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#7097 06/02/06 06:04 PM
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What is the mass of photon ?
Its true that photon hasn't any mass?
Tks.


mfm
.
#7098 06/02/06 07:02 PM
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It must be true. If it had mass it would mean that it had inertia; which, in turn, means that there must be an inertial reference frame within which the photon will be stationary. This is not possible in terms of Einsten's theory of special relativity. I put my bet on Einstein.

#7099 06/02/06 08:54 PM
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Johnny Boy defending the conventional scientific view? Wow, I'm impressed!


As shown in this article the experimental limits on the photon mass aren't as strong as previously thought.

#7100 06/02/06 09:54 PM
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Quote:
Originally posted by Count Iblis II:
Johnny Boy defending the conventional scientific view? Wow, I'm impressed!


As shown in this article the experimental limits on the photon mass aren't as strong as previously thought.
Thank you for the compliment. In my mind mass responds to inertia and also energy. So it has to be the potential energy of a stationary particle relative to its proper inertial reference frame. When solving the Schroedinger equation for a free electron it is assumed in textbooks that it has no potential energy. Delocalised waves are then generated that have to stretch over the whole universe requiring a special stationary inertial reference frame: this violates Einstein. A stationary free electron has mass-energy because its potential energy is that of the ground-state of a harmonic oscillator; i.e it experiences a stable minimum potential energy. Thus if I am correct that mass means stable equilibrium relative to the proper inertial reference frame of a particle, then a photon cannot have mass.

#7101 06/03/06 08:28 AM
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Very thanks, i undestand almost all your says, althought i dont understand what this means. "
its potential energy is that of the ground-state of a harmonic oscillator "

Its possible to explain a little bit more to an amateur ?

And another question, if you say the mass photon dont exist "It must be true, the, " is there another scientifics or theorys that maintain its opposite, that the photon mass exists, or isn't = 0 ?


mfm
#7102 06/03/06 12:27 PM
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manfermef, in his second posting, Johnny Boy is again playing his usual role in this forum, i.e. to write about his personal theories.

Joohnny Boy somehow deduced that the photon must be massless, but he didn't use any of the photon's properties in his reasoning. So, his argument must be wrong, because you could replace ''photon'' by any other particle in his argument and then you would have to conclude that all particles are massless.

The Z-boson is a particle that is very similar to the photon. But it is very massive. Special relativity just states that theories must be symmetrical under so-called Lorentz transformation. A massive photon would not violate special relativity at all.

#7103 06/03/06 04:02 PM
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Well explained Count!!

Then I sum up that isnt sure the photon is whithout any mass.
At least that its not demonstrate by science.

Its all ok?


mfm
#7104 06/03/06 05:23 PM
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Quote:
Originally posted by Count Iblis II:
manfermef, in his second posting, Johnny Boy is again playing his usual role in this forum, i.e. to write about his personal theories.

Joohnny Boy somehow deduced that the photon must be massless, but he didn't use any of the photon's properties in his reasoning. So, his argument must be wrong, because you could replace ''photon'' by any other particle in his argument and then you would have to conclude that all particles are massless.
I am afraid that Count Iblis II is displaying his ignorance of Galileo's statement of relativity that finally led to Newton's first law. I still think that one should first truly understand Newton's mechanics before spouting nonsense about the physics that came after it. Any "particle" can have two types of energy: kinetic and potential. Without kinetic energy it can only have potential energy. Mass is energy and within the inertial reference frame that a particle with mass is stationary its "rest mass" must represent its lowest energy state. But it is not kinetic energy because the particle is stationary within its proper inertial reference frame. Even Einstein's special theory of relativity tells you that the rest mass is NOT kinetic energy. So it must be potential energy which manifests when the particle is at rest within its inertial reference frame. A photon can never be at rest within any inertial reference frame. So it cannot have potential energy which can be ascribed to mass. What is illogical about this argument Count Iblis II. Or do you not believe that the rest mass is energy? Where do my "personal theories" come in? The argument is based on physics that has been accepted as correct (at low speeds) for more than 300 years, as well as Einstein's special theory of relativity which is now more than 100 years old!!!


Quote:
Originally posted by Count Iblis II:
The Z-boson is a particle that is very similar to the photon. But it is very massive. Special relativity just states that theories must be symmetrical under so-called Lorentz transformation. A massive photon would not violate special relativity at all.
Yes, but in contrast to a photon the Z-boson has a rest mass and can thus be stationary relative to its proper reference frame; or what does the term "rest mass" tels you Count Iblis II? It seems to me that YOU are rather having you own theories; which are at variance with Newton's laws and Einstein's relativity theory!

#7105 06/03/06 05:34 PM
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Quote:
Originally posted by manfermef:
Very thanks, i undestand almost all your says, althought i dont understand what this means. "
its potential energy is that of the ground-state of a harmonic oscillator "

Its possible to explain a little bit more to an amateur ?

If you go back to the classical literature on Newton's mechanics, you will realise why the term "inertia" has come into use. This is unfortunately not always explained well in modern books on classical mechanics. It means that a body with mass will resist being moved from rest. This means that the body at rest MUST be in stable equilibrium. Generally in physics most situations where a body is in stable equilibrium, requires a restoring force to come into action when you try to move the body; i.e. the body or particle experiences a potential well; usually parabolic; within which it performs harmonic movement when disturbed. This is why I expect that the wave intensity, which is the solitary electron, will be a three-dimensional zero-point function with energy equal to the rest mass of the electron.

#7106 06/03/06 08:26 PM
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Quote:
Originally posted by manfermef:
Well explained Count!!

Then I sum up that isnt sure the photon is whithout any mass.
At least that its not demonstrate by science.

Its all ok?
That's right, but that there are good theoretical reasons to believe that the photon mass is exactly zero. These theoretical reasons are not fullproof and ultimately you have to rely on experimental results. And experiments can only give you an upper bound on the photon mass.

According to the so-called Standard Model of paticle physics all particles get their mass due to interactions with the Higgs particle. This theory predicts that the photon should be exactly massless, while some other particles like the Z I mentioned are massive. It is possible, however, that new particles like the Higgs exists which do give the photon a tiny mass.

#7107 06/03/06 08:33 PM
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I Thank your efforts to explain something really difficult to understand, Johnny.

Then really the photon cant stop to moving ?

Are you saying that photon cant stop ? when you says that

"A photon can never be at rest within any inertial reference frame."

Then my finally question is: the massless photon dont contradict the Einstein's E=mc2 , because E=mc2 is equal 0 if m=0 ?


mfm
#7108 06/03/06 08:44 PM
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Quote:
Originally posted by Johnny Boy:
I am afraid that Count Iblis II is displaying his ignorance of Galileo's statement of relativity that finally led to Newton's first law. I still think that one should first truly understand Newton's mechanics before spouting nonsense about the physics that came after it. Any "particle" can have two types of energy: kinetic and potential. Without kinetic energy it can only have potential energy. Mass is energy and within the inertial reference frame that a particle with mass is stationary its "rest mass" must represent its lowest energy state. But it is not kinetic energy because the particle is stationary within its proper inertial reference frame. Even Einstein's special theory of relativity tells you that the rest mass is NOT kinetic energy. So it must be potential energy which manifests when the particle is at rest within its inertial reference frame. A photon can never be at rest within any inertial reference frame. So it cannot have potential energy which can be ascribed to mass. What is illogical about this argument Count Iblis II. Or do you not believe that the rest mass is energy? Where do my "personal theories" come in? The argument is based on physics that has been accepted as correct (at low speeds) for more than 300 years, as well as Einstein's special theory of relativity which is now more than 100 years old!!!

Johnny Boy! The question that was asked was whether it is theoretically possible for the photon to have a nonzero mass, given all what we know today (i.e. all the experimentally established facts). By stating that
Quote:
A photon can never be at rest within any inertial reference frame
you are already assuming that the photon is massless. The question is if we can drop this assumption.

If the photon had a tiny mass, you would have to rewrite relativity textbooks because most books talk about the speed of light being an invariant. However, the theory itself would still be the exactly the same. I.e. you would have an invariant maximum speed at which a massless particle would travel instead of ''lightspeed''.

Quote:
Originally posted by Johnny Boy:

Quote:
Originally posted by Count Iblis II:
The Z-boson is a particle that is very similar to the photon. But it is very massive. Special relativity just states that theories must be symmetrical under so-called Lorentz transformation. A massive photon would not violate special relativity at all.
Yes, but in contrast to a photon the Z-boson has a rest mass and can thus be stationary relative to its proper reference frame; or what does the term "rest mass" tels you Count Iblis II? It seems to me that YOU are rather having you own theories; which are at variance with Newton's laws and Einstein's relativity theory!
That's right. But the question was if the photon could in theory have a nonzero rest mass. The answer is that while the best theories we have predict that the photon is exactly massless, it is not theoretically impossible for the photon to have a very very small mass.

#7109 06/03/06 11:55 PM
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theoritically speaking, if a photon is never at rest, it cant have rest mass. one theory that i heard while training in the use of repair of lasers, was that photons are never at rest. they are either moving on their own or they are captured by the electrons of an atom thereby raising the electons energy. the release of that energy results in the photon moving at light speed because it was moving at lightspeed inside the energy shell of the electron.

photons are either particle (with mass) that behave like energy waves or energy waves that act like particle. as yet no one has been able to determine the difference between energy wave and particle enough to describe which it is.


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#7110 06/04/06 12:53 AM
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Topic: Mass of Photon.

I am a neophite here but I can appreciate the ideas that are being considered. My preference is to reduce a concept to its essentials if I can so we can look upon a photon blasting off from the Sun out into space. Either it was not a photon at rest on the Sun or it was created on the spot by the fusion activity of the Sun. When created we can consider that it has no Mass so that is easy. If we contemplate the photon was there to begin with then we must weigh the prospect that the photon was at rest and may possibly have had an original rest status consistent with inherent Mass. When the blast off occurs we either have a conversion of Mass into energy or a uniquely energized particle off into space which may have converted its Mass, if any, into energy.

This new Massless photon will now travel millions of light years expanding constantly to full the ever expanding volumn of space so some stranger far away will see the light.

Question: If the photon has no Mass and if Mass is the source of energy how does the photon manage to travel so many light years away and stiil have substance to be seen by others?

Is the picture the photon carries in its form an indication of substance or of something special?

You know I will be unequiped to challenge any answer you provide.

jjw

#7111 06/04/06 09:42 AM
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Quote:
Originally posted by Count Iblis II:
Quote:
Originally posted by manfermef:
Well explained Count!!

Then I sum up that isnt sure the photon is whithout any mass.
At least that its not demonstrate by science.

Its all ok?
That's right, but that there are good theoretical reasons to believe that the photon mass is exactly zero. These theoretical reasons are not fullproof and ultimately you have to rely on experimental results. And experiments can only give you an upper bound on the photon mass.

According to the so-called Standard Model of paticle physics all particles get their mass due to interactions with the Higgs particle. This theory predicts that the photon should be exactly massless, while some other particles like the Z I mentioned are massive. It is possible, however, that new particles like the Higgs exists which do give the photon a tiny mass.
I am unhappy when people use the sdtandard model as if it has been experimentally verified to be correct. The standard model requires renormalisation and is based on guage symmetries. If it is correct, which I will acept once it is experimentally proved to be correct, then it is still nothing more than an elaborate peeriodic table. Just like Mendeleev's periodic table has been a great breakthrough, it was derived on symmetries without knowing the real physics behind it Bohr finally explained the real physics.

One should note that Count Iblis II bandies around the Higgs boson as if it is an experimental fact: IT IS NOT!. I find his arguments very irresponsible.

The fact is that a particle with mass has a "rest mass" and this logically implies that it can be statiionary relative to its proper inertial reference frame. According to Einstein, a photon can NEVER be stationary. If Einstein is correct than it is impossibnle for a photon to have mass. If it is Einstein's special theory of relativity has to be abandoned.

#7112 06/04/06 09:48 AM
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Quote:
Originally posted by manfermef:
I Thank your efforts to explain something really difficult to understand, Johnny.

Then really the photon cant stop to moving ?

Are you saying that photon cant stop ? when you says that

"A photon can never be at rest within any inertial reference frame."

Then my finally question is: the massless photon dont contradict the Einstein's E=mc2 , because E=mc2 is equal 0 if m=0 ?
E=mc2 does not apply to a photon because a photon do not have potential rest energy; it only has kinetic energy given by Planck's relationship.
If it should be found experimentally that a photon has mass, it would mean that other particles with mass will be able to travel at light speed. It would hange physics completely. Contrary to Count Iblis II I am open to new ideas, but I find it highly unlikely that a photon has any mass.

#7113 06/04/06 10:02 AM
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Quote:
Originally posted by Count Iblis II:
Quote:
Johnny Boy! The question that was asked was whether it is theoretically possible for the photon to have a nonzero mass, given all what we know today (i.e. all the experimentally established facts). By stating that [QUOTE] A photon can never be at rest within any inertial reference frame
you are already assuming that the photon is massless. The question is if we can drop this assumption.

The answer is that while the best theories we have predict that the photon is exactly massless, it is not theoretically impossible for the photon to have a very very small mass.
OK that is another aspect of the question which, I agree, I have not been addressing in my analysis. As I said, I am always open to new ideas; but they are difficult to swallow at this stage of the game when they are based on Higgs bosons; maybe in a couple of years the Hadron Collider will provide an answer. After all, theoretically anything is possible, but it takes experiment to decide which theoretical description really tallies with experiment. You can even have a mathematical description that tallies with experiment because it is mathematically consistent; but it does not really describe the underlying physics; for example, you can repoduce violin music in terms of digital code, but this does not imply that violin nopte are physically digital code. You can assume, like Feynman, that an electron can do "anything" and then add enough of these "anythings" to get a description which seems to represent the electron. This, however, does not prove to me that an electron can do "anything".

#7114 06/04/06 10:12 AM
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Quote:
Originally posted by dehammer:
theoritically speaking, if a photon is never at rest, it cant have rest mass. one theory that i heard while training in the use of repair of lasers, was that photons are never at rest. they are either moving on their own or they are captured by the electrons of an atom thereby raising the electons energy. the release of that energy results in the photon moving at light speed because it was moving at lightspeed inside the energy shell of the electron.
I do not believe that a photon moves at light speed "inside the energy shell of the electron". What happens, in my opinion, is that the photon and "electron orbital" (which I believe is the electron") entangles to form a higher energy electron orbital. For the electron to form a higher-energy staionary electron orbital its mass has to increase; thus the photon energy adds to increase the mass-energy of the bound electron.

Similarly when analysing the photo-electric effect: The photon entangles with the electron wave to in this way increase its mass. If the mass becomes more than the rest mass of the electron; the additional mass acts as kinetic energy which allows the electron to speed away. Thus one do not need to model the photo-electric effect as a collision between two "particles".

Quote:
Originally posted by dehammer:
photons are either particle (with mass) that behave like energy waves or energy waves that act like particle. as yet no one has been able to determine the difference between energy wave and particle enough to describe which it is.
As you see from my alternative analysis of the photo-electric effect, the so-called particle collisions are an illusion; one can explain everything interms of waves that superpose or entangle.

#7115 06/04/06 10:39 AM
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Quote:
Originally posted by jjw004:
Topic: Mass of Photon.

I am a neophite here but I can appreciate the ideas that are being considered. My preference is to reduce a concept to its essentials if I can so we can look upon a photon blasting off from the Sun out into space. Either it was not a photon at rest on the Sun or it was created on the spot by the fusion activity of the Sun. When created we can consider that it has no Mass so that is easy. If we contemplate the photon was there to begin with then we must weigh the prospect that the photon was at rest and may possibly have had an original rest status consistent with inherent Mass. When the blast off occurs we either have a conversion of Mass into energy or a uniquely energized particle off into space which may have converted its Mass, if any, into energy.
Very nice question! Most of the light coming from the sun is "blackbody radiation". Although you can model blackbody radiation as photons following Bose-Einstein statistics; it can also be modelled as standing waves following Maxwell-Boltzmann statistics. I believe the latter is the correct picture before a photon is ejected from the sun on its journey. Why? Because the energy-level density of black-body radiation can only be derived from the boundary conditions applicable to standing waves. Photons as localised entities cannot be used to calculate the energy-level density. Thus one has to conclude that the waves are "stationary" waves; however, these waves are not "time-independent", like a stationary wave representing a particle with mass. They are rather similar to standing waves on a violin string. The standing wave is formed because you have two waves moving in opposite directions (each with speed c) because you get reflection at the boundaries. This means that an escaping light wave, most probably, "collapses" to form a more localised entity when it leaves the sun. At that stage this entity need not be completely localised to be what we call a photon; it only needs to "collapse" into the latter state when it is observed by a detector like your eye.

Quote:
Originally posted by jjw004:
Topic: Mass of Photon.
Question: If the photon has no Mass and if Mass is the source of energy how does the photon manage to travel so many light years away and stiil have substance to be seen by others?
Light has energy. As agreed above, even by Count Iblis II, mass means that a "particle" can be stationary relative to an inertial reference frame. As far as we know, this is not possible for light. This does not imply that light has no energy; it must have kinetic energy because it is always moving with a speed c

Quote:
Originally posted by jjw004:
Topic: Mass of Photon.
Is the picture the photon carries in its form an indication of substance or of something special?
jjw
I do not understand what you are trying to ask here?

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Quote:
Originally posted by Johnny Boy:
[QUOTE]I do not believe that a photon moves at light speed "inside the energy shell of the electron". What happens, in my opinion, is that the photon and "electron orbital" (which I believe is the electron") entangles to form a higher energy electron orbital. For the electron to form a higher-energy staionary electron orbital its mass has to increase; thus the photon energy adds to increase the mass-energy of the bound electron.

Similarly when analysing the photo-electric effect: The photon entangles with the electron wave to in this way increase its mass. If the mass becomes more than the rest mass of the electron; the additional mass acts as kinetic energy which allows the electron to speed away. Thus one do not need to model the photo-electric effect as a collision between two "particles".

As you see from my alternative analysis of the photo-electric effect, the so-called particle collisions are an illusion; one can explain everything interms of waves that superpose or entangle.
that is one theory, not totally new, but different that any ive seen. still neither this or the one i mentioned has ever been proven. nor has any of the other theories as to exactly what a photon is. One day, someone will come up with conclusive proof, and the arguement will end. at that point we (or our decendants) will know if it has mass or not. until then no one will know exactly. that is why i alway add that line about it being one or the other (watch it be neither) when ever i discuss laser or light.


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#7117 06/04/06 02:52 PM
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Quote:
Originally posted by Johnny Boy:
Quote:
Originally posted by Count Iblis II:
Quote:
Originally posted by manfermef:
Well explained Count!!

Then I sum up that isnt sure the photon is whithout any mass.
At least that its not demonstrate by science.

Its all ok?
That's right, but that there are good theoretical reasons to believe that the photon mass is exactly zero. These theoretical reasons are not fullproof and ultimately you have to rely on experimental results. And experiments can only give you an upper bound on the photon mass.

According to the so-called Standard Model of paticle physics all particles get their mass due to interactions with the Higgs particle. This theory predicts that the photon should be exactly massless, while some other particles like the Z I mentioned are massive. It is possible, however, that new particles like the Higgs exists which do give the photon a tiny mass.
I am unhappy when people use the sdtandard model as if it has been experimentally verified to be correct. The standard model requires renormalisation and is based on guage symmetries. If it is correct, which I will acept once it is experimentally proved to be correct, then it is still nothing more than an elaborate peeriodic table. Just like Mendeleev's periodic table has been a great breakthrough, it was derived on symmetries without knowing the real physics behind it Bohr finally explained the real physics.

One should note that Count Iblis II bandies around the Higgs boson as if it is an experimental fact: IT IS NOT!. I find his arguments very irresponsible.

The fact is that a particle with mass has a "rest mass" and this logically implies that it can be statiionary relative to its proper inertial reference frame. According to Einstein, a photon can NEVER be stationary. If Einstein is correct than it is impossibnle for a photon to have mass. If it is Einstein's special theory of relativity has to be abandoned.
I agree that the Standard Model is just a model and that the Higgs hasn't been experimentally confirmed to exist. But you do have to acknowledge that the W and the Z particles and the various relations between their masses were correctly predicted. That's a very strong result.

I think I will start another thread on renormalization some time in the future here. renormalization can be seen as a trick to remove infinities. However, as pointed out by Wilson, it is more natural to consider field theories as an effective theory valid at low energies obtained by integrating out the high energy degrees of freedom.

So, you assume that the unknown ''theory of everything'' reduces to the standard model at low energies, just like magnetism in a solid can be described by a renormalizable phi^(4) field theory.

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Quote:
Originally posted by Johnny Boy:
Quote:
Originally posted by Count Iblis II:
Quote:
Johnny Boy! The question that was asked was whether it is theoretically possible for the photon to have a nonzero mass, given all what we know today (i.e. all the experimentally established facts). By stating that [QUOTE] A photon can never be at rest within any inertial reference frame
you are already assuming that the photon is massless. The question is if we can drop this assumption.

The answer is that while the best theories we have predict that the photon is exactly massless, it is not theoretically impossible for the photon to have a very very small mass.
OK that is another aspect of the question which, I agree, I have not been addressing in my analysis. As I said, I am always open to new ideas; but they are difficult to swallow at this stage of the game when they are based on Higgs bosons; maybe in a couple of years the Hadron Collider will provide an answer. After all, theoretically anything is possible, but it takes experiment to decide which theoretical description really tallies with experiment. You can even have a mathematical description that tallies with experiment because it is mathematically consistent; but it does not really describe the underlying physics; for example, you can repoduce violin music in terms of digital code, but this does not imply that violin nopte are physically digital code. You can assume, like Feynman, that an electron can do "anything" and then add enough of these "anythings" to get a description which seems to represent the electron. This, however, does not prove to me that an electron can do "anything".
I agree with this, but this argument can work in many ways. E.g. when we detect particles like electrons or photons what we really 'see'' are effects in macroscopic detectors. The theory describing electrons and photons, Quantum Mechanics, in fact precludes you from observing particles in the same way you can observe classical objects. This means that it is theoretically possible that the Standard Model is just some effective theory and that the particles it describes don't really exist.

Such theories have been proposed by 't Hooft. He has proposed deterministic models. Bell's theorem is evaded because the particles are only effective mathematical objects that appear in intermediary calculations.

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Quote:
Originally posted by Count Iblis II:
I agree that the Standard Model is just a model and that the Higgs hasn't been experimentally confirmed to exist. But you do have to acknowledge that the W and the Z particles and the various relations between their masses were correctly predicted. That's a very strong result.

I think I will start another thread on renormalization some time in the future here. renormalization can be seen as a trick to remove infinities. However, as pointed out by Wilson, it is more natural to consider field theories as an effective theory valid at low energies obtained by integrating out the high energy degrees of freedom.

So, you assume that the unknown ''theory of everything'' reduces to the standard model at low energies, just like magnetism in a solid can be described by a renormalizable phi^(4) field theory. [/QB]
Wilson's argument is still just a conjecture. Nonetheless,t we are moving nearer to an understanding. As I have acknowledged, the physics that has been done using quantum field theory should not be thrown out of the window. Just as Bohr's atom did not invalidate the applicability of the Periodic Table of the Elements. There has been extraordinary successes like the W and Z particles; however, I do not believe that these theories are complete theories and their complexity is, to my mind, also an indication that there must be simpler mechanisms behind the symmetries predicted and observed. I believe that the real physics involved might be simpler than we anticipate at present. Sometimes I think that we are trying to fix what do not need fixing; and in the process we are developing wonderful new mathematics but less and less of an understanding of the physics involved.

In turn you do have to acknowledge that on another thread I have shown aspects of superconduction which the BCS model cannot explain; and I have postulated a single mechanism that explains superconduction in all the superconductors that have been discovered to date. Whatever you might think of me subjectively; do you not think that under such circumstances the "experts on superconduction" should evaluate the new model objectively vis-avis the BCS model; instead of just running away in horror while slinging around insults? Is this what scientists have become? Or have they always been the real dogmatists?

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I dont agree so easilyi with Johnny argument:

"E=mc2 does not apply to a photon because a photon do not have potential rest energy; it only has kinetic energy given by Planck's relationship"

I think that E=mc2 implies or predicts that no one
particle in the Nature could be massless. Because his energy would be 0, and how to move in with E=0. Isn't impossible?


mfm
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Quote:
Originally posted by Count Iblis II:
[QUOTE]I agree with this, but this argument can work in many ways. E.g. when we detect particles like electrons or photons what we really 'see'' are effects in macroscopic detectors. The theory describing electrons and photons, Quantum Mechanics, in fact precludes you from observing particles in the same way you can observe classical objects. This means that it is theoretically possible that the Standard Model is just some effective theory and that the particles it describes don't really exist.

Such theories have been proposed by 't Hooft. He has proposed deterministic models. Bell's theorem is evaded because the particles are only effective mathematical objects that appear in intermediary calculations.
Yes this is a core argument and I believe very central to making progress in future physics. It is based on the acceptance that the Copenhagen interpretation is correct. I think it is this interpretation that has been leading us around in circles. It is the Copenhagen interpretation that precludes you from observing quantum mechanical "particles" in the same way you can observe classical objects; however, it does not explain why we can observe an electron (which is a quantum "particle") to follow a classical path except by invoking "magic". To say it is because the measurement apparatus is "classical" only avoids the dilemma. You have to bring in the "magic wand" by saying that sometimes you can see them and sometimes you cannot. If you rather accept that everything consists of waves and when we "observe" particles we observe localised waves, and when we do not, the waves are near to each other to superpose or entangle, then I believe that I can re-iterpret Quantum Mechanics without invoking wave-particle duality "magic". You then find that all interactions (even the photo-electric effect) are typically what you expect when waves interact.

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Quote:
Originally posted by manfermef:
I dont agree so easilyi with Johnny argument:

"E=mc2 does not apply to a photon because a photon do not have potential rest energy; it only has kinetic energy given by Planck's relationship"

I think that E=mc2 implies or predicts that no one
particle in the Nature could be massless. Because his energy would be 0, and how to move in with E=0. Isn't impossible?
This is the nice thing in life; or rather should be the nice thing in life: We can agree to disagree and argue about it, hopefully politely. I have difficulty to follow why E=mc2 must mean that every particle has mass.

If you write down the energy equation derived by Einstein you will find that a photon must have zero mass in order to have the momentum E/c which, within experimental accuracy,it has. experimentally has.

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A photon is usually thought of as a massless particle. However we can associate a mass with a photon by using two well known relations. The first is Einstein's theorem on the equivalence of energy and inertia that is usually expressed as E = m c^2. The second, also due to Einstein, is the energy-frequency relation. This is usually written as E= h f, where h is Planck's constant and f is the frequency of the light. By combining these we get m = h f /c^2. This is the mass equivalent to the energy of the photon.

A photon has no rest mass, as such. It does have energy and energy is equivalent to mass. So light posesses inertia or, one might say, inertial mass. This may sound odd but it is demonstrated by the Compton Effect. In this experiment a photon interacts with an electron in a way taht is like a macroscopic particle collision. In other words the photon acts like a particle just as the electron does.

Dr. R.

P.S.: Another form of the energy relation is used in particle physics is

E^2 = (m0 c^2)^2 + (pc)^2.

In this m0 is the rest mass of the particle in question. Suppose that m0 = 0, as with a photon, then we have

E = pc = (m v)c.

Since we are looking at a photon v = c so that this equation becomes

E = mc^2.

In this expression m is not the proper (rest) mass.

We can also say that

E / c = p = h / L = h f / c.

Rearranging this gives the Einstein frequency relation E = h f. By the way Einstein got this relation from his analysis of the photoelectric effect.

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Very well explained dr_rocket. What I have been talking about are particles which have rest masses. All present theories are in accord that a photon cannot have a rest mass.

The omly point a disagree on is to say categorically that the photon act as a particle just like an electron: it only seems as if they act like particles when they "collide". I do not believe that they are REALLY particles.

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Still not ok , Johnn.
It seemes to me you established that

"A photon has no rest mass" due to
m= hf/c^2.


But why that m=hf/c^2 isnt a rest mass?
Isn't absurdity that photon hasn't mass?
Why do you talk about photon as a particle if photon hasnt mass ?
Whats the source of his energy?


mfm
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Quote:
Originally posted by manfermef:
Still not ok , Johnn.
It seemes to me you established that

"A photon has no rest mass" due to
m= hf/c^2.


But why that m=hf/c^2 isnt a rest mass?
Isn't absurdity that photon hasn't mass?
Why do you talk about photon as a particle if photon hasnt mass ?
Whats the source of his energy?
I do not say that a photon is a "real particle"; I believe that "particles" do not exist. A photon is a light wave that has collapsed to inhabit a small region of space. This happens when the light is being absorbed by an electron; which is also not a "particle". The absorption is akin to a coalescence of the two waves (entanglement). From Galileo's relativity to Newton's laws, "rest mass" relates to the ability of a "body" to be "at rest" within a uniformly moving inertial reference frame. According to Einstein light can never be stationary relative to an inertial reference frame; it musy always move with a speed c. One can, however, assign mass to the kinetic energy that a "body" with rest mass has so the kinetic energy can be written as T=mc^2-m(rest)c^2. where m is larger than m(rest). Similarly, for a light wave (photon?), except that for "a photon" you have that m(rest)=0. I hope this helps.

O yes a lst comment: I believe that in the case of light AND matter the energy relates completely to wave energy. The only difference is that matter can be descibed (by the Schroedinger equation) in terms of stationary time-independent waves; i.e. the wave can be stationary relative to an inertial reference frame; while light cannot be described by stationary time-independent waves (as can be verfified when solving Maxwell's equations).

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Thank you JB:

Possibly the last part of my question assumes something that does not exist. The part you did not understand was due to my failure to be more precise in forming the question. I try again.

When our astronomers look into the Galaxy they see pictures that were transported here by light and it is that light which is either the photon itself or the photon is the carrier of that light.

If so the photon has an image that was created not only at the time it left the surface of that foreign star but of what ever else it picked up as it left that distant Galaxy on its way to us. If the photon is pure energy where is this picture stored so it can get here to us to wonder at?

jjw

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the photon is the image, what you see is the sum of the photons striking the retinas at the same time from objects around you. they dont 'carry' the image. if there were one photon, all you would see is a short burst of light, with the only info being the frequency of that photon. a group of photons coming from a large area traveling many light years will be spread out and only a few of them will reach you. when they do, they tell you the frequency of all of those that came from that part of the galazy. since the frequency is dependant on how much energy was released in those photons and the energy of the star will be fairly constant, you will see a constant color.


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#7129 06/04/06 07:52 PM
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Quote:
Originally posted by jjw004:
Thank you JB:

Possibly the last part of my question assumes something that does not exist. The part you did not understand was due to my failure to be more precise in forming the question. I try again.

When our astronomers look into the Galaxy they see pictures that were transported here by light and it is that light which is either the photon itself or the photon is the carrier of that light.

If so the photon has an image that was created not only at the time it left the surface of that foreign star but of what ever else it picked up as it left that distant Galaxy on its way to us. If the photon is pure energy where is this picture stored so it can get here to us to wonder at?

jjw
What left the star is probably not a "photon" as it is currently interpreted by the scientific community; i.e. a localised "particle". I believe that it only becomes a localised "photon" once it inertaacts with matter; e.g. our eyes or any other detector. If, on the way, the wave encountered another detector, it would have been absorbed and re-emitted. We will then observe it as a "scatterred photon". While absorbed by the detector, the energy is stored "in the absorber". Afterwards it is released as a (scatterred) wave which collapses into a "photon" when we it reaches our eyes.

#7130 06/04/06 08:22 PM
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Thanks again:

It is a more serious question than I can frame.
Consider the surface of a light source 10,000 light years away from us. Calculate the size of the photon that left that surface and compare it to the size it must achieve at the end of the journey. If the photon expaned constantly over that great distance it would be thousands of times larger that when it started out. If it did not expand then it must be dividing itself to continue to fill up the ever increasing volumn so that no empty space would be left inbetween.

This does not require an answer by any one. It is just one of my curiosities of which I have many to play with. Existing scientific thinking is not always satisfying for me.
jjw

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jjw004,
'One photon does not an image make...`
The only 'size` that has much meaning in
relation to a photon is it's wave-length.
It might help you to consider a photon as
as energetic event, frozen in time, fleeing
through the universe at 'C`,
seeking an opportunity to undo the itself,
(the event).
Felt poetic today, but the above is surprisingly
accurate come to think of it.
Pragmatist

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Quote:
Originally posted by jjw004:
Thanks again:

It is a more serious question than I can frame.
Consider the surface of a light source 10,000 light years away from us. Calculate the size of the photon that left that surface and compare it to the size it must achieve at the end of the journey. If the photon expaned constantly over that great distance it would be thousands of times larger that when it started out. If it did not expand then it must be dividing itself to continue to fill up the ever increasing volumn so that no empty space would be left inbetween.

This does not require an answer by any one. It is just one of my curiosities of which I have many to play with. Existing scientific thinking is not always satisfying for me.
jjw
the size of the photon is the same as it is when it leave the surface of the sun. the thing is the number of them per square centmeter at the surface or the sphere 100000 light years away is extreamly small. the entire surface of the sun is sending out photons in all directions. some of them will be assorbed by things in the way, some will be deflected, and other will be reflected. when you look at the star, what you are seeing is the sum total of the all the photons thrown off the surface in your direction (or more spacifically, the directions of your eyes) that was not absorb, deflected, or reflected along the way that arrive at that instant.


the more man learns, the more he realises, he really does not know anything.
#7133 06/05/06 12:04 AM
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jjw, why on earth is the size of the photon so important? Don't you think that you are forcing a perspective/interpretation on something that "we" are aware at this time that we cannot have a good pictural image of?

How does this help anything?

#7134 06/05/06 10:18 AM
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Welcome back Pasti. I hope all went well with your endeavours during April-May.

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Hi Pasti:

Very nice to hear from you, even with impatience.

I suppose the size of the photon or the "wave" which forms the photon is of no importance to any one that knows it all about photon's.

It just seems to me that something is happening that may be important for us to understand and I broach the subject with a simplistic approach. No one need trouble themselves with what they see as a useless question- but- suppose that 1 degree of a distant stars surface is 30,000 miles. That 1 degree of surface emiting photon's will strech into many millions of miles after traveling many thousands of light years to get to me. The volumn has increased accordingly so photon's that left that star are spread out now.
I am aware that the answers provided are well founded but I remain puzzeled and that is my problem and not the members problem. I think just possibly that the size of the photon may be the reason for a limit on the speed of light.

I may try to restrain myself better. Thanks.
jjw

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Thanks for the warm welcomming. And as an added bonus, I still have all my ranking stars. Silence is golden, as usual...

Sorry for the brevity, but I am still swimming in it thick until the end of this month. Anyway, folks, feel free to email me to take it where we left it, and I will get to it sooner or later.

jjw, the issue that is puzzling you has nothing to do with the size of the photon, neither as what we commonly percive as size, nor with the wavelength.

The answer to your question is simply kmown as the intensity law. The intensity of light (i.e. the number of photons per unit time) incident on a transversal surface varies with the inverse squared distance to th4e surface (neglecting scattering and absorption).I~I0/r^2, where I0 is the intensity of the source. Replace intensity with the photon rate, and you got your answer.

If you want to see where this law comes from, there is a nice way to do it. Take a piece of paper, and in its center draw a small blob. that is your source. Take a protractor, and now from your blob draw outwardly every say, 5 degrees, straight lines. Those are your photons emitted by the source. Now, using the blob as the center, take a compass (geometrical copmpass and not a navigational one) and draw concentric circles with radii 1 cm, 2cm, 3cm, 4cm, etc. If you use a letter sized paper, you should get quite a few such concentric circles.

Here is where your imagination must come into place. Imagine these circles as the intersection of concentric spheres with the plane of your paper, and now you have a source of light illuminating the space.

Take now your 1cm radius circle, and chose an arbitrary semicircle out of it. Count how many lines go through this semicircle. If you drew the lines every 5 degrees, you will have 36 lines going through this semicircle.

Now, the length of the semicircle is pi*1cm=3.14 cm. On each of the remaining concentric circles (of increasing radius) measure a length along the circumference equal to 3.14cm, and count how many lines go through this length for each of the circles. Plot the number of lines through this portion of the circumference as a function of the radius, and as a function of the inverse squared radius. Let me know what you get.

Hope this helps.
Cheers.

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Quote:
Originally posted by jjw004:
No one need trouble themselves with what they see as a useless question
we will not trouble ourself with a useless question... when we find it. thats kind of hard to do. this one certainly is not useless.


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Thank you; Pasti.

I never noticed before that you were member number 5!

Your example is very good and that is the sort of mind game I play when dealing with things I think are as yet worth further consideration. You know something of my simplistic manners so I will try what some of my betters referred to as a mental experiment. I will try to be brief.

My first conjecture is that the statement ?nothing can exceed the speed of light in a true vacuum,? implies that unhindered light has a fixed speed.
The next conjecture is why would light be limited in its speed unless the vacuum was a cause or the substance of light itself, the photon, was the cause. We know that a vacuum is not without hindrance because there are invisible gravitation concerns and electromagnetic factors but for this mental experiment we must conceive a totally benign vacuum that provides no impediment against light to reach its maximum potential.

All we have left at this point is the light consisting contribution by the source and the means by which it gets from here to there. To my simple way this means that a light source, photon/wave/particle or whatever is not the controlling factor because science tells us all photons travel within the same speed limit, in general, without regard to the size or the energy of the source. IF there is a universal limit on the speed of light, and I know of no proven explanation for same, then that fact should be found within the makeup of light/photons themselves.

I suspect that your use of intensity equates to my use of density. We know that not all sources of light will carry on as far as the most ?intense? or to me, the densest. The last conjecture is that light blasted off from a powerful source should gain speed constantly as it escapes the gravitational restraints close the source. Why would anything in our unique vacuum stop it or slow it down? If we have pure energy on the loose some thing must be draining some of that energy away to keep the photon from going faster.

So, I say it is the expansion of the photon as it travels from there to here with the demands of the extra energy being devoted to filling up ever increasing volumes of space providing a limit on the speed. That is why I am interested in the natural expansion of light photons.
Probably not very scientific but at least verbose.

jjw

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Note, based on my view light condensed into a stream without permiting expansion should have no limit to its speed. Lasers get close but not enough of a squeese.

jjw

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I am afraid that Count Iblis II is displaying his ignorance of Galileo's statement of relativity that finally led to Newton's first law. I still think that one should first truly understand Newton's mechanics before spouting nonsense about the physics that came after it. Any "particle" can have two types of energy: kinetic and potential. Without kinetic energy it can only have potential energy. Mass is energy and within the inertial reference frame that a particle with mass is stationary its "rest mass" must represent its lowest energy state. But it is not kinetic energy because the particle is stationary within its proper inertial reference frame. Even Einstein's special theory of relativity tells you that the rest mass is NOT kinetic energy. So it must be potential energy which manifests when the particle is at rest within its inertial reference frame. A photon can never be at rest within any inertial reference frame. So it cannot have potential energy which can be ascribed to mass. What is illogical about this argument Count Iblis II. Or do you not believe that the rest mass is energy? Where do my "personal theories" come in? The argument is based on physics that has been accepted as correct (at low speeds) for more than 300 years, as well as Einstein's special theory of relativity which is now more than 100 years old!!!
How about I take a perfect box filled of a perfect reflective material, and shoot into it a beam of light. I then close the box. The box doesn't move , and thus the system is stationary with concern to momentum. Will the box not gain a very small amount of mass?

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Quote:
Originally posted by MBroderick:
[QUOTE]How about I take a perfect box filled of a perfect reflective material, and shoot into it a beam of light. I then close the box. The box doesn't move , and thus the system is stationary with concern to momentum. Will the box not gain a very small amount of mass?
Good question!

I believe that the answer to your question could be as follows: The light will be reflected between the walls to form standing waves; each standing wave is formed by two wave components moving with speed c (relative to the box) into opposite directions. The light waves thus still have kinetic energy which can be equated to mass. This will cause the weight of the box to increase. It thus seems as if the light under these conditions has a rest mass which adds to the total mass; however, light on its own do not have rest mass. It seems that in order for light energy to add to the mass of another material (like the box), the light has to be confined (as it is within the box). I believe that this is also what happens when light (a "photon") is absorbed by an atomic "electron". The incoming light-wave coalesces (entangles) with the electron-wave (orbital), becomes confined, and thus adds to the mass. The electron orbital then has to "morph" into a higher enery orbital; i.e. one with more mass.

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Quote:
Originally posted by MBroderick:
How about I take a perfect box filled of a perfect reflective material, and shoot into it a beam of light. I then close the box. The box doesn't move , and thus the system is stationary with concern to momentum. Will the box not gain a very small amount of mass?
there is already something close to this. its called a black hole device. basically its a cylinder that is as close to perfectly reflective inside. a beam of light enters though a small hole near in such a way that it bounces around the cylinder always going in a circle. since it cant get a angle to hit the hole without hiting a mirror that would bounce it back in, it has to keep going. unfortuantly i dont know alot of the test that were done with it.


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jjw, I will post the reply to your post later, I am working on it.

dehammer:"there is already something close to this. its called a black hole device. basically its a cylinder that is as close to perfectly reflective inside."

dehammer, let's keep the terminology correct. The device you mention is not a black-hole device it is caled a black-body radiation device. The difference between this device and a black-hole cannot be emphasized enough.

In my time, the device was not a cylinder, but a sphere (for the obvious reasons), and it was called the Ulbricht sphere. It was used to determine the thermal distribution of the spectral density of the radiation emitted by an optical black-body,you know,the ~T^4 dependence of the spectral density, and similar.

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Quote:
Originally posted by Johnny Boy:
Quote:
Originally posted by MBroderick:
[QUOTE]How about I take a perfect box filled of a perfect reflective material, and shoot into it a beam of light. I then close the box. The box doesn't move , and thus the system is stationary with concern to momentum. Will the box not gain a very small amount of mass?
Good question!

I believe that the answer to your question could be as follows: The light will be reflected between the walls to form standing waves; each standing wave is formed by two wave components moving with speed c (relative to the box) into opposite directions. The light waves thus still have kinetic energy which can be equated to mass. This will cause the weight of the box to increase. It thus seems as if the light under these conditions has a rest mass which adds to the total mass; however, light on its own do not have rest mass. It seems that in order for light energy to add to the mass of another material (like the box), the light has to be confined (as it is within the box). I believe that this is also what happens when light (a "photon") is absorbed by an atomic "electron". The incoming light-wave coalesces (entangles) with the electron-wave (orbital), becomes confined, and thus adds to the mass. The electron orbital then has to "morph" into a higher enery orbital; i.e. one with more mass.
This makes much more sense, and I know understand where you were coming from in your earlier posts. Confinement of the wave is possible due to its size, but would you say that this confinement is an entaglement of two waves, or a change of phase, or something altogether unrelated to the typical ideas of wave interaction?

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Quote:
Originally posted by Pasti:
dehammer, let's keep the terminology correct. The device you mention is not a black-hole device it is caled a black-body radiation device. The difference between this device and a black-hole cannot be emphasized enough.

In my time, the device was not a cylinder, but a sphere (for the obvious reasons), and it was called the Ulbricht sphere. It was used to determine the thermal distribution of the spectral density of the radiation emitted by an optical black-body,you know,the ~T^4 dependence of the spectral density, and similar.
Ive heard it referred to as a black hole device, as it allowed light to enter but not escape. the sphere did as the light would refract a little in all directions and would eventually bounce. back out. the cylander did not allow that, as if the light went in to a direction no alined with the hole, it would hit a wall and then hit the cylander again.

perhaps that was not its official name.


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Hi all,

Been a bit busy the last few days - lost track of this thread. On looking it over a few things occur to me.

MBroderick brought up the idea of a container with perfectly reflection walls. This idea was original thought of by Adolfo Bartoli in 1876. He was arguing, from Maxwell's relatively new theory of electromagnetism, that light should exert a pressure. He imagined light trapped in a cylinder, with a piston at one end, all with perfectly reflecting walls. He used the second law of thermodynamics to deduce that the trapped light would and in fact must make a pressure. This pressure is not very big and it was not until about 1905 when Nichols and Hull and independently by Lebedev actually measured it.

The Bartoli Cylinder was again used by Boltzmann to derive Stefan's radiation law. This is the law that Pasti is quoting. It says that the total radiated power of a body at temperature T is gigen by the Stefan-Boltzmann law

P = sigma T^4

where P is power, sigma is called - what else - the Stefan-Boltzman constant and T is the absolute temperature.

The Bartoli cylinder was transformed into a sphere by Wilhelm Wien. He was studying the adiabatic compression of radiation with an eye toward finding a good radiation law. He was using a mostly thermodynamic arguement.

Now all these ideas were mere thought experiments. Richard Ulbricht (1849-1923) actually made what is called a spherical integrator that is a rigid version of a Wien sphere. This is normally used as a kind of radiation calorimeter or to provide a homogeneous isotropic light for test purposes.

By the way light does have inertia. In fact this is equivalent to E = mc^2. To see the derivation look at Max Born's book entitled "Atomic Physics". It is a Dover book so so it is easy to get. I would quote it here - because the derivation is easy and visilizable - but I have to runn off right at this moment.

Dr. R.

P.S. Made some small mods here.

#7147 06/08/06 09:03 AM
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Quote:
Originally posted by MBroderick:
[QUOTE]This makes much more sense, and I know understand where you were coming from in your earlier posts. Confinement of the wave is possible due to its size, but would you say that this confinement is an entaglement of two waves, or a change of phase, or something altogether unrelated to the typical ideas of wave interaction?
I have come to the conclusion that waves can superpose to occupy the same region in space in two different ways: (i) normal superposition where the waves retain their identities and move through each other thus generating an interference pattern. I have termed this "enmeshment" of waves. The standing waves in the box you have proposed are enmeshed; i.e. they move through eacch other and generate a standing wave interference pattern. (ii) the second mechanism is what I will call "entanglement": in this case the two waves coalesce and totally lose their separate identies in order to form a wave with a new "single" identity; for example when two electrons form a covalent bond. I have extended this concept to the absorption of EM radiation by an atomic electron. The light wave entangles with the ground state orbital, thus increasing its mass energy to, in this way, force it to "morph" into a higher energy electron orbital. The result in this case is not just a superposition of the two waves, but the formation of a single (holistic) electron orbital with a higher energy. The original two wave identities disappear completely.

In the case of the box one can probably argue that the light also entangles with the box in order to generate another box with a higher energy. Nonetheless, inside the box the light waves do not entangle with each other, but enmesh to form standing waves. A thought just struck me: can one not copnsider the ground state electron orbital as a "box" within which the absorbed light forms standing waves after the orbital has morphed into a higher energy orbital?

Another aspect of differentiating between "enmeshment" and "entanglement" is a new possible explanation for the EPR experiment. When two electrons entangle, they form a single holistic wave eintity with spin zero. When a spin measurement is subsequently made, the wave has to decompose into two entities, each being an electron wave: this has to occur so that the spins are opposite; however, after disentanglement the holistic wave with spin zero does not exist anymore, so that the two electrons cannot communicate with each other faster than light speed anymore. So I believe Einstein was correct: two "particles" cannot communicate faster than light speed; but a single holistic wave can be in immediate contact with itself over the whole region of space that it occupies.

#7148 06/12/06 11:17 PM
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On June 6 I made a reply to Pasti and I want to follow up on that poinr here. My view is simply a conjecture on my part arrived at a long time ago but voiced only recently. I search the Web a little to see what some others may have said about a cause for a limit on the speed of light and I was surpized at complex it can get.

http://users.bestweb.net/~jond4u/slolight.htm

This gentlemen covers the Universe when he might have said simply that the expansion of the photon filling up volumns of space may account for the limit on the sped of light. That does not mean either one of us are correct but it is interesting to me to see different approaches.
jjw

#7149 06/15/06 01:51 PM
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Frankly Sir I do not wish to elaborate right now but to me it appears that there is no limit on max Speed...and information can be carried at any speed but nature and form of the information spread changes.

#7150 06/15/06 07:46 PM
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Frankly to you dkv!

Did you mean speed instead of "spread".

Any way we, right now, do not know if some distant Galaxy is sending light to us that is traveling on its way faster than the speed of light we measure in this locale. We do know that Einstein and about all academics contend that there is a limit to the speed of light and use the measure we make here as a likely limit.

You appear to be talking about something else as if the "information form" or their "nature" is a factor and you lost me there. Any way it is nice to hear from you again.
jjw

#7151 06/15/06 09:14 PM
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Quote:
Originally posted by dkv:
Frankly Sir I do not wish to elaborate right now but to me it appears that there is no limit on max Speed...and information can be carried at any speed but nature and form of the information spread changes.
dkv, can you back this statement up with some research results? I'm sure many people would like to know how to go faster than light speed.

#7152 06/16/06 06:36 AM
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No Sir.

Let us understand the nature of Information itself...
Please note every information can not be transmitted...
Let me give you an example...
We know that we humans are composed of Conscious and Unconscious thoughts....
Concious thoughts read what is being read ....
Unconscious thought reads what is not being read..
When visit a beautiful place we see large mountains ,flowers , good air , rivers ..etc and we say it feels good ...
somehow we feel beyond our conscious mind can observe...
Similary the same feeling comes when we a vast sea.. or look at the vast sky... or see a village wihout any obstructions...
Similarly as you read what I write .. you read more than what I read.. it is very personal..
This information came to you even before I posted anything...
Thats how speed barrier gets broken.
Now let me ask you the same question I asked in Evolution of Physics Debate..
Does the Information depends on the number of Observers Invovled...?
Greater the number observers greater is the instability of truth..
This is my principle of Uncertainity of Consciousness...
Now please do not delete it...
Trust me .. it wont hurt..
Thank you so much.

#7153 06/16/06 03:57 PM
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Thank you dvk for this wonderful treatise on the value of psychotherapy.

Please seek support from a competent psychiatrist.


DA Morgan
#7154 06/20/06 02:18 AM
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Quote:
Originally posted by dkv:
No Sir.

Let us understand the nature of Information itself...
Please note every information can not be transmitted...
Let me give you an example...
We know that we humans are composed of Conscious and Unconscious thoughts....
Concious thoughts read what is being read ....
Unconscious thought reads what is not being read..
When visit a beautiful place we see large mountains ,flowers , good air , rivers ..etc and we say it feels good ...
somehow we feel beyond our conscious mind can observe...
Similary the same feeling comes when we a vast sea.. or look at the vast sky... or see a village wihout any obstructions...
Similarly as you read what I write .. you read more than what I read.. it is very personal..
This information came to you even before I posted anything...
Thats how speed barrier gets broken.
Now let me ask you the same question I asked in Evolution of Physics Debate..
Does the Information depends on the number of Observers Invovled...?
Greater the number observers greater is the instability of truth..
This is my principle of Uncertainity of Consciousness...
Now please do not delete it...
Trust me .. it wont hurt..
Thank you so much.
One more time, please stick to Science and Science related topics. Your attempts to derail this discussion have been noted. If you persist in posting this sort of metaphysical crap I will start deleting your posts. You have been warned.

Amaranth
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#7155 07/13/06 03:56 AM
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Mass of the photon as predicted by QED is zero.
Current experimental measurements on the mass of the photon put an upper limit to 6*10^-17 eV.
Only massless particles can travel at c.
No massive particle (m>0) can travel at c.
Hope that this settles it.

#7156 07/13/06 03:59 AM
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The correct relationship is:

E^2=(mc^2)^2+(pc)^2

For photon m=0, therefore E=pc.

Do not use E=mc^2, it is an incomplete relationship.

#7157 07/13/06 05:49 AM
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How many times I have written that equation here. I've lost count.

Anticipate disappointment.


DA Morgan
#7158 07/13/06 06:17 AM
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Quote:
Originally posted by DA Morgan:
How many times I have written that equation here. I've lost count.

Anticipate disappointment.
So what? We need to be perseverent and consistent in the message. Eventually it will take. wink

#7159 07/13/06 04:48 PM
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You must be younger than me. ;-) Much younger!

I grow weary of wanton and wilfull ignorance.

But you are correct ... we must persevere.


DA Morgan
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