Something new under the sun

Zeuzzz said:
No, i think that you need to outline what you think magnetic reconnection is, because from what i've seen so far, you seem to be confused with standard magnetic field topologies and magnetic field lines breaking and reconnecting to each other, ie, "magnetic reconnection".

Just outline what magnetic reconnection is in a few simple sentences, and i'll pick out where the problem is.
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You first (please note that that was my first posting on magnetic reconnection).
 
Hi Tubbythin:

Well I would say that there are some gnomes of some sort, they hold the top layer in place and run the energy to the center of the sun. they also somehow make the elements past iron get from jets in other galaxies to our galaxy.

But where is the temperature on the surface that this would cause, i mean the standrad explanation is a sort of good one, but I bet Zuezz would sling the 'double layer' as something that would keep such a high temperature like 10 million degerees kelvin from showing in the photosphere.
 
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Tubbythin said:
I might be being totally stupid here but... if fusion takes place away from the core, how do we get hydrostatic equilibrium?
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The EU folks have some whacky idea about gravitationally induced electric polarization which supposedly provides a counter-force. They can't put any numbers on this idea, though, because it's nonsense. Just like their other ideas which can "explain" everything but can calculate nothing.
 
Zeuzzz said:
Hows about you just read the publication in the IEEE Journal of Plasma Physics that i keep quoting, and tell me the obvious mistake in their work, as it concludes that magnetic reconnection can not occur, and provides numerous reasons why this is the case.
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That's easy. The article is incredibly obviously wrong throughout its discussion of reconnection:

it does not explicitly reduce
the strength of any part of the magnetic field. Thus, it cannot
liberate magnetic energy that is stored in that field.
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That's like saying "Sawing the legs off the ladder does not explicitly make anything descend. Thus, it cannot liberate gravitational potential energy stored in a can of paint at the top." The energy is released in the wholesale reconfiguration of fields and currents that gets you from T_i to T_f via reconnection configurations, not "explicitly" at any moment in the middle.

Proposing that magnetic field lines move around, break,
merge, reconnect, or recombine is an error based on the false
assumption that the lines are real entities in the first place.
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This is a bald and unsupported assertion, and it is false. Me, sol, and Zig, along with the physics community, "propose that magnetic field lines move around etc." based on correct descriptions of the underlying fields, not based on any assumption that "lines are real entities."

Field lines are not real-world 3-D entities and thus cannot do
anything. Like mathematical singularities, field lines are pure
abstractions and cannot be reified into being real 3-D material
objects.
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Aha, that's the source of the load of baloney is known as "Zeuzzz Mistake 4.1v3". The fact that the fields rearrange themselves as we describe can be concluded from looking at the fields and sources---it's just easier to explain by drawing field lines. Saying "some of the lines in your drawing do not, in reality, exert forces" does not imply, "therefore, the phenomenon you're drawing does not occur", nor does it imply "nothing in this phenomenon exerts forces."

However, a large amount of energy can be stored in and
released from the surrounding field structure but only if either
or both currents I take on lower values.
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"only if ... " is untrue. The author shows that the field energy doesn't change unless you change the currents I, but the author strangely forgets that moving the wires would also change the energy. So what? If you aren't moving the wires or changing the currents, there's no reconnection going on. The author has shown only that nothing happens (neither reconnection nor energy change) in a completely static collection of currents---which has no relevance whatsoever for reconnection, which explicitly involves changing fields (and by implication, changing source currents).

That's what you've been quoting all this time, Zeuzzz? Did you think about it for 30 seconds before devoting your life to it, or did you just count on the Magic of Publication making it infallible? Geez.
 
sol invictus said:
No, Zeuzzz, you simply don't know the meaning of the terms you use. Reconnection is the phenomenon where two points which were not connected by a B field line suddenly become connected, or the other way around. That's why it's called re-connection.
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As far as i can see, reconnection (or cancelling) of metaphysical lines describing the magnitude of an abstract vector field should not result in any release of energy. This is what you described.


Here's a nice animation of it occurring. Note that this is simply the output of a computer simulation of Maxwell's equations in plasma. See how it looks just like the field configuration I plotted? See all that energy being released?

http://www.glue.umd.edu/~drake/movies/reconn_hall.avi
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Cool animation. Where did you get that from?

And what physical property did they assign to the (virtual) magnetic field lines to create this energy? :rolleyes: The usual, plasma is "attatched directly to the field lines" misunderstanding?

Well, considering that all the magnetic field configurations i have been shown so far do indeed change the topology of the magnetic field but none of them have explicitly reduced the strength of any part of the magnetic field itself, it leaves me wondering how any magnetic energy that is stored in that field could be liberated in any way.


The answer to that is quite complex, and probably isn't fully known. I could take a guess based on dimensional analysis, but unless I thought about it more carefully it would remain a guess.
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Indeed, these new real world physical properties of conceptual virtual magnetic field lines are puzzling and complex, yes. :rolleyes:

Infact these magnetic field lines reconnecting are even harder to detect than dark matter, I presume? thats why no-one has come up with a demonstration of actual magnetic reconnection yet.


This is hilarious, still i dont think that anyone understands what has been proposed to happen to magnetic field lines in the *cough* magnetic reconnection process, and still no-one has found any errors in the peer reviewed publication which refutes magnetic reconnection; http://members.cox.net/dascott3/IEEE-TransPlasmaSci-Scott-Aug2007.pdf
 
ben m said:
That's easy. The article is incredibly obviously wrong throughout its discussion of reconnection:



That's like saying "Sawing the legs off the ladder does not explicitly make anything descend. Thus, it cannot liberate gravitational potential energy stored in a can of paint at the top." The energy is released in the wholesale reconfiguration of fields and currents that gets you from T_i to T_f via reconnection configurations, not "explicitly" at any moment in the middle.



This is a bald and unsupported assertion, and it is false. Me, sol, and Zig, along with the physics community, "propose that magnetic field lines move around etc." based on correct descriptions of the underlying fields, not based on any assumption that "lines are real entities."



Aha, that's the source of the load of baloney is known as "Zeuzzz Mistake 4.1v3". The fact that the fields rearrange themselves as we describe can be concluded from looking at the fields and sources---it's just easier to explain by drawing field lines. Saying "some of the lines in your drawing do not, in reality, exert forces" does not imply, "therefore, the phenomenon you're drawing does not occur", nor does it imply "nothing in this phenomenon exerts forces."



"only if ... " is untrue. The author shows that the field energy doesn't change unless you change the currents I, but the author strangely forgets that moving the wires would also change the energy. So what? If you aren't moving the wires or changing the currents, there's no reconnection going on. The author has shown only that nothing happens (neither reconnection nor energy change) in a completely static collection of currents---which has no relevance whatsoever for reconnection, which explicitly involves changing fields (and by implication, changing source currents).

That's what you've been quoting all this time, Zeuzzz? Did you think about it for 30 seconds before devoting your life to it, or did you just count on the Magic of Publication making it infallible? Geez.
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This is a good one. I'm presuming that your joking on all of these completely illogical assertions?

Well, I certainly hope you are, for your sake. :D

(If not, choose one of those statements, and i'll be happy to discuss its veracity in detail tomorrow)
 
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Reality Check said:
I think that Zuezzz's position on magnetic reconnection is largely formed by the following paragraphs in the paper that he quotes

Figure 1 is the similar to the diagrams previously posted here with 1, 2, 3 and 4 labeling the magnetic field curves in the 4 quadrants.​

I am fairly sure that magnetic field lines move when the magnetic field changes.​
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:D

Yeah, because the fact that abstract lines 'move' really proves that magnetic reconnection releases large amounts of energy :rolleyes:
 
Reality Check said:
I was under the impression that magnetic field lines in light moved. Am I wrong?
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Reality check, i haven't got time for more of your ignorant comments, so just post your daily dose of pseudoskeptisism towards me and I'll debunk it thouroughly tomorrow.

READ MY PREVIOUS POSTS. ESPECIALLY THE ONES WHERE I CONTINUALLY EXPLAIN WHAT A MAGNETIC FIELD LINE IS, AND WHAT IT IS PHYSICALLY CAPABLE OF DOING, (ie, nothing physical)
 
Energy of a magnetic field:

u = 1/(2 mu0) Integral (B^2 dV )

Changing the fields (and remember, reconnection describes a set of changing fields) can change this integral.
 
This movie of a simulation shows quite clearly how reconnection happens, and you can see for yourself the mechanism by which so much energy is released:

http://www.glue.umd.edu/~drake/movies/reconn_hall.avi

This paper is also noteworthy:

http://www.glue.umd.edu/~drake/publications/reconnection/birn01.pdf

It describes the results of a bunch of different simulations of reconnection performed by various groups using different numerical techniques. They are all in qualitative agreement (with the exception of conventional MHD with regard to the rate, and the reason for that is now understood).

The only mystery surrounding reconnection was the rate at which it occurs. Observations show it happens much faster than the old theoretical (Sweet-Parker) model predicted. It sounds like the origin of that discrepancy is now pretty well understood, and theory agrees pretty well with observation and simulations.
 
Ziggurat said:
The EU folks have some whacky idea about gravitationally induced electric polarization which supposedly provides a counter-force. They can't put any numbers on this idea, though, because it's nonsense. Just like their other ideas which can "explain" everything but can calculate nothing.
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Well, I would certainly prefer a model that explains everything but can calculate nothing, to a model that can calcuate everything and explain nothing.

If you can calcuclate everything, but explain nothing physical from them, then why do the calculations at all? :D
 
Zeuzzz said:
As far as i can see, reconnection (or cancelling) of metaphysical lines describing the magnitude of an abstract vector field should not result in any release of energy.
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Translation: I was totally wrong but am too stubborn to admit it. I am now shifting the goal posts madly, trying to make it sound as though the only objection I ever had was to the statement that lots of energy is released.

Cool animation. Where did you get that from?
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http://www.glue.umd.edu/~drake/

This is a simulation of Maxwell's equations in plasma. It shows reconnection occurring and lots of energy being released. What do you think of that?

And what physical property did they assign to the (virtual) magnetic field lines to create this energy? :rolleyes: The usual, plasma is "attatched directly to the field lines" misunderstanding?
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They didn't assign any property to the lines - they just drew them to guide the eye after numerically solving Maxwell's equations. Have you already forgotten that you agreed that, given a field, one can unambiguously draw the field lines?

Well, considering that all the magnetic field configurations i have been shown so far do indeed change the topology of the magnetic field but none of them have explicitly reduced the strength of any part of the magnetic field itself, it leaves me wondering how any magnetic energy that is stored in that field could be liberated in any way.
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You're wondering that because you don't understand E&M. It's quite obvious why it happens, and I've already explained it. Furthermore, given a numerical solution such as the one in the simulation, one can simply check to see what happens to the energy in the field as reconnection is occurring. The answer is that a lot gets released.

This is hilarious,
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Indeed.

and still no-one has found any errors in the peer reviewed publication which refutes magnetic reconnection; http://members.cox.net/dascott3/IEEE-TransPlasmaSci-Scott-Aug2007.pdf
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Ah, total denial of reality. Yes, no one has found any errors if you ignore all the posters that found basic and fundamental errors in it.
 
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Zeuzzz said:
Well, I would certainly prefer a model that explains everything but can calculate nothing, to a model that can calcuate everything and explain nothing.

If you can calcuclate everything, but explain nothing physical from them, then why do the calculations at all? :D
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Except the current models we use explain a hell of a lot. So its rather a moot argument.
 
Zeuzzz said:
Reality check, i haven't got time for more of your ignorant comments, so just post your daily dose of pseudoskeptisism towards me and I'll debunk it thouroughly tomorrow.

READ MY PREVIOUS POSTS. ESPECIALLY THE ONES WHERE I CONTINUALLY EXPLAIN WHAT A MAGNETIC FIELD LINE IS, AND WHAT IT IS PHYSICALLY CAPABLE OF DOING, (ie, nothing physical)
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So you think that I am right and the paper is wrong when it states that magnetic field lines do not move.

I know what a magnetic field line is. It is a depiction of the magnetic vector field. When the magnetic vector field changes the depiction of the vector field changes and so the magnetic field lines move.
 
As far as i can see, reconnection (or cancelling) of metaphysical lines describing the magnitude of an abstract vector field should not result in any release of energy.
sol invictus said:
Translation: I was totally wrong but am too stubborn to admit it. I am now shifting the goal posts madly, trying to make it sound as though the only objection I ever had was to the statement that lots of energy is released.
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Not at all Sol, this is the crux of the issue here. You are claiming that the field that you showed exhibits magnetic reconnection, when it doesn't. It shows a neutral point where the vectors in question cancel, and the lines showing these vectors are brought towards each other. This does not change the fact that although the proposed reconnection mechanism changes the topology of the magnetic field, it does not explicitly reduce the strength of any part of the magnetic field. Thus, it cannot liberate magnetic energy that is stored in that field. Field lines themselves can not release any phsycial energy at all. By definition, magnetic reconnection is the release of energy from the lines of the field reconnecting, from the wikipedia page;

field lines enter the separator from two of the domains, and are spliced one to the other,
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Well, I still dont know what 'spliced' means, and i still dont know what the equations are for the splicing energy released by two metaphysical lines. :eye-poppi

Magnetic reconnection is the process whereby magnetic field lines from different magnetic domains are spliced to one another,
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They didn't assign any property to the lines - they just drew them to guide the eye after numerically solving Maxwell's equations. Have you already forgotten that you agreed that, given a field, one can unambiguously draw the field lines?
Click to expand...


Ok, so if they didn't assign any property to the lines, what is creating the energy?



You're wondering that because you don't understand E&M. It's quite obvious why it happens, and I've already explained it.
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Oh yeah, your 'tangles' theory. Got any numbers yet?
 
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ben m said:
Energy of a magnetic field:

u = 1/(2 mu0) Integral (B^2 dV )

Changing the fields (and remember, reconnection describes a set of changing fields) can change this integral.
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Oh you and your funny abstractions, next thing you know, you will say that gravity is real.
;)

I think that Zeuzzz has made the usual (in reverse) finger/moon sort of argument, the fact that the arc the finger traces accuratly predicts the behavior of the moon, will still not be the moon.
No matter how accurate the model is at predicting the behavior of reality, he will say it is just a model and ignore the accuracy of predictions.

Not that he has offered anything of his own in this regard, you can say that the lines represent the gradients of a field in three dimensional space and predict the behavior of a particle to any degree of accuracy you choose. He will deny that the model has meaning. But the application of the fields and reconnection in machines will continue to work.
 
Zeuzzz said:
Well, I would certainly prefer a model that explains everything but can calculate nothing, to a model that can calcuate everything and explain nothing.

If you can calcuclate everything, but explain nothing physical from them, then why do the calculations at all? :D
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Be sure to sign your name to all the bridges you build, I don't want to drive over them!

You just fire from the hip don't you, I don't suppose that if people come out with all sorts of physical demonstrations that it will matter to you.

Blind faith that you are always right is a sure sign of a lack of critical thought. You are engaging in cynicism not scepticism, that is why you just refuse to actually discuss the models and why they are wrong. You are making grand philospohical statements that have no bearing on the physical world either, the fact that the models you say are abstraction doesn't mean that they don't make accurate predictions.

You have yet to explain anything either. Your lack of math and formal description to counter the statements modeled by others is rather telling. You just wave your hands and foam a little, that is not critical thought in the least. that is philospohy.

So why not admit your reason is as follows: you don't like it. Try a physical critique of the model then, see if you can come up with something concrete and not philosophical to counter the model. You have yet to present physical evidence that can not be explained by the model, not have you offered a better model, thus you are a cynic.


So please stop the posturing and present you data, numbers and events that demonstrate that what the model being presented is, is false.

Can you, will you? Or are you all thunder and no substance? (And please spare us the argumentation by spam (ala BAC), present a clear, concise and formal critique of the model you don't like.)
 
Dancing David said:
But the application of the fields and reconnection in machines will continue to work.
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What machines?

Did you find the data of this splicing reaction between two lines that seems to have illuded everyone else?

If you did, post it here.
 
Zeuzzz said:
Well, I would certainly prefer a model that explains everything but can calculate nothing, to a model that can calcuate everything and explain nothing.

If you can calcuclate everything, but explain nothing physical from them, then why do the calculations at all? :D
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I see your confusion extends beyond the particular field of science under discussion to the very nature of science itself.

The entire point of science is not simply to explain. Mythology works fine if all you want is an explanation. The point of science is to predict. And calculations (as opposed to explanations) give you the most precise predictions that we can make.
 
Dancing David said:
Well, I would certainly prefer a model that explains everything but can calculate nothing, to a model that can calcuate everything and explain nothing.

If you can calcuclate everything, but explain nothing physical from them, then why do the calculations at all?
Click to expand...

Be sure to sign your name to all the bridges you build, I don't want to drive over them!

You just fire from the hip don't you, I don't suppose that if people come out with all sorts of physical demonstrations that it will matter to you.

Blind faith that you are always right is a sure sign of a lack of critical thought. You are engaging in cynicism not scepticism, that is why you just refuse to actually discuss the models and why they are wrong. You are making grand philospohical statements that have no bearing on the physical world either, the fact that the models you say are abstraction doesn't mean that they don't make accurate predictions.

You have yet to explain anything either. Your lack of math and formal description to counter the statements modeled by others is rather telling. You just wave your hands and foam a little, that is not critical thought in the least. that is philospohy.

So why not admit your reason is as follows: you don't like it. Try a physical critique of the model then, see if you can come up with something concrete and not philosophical to counter the model. You have yet to present physical evidence that can not be explained by the model, not have you offered a better model, thus you are a cynic.


So please stop the posturing and present you data, numbers and events that demonstrate that what the model being presented is, is false.

Can you, will you? Or are you all thunder and no substance? (And please spare us the argumentation by spam (ala BAC), present a clear, concise and formal critique of the model you don't like.)
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That was the only slightly philosophical statement i made all day. And it was just an observation that the opposite situation of what he described would be equally bad, you have to have a mixture of both. Not even relevant to this topic. The other statements i made are all facts. Feel free to quote me on one if you will.
 
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Zeuzzz said:
What machines?

Did you find the data of this splicing reaction between two lines that seems to have illuded everyone else?

If you did, post it here.
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DD is probably referring to the 3 machines in the previous links, i.e. the Versatile Toroidal Facility, the Magnetic Reconnection Experiment and the Swarthmore Spheromak Experiment .

N.B. each site has a list of publications that you may want to look at. They should have "the data of this splicing reaction between two lines that seems to have illuded everyone else".

P.S. This is a random paper from the sites: Study of driven magnetic reconnection in a laboratory plasma
 
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Zeuzzz said:
That was the only slightly philosophical statement i made all day. And it was just an observation that the opposite situation of what he described would be equally bad, you have to have a mixture of both. Not even relevant to this topic. The other statements i made are all facts. Feel free to quote me on one if you will.
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Unfortunately for you, your model of surface fusion calculates nothing and explains nothing. Without core fusion there is nothing to balance gravity and therefore no hydrostatic equilibrium. The star would just collapse until something stopped it like, oh, I dunno, fusion in the core.
 
Reality Check said:
P.S. This is a random paper from the sites: Study of driven magnetic reconnection in a laboratory plasma
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II. PHYSICS ISSUES OF MAGNETIC RECONNECTION
To describe the motion of magnetic field lines in a
plasma, Eq. ~1!, for the evolution of the magnetic field B, can
be derived by combining Maxwell equations and Ohm’s law
]B
] t
5“3~v3B!1
h
m0
¹2B. ~1!
The first term on the right-hand side represents motion of
field lines frozen-in to the plasma.1
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Not looking good so far, they are using the plasma as a perfect conductor for a start. Which it isn't. I'll have a look at the rest tomorrow.
 
Zeuzzz said:
Not looking good so far, they are using the plasma as a perfect conductor for a start. Which it isn't. I'll have a look at the rest tomorrow.
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Forget about the theory - look at the experimental results actually measuring magnetic reconnection. Figure 7a should look familiar to you.
 
Zeuzzz said:
Not looking good so far, they are using the plasma as a perfect conductor for a start. Which it isn't. I'll have a look at the rest tomorrow.
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Don't look too hard Zeuzzz, you might find yourself back at http://www.glue.umd.edu/~drake/ , the source of the Maxwell-based animation you're carefully ignoring, where the plasmas aren't perfect conductors. Then you'd have to ignore that, too.
 
Tubbythin said:
Unfortunately for you, your model of surface fusion calculates nothing and explains nothing. Without core fusion there is nothing to balance gravity and therefore no hydrostatic equilibrium. The star would just collapse until something stopped it like, oh, I dunno, fusion in the core.
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The EU response is probably on the lines of "it is electricity providing the hydrostatic equilibrium".:D

Another thing their "model" has to explain is why the flux of neutrinos that has been detected from the sun matches the predictions of the fusion model. Another EUist (BeAChooser) has already admitted elsewhere "I'm convinced that the sun might be mostly nuclear powered" but he will probably say that "might" and "mostly" does not rule out an electric sun.
 
Zeuzzz said:
Not at all Sol, this is the crux of the issue here. You are claiming that the field that you showed exhibits magnetic reconnection, when it doesn't.
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Yes, it does. By definition.

By definition, magnetic reconnection is the release of energy from the lines of the field reconnecting, from the wikipedia page;
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"field lines enter the separator from two of the domains, and are spliced one to the other,"

That is precisely what happens in the field configuration Zig and I gave. By your own definition, that field configuration reconnects.

Well, I still dont know what 'spliced' means, and i still dont know what the equations are for the splicing energy released by two metaphysical lines. :eye-poppi
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Look "splice" up in the dictionary. It's what happens at x=y=0 in the field configuration I gave, as you vary a and b.

As for the energy, that's in general changing as you vary a and b. The energy density for that field is proportional to a^2 x^2 + b^2 y^2, so it's a function of a and b.

Ok, so if they didn't assign any property to the lines, what is creating the energy?
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The changing magnetic field.

Again: they solved Maxwell's equations. The solution tells them how much energy is released, as well as everything else they might want to know.

Then they plotted the solution and drew the field lines. They didn't "assign any property" to the lines - they just plotted them.

Which part of that do you fail to understand?
 
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Reality Check said:
The EU response is probably on the lines of "it is electricity providing the hydrostatic equilibrium".:D
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Except if it was near the surface where fusion was taking place then a reasonable proportion of photons emitted would arrive at Earth without undergoing multiple scatterings. We'd then see peaks in the Sun's spectrum corresponding to the energy released in the various fusion processes (way up in the gamma-ray region). Its only because of the random walk that photons do on their way out from the centre that the Sun has a pretty good black-body distribution.
 
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Zeuzzz said:
Not looking good so far, they are using the plasma as a perfect conductor for a start. Which it isn't. I'll have a look at the rest tomorrow.
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They are explicitly NOT doing that:
"The second term describes diffusion of magnetic fields with the diffusion coefficient proportional to the plasma resistivity."
In other words, the fact that they aren't dropping the second term means explicitly that they are NOT treating the plasma as a perfect conductor. Which you should have realized from the part you quote where they mention Ohm's law - you know, that little equation having to do with currents and resistance. Which in turn is something that perfect conductors don't have. You keep stumbling over the glaringly obvious.
 
Zeuzzz said:
As far as i can see, reconnection (or cancelling) of metaphysical lines describing the magnitude of an abstract vector field should not result in any release of energy. This is what you described.
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So, now you're confusing reality with the model of reality and using the fact that the model is not reality in order to bash the model ?

This is a good one. I'm presuming that your joking on all of these completely illogical assertions?

Well, I certainly hope you are, for your sake.
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"Damn, can't answer those points. Better sound clever, now."
 
Ziggurat said:
I see your confusion extends beyond the particular field of science under discussion to the very nature of science itself.

The entire point of science is not simply to explain. Mythology works fine if all you want is an explanation. The point of science is to predict. And calculations (as opposed to explanations) give you the most precise predictions that we can make.
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Bravo, Zig. Pnwed.
 
Classical vs contemporary physics

Way back when the underlying cause(s) of electricity and magnetism were not known. Fast forward a century or two and today we know about electrons, ions, electron spins, orbitals, etc, etc, etc.

If you look at plasma processes in terms of what the electrons and ions (and neutral atoms/molecules too) are doing, how does a magnetic field arise (excluding externally imposed fields)? Given that moving charges create such fields, does the existence of such magnetic fields - in the solar wind say, or the Sun - automatically mean that there are currents (in terms of contemporary physics)?

Is there a quantum mechanics version of Maxwell's equations?

I'm quite interested in all folk who've been actively participating in this thread recently to reply to the these questions; I'm particularly interested to hear from iantresman, Zeuzzz, and BeAChooser on the extent to which you think Alfvén, Birkeland, Peratt, Scott, Thornhill, et al. modified/extended plasma physics (a branch of classical physics) to incorporate the reality of the actual charge carriers (electrons and ions).
 
DeiRenDopa said:
I'm quite interested in all folk who've been actively participating in this thread recently to reply to the these questions; I'm particularly interested to hear from iantresman, Zeuzzz, and BeAChooser on the extent to which you think Alfvén, Birkeland, Peratt, Scott, Thornhill, et al. modified/extended plasma physics (a branch of classical physics) to incorporate the reality of the actual charge carriers (electrons and ions).
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.
You've hit the nail on the head. Alfvén notes:

.. we can describe electromagnetic phenomena in space either in terms of a magnetic field B or in terms of electric currents i. As magnetic fields are easy to measure, and, moreover, the mathematical treatment becomes simpler if i is eliminated, it seems obvious that we should use the field description and eliminate i. For example, when we treat waves propagating through a plasma, they are certainly associated with electric currents, but in many cases we can regard a current implicitly as the curl of the magnetic field and ignore it. However, in doing so we lose the particle aspect of the current; in other words, we neglect the fact that an electric current in space consists of motion of charged particles which have a certain mass, charge, and velocity, and which can often be considered as constituents of a gas with a certain temperature. -- Hannes Alfvén, Cosmic Plasma, (1981) "Electric Currents in Space Plasmas"​
 
DeiRenDopa said:
Is there a quantum mechanics version of Maxwell's equations?
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Yes. It's called quantum electrodynamics, or QED for short.

You should distinguish between the fact that the charge carriers are individual particles - which is perfectly possible to model using classical E&M - and truly quantum effects.

True quantum corrections to classical E&M are usually not important when you're interested in something macroscopic. In the case of plasmas, there are examples where QM matters (e.g. fusion) but for most phenomena the classical description is perfectly good. Particle effects can be quite significant in some regimes (very low density, for example), but again can be ignored much of the time.
 
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DeiRenDopa said:
Given that moving charges create such fields, does the existence of such magnetic fields - in the solar wind say, or the Sun - automatically mean that there are currents (in terms of contemporary physics)?
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Yep, the fields are generated by electric currents, which can be generated by various dynamo processes (complicated) and self-sustained by standard inductance in a highly conductive medium.

Is there a quantum mechanics version of Maxwell's equations?
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Quantum electrodynamics is a complete quantum theory of electromagnetism; it's been referred to as the most-precisely-tested theory in the history of science. If you want something easier, Schrodinger's Equation can be written in a semiclassical way (quantum particles interacting with classical fields). In either case, you don't expect any particularly quantum behavior in space plasmas; the de Broglie wavelengths of all particles are much smaller than most relevant distance scales.
 
Thanks iantresman, sol invictus, and ben m, for responding so quickly! :)

It'd be great to hear from Belz..., Dancing David, Reality Check, Zeuzzz, and Ziggurat too (as well as, going back earlier, BeAChooser, and MattusMaximus).

sol invictus and and ben m: do you think Alfvén, in the bit iantresman quoted, is right about the equivalence of treatment (B vs i), and the possible loss of some important aspects by using B instead of i?

iantresman: what about Birkeland, Bruce, Carlqvist, Fälthammar, Juergens, Langmuir, Peratt, Scott, Talbott, Thornhill and all the others cited on your webpage or introduced by Zeuzzz: to what extent does their work acknowledge the sorts of things sol invictus and and ben m pointed out (for example, that reality is QED, but that quantum and particle effects can be ignored for most plasmas that space scientists and astrophysicists study)?
 
DeiRenDopa said:
Way back when the underlying cause(s) of electricity and magnetism were not known. Fast forward a century or two and today we know about electrons, ions, electron spins, orbitals, etc, etc, etc.

If you look at plasma processes in terms of what the electrons and ions (and neutral atoms/molecules too) are doing, how does a magnetic field arise (excluding externally imposed fields)? Given that moving charges create such fields, does the existence of such magnetic fields - in the solar wind say, or the Sun - automatically mean that there are currents (in terms of contemporary physics)?
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I would have to take a back seat on this one, I would want to make sure that what I said was careful. So yes there woukld be currents, but the conditions and states of those currents would vary widely from situation to situation.
Is there a quantum mechanics version of Maxwell's equations?
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I am a puppy here, whatever the big dogs say...
I'm quite interested in all folk who've been actively participating in this thread recently to reply to the these questions; I'm particularly interested to hear from iantresman, Zeuzzz, and BeAChooser on the extent to which you think Alfvén, Birkeland, Peratt, Scott, Thornhill, et al. modified/extended plasma physics (a branch of classical physics) to incorporate the reality of the actual charge carriers (electrons and ions).
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DeiRenDopa said:
If you look at plasma processes in terms of what the electrons and ions (and neutral atoms/molecules too) are doing, how does a magnetic field arise (excluding externally imposed fields)? Given that moving charges create such fields, does the existence of such magnetic fields - in the solar wind say, or the Sun - automatically mean that there are currents (in terms of contemporary physics)?
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There are two possible sources for magnetism in matter: the center-of-mass motion of charge carriers (aka currents) and the spin of charged particles (mostly electrons, which have much larger magnetic spin moments than protons). Electron spin rather than current is what produces ferromagnetism, for example.

The electron spins in plasmas should not, in general, be very significant. Thermal energies will tend to prevent significant polarization with the local magnetic field (low susceptibility). On a larger scale, dipole-dipole interactions will work to demagnetize a plasma, which means that the polarization of spins in a plasma cannot be self-sustaining even if the susceptibility is high.

So in short, yes, if you've got a magnetic field in a plasma, you've got currents.
 
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