The problem here is that you do not know enough to understand what you read, and so you seriously misinterpret it. The standard, mainstream physics certainly does use electric fields to accelerate the particles. But the electric fields that do the accelerating are derived from the time variable magnetic fields, essentially via Faraday's Law. And the time variable magnetic field is derived from the electric fields of the charged particles of the solar plasma via the equations of dynamo theory.

So the basic process goes like this.
(1) Plasma in motion creates time varying magnetic field.
(2) Time varying magnetic field creates electric field.
(3) Electric field accelerates particles.

All of the scientists studying this problem know this process very well, so there is no reason for them to repeat it to each other, in papers they write to communicate with each other. Their papers consistently cast the problem in terms of the magnetic field, because in this case it is the magnetic field which is fundamental, and not the electric field. The electric field that does the particle accelerating is derived from the magnetic field, not the other way around. And since the magnetic field is relatively easy to observe, we simply start with the observed magnetic field, and work from there.

That's cool if the problem you are working on is the acceleration of solar wind particles, or perhaps the heating of the stellar corona. However, if you are working on the problem of generating the magnetic field in the first place, then assuming its existence is obviously not cool. So, the scientists working on that problem have to start with the detailed structure of the plasma (temperature, pressure, velocity, composition & etc.), and then model the generated magnetic field (including the back-reaction of the plasma to the magnetic field that it generated on itself). This is a much harder problem to approach observationally, since so much of the solar interior has been invisible, prior to the advent of helioseismology.

Perhaps you were thinking that mainstream science claims that magnetic fields occur in the absence of electric fields? That is possible, but not under any circumstances that we are dealing with here.

It is contradicted by observsation, since key elements required by it, which should be observable, are not in fact observed, despite the presence of instruments fully capable of making the observations (i.e., where is the current that powers the sun?). It is also contrary to common sense physics. There has to be an ultimate source of energy for all physical processes, and none is forthcoming in the electric sun theory.

The electrical neutrality of space is not an assumption, it is a direct observation. Why should we "assume" anything that we already know is contrary to observation?

[Moderator note: this thread was created by splitting posts from the ATM thread, The Electric Sun (so you will see some ATM ideas and references).

The posts here are not, primarily, on the ATM idea, the electric Sun, but refer mostly to basic plasma physics, MHD (magneto-hydro dynamics), and the history of its development (especially the role of the contributions of Alfvén).

As there seems to be quite a bit of confusion, among some BAUT members, regarding plasma physics, I think this thread may help to clarify it, as well as provide an opportunity for BAUT members to ask questions about this area of modern physics.]

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There would be a contradiction only if you assume that electrical neutrality requires the complete absence of charged particles. But that is not the case. An electrically neutral plasma is one which has an equal number of positive & negative charge carriers. An electrically neutral plasma in motion will generate a magnetic field (this is an observed fact). The electrical neutrality of space is merely the observation that the number of positive & negative charge carriers is equal, not that they are absent.

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The basic law is "A moving charge creates a magnetic field."
A single charge is/has an electric field.

A time varying magnetic field must cross a wire etc. to create a current flow.
Usually magnetic fields are talked about as being frozen into the plasma depending on the time scale. That means it moves with the plasma.

Plasma(charges, proton, electron, ion) in motion will usually have a driving potential. That would be a current, which is moving charges, which develop a magnetic field. So the magnetic field is a by product of electric field acceleration.

The basic law is "A moving charge creates a magnetic field."

But not all magnetic fields are created by moving charges.

Magnetic fields are created by the spin of the charge and when you align the spins on the electrons in an atom in a material you will produce a magnetic field. Electrons or protons moving in a uniform motion will align the spins, but you can align the electrons without a current, iron is very good at doing it, though other materials will do it as well.

The moral of this is while:

Current = Magnetic Field
Magnetic Field ≠ Current

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Well, I thought it was expected to be a perfect vacuum not so long back, but we move on.

Sure, but it is the role and importance of these plasmas which is now under debate. EUrs, of course, go much further than the mainstream in this respect.

OK

Careful, you almost uttered the words 'frozen in' there! Alfven debunked this idea. He was also the chap who came up with Magnetohydrodynamics BTW, despite you claim in another post that he was very down on the idea!

Sorry, old chap, but frozen in magnetic fields is a direct consequence of Alven's MHD assuming (almost) perfect conductivity. Or did you mean another "frozen in" as I see nowhere that Tim even remotely gets into the neighbourhood of being frozen.

* edited to correct an inaccuracy *

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Optimism does not change the laws of physics. (T'Pol)
A good scientist has freed himself of concepts and keeps his mind open to what is. (Dao De Jing 27)
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Martin ( http://www.geocities.com/DrMartinV )

A moving charge can be considered a current and thus produces a magnetic field. The charge is may move at constant velocity.
A single charge has an electric field around it, but as we are dealing with plasmas here, the single charge electric field does not extend over distances greater than the DeBije length. So, in all, single charge electric fields do not play a large role in the total plasma cloud, apart from creating the plasma frequency which is a collective behaviour of the plasma.

Time varying magnetic fields drive currents, also in a plasma. The fields do not have to cross a wire as the electric charges in the plasma are mobile enough and can set up currents.
Frozen in magnetic fields move with the plasma, indeed. This means that E+vxB=0, but if you look at Ohm's law you will see that there are many more terms than just this one. And uh, ... why are we discussing frozen in fields?

A driving potential is not a current, I can have a potential over empty space and not have a current. I need moving charges to have a current. Plasma in motion is just plasma in motion, e.g. in the sun's convective layer there is a temperature different, which makes the plasma well up in one channel and then down again in another channel, just like air circulation in the Earth's atmosphere.

So, now we get to the crux, it all depends on what scale you look at, just like Tim said above. If you look at the large scale there are the magnetic fields that are moving and changing in time. This time variation drives currents and electric fields via: curl(B) = mu0 J - epsilon0 dE/dt and dB/dt = - curl(E), Maxwell's equations that I hope are out of scrutiny (apart from me making mistakes in wher the mu0 and epsilon0 belong). So even if we have frozen in field, when we compress the plasma, the magnetic changes too via B2 = B1 * surf1 / surf2, where B1 and B2 are the magnetic fluxes through surfaces surf1 and surf2.

If you look at the microscopic physics of how magnetic fields are generated, you need to take another viewpoint, because then you get to the point that somewhere due to random motion of the plasma particles a mini-current is set up and creates a mini-magnetic field. This is a so-called seed field in the dynamo theory for the sun. If things are quiet, the field will contract and dissipate and nothing of it. If things are more turbulent, then we can have that the tiny magnetic loop gets sheared, and folded on itself, basically then doubling the field strength. If you do that often enough you can build up a considerable magnetic field. Naturally (I can see your comment coming, what about the current, you forget about the current) there will be currents that are creating this magnetic field, they will also increase.

So, in summary, I guess you have to be a little schizofrenic if you want to be a plasma(astro)physicist.

__________________
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Optimism does not change the laws of physics. (T'Pol)
A good scientist has freed himself of concepts and keeps his mind open to what is. (Dao De Jing 27)
************************************************** *************************
Martin ( http://www.geocities.com/DrMartinV )

Can we all agree that space is (a) quasi-neutral (b) May contain charge separation regions (wherever there is a double layer)

Regards,
Ian Tresman

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plasma-universe.com

He got pretty damned close to saying it, and that was my concern. And in another thread he made the bizarre claim that Alfven was somehow down on MHD, seemingly unaware that 'he wrote the book on it'! In fact he won his nobel prize for work in this area.

Anyway, this is what Alfven had to say about frozen in magnetic fields:

"The electrical conductivity of any material, including plasma, is determined by two factors: the density of the population of available charge carriers (the ions) in the material, and the mobility of these carriers. In any plasma, the mobility of the ions is extremely high. Electrons and ions can move around very freely in space. But the concentration of ions available to carry charge may not be at all high if the plasma is very low pressure or diffuse. In short, although plasmas are excellent conductors, they are not perfect. It therefore follows that weak electric fields can exist inside them, and magnetic fields are NOT frozen inside them."

So Tim says that space plasmas can be considered charge neutral.
But he also says there may be currents in some regions.
No mention here of magnetic fields, not not even close to "frozen in's" nephew!

__________________
************************************************** *************************
Optimism does not change the laws of physics. (T'Pol)
A good scientist has freed himself of concepts and keeps his mind open to what is. (Dao De Jing 27)
************************************************** *************************
Martin ( http://www.geocities.com/DrMartinV )

I never said any such thing. What I did say, in this post, in this thread was this:
I never suggested that Alfven did not invent magnetohydrodynamics. I have a few of Alfven's books, I have studied MHD, and I have even met Alfven myself. I am well aware of his role in the creation of MHD (although I will also point out that it is unfair to single out Alfven, and not even mention the contributions of people like Parker & Cowling, and others). But what I said was true nevertheless. Alfven did not remain loyal to MHD, but went off on his own. And that's a fact.

Alfven never in his life suggested that magnetic fields were not frozen in, that is a grave misconception held by those who chose to deify Alfven, instead of actually bothering to study the physics that Alfven presented. Whether or not a field is "forzen in" depends entirely on the conductivity of the plasma. The magnetic field is literally frozen in if the plasma is perfectly conducting, which Alfven himself conclusively proved. He also showed that the higher the resistivity of the plasma, the less "forzen in" the field would be.

You miss Alfven's point entirely. He showed that the resistivity of the plasma sets a characteristic time scale for magnetic field drift through the plasma. So, let us say that the drift time scale is 10⁹ years in some plasma. And now let us say that I want to know what's happening in that plasma, in a process that takes 10⁴ years. The time scale I am interested in is very short compared to the drift time scale, so I can safely assume that the magnetic field is forzen into the plasma, over the time scale of my study, with no ill consequences. But, if the drift time scale of that plasma were, say 10³ years, then I would be badly mistaken in assuming that the magnetic field were forzen in, because the drift time scale is short compared to my time scale of interest. Alfven knew all of this, and says so expilicitly in his books & papers. And, as a matter of fact, mainstream plasma astrophysicists today adhere to this rule, as Alfven laid it out. So there is no conflict between the way mainstream scientists treat frozen in magnetic fields, and the way Alfven said they should be treated. There is only a failure of most of Alfven's fans to understand what Alfven actually said.

Alfven's main problem was the tendency in theoretical MHD to assume perfect conductivity, simply because it is a lot easier to compute things. This is still done in studies of "ideal MHD", for the same reason. We learn most efficiently by coming to grips with the "easy" problems first, as they are approximations of the more difficult problems that do not include the approximations of ideal MHD. But most EUers seem to suffer from the misconception that ideal MHD is assumed by mainstreamers to be "real" MHD, so they rail against a ghost of their own invention.

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Have I misunderstood the following:

In 1967 Alfvén [109] noted evidence for the presence of electric fields parallel to magnetic fields, implying that the electric conductivity is not infinite and the magnetic field lines are not “frozen in.” (Later Alfvén [110] recalled that the “frozen field” concept had given him headaches for several years.) In Stephen G. Brush, "Alfvén’s Programme in Solar System Physics" (1992)

Alfvén also published a paper whose abstract states:

The concepts of 'frozen-in magnetic field lines' and 'field-line reconnection', which are frequently used in discussions of the theory of the magnetosphere, have been criticized by Alfven and Falthammar (1971), by Heikkila (1973), and by Alfven (1975). In the present paper, it is demonstrated that both concepts are unnecessary and often misleading. The frozen-in concept is shown to belong to the pseudo-plasma formalism which is useful only in special cases. (From: Alfven, H., "On frozen-in field lines and field-line reconnection" 1967)

Alfvén also wrote:

I thought that the frozen-in concept was very good from a pedagogical point of view, and indeed it became very popular. In reality, however, it was not a good pedagogical concept but a dangerous "pseudopedagogical concept." By "pseudopedagogical" I mean a concept which makes you believe that you understand a phenomenon whereas in reality you have drastically misunderstood it.
[..]
At that time (1950) we already knew enough to understand that a frozen-in treatment of the magnetosphere was absurd. But I did not understand why the frozen-in concept was not applicable.
[..]
In 1963, Fälthammar and I published the second edition
of Cosmical Electrodynamics [12] together. [..] We analyzed the consequences of this in some detail, and demonstrated with a number of examples that in the presence of an E_|| the frozen-in model broke down. On [12, p. 191] we wrote:

"In low density plasmas the concept of frozen-in lines of force is questionable. The concept of frozen-in lines of force may be useful in solar physics where we have to do with high- and medium-density plasmas, but may be grossly misleading if applied to the magnetosphere of the earth. To plasma in interstellar space it should be applied with some care."

[..]
Since then I have stressed in a large number of papers the danger of using the frozen-in concept [..] The most important criticism of the "merging" mechanism of energy transfer is due to Heikkila [40] who, with increasing strength, has demonstrated that it is wrong. In spite of all this, we have witnessed at the same time an enormously voluminous formalism building up based on this obviously erroneous concept. Indeed, we have been burdened with a gigantic pseudoscience which penetrates large parts of cosmic plasma physics. (Alfven, Hannes, "Double layers and circuits in astrophysics" 1986)

Regards,
Ian Tresman

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plasma-universe.com

Yes, you have misunderstood. What Tim said, and what your quotes say is that frozen in is an approximation based on the resistivity and lifetime of the plasma. In the strictest sense, fields are not frozen in since there is always a resistance. However, if the field movement is small during the lifetime of the plasma, you can do an approximation and say it is frozen.

But isn't the crux of Alfven's later work to show that MHD is only applicable in a small minority of cases (the solar interior) and nowhere else?

So, how does mainstream science today incorporate the lessons from Alfven? Any examples where the consequences can be seen?

Cheers.

Tim give a good example of where you would approximate out the change in magnetic fie