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Wrong. The computation of the intensity can tell you how is the *probability* of detecting a photon, not where it will be detected; you will have the same intensity and so the same probability on a huge spherical surface centered in the star, but this DON'T mean that you will detect light in every point of that suface.
Welcome in the modern physics world!
You are way wrong man. Space exploration, especially the Voyagers would not have been possible with your crummy theory. If you want to argue get out your pen and pencil!!!
What does space exploration have to do with it?
The fact is that no-one can tell you where the photon will be detected.
P.S.
It's not my theory, it's called "Quantum Mechanics". (I wish it was, my theory! [:)])
If it was your theory, you could explain it all to me. And I'd be your agent. Reasonable fees - only 30% [:D]
For any space exploration mankind has done so far, Newtonian physics had served perfectly adequately. If I remember correctly, Newtonian physics shows an error of only 10 metres in the position of the moon.
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If it was your theory, you could explain it all to me. And I'd be your agent. Reasonable fees - only 30% [:D]
Ok, but with this condition: it would remain 30% even after I've explained it all to you! [;)]
For any space exploration mankind has done so far, Newtonian physics had served perfectly adequately. If I remember correctly, Newtonian physics shows an error of only 10 metres in the position of the moon.
Didn't know it!
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Alberto - there has been an on-going experiment measuring the exact position of the moon using lasers reflecting off the mirrors left there by Apollo missions. After years of measurement it has been established that the moon is not where it should be in its orbit according to Newtonian mechanics.
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Alberto - there has been an on-going experiment measuring the exact position of the moon using lasers reflecting off the mirrors left there by Apollo missions. After years of measurement it has been established that the moon is not where it should be in its orbit according to Newtonian mechanics.
Ah, yes, but I didn't know they could reach such a precision!
Thanks.
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There is some new work that may explain what photons are and why they have previously been so difficult to identify. The worked was reviewed by Hans Peter Duerr (Director Emeritus Max Planck Institute for Physics, and Heisenberg protege) prior to any talks or papers. His assessment - the mathematics are correct ... what remains to be determined is the interpretation.
It is possible that the difficulty with conceptualizing photons goes all the way back to the origins of quantum theory. As Sherlock Holmes indicated, if you cannot solve the mystery you must go back and test all of your assumptions. Once you have done so you will eventually find the answers you are seeking.
If we go back to the origins of quantum theory we find that Planck ORIGINALLY worked on electromagnetic theory with energy, an energy constant (energy/EM oscillation), measurement time (of the EM irradiation) and frequency (osc/sec). His original relationship was thus E = energy constant X measurement time X frequency.
When he wrote his famous paper deriving the formula for black-body radiation, he had to resort to the use of Boltzmann's statistical methods (Planck was not very fond of Boltzman) and this in turn caused him to multiply his original energy constant and measurement time into the single value "h" (which by the way caused his measurement time variable to become fixed at the value of one second).
The product of energy and time is called "action" so Planck's constant "h" was and is referred to as an action constant. Planck didn't really like it at first as he had an energy constant in mind, not an action constant. His action constant "h" produced the odd result that the fundamental particle of light - the photon - came in an infinite variety of energies, rather than having a constant defining energy ... a defining constant characteristic such as the charge on an electron. The units didn't balance either because the "oscillations" in frequency (osc/sec) were unbalanced.
But the number worked and people started using his equation so he went with it.
If we restore his original formula we have E = E/osc X measurement time (sec) X frequency (osc/sec). Units balance and total energy can be determined. If you irradiate for 2 seconds instead of one you measure twice as much energy. The energy constant from Planck's original formulation turns out to be the energy of a single EM oscillation. The energy is conserved over time and space, and appears to be therefore the true quantum of energy for EM waves (unlike the infinitely variable photon).
Because the units did not balance in Planck's condensed E = hf, the engineers and scientists got together back in the thirties and officially changed the nomenclature for frequency from osc/sec to sec-1. That got rid of the pesky oscillations hanging out of the equation and everything balanced.
So far so good, but it was incomplete mathematical notation and that never helps anything. Kind of like describing your miles per hour speed as just hour-1. You would have to start putting in a lot of fudge factors to account for the fact that it was miles and not kilometers or yards you were measuring. Same thing happened in quantum mechanics. More and more fudge factors had to be brought because the foundational quantum equation was abbreviated and incomplete in a mathematical sense.
A lot of the problems in quantum mechanics go away if one uses Planck's original and complete quantum formula. Take the photon for example. Depending on the frequency the energy of the photon changes. There is no constancy for it and a lot of "fudge factor" type theories must be used to explain this anomaly. If we use Planck's original relationship, however, the paradox disappears. We have a constant energy per oscillation EM radiation (6.626 x10-34 J/osc. If the frequency is 10,000 Hz, and we measure the EM energy for one second as is typical, we end up with 6.626 X 10-30 joules of energy. If we change the frequency to 300,000 Hz, and measure for the standard one second, we get 19.9 X 10-29 joules.
When you play around with the numbers, you eventually realize that when you measure more waves, you get more energy. The "photon" is stuck with that fixed measurement time of one second, instead of what should be a measurement variable. And so however many oscillations there are in frequency - osc/sec - get added up by Planck's condensed quantum formula. This yields energy that keeps changing with frequency.
Since the energy constant is conserved across time and space, it is a much more likely candidate for elementary particle of light. What it all boils down to is that the photon may be an artifact of an incorrect assumption in the origins of quantum theory. It may actually be a collection of elementary light particles, and not an elementary particle itself.
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There is some new work that may explain what photons are and why they have previously been so difficult to identify.
I don't see any problem identifying photons or any reason to say that they're hard to explain. In fact I've always thought of them as very simple to understand.
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It may actually be a collection of elementary light particles, and not an elementary particle itself.
That would raise a few questions.
1. Would this imply that the quantum of EM energy was smaller than a photon?
2. Might it be that such light particles could occur only in discrete collections?
3. If it’s “yes” to question 2, would the photon – although not elementary – still count as the quantum of light?
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It may actually be a collection of elementary light particles, and not an elementary particle itself.
That would raise a few questions.
1. Would this imply that the quantum of EM energy was smaller than a photon?
2. Might it be that such light particles could occur only in discrete collections?
3. If it’s “yes” to question 2, would the photon – although not elementary – still count as the quantum of light?
Can you give me context for where I said that? This thread is long and very old, so I'm not sure I recall what I was talking about... :p
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Sorry JP! I think I must have had a mental aberration. I can’t find the quote in this thread, nor, at the moment, can I find it anywhere else. I guess I'm the one who doesn't know what I'm talking about. [:I]