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  #31 (permalink)  
Old 10-May-2005, 07:49 PM
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Quote:
Originally Posted by Tensor
Quote:
Originally Posted by akirabakabaka

lyndonashmore never claimed that Compton has anything to do with this interaction. He has specifically argued against it. Normandy6644 claims that Comtpon effect is involved in free-electron collisions. This seems wrong.
Quite right aki. My appologies Lyndon. I guess I'll also go back and reread the thread.
Yeah sorry, I didn't mean it to say that free electrons in the IG plasma experience the Compton effect, only that free electrons cannot absorb or emit photons.
  #32 (permalink)  
Old 10-May-2005, 08:43 PM
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Quote:
Originally Posted by lyndonashmore
But they are the same effect Papageno, only in glass the electrons don't recoil because they are fixed in a crystal lattice. In the plasma of space the electrons recoil on absorption and re-emission so energy is lost to the electron. Photon loses energy, frequency reduces wavelength increases. It is redshifted. easy.
I wouldn't in my wildest dreams call myself a physicist, but I have a question. How does the photon loose energy to the plasma? I think I understand how your rebounding mechanism works, but I don't understand how the energy is lost, or where it goes. Considering the photon output of your average galaxy, I would have thought that the amount of energy being dumped into this IG plasma would be enormous!
  #33 (permalink)  
Old 10-May-2005, 08:51 PM
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Originally Posted by TheAtomium
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Originally Posted by lyndonashmore
But they are the same effect Papageno, only in glass the electrons don't recoil because they are fixed in a crystal lattice. In the plasma of space the electrons recoil on absorption and re-emission so energy is lost to the electron. Photon loses energy, frequency reduces wavelength increases. It is redshifted. easy.
I wouldn't in my wildest dreams call myself a physicist, but I have a question. How does the photon loose energy to the plasma? I think I understand how your rebounding mechanism works, but I don't understand how the energy is lost, or where it goes. Considering the photon output of your average galaxy, I would have thought that the amount of energy being dumped into this IG plasma would be enormous!
No, you are wrong. You are a physicist with questions like this.
The energy lost is re-radiated as the CMB. that is why there more CMB photons than any other.
Cheers,
Lyndon
PS tell me where to send the cheque!
  #34 (permalink)  
Old 10-May-2005, 10:44 PM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by lyndonashmore
A photon undergoing compton scatter will be deflected and thus be deviated fropm its orignal path and thus 'miss' the earth. The only photons we receive come direct - as in light coming through a transparent medium. They are absorbed and re-emitted in a straight line and lose energy by the electrons recoiling.
It is thus not compton.
It's not anything. The whole effect is sheer invention, borrowing conflicting notions from different process. No such effect is ever seen.

The effect of photons bouncing from a recoiling electron is called Compton effect. It scatters the photon, so can't explain cosmological redshift. The Lyndon effect borrows redshift from the Compton effect.

The Mossbauer effect involves electrons very tightly bound into a lattice, so that there is no recoil. It's a remarkable effect allowing detection of photons with exactly the right frequency to excite bound electrons and leave nothing over for recoil. There is no scattering... and no redshift. The Lyndon effect borrows no scattering from the Mossbauer effect.

Transmission of light in a transparent medium involves the passage of light being slowed by interaction with the medium. The nature of interaction is sometimes thought of as electrons holding the photon momentarily before releasing it to continue. This glosses over a few bits of the usual quantum mechanical weirdness, but it's a fair analogy for a starting explanation. The light slows, but there is no redshift since the frequency remains the same, and light returns to the same wavelength on leaving the medium. The Lyndon effect borrows straight line transmission from transparent mediums, and also the lack of a strong frequency dependence seen in Mossbauer effect.

The transparent medium gambit is used by other tired light advocates as well, conflating the instantaeous change in velocity on entering the medium with the gradual and cummulative loss of energy in a tired light model.

There's no physics in any of this. Redshift by a loss of energy requires a transfer of momentum as well; and since momentum is a vector this means scatter. The only way to have no scatter is for the electron to be confined to move in exactly the same direction as the photon. This does not happen for electrons in a very thin plasma, with one electron every cubic meter or so.

Cheers -- Sylas
  #35 (permalink)  
Old 11-May-2005, 09:45 AM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by akirabakabaka
Glad to see a new discussion about this. Still making my way through the other thread, almost done...

Quote:
Originally Posted by papageno
It is Compton effect, and if you look it up, you will see that if the photon does not change direction in the scattering event, the wavelength does not change, no matter what the initial momentum of the electron is.**
I was under the impression that Compton Effect implied a change of direction and loss of energy. Can theta = 0? That is, can Compton scatter occur without a loss of energy? I can't find an example of such a case.
Yes, energy loss occurs when the direction of propagation of the scattered photon changes.
If it does not change, there is no energy loss.


Quote:
Originally Posted by akirabakabaka
Compton applies to bound electrons, can you apply it to a 'free' electron in plasma?
The Compton effect you mention happens with X-rays.
Photons in X-rays are energetic enough and localized enough to resolve the structure of an atom.
These photons can "see" the electrons in an atom as distinct particles. Also, the high energy makes the binding energy of the electrons to the nucleus much less relevant (the energy of an X-ray photon is of the order of the ionization energy of an atom).
This does not happen for photons of visible light: the wavelength is orders of magnitude larger than the size of an atom, and electrons cannot be resolved. And the energy is typically too low to compete with the binding energy.
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  #36 (permalink)  
Old 11-May-2005, 10:04 AM
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Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by papageno
When the photon is "off-resonance", (electrons+nucleus) act as a classical electric dipole.
Feynman talks about "electron picking up photons" because the electron is the most "mobile" part of the system (electron+nucleus).
It still an interaction between light and atoms.
It is not an interaction with free particles as in a plasma.
This is the point you keep missing.
I don’t ‘keep missing’ anything. The charges interact by long range coulomb forces. In Papageno’s world, how far apart do electrons protons have to be before there is no forces acting between them and they are free?
Go ahead and provide quantitative estimates that show that the interaction energy between charged particles in a low-density plasma is comparable to the kinetic energy of the particles.

Hint: the interaction energy is much less than the kinetic energy, otherwise the particles in a plasma would recombine into neutral atoms.
The fact that it is a plasma already tells you that the motion of the particles is dominated by the kinetic energy (and this is Newtonian Mechanics 101), and the interaction energy is too small to have any relevant effect (the other particles are too far away).
The only effect of the long-range Coulomb interaction are the plasma oscillations.

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by papageno
I am not talking here about glass, but about plasma, which is different.
It is your "tired light theory" that envisions the light traveling through IG plasma as a series of scattering events.
Yes, just as happens in glass and by the same interaction
No, it happens only in glass.
And these "scattering" events are just absorption-emission of photons, where the electromagnetic wave polarizes temporarily neutral atoms.


Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by papageno
Your "double Mossbauer effect" is an ad hoc assumption, because you found out that Compton scattering does not yield the result you were hoping for.
However, your "double Mossbauer effect" is not something that would actually happen in a plasma.
It is well known and documented that systems of electrons recoil on absorbing and re-emitting photons. This is not ‘ad hoc’ but proven physics.
"Systems of electrons" bound to nuclei.
Every single source you refer explains this, but you keep missing it.

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by papageno
Distance effects: the closer the object, the larger the blurring.
It is a statistical effect: the lower the number of scattering events, the stronger the relative effect of fluctuations in the number of these scattering effects.
Typically Doppler effect produces broadening of spectral lines if you have a gas emitting light (like a lamp).
But one doesn’t get ‘cosmological’ redshifts in nearby galaxies. They have to be in the ‘Hubble flow’ which is several million light years away. The Bb says its ‘local gravitational effects’ I say it could be that but I think it is statistical.
You "think"?
Where is the evidence?

Quote:
Originally Posted by lyndonashmore
Consequently either your point doesn’t apply if it is gravitational, or we are in agreement in that one doesn’t see redshifts because you need a large statistical sample before they are noticeable.
You are trying to evade the point.
The main parameter in your "tired light effect" is the number of scattering events.
Shows us that the red-shifts observed agree with the statistics of these scattering events.

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by papageno
Anyway, how do you get a red-shift which is the same for all observations of the same object?
Sigh! See my website I work it all out.
So, you cannot explain.
How did you work it out?

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by papageno
You do not understand.
The electrons do not need to oscillate back forth, in order for the charge density to oscillate.
That's why I brought up the analogy with sound.
And they do, a displaced electron in a plasma performs SHM about it’s ‘mean’ position.
Wrong!
In a plasma, the motion of an electron is dominated by its kinetic energy: it is not oscillating back and forth about a "mean position".
The only thing oscillating is the charge density (not the charge carriers).


Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by papageno
Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by papageno
Do you remember my analogy with sound?
Sound waves in air are oscillations in the density of air molecules.
However, single molecules do not oscillate back and forth.
not the same.
Of course you do not explain what is wrong with my analogy
What is wrong with your analogy is that atoms in air are electrically neutral.
You miss the point of the analogy.
The analogy is limited to:

air molecules --> charge carriers
air density --> charge density

That's it, it does not go any further.

Quote:
Originally Posted by lyndonashmore
There are no electrical forces between them so they have to literally bump into each other to interact. Hence you get ‘shock waves’. In plasma there are electrical forces which vary with distance and so they provide restoring forces which enable the electrons to perform SHM.
Wrong.
As has been explained to you many times, in plasma you can distinguish what happens to single charge carriers (electrons) from what happens to the charge density.
The electrons fly around free as birds, the charge density oscillates.


(Undergraduate students get the distinction between charge and charge carriers.)
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  #37 (permalink)  
Old 11-May-2005, 10:29 AM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by papageno
The plasma oscillations occur on length-scales that are much large than the wavelength of a visible-light photon, and would not have any effect on photon-electron scattering.
These plasma oscillations are oscillations in the charge density of the plasma, and are not the result of particles oscillating about some point.
I'd like to examine this a bit further.

Since plasma clouds are homogeneous, the equilibrium density of any given Debye sphere will be similar. We can see in the Mursula paper cited by lyndonashmore that all of the equations describing plasma frequency are in terms of single electrons and electron/ion densities. At no point is the 'entire plasma' taken into account.
From page 6 of that paper, where it starts Basic properties of a plasma:
Quote:
Originally Posted by Mursula
A substance is a plasma if it contains sufficiently many free charged particles (e.g., electrons and ions) so that their mutual electromagnetic interactions have an essential effect on the dynamics of the system and cause the system to behave collectively.
What do you think "free charged particles" means?

By the way, I think I already explained in the other thread where I do not agree with Mursula's explanations.
Not making a clear distinction between charge carriers and charge can give rise to confusions (as happens with Ashmore).


Quote:
Originally Posted by akirabakabaka
While papageno keeps asserting that the oscillation takes place in the charge density of the entire plasma, this cannot be true. The oscillation is a localized effect considered in terms of the Debye sphere. If the whole plasma was reacting to charge density perturbations, then the whole plasma would become polarized and it would no longer be a plasma.
Why?
The Debye length has to do with screening (relatively short-range).
Plasma oscillations have to with long-range collective behavior.


Quote:
Originally Posted by akirabakabaka
I believe that the oscillations resulting from photon-electron collisions are meant to be confined within the Debye sphere of the colliding electron.
Why do you think so?
If Coulomb interaction is long-range, how would you confine the oscillations?
Mind that the Debye sphere is just a volume around each particle.


Quote:
Originally Posted by akirabakabaka
We are dealing with an extremely low density hot plasma (not hot enough to be relativistic) so oscillations will not propagate waves at lengths greater than the Debye sphere.
Why not?
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  #38 (permalink)  
Old 11-May-2005, 10:30 AM
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Originally Posted by lyndonashmore
But one doesn’t get ‘cosmological’ redshifts in nearby galaxies. They have to be in the ‘Hubble flow’ which is several million light years away.
I don't get what you are trying to say here. Most nearby galaxies are several million light years away. The Hubble flow is not restricted to a small area but is a general principle. And most nearby galaxies have cosmological redshifts (or are you using a different definition?).

This is a nice and easy basic explanation: The expanding universe.
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  #39 (permalink)  
Old 11-May-2005, 10:34 AM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by papageno
The plasma oscillations occur on length-scales that are much larger than the wavelength of a visible-light photon, and would not have any effect on photon-electron scattering.
Just noticed a possible discrepancy here. The photon-electron collision causes the oscillation. It seems here you are implying it should be the other way around, that the oscillations should be effecting the collision, which is contrary to Ashmore's tired-light model.
Ashmore needs these oscillations for the electron to lose energy while it is "scratching its head" with the photon in his pocket.
Of course he does not explain how that would work, since the time it takes for the electron to "re-emit" the photon is very short compared to the typical time-scales of plasma oscillations.

By the way, what is the context of the quote from me?
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  #40 (permalink)  
Old 11-May-2005, 10:36 AM
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Quote:
Originally Posted by akirabakabaka
In the IG plasma case, the photon collision is with a single electron, not a a rigid solid. So the electron absorbs the photon, takes some momentum, then emits it, this time in the same direction it was travelling initially. Here I have some questions for Ashmore's model.
You have to consider conservation of both energy and momentum.
Ashmore needs some external force in order for the electron to lose energy, otherwise the photon comes out with the same energy.
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  #41 (permalink)  
Old 11-May-2005, 10:39 AM
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Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by TheAtomium
Quote:
Originally Posted by lyndonashmore
But they are the same effect Papageno, only in glass the electrons don't recoil because they are fixed in a crystal lattice. In the plasma of space the electrons recoil on absorption and re-emission so energy is lost to the electron. Photon loses energy, frequency reduces wavelength increases. It is redshifted. easy.
I wouldn't in my wildest dreams call myself a physicist, but I have a question. How does the photon loose energy to the plasma? I think I understand how your rebounding mechanism works, but I don't understand how the energy is lost, or where it goes. Considering the photon output of your average galaxy, I would have thought that the amount of energy being dumped into this IG plasma would be enormous!
No, you are wrong. You are a physicist with questions like this.
The energy lost is re-radiated as the CMB. that is why there more CMB photons than any other.
Cheers,
Lyndon
PS tell me where to send the cheque!
So you should not have problems in calculating the spectrum of CMB.
Well, where is it?
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  #42 (permalink)  
Old 11-May-2005, 11:31 AM
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Quote:
Originally Posted by Fram
Quote:
Originally Posted by lyndonashmore
But one doesn’t get ‘cosmological’ redshifts in nearby galaxies. They have to be in the ‘Hubble flow’ which is several million light years away.
I don't get what you are trying to say here. Most nearby galaxies are several million light years away. The Hubble flow is not restricted to a small area but is a general principle. And most nearby galaxies have cosmological redshifts (or are you using a different definition?).

This is a nice and easy basic explanation: The expanding universe.
No, For galaxies to be in the ‘Hubble flow’ and follow v = Hd etc they have to be several million light years away otherwise it doesn’t work.
Quote:
in galaxies around us, the Hubble flow is seen starting from about 1-2 Mpc (3 to 6 million light years) away and is seen, onwards and outwards, as far as one cares to look.
I believe this is part local gravity and part statistical. I wish I could find the reference (I will have to look) but this is one of the first thing that set me off on an alternative Bb theory. There was this set of spectra from galaxies further and further away, and what happened was the lines were more distinct the further away the galaxies were. The only thing that does this is statistics.
Cheers,
Lyndon
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Old 11-May-2005, 01:17 PM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by Sylas
Quote:
Originally Posted by lyndonashmore
A photon undergoing compton scatter will be deflected and thus be deviated fropm its orignal path and thus 'miss' the earth. The only photons we receive come direct - as in light coming through a transparent medium. They are absorbed and re-emitted in a straight line and lose energy by the electrons recoiling.
It is thus not compton.
It's not anything. The whole effect is sheer invention, borrowing conflicting notions from different process. No such effect is ever seen.
Oh yes it has. It is called redshift.

Quote:
The effect of photons bouncing from a recoiling electron is called Compton effect. It scatters the photon, so can't explain cosmological redshift. The Lyndon effect borrows redshift from the Compton effect.
Are you saying that light travels through glass by repeated Compton scatering? Who is the crank here?

Quote:
The Mossbauer effect involves electrons very tightly bound into a lattice, so that there is no recoil. It's a remarkable effect allowing detection of photons with exactly the right frequency to excite bound electrons and leave nothing over for recoil. There is no scattering... and no redshift. The Lyndon effect borrows no scattering from the Mossbauer effect.
Fine so bound electrons do not recoil. So loosely bound electrons in a plasma will recoil. exactly my point Sylas. Glad we got that sorted. Lyndon effect, yes, I like that.

Quote:
Transmission of light in a transparent medium involves the passage of light being slowed by interaction with the medium. The nature of interaction is sometimes thought of as electrons holding the photon momentarily before releasing it to continue. This glosses over a few bits of the usual quantum mechanical weirdness, but it's a fair analogy for a starting explanation. The light slows, but there is no redshift since the frequency remains the same, and light returns to the same wavelength on leaving the medium. The Lyndon effect borrows straight line transmission from transparent mediums, and also the lack of a strong frequency dependence seen in Mossbauer effect.
Good we are getting somewhere Sylas says there is a delay between absorption and re-emisssion as I keep saying. But they do not recoil because as Sylas said above they are tightly bound electrons in glass Hence Mossbauer. In IG space the energy is lost in the electrons recoiling so it can't return to its original wavelength.

Quote:
The transparent medium gambit is used by other tired light advocates as well, conflating the instantaeous change in velocity on entering the medium with the gradual and cummulative loss of energy in a tired light model.
This is because it is correct and happens all the time. In Tired light we do not need any 'new physics' as it is all around us when light travels through glass.
Quote:
There's no physics in any of this. Redshift by a loss of energy requires a transfer of momentum as well; and since momentum is a vector this means scatter. The only way to have no scatter is for the electron to be confined to move in exactly the same direction as the photon. This does not happen for electrons in a very thin plasma, with one electron every cubic meter or so.
Come off it, Sylas, even you must have heard of conservation of linear momentum which happens here.
Cheers,
Lyndon
  #44 (permalink)  
Old 11-May-2005, 01:26 PM
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Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by TheAtomium
I wouldn't in my wildest dreams call myself a physicist, but I have a question. How does the photon loose energy to the plasma? I think I understand how your rebounding mechanism works, but I don't understand how the energy is lost, or where it goes. Considering the photon output of your average galaxy, I would have thought that the amount of energy being dumped into this IG plasma would be enormous!
No, you are wrong. You are a physicist with questions like this.
The energy lost is re-radiated as the CMB. that is why there more CMB photons than any other.
Cheers,
Lyndon
PS tell me where to send the cheque!
Like I said I don't know much about this side of physics so please understand if I'm asking questions that have obvious answers.

By what process does the photon loose energy to the electron? Does the electron just say I'll have some of that, strip the electron of some energy, and send it on its way? If this is right, then when does the electron blip out some microwave (CMB) energy?

Or is it lost in the 'rebounding' part where some momentum is transfered into the matrix of plasma electrons*? In that case how is the energy then re-emitted as microwave energy?

Where does the SHM motion of plasma electrons come from? Is it because a displaced electron will want to slide back to a point of zero net electric force (terminology ops?

Again I don't know all that much about physics so I might be making some terrible assumptions and misjudgements ops:

*I use the term loosely to describe how I understand your model of plasma electrons. It seems like Papageno's model is like air molecules travelling freely at huge speeds (while the net speed is much less), while yours sounds more like raisins in some jelly.
  #45 (permalink)  
Old 11-May-2005, 01:43 PM
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Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by Fram
Quote:
Originally Posted by lyndonashmore
But one doesn’t get ‘cosmological’ redshifts in nearby galaxies. They have to be in the ‘Hubble flow’ which is several million light years away.
I don't get what you are trying to say here. Most nearby galaxies are several million light years away. The Hubble flow is not restricted to a small area but is a general principle. And most nearby galaxies have cosmological redshifts (or are you using a different definition?).

This is a nice and easy basic explanation: The expanding universe.
No, For galaxies to be in the ‘Hubble flow’ and follow v = Hd etc they have to be several million light years away otherwise it doesn’t work.
Quote:
in galaxies around us, the Hubble flow is seen starting from about 1-2 Mpc (3 to 6 million light years) away and is seen, onwards and outwards, as far as one cares to look.
I believe this is part local gravity and part statistical. I wish I could find the reference (I will have to look) but this is one of the first thing that set me off on an alternative Bb theory. There was this set of spectra from galaxies further and further away, and what happened was the lines were more distinct the further away the galaxies were. The only thing that does this is statistics.
Cheers,
Lyndon
Ah, so 'nearby galaxies' = the Local Group, and the Hubble Flow starts several million lightyears away. From the link you gave:
Quote:
The Hubble flow, or general expansion of the universe discovered by Edwin Hubble in the 1920's, appears immedeately beyond the edge of the Local Group, at about 1.5 Mpc from our Milky Way.
Things would be easier if you wrote a bit clearer, Lyndon. I guess you can appreciate me saying this as you were so kind to point me to some 'technical term' yesterday as a translation for a term I hadn't even used. I will not call it 'sloppy work', as you don't seem to like that very much...
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Old 11-May-2005, 02:06 PM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by Sylas
]There's no physics in any of this. Redshift by a loss of energy requires a transfer of momentum as well; and since momentum is a vector this means scatter. The only way to have no scatter is for the electron to be confined to move in exactly the same direction as the photon. This does not happen for electrons in a very thin plasma, with one electron every cubic meter or so.
Come off it, Sylas, even you must have heard of conservation of linear momentum which happens here.
Cheers,
Lyndon
Which is still a vector operation Lyndon. It just happens to occur in a one dimensional system (two if you include time). Unfortunately, we live in a four-dimensional universe (time included) so this special case really can't apply here. As others have pointed out you give no mechanism that constrains the electrons in the plasma to move only in this single dimension.
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Old 11-May-2005, 04:51 PM
lyndonashmore lyndonashmore is offline
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by Eta C
Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by Sylas
]There's no physics in any of this. Redshift by a loss of energy requires a transfer of momentum as well; and since momentum is a vector this means scatter. The only way to have no scatter is for the electron to be confined to move in exactly the same direction as the photon. This does not happen for electrons in a very thin plasma, with one electron every cubic meter or so.
Come off it, Sylas, even you must have heard of conservation of linear momentum which happens here.
Cheers,
Lyndon
Which is still a vector operation Lyndon. It just happens to occur in a one dimensional system (two if you include time). Unfortunately, we live in a four-dimensional universe (time included) so this special case really can't apply here. As others have pointed out you give no mechanism that constrains the electrons in the plasma to move only in this single dimension.
No its fine Eta C, you forget that there are restraining forces acting on our electrons in the plasma from other charges in the plasma which restrict sideways motion. That is the restoring forces that we are talking about that enable it to perform SHm stop it moving sideways.
Even your beloved Compton scater allows the photon to come back on itself - conservation of linear momentum
Cheers,
Lyndon
Trust me on this one.
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Old 11-May-2005, 04:52 PM
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Default Re: Ashmore's "paradox" Reloaded.

I have no expectation of convincing Lyndon of anything here. I don't regard this as a debate. I am content for Lyndon to think whatever he likes, and to place my position on the table for comparison.

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by Sylas
It's not anything. The whole effect is sheer invention, borrowing conflicting notions from different process. No such effect is ever seen.
Oh yes it has. It is called redshift.
Lyndon's effect is not called redshift. It is purported to lead to a redshift, but the Lyndon effect is a particular kind of interaction between photons and electrons that does not exist in real life.

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by Sylas
The effect of photons bouncing from a recoiling electron is called Compton effect. It scatters the photon, so can't explain cosmological redshift. The Lyndon effect borrows redshift from the Compton effect.
Are you saying that light travels through glass by repeated Compton scatering? Who is the crank here?
The crank here is the person who simply invents non-sequiturs. I said nothing here about glass. Electrons in glass don't recoil, and this is why the photons emerge from glass with their original energy; no redshift, and no recoil, and no Compton scattering.

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by Sylas
The Mossbauer effect involves electrons very tightly bound into a lattice, so that there is no recoil. It's a remarkable effect allowing detection of photons with exactly the right frequency to excite bound electrons and leave nothing over for recoil. There is no scattering... and no redshift. The Lyndon effect borrows no scattering from the Mossbauer effect.
Fine so bound electrons do not recoil. So loosely bound electrons in a plasma will recoil. exactly my point Sylas. Glad we got that sorted. Lyndon effect, yes, I like that.
Yes, electrons in plasma recoil. That's why you get the Compton effect.

In real physics, interactions with plasma involve redshift, recoil and scattering, as in the Compton effect. And in a rigid lattice you can have have transmission with no redshift, no recoil, and no scattering, as in the Mossbauer effect.

Lyndon invents a new physically impossible reaction by combing Compton-like redshift with Mossbauer-like scattering (no scattering). But I am intrigued that Lyndon actually says that the electrons in the plasma recoil in this alleged reaction. The physical implications of this are violation of basic conservation laws.

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by Sylas
Transmission of light in a transparent medium involves the passage of light being slowed by interaction with the medium. The nature of interaction is sometimes thought of as electrons holding the photon momentarily before releasing it to continue. This glosses over a few bits of the usual quantum mechanical weirdness, but it's a fair analogy for a starting explanation. The light slows, but there is no redshift since the frequency remains the same, and light returns to the same wavelength on leaving the medium. The Lyndon effect borrows straight line transmission from transparent mediums, and also the lack of a strong frequency dependence seen in Mossbauer effect.
Good we are getting somewhere Sylas says there is a delay between absorption and re-emisssion as I keep saying. But they do not recoil because as Sylas said above they are tightly bound electrons in glass Hence Mossbauer. In IG space the energy is lost in the electrons recoiling so it can't return to its original wavelength.
And there you have it. Lyndon takes the properties he needs from interactions in a rigid lattice... no scattering... and transfers with to a highly rarified plasma without any justification. The reason you get straight line transmission in a real Mossbauer effect is precisely because of the lack of recoil. As soon as you move to the plasma, you get recoil, and hence scattering. This can't be avoided due to the need for conservation of momentum and energy.

Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by Sylas
There's no physics in any of this. Redshift by a loss of energy requires a transfer of momentum as well; and since momentum is a vector this means scatter. The only way to have no scatter is for the electron to be confined to move in exactly the same direction as the photon. This does not happen for electrons in a very thin plasma, with one electron every cubic meter or so.
Come off it, Sylas, even you must have heard of conservation of linear momentum which happens here.
It is precisely because I have heard of and actually understand and apply the conservation of momentum and energy that can I recognize immediately why the Lyndon effect is a violation of basic school level physics.

The Lyndon effect cannot conserve momentum, or it cannot conserve energy. To prove this, assume a Lyndon interaction between a photon and electron with conservation of energy and momentum, and derive a contradiction.

You have an initial photon, with frequency f, and hence with energy hf and momentum hf/c.

There is some kind of interaction with an electron, from which the photon emerges redshifted to frequency F. This means that the electron must have a boost in energy of h(f-F), to conserve energy.

In the Lyndon effect, there is no scattering of the photon, so the direction for the photon is as before. The recoil in the electron must be along the same line, or else conservation of momentum is violated.

Consider a case where the electron is initially at rest. You can always reduce to this case by a simple change of reference frame. By conservation of energy, the electron ends up with a small amount of kinetic energy E equal to h(f-F). Since there is no scatter and everything is straight line motion, we can also infer that the momentum difference in the photon is the momentum p of the electron, being h(f-F)/c.

Hence E = pc.

For those used to Newtonian physics, which would actually apply here for small velocities, we have E = mv^2/2 and p = mv, where v is the electron velocity.

E = pc becomes mv^2 = 2mvc, or v*(v-2c) = 0. That is, either v is zero (no recoil, no redshift) or v is twice the speed of light (not possible).

If we use relativity, we use the total energy equation to get
(mc^2)^2 + (pc)^2 = (mc^2 + E)^2 = (mc^2 + pc)^2
and hence
0 = 2mpc^3
Hence p is zero. The final electron must have zero momentum; no recoil, no redshift.

This isn't hard. It's very elementary. But I don't think Lyndon even understands the equations, and years of attempts to explain it to him have had no effect.

Cheers -- Sylas
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Old 11-May-2005, 04:58 PM
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Quote:
Originally Posted by Fram
Quote:
Originally Posted by lyndonashmore
Quote:
Originally Posted by Fram
Quote:
Originally Posted by lyndonashmore
But one doesn’t get ‘cosmological’ redshifts in nearby galaxies. They have to be in the ‘Hubble flow’ which is several million light years away.
I don't get what you are trying to say here. Most nearby galaxies are several million light years away. The Hubble flow is not restricted to a small area but is a general principle. And most nearby galaxies have cosmological redshifts (or are you using a different definition?).

This is a nice and easy basic explanation: The expanding universe.
No, For galaxies to be in the ‘Hubble flow’ and follow v = Hd etc they have to be several million light years away otherwise it doesn’t work.
Quote:
in galaxies around us, the Hubble flow is seen starting from about 1-2 Mpc (3 to 6 million light years) away and is seen, onwards and outwards, as far as one cares to look.
I believe this is part local gravity and part statistical. I wish I could find the reference (I will have to look) but this is one of the first thing that set me off on an alternative Bb theory. There was this set of spectra from galaxies further and further away, and what happened was the lines were more distinct the further away the galaxies were. The only thing that does this is statistics.
Cheers,
Lyndon
Ah, so 'nearby galaxies' = the Local Group, and the Hubble Flow starts several million lightyears away. From the link you gave:
Quote:
The Hubble flow, or general expansion of the universe discovered by Edwin Hubble in the 1920's, appears immedeately beyond the edge of the Local Group, at about 1.5 Mpc from our Milky Way.
Things would be easier if you wrote a bit clearer, Lyndon. I guess you can appreciate me saying this as you were so kind to point me to some 'technical term' yesterday as a translation for a term I hadn't even used. I will not call it 'sloppy work', as you don't seem to like that very much...
OK Fram, sorry about not being clear. I will type this slowly to help you read it.
A single photon of light will make one collision every 70,000 light year or so. In 5 million ly it will make about 75 collisions and this is when the stats start to work. interestingly enough this distance 5 million ly is equivalent to the 'blooming' on your camera lens. That works ok so the tired light theory works ok at this distance.
Cheers,
Lyndon.
PS sorry about the typing slowly bit - couldn't resist it!
  #50 (permalink)  
Old 11-May-2005, 06:05 PM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by lyndonashmore
No its fine Eta C, you forget that there are restraining forces acting on our electrons in the plasma from other charges in the plasma which restrict sideways motion. That is the restoring forces that we are talking about that enable it to perform SHm stop it moving sideways.
Even your beloved Compton scater allows the photon to come back on itself - conservation of linear momentum
Provide quantitative estimates for these "restraining forces" and show that they make an electron oscillate about a position.

And don't come up with out-of-context quotes from sources that deal with high-powered laser in high-density plasma, as you have done before.
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Old 11-May-2005, 06:07 PM
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Quote:
Originally Posted by lyndonashmore
interestingly enough this distance 5 million ly is equivalent to the 'blooming' on your camera lens.
I haev a feeling we will never understand one another. What is the equivalence between a distance and 'blooming' on my camera lens?
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Old 11-May-2005, 06:45 PM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by papageno
Quote:
Originally Posted by lyndonashmore
No its fine Eta C, you forget that there are restraining forces acting on our electrons in the plasma from other charges in the plasma which restrict sideways motion. That is the restoring forces that we are talking about that enable it to perform SHm stop it moving sideways.
Even your beloved Compton scater allows the photon to come back on itself - conservation of linear momentum
Provide quantitative estimates for these "restraining forces" and show that they make an electron oscillate about a position.

And don't come up with out-of-context quotes from sources that deal with high-powered laser in high-density plasma, as you have done before.
OK... papageno I have quietly followed this discussion through many incarnations and have to ask; does he listen to anything you say?? I only ask because the longer this goes on the more it seems that you are having to repeat the same ideas over and over in different words.
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Old 11-May-2005, 06:56 PM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by Lurker
Quote:
Originally Posted by papageno
Quote:
Originally Posted by lyndonashmore
No its fine Eta C, you forget that there are restraining forces acting on our electrons in the plasma from other charges in the plasma which restrict sideways motion. That is the restoring forces that we are talking about that enable it to perform SHm stop it moving sideways.
Even your beloved Compton scater allows the photon to come back on itself - conservation of linear momentum
Provide quantitative estimates for these "restraining forces" and show that they make an electron oscillate about a position.

And don't come up with out-of-context quotes from sources that deal with high-powered laser in high-density plasma, as you have done before.
OK... papageno I have quietly followed this discussion through many incarnations and have to ask; does he listen to anything you say?? I only ask because the longer this goes on the more it seems that you are having to repeat the same ideas over and over in different words.
Actually he does not listen.
You might have noticed that Ashmore has not changed his arguments since the beginning of the other thread.
He uses the same quotes, even though the context has been explained to him in excruciating detail.

Instead of actually trying to understand the criticism, he prefers the "broken record" tactic, hoping that critics will get tired and leave.
He probably is convinced that he actually knows what he is talking about, despite the fact that on this board have pointed out and tried to correct his mistakes.

The only reason I am not giving up, is for people that have not followed this thread and might think that there is something to Ashmore's ideas (as akirabakabaka, apparently).
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Old 12-May-2005, 10:15 AM
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Quote:
Originally Posted by Fram
Quote:
Originally Posted by lyndonashmore
interestingly enough this distance 5 million ly is equivalent to the 'blooming' on your camera lens.
I haev a feeling we will never understand one another. What is the equivalence between a distance and 'blooming' on my camera lens?
I hope you have at least read Ashmore's paper describing his theory?

He is making an analogy here (which he explained several posts ago). Since Ashmore's tired-light mechanism is based on light hitting electrons in IG plasma, he calculated how often this would happen. It turns out that it happens every 70,000 lightyears or so, depending on the density of the IG plasma.

In his ill-fated analogy, he is equating the number of collisions of photons with particles. He has calculated that the lens of a camera is about equal to 5mly worth of low density IG plasma in this respect.

Therefore to observe Ashmore's effect, you need a sample of light which has travelled sufficiently far to have had enough collisions to make a noticeable redshift. This agrees with observation to a certain degree. (read his website, all of this is explained!)
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Old 12-May-2005, 10:33 AM
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Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by Fram
Quote:
Originally Posted by lyndonashmore
interestingly enough this distance 5 million ly is equivalent to the 'blooming' on your camera lens.
I haev a feeling we will never understand one another. What is the equivalence between a distance and 'blooming' on my camera lens?
I hope you have at least read Ashmore's paper describing his theory?
I did read it.
Unfortunately it has only the appearance of a scientific paper, not the substance.

Quote:
Originally Posted by akirabakabaka
He is making an analogy here (which he explained several posts ago). Since Ashmore's tired-light mechanism is based on light hitting electrons in IG plasma, he calculated how often this would happen. It turns out that it happens every 70,000 lightyears or so, depending on the density of the IG plasma.
Unfortunately for Ashmore, IG plasma is nothing like glass (plasma has free charged particles, glass has neutral atoms bound in a lattice).
So his analogy is inappropriate.

Quote:
Originally Posted by akirabakabaka
In his ill-fated analogy, he is equating the number of collisions of photons with particles. He has calculated that the lens of a camera is about equal to 5mly worth of low density IG plasma in this respect.
Except that he assumed a uniform density of particles, and that the red-shift is the same for each collision.
Both are over-simplified assumptions.

Quote:
Originally Posted by akirabakabaka
Therefore to observe Ashmore's effect, you need a sample of light which has travelled sufficiently far to have had enough collisions to make a noticeable redshift.
Since the number of collisions is the important parameter, we do not need IG plasma to test this "effect".
We just need a sufficiently dense plasma in a lab (or even a piece glass, if you believe Ashmore), shine light through it and measure the red-shift.
Unfortunately for Ashmore, such red-shift has never been observed in experiments (and that's not because they were not accurate enough).

Quote:
Originally Posted by akirabakabaka
This agrees with observation to a certain degree. (read his website, all of this is explained!)
Ashmore's explanations are wrong, as has been explained many times on this board.
He does not accept that he is wrong and won't get rid of his misconceptions.
I suggest you read carefully the sources of the quotes he provides (he has a bad habit of quoting sources out of context, with the result of misrepresenting them).
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  #56 (permalink)  
Old 12-May-2005, 10:37 AM
akirabakabaka akirabakabaka is offline
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Default Re: Ashmore's "paradox" Reloaded.

Let's take another stab at the heart of oscillating electrons, eh?

Quote:
Originally Posted by papageno
Quote:
Originally Posted by lyndonashmore
No its fine Eta C, you forget that there are restraining forces acting on our electrons in the plasma from other charges in the plasma which restrict sideways motion. That is the restoring forces that we are talking about that enable it to perform SHm stop it moving sideways.
Even your beloved Compton scater allows the photon to come back on itself - conservation of linear momentum
Provide quantitative estimates for these "restraining forces" and show that they make an electron oscillate about a position.

And don't come up with out-of-context quotes from sources that deal with high-powered laser in high-density plasma, as you have done before.
I don't believe anyone ever responded to me about this from my page1 post:

Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by papageno
These plasma oscillations are oscillations in the charge density of the plasma, and are not the result of particles oscillating about some point.***
The wiki defines 'plasma frequency' as 'the frequency with which electrons oscillate when their charge density is not equal to the ion charge density', and defines the terms of this equation as the density of electrons(n), the electric charge(e), and the mass of the electron (m). A clarification is also given:
Quote:
Note that the above formula is derived under the approximation that the ion mass is infinite. This is generally a good approximation, as the electrons are so much lighter than ions.
The first paragraph here states the plasma model precisely as lyndonashmore has been describing, restoring forces and all.
Quote:
In the simplest example of such a perturbation, the electrons might be offset from the less mobile (because of their mass) ions. The electrons, then, would execute simple harmonic motion about their equilibrium positions.
This more accurately describes a 'cold plasma' model where we can ignore the initial velocities of the particles. I am interested to know how SHM is described in a non-relativistic 'hot plasma' model such as we are dealing with.
I cannot find a description of 'plasma frequency' which does not say that the electrons themselves are oscillating. I'll put another nail in the coffin with http://www.plasmaphysics.org.uk/ which explains 'plasma frequency' as a collective electron displacement. Can we finally agree that electrons oscillate in plasma?

Also note the reference at the end to SHM in a 'cold plasma', where the initial velocities of the electrons can be ignored. I believe lyndonashmore has already cited several experiments which show SHM of electrons in lasers, or 'relativistic hot plasma'. Here is another one I randomly googled (there's lots). I have not seen any specific studies of SHM in non-relativistic hot plasma, but I don't see any reason to believe why they wouldn't react just as in the other conditions at each end of the relativity scale.

I could have explained all of this from plenty of other papers already cited in these discussions, but papageno has apparently dismissed them all?

Quote:
Originally Posted by papageno
Quote:
Originally Posted by lyndonashmore
I don’t ‘keep missing’ anything. The charges interact by long range coulomb forces. In Papageno’s world, how far apart do electrons protons have to be before there is no forces acting between them and they are free?
Go ahead and provide quantitative estimates that show that the interaction energy between charged particles in a low-density plasma is comparable to the kinetic energy of the particles.

Hint: the interaction energy is much less than the kinetic energy, otherwise the particles in a plasma would recombine into neutral atoms.
The fact that it is a plasma already tells you that the motion of the particles is dominated by the kinetic energy (and this is Newtonian Mechanics 101), and the interaction energy is too small to have any relevant effect (the other particles are too far away).
The only effect of the long-range Coulomb interaction are the plasma oscillations.
Regarding the claim that kinetic energy of hot plasma 'free' electrons dominates their motion, isn't is true that electron temperature provides the magnitude of their velocity but the direction is limited by the charge of nearby ions? (could the charge density be at equilibrium otherwise?) It is within this limited range of mobility that they are 'free'.

Any disturbance that causes the electron to move outside of this boundary disturbs the charge density and causes an oscillation of electrons. The restoring (Coulomb) force eventually restores the electrons into a distribution of equilibrium (not necessarily near where they started in a hot plasma). If the entire plasma's charge density were to oscillate, the entire plasma cloud would become polarized and would no longer be a plasma.
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Old 12-May-2005, 10:47 AM
akirabakabaka akirabakabaka is offline
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papageno, were you playing coy in pretending to not understand the analogy at all? You seem to have quite a good grasp of it!

Quote:
Originally Posted by papageno
Unfortunately for Ashmore, IG plasma is nothing like glass (plasma has free charged particles, glass has neutral atoms bound in a lattice).
So his analogy is inappropriate.
The analogy has nothing to do with the mechanism of how light propagates, just the number of collisions involved.

Quote:
Originally Posted by papageno
Quote:
Originally Posted by akirabakabaka
In his ill-fated analogy, he is equating the number of collisions of photons with particles. He has calculated that the lens of a camera is about equal to 5mly worth of low density IG plasma in this respect.
Except that he assumed a uniform density of particles, and that the red-shift is the same for each collision.
Both are over-simplified assumptions.
This is a good point, and is specifically taken into account on Ashmore's website.

Quote:
Originally Posted by papageno
Quote:
Originally Posted by akirabakabaka
Therefore to observe Ashmore's effect, you need a sample of light which has travelled sufficiently far to have had enough collisions to make a noticeable redshift.
Since the number of collisions is the important parameter, we do not need IG plasma to test this "effect".
We just need a sufficiently dense plasma in a lab (or even a piece glass, if you believe Ashmore), shine light through it and measure the red-shift.
Unfortunately for Ashmore, such red-shift has never been observed in experiments (and that's not because they were not accurate enough).
It has been explained to death why the redshift in Ashmore's model does not appear in either glass or dense plasma. The mass/density is too great for the photon to have much effect on it, so little energy is lost in the collisions.

Quote:
Originally Posted by papageno
Quote:
Originally Posted by akirabakabaka
This agrees with observation to a certain degree. (read his website, all of this is explained!)
Ashmore's explanations are wrong, as has been explained many times on this board.
He does not accept that he is wrong and won't get rid of his misconceptions.
I suggest you read carefully the sources of the quotes he provides (he has a bad habit of quoting sources out of context, with the result of misrepresenting them).
I would love to believe everyone who keeps telling me this issue is resolved, but if we are still claiming that electrons don't oscillate in plasma, then we have a long way to go!
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  #58 (permalink)  
Old 12-May-2005, 11:08 AM
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Default Re: Ashmore's "paradox" Reloaded.

Quote:
Originally Posted by akirabakabaka
I don't believe anyone ever responded to me about this from my page1 post:
Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by papageno
These plasma oscillations are oscillations in the charge density of the plasma, and are not the result of particles oscillating about some point.***
The wiki defines 'plasma frequency' as 'the frequency with which electrons oscillate when their charge density is not equal to the ion charge density',...
Quote:
Originally Posted by Wikipedia's first line from the link
In physics, plasma oscillations, often referred to as "Langmuir waves" or "plasma waves," are periodic oscillations of charge density in conducting media such as plasmas or metals.
Let me point out "charge density".

Quote:
Originally Posted by akirabakabaka
...and defines the terms of this equation as the density of electrons(n), the electric charge(e), and the mass of the electron (m). A clarification is also given:
Quote:
Note that the above formula is derived under the approximation that the ion mass is infinite. This is generally a good approximation, as the electrons are so much lighter than ions.
And also note:
Quote:
Originally Posted by Wikipedia, in the same link,
Consider a neutral plasma, consisting of a gas of positively charged ions and negatively charged electrons. If one displaces by a tiny amount all of the electrons with respect to the ions, the Coulomb force pulls back, acting as a restoring force.
Let me point out "If one displaces by a tiny amount all of the electrons with respect to the ions".

So, how does Wikipedia entry support Ashmore's idea of "restraining forces" in a plasma?

Quote:
Originally Posted by akirabakabaka
The first paragraph here states the plasma model precisely as lyndonashmore has been describing, restoring forces and all.
Quote:
In the simplest example of such a perturbation, the electrons might be offset from the less mobile (because of their mass) ions. The electrons, then, would execute simple harmonic motion about their equilibrium positions.
This more accurately describes a 'cold plasma' model where we can ignore the initial velocities of the particles. I am interested to know how SHM is described in a non-relativistic 'hot plasma' model such as we are dealing with.
Quote:
Originally Posted by W. S. Kurth
Plasma is a very hot gas in which the electrons have been stripped from atoms to form a gas of negatively charged electrons and positively charged ions.
Let me point out "to form a gas".
How do particles in a gas oscillate about an equilibrium position?
Particles are not bound to fixed position as in a crystal lattice.

Now, how do make the quote you provided agree with Wikipedia?
Are you sure Kurth is not referring to the overall charge densities when he says
Quote:
Originally Posted by W. S. Kurth
In a fully thermalized, equilibrium state, these electrons and ions would oscillate about their equilibrium positions.
where these "equilibrium positions" refer to the barycenter of positive and negative charge (which is what you find in textbooks).


Quote:
Originally Posted by akirabakabaka
I cannot find a description of 'plasma frequency' which does not say that the electrons themselves are oscillating. I'll put another nail in the coffin with http://www.plasmaphysics.org.uk/ which explains 'plasma frequency' as a collective electron displacement. Can we finally agree that electrons oscillate in plasma?
Let me point out "collective electron displacement".
It means that the whole lot of electrons are displaced at the same time.
This is nowhere near Ashmore's "effect", where a photon interacts with a single electron at a time.

Quote:
Originally Posted by akirabakabaka
Also note the reference at the end to SHM in a 'cold plasma', where the initial velocities of the electrons can be ignored. I believe lyndonashmore has already cited several experiments which show SHM of electrons in lasers, or 'relativistic hot plasma'.
As I already explained, the experiments that involve high-powered laser in high-density plasma are completely irrelevant to Ashmore's "theory", because he deal low-power light in low-density plasmas.


Quote:
Originally Posted by akirabakabaka
Here is another one I randomly googled (there's lots). I have not seen any specific studies of SHM in non-relativistic hot plasma, but I don't see any reason to believe why they wouldn't react just as in the other conditions at each end of the relativity scale.
I can see a reason why ultra-relativistic plasma has nothing to do with Ashmore's "theory".
The IG plasma is nowhere near of being relativistic., hence you cannot expect to act the same way.
If you think it does, provide evidence.

Quote:
Originally Posted by akirabakabaka
I could have explained all of this from plenty of other papers already cited in these discussions, but papageno has apparently dismissed them all?
Wrong.
I checked them, and found out that they do not agree with Ashmore' claims.
The fact that he keeps citing references that do not agree with him, only shows that he has no clue about what he is talking about.

Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by papageno
Quote:
Originally Posted by lyndonashmore
I don’t ‘keep missing’ anything. The charges interact by long range coulomb forces. In Papageno’s world, how far apart do electrons protons have to be before there is no forces acting between them and they are free?
Go ahead and provide quantitative estimates that show that the interaction energy between charged particles in a low-density plasma is comparable to the kinetic energy of the particles.

Hint: the interaction energy is much less than the kinetic energy, otherwise the particles in a plasma would recombine into neutral atoms.
The fact that it is a plasma already tells you that the motion of the particles is dominated by the kinetic energy (and this is Newtonian Mechanics 101), and the interaction energy is too small to have any relevant effect (the other particles are too far away).
The only effect of the long-range Coulomb interaction are the plasma oscillations.
Regarding the claim that kinetic energy of hot plasma 'free' electrons dominates their motion, isn't is true that electron temperature provides the magnitude of their velocity but the direction is limited by the charge of nearby ions? (could the charge density be at equilibrium otherwise?) It is within this limited range of mobility that they are 'free'.
How "nearby" are these ions?
How strong do they affect the motion of an electron?
Provide quantitative estimates instead of jumping to conclusions.

Quote:
Originally Posted by akirabakabaka
Any disturbance that causes the electron to move outside of this boundary disturbs the charge density and causes an oscillation of electrons.
And what happens when the electron is inside the boundaries?
What's the scale of IG plasma volumes?

Quote:
Originally Posted by akirabakabaka
The restoring (Coulomb) force eventually restores the electrons into a distribution of equilibrium (not necessarily near where they started in a hot plasma). If the entire plasma's charge density were to oscillate, the entire plasma cloud would become polarized and would no longer be a plasma.
Wrong.
Plasma oscillations are exactly oscillation in the charge density over length-scales comparable to the size of the plasma volume.
The whole plasma acts as a big honkin' electric dipole that oscillates.
Unfortunately for Ashmore, these oscillations do not affect the scattering of single photons on single electrons.
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  #59 (permalink)  
Old 12-May-2005, 11:15 AM
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Quote:
Originally Posted by akirabakabaka
papageno, were you playing coy in pretending to not understand the analogy at all? You seem to have quite a good grasp of it!

Quote:
Originally Posted by papageno
Unfortunately for Ashmore, IG plasma is nothing like glass (plasma has free charged particles, glass has neutral atoms bound in a lattice).
So his analogy is inappropriate.
The analogy has nothing to do with the mechanism of how light propagates, just the number of collisions involved.
Ashmore does not make an analogy between glass and plasma: he says that the mechanism is exactly the same.

Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by papageno
Quote:
Originally Posted by akirabakabaka
In his ill-fated analogy, he is equating the number of collisions of photons with particles. He has calculated that the lens of a camera is about equal to 5mly worth of low density IG plasma in this respect.
Except that he assumed a uniform density of particles, and that the red-shift is the same for each collision.
Both are over-simplified assumptions.
This is a good point, and is specifically taken into account on Ashmore's website.
How?

Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by papageno
Quote:
Originally Posted by akirabakabaka
Therefore to observe Ashmore's effect, you need a sample of light which has travelled sufficiently far to have had enough collisions to make a noticeable redshift.
Since the number of collisions is the important parameter, we do not need IG plasma to test this "effect".
We just need a sufficiently dense plasma in a lab (or even a piece glass, if you believe Ashmore), shine light through it and measure the red-shift.
Unfortunately for Ashmore, such red-shift has never been observed in experiments (and that's not because they were not accurate enough).
It has been explained to death why the redshift in Ashmore's model does not appear in either glass or dense plasma. The mass/density is too great for the photon to have much effect on it, so little energy is lost in the collisions.
Why would the mass/density be too great?
Ashmore's point is that the electron loses energy while it keep the photon in his pocket.
The higher the density, the larger the energy loss to the other particles.


Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by papageno
Quote:
Originally Posted by akirabakabaka
This agrees with observation to a certain degree. (read his website, all of this is explained!)
Ashmore's explanations are wrong, as has been explained many times on this board.
He does not accept that he is wrong and won't get rid of his misconceptions.
I suggest you read carefully the sources of the quotes he provides (he has a bad habit of quoting sources out of context, with the result of misrepresenting them).
I would love to believe everyone who keeps telling me this issue is resolved, but if we are still claiming that electrons don't oscillate in plasma, then we have a long way to go!
Unfortunately Nature does not care about Ashmore's misconceptions about plasma.
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  #60 (permalink)  
Old 12-May-2005, 12:56 PM
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Quote:
Originally Posted by akirabakabaka
Quote:
Originally Posted by Fram
Quote:
Originally Posted by lyndonashmore
interestingly enough this distance 5 million ly is equivalent to the 'blooming' on your camera lens.
I haev a feeling we will never understand one another. What is the equivalence between a distance and 'blooming' on my camera lens?
I hope you have at least read Ashmore's paper describing his theory?
I tried. I always have a hard time with numerology.
Quote:
Originally Posted by akirabakabaka
He is making an analogy here (which he explained several posts ago).
No. The blooming of the camera lens just appears here out of nowhere (the 5 million ly was mentioned before when he needed to clarify what he meant by nearby galaxies, as he again was very unclear), and comparing a visual effect with a distance is wrong. Lyndon clearly has a huge problem when it comes to explaining things in a comprehensible and logically consistent way, which is rather sad for someone trying to have a paradox and unit named after him.

Take this quote from his press release:
Quote:
If we convert the Hubble constant into SI units, 64 km/s per Mpc becomes 2.1exp(-18 ) per sec.
Where have all the units gone? Only the seconds are left!
Oh, I see, because he pulls the same trick in the next line,
Quote:
But what Ashmore found was that the quantity ‘hr/m per cubic metre’ (h is the planck constant, m is the mass of the electron and r is the classical radius of the electron) is also equal to 2.1exp(-18 ) per sec! Or, to put it another way, ‘hr/m per cubic metre’ in astronomical units is 64 km/s per Mpc – the Hubble constant.
This is plain gibberish and pure numerology, and thus hardly fit as the basis for a scientific theory. Add to this that the mechanism he describes is equally ridiculous (papageno explains this way better than I ever can), and you get an idea of why I have a problem with Ashmore's Hat of Tricks and with the way he expresses his ideas.

EDIT: I've put a space between the 8 and the ), becasue otherwise you get this smiley 8)
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