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Author Topic: Photons and why they're so hard to explain  (Read 30926 times)

lyner

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Re: Photons and why they're so hard to explain
« Reply #25 on: 07/12/2007 19:51:22 »
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.
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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.
« Last Edit: 07/12/2007 19:55:43 by sophiecentaur »
 

lyner

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Re: Photons and why they're so hard to explain
« Reply #26 on: 07/12/2007 19:55:02 »
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!
 

Offline McQueen

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Re: Photons and why they're so hard to explain
« Reply #27 on: 07/12/2007 19:56:55 »
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.
 

Offline JP

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Re: Photons and why they're so hard to explain
« Reply #28 on: 07/12/2007 20:00:09 »
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)." 
 

Offline McQueen

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Re: Photons and why they're so hard to explain
« Reply #29 on: 07/12/2007 20:02:17 »
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.
 

Offline McQueen

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Re: Photons and why they're so hard to explain
« Reply #30 on: 07/12/2007 20:09:37 »
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???
 

Offline JP

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Re: Photons and why they're so hard to explain
« Reply #31 on: 07/12/2007 20:24:16 »
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.
 

lyner

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Re: Photons and why they're so hard to explain
« Reply #32 on: 07/12/2007 23:52:32 »
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.
 

Offline McQueen

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Re: Photons and why they're so hard to explain
« Reply #33 on: 08/12/2007 08:17:29 »
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:



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.


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.
« Last Edit: 08/12/2007 08:24:49 by McQueen »
 

lyner

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Re: Photons and why they're so hard to explain
« Reply #34 on: 08/12/2007 10:33:00 »
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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".
 

Offline McQueen

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Re: Photons and why they're so hard to explain
« Reply #35 on: 08/12/2007 11:07:07 »
]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.
 

lyner

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Photons and why they're so hard to explain
« Reply #36 on: 08/12/2007 14:15:17 »
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.
« Last Edit: 08/12/2007 14:20:17 by sophiecentaur »
 

Offline Mr Andrew

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Photons and why they're so hard to explain
« Reply #37 on: 08/12/2007 17:41:59 »
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.
 

Offline McQueen

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Photons and why they're so hard to explain
« Reply #38 on: 09/12/2007 00:45:42 »
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:



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.


« Last Edit: 09/12/2007 00:48:48 by McQueen »
 

lyner

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Photons and why they're so hard to explain
« Reply #39 on: 09/12/2007 01:01:48 »
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.
 

Offline McQueen

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Photons and why they're so hard to explain
« Reply #40 on: 09/12/2007 01:56:39 »
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.
« Last Edit: 09/12/2007 03:12:11 by McQueen »
 

Offline McQueen

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Photons and why they're so hard to explain
« Reply #41 on: 09/12/2007 03:05:34 »
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.’
« Last Edit: 09/12/2007 03:09:42 by McQueen »
 

lyner

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Photons and why they're so hard to explain
« Reply #42 on: 09/12/2007 13:21:39 »
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.

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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?
 

Offline Soul Surfer

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Photons and why they're so hard to explain
« Reply #43 on: 09/12/2007 23:20:00 »
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.
 

Offline McQueen

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« Reply #44 on: 10/12/2007 06:29:04 »
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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« Reply #45 on: 10/12/2007 06:48:11 »
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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« Reply #46 on: 10/12/2007 08:01:38 »
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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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« Reply #47 on: 10/12/2007 09:14:08 »
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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Photons and why they're so hard to explain
« Reply #48 on: 10/12/2007 13:35:22 »
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?
« Last Edit: 10/12/2007 13:44:14 by McQueen »
 

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Photons and why they're so hard to explain
« Reply #49 on: 10/12/2007 13:51:55 »
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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