dafydd
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Perhaps he is a New Waver or a New Romantic and is feeling nostalgic.
Problems With Magnetic Reconnection
- Thread starter michaelsuede
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Perhaps he is a New Waver or a New Romantic and is feeling nostalgic.
Michael Mozina
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FYI, I've never really had any issue with your comments, or your position to be quite honest. The only thing I find "frustrating" about your position is your refusal to "meet me in the middle" and accept that the circuit orientation is equally viable, equally well suited to describe events in plasma, and equally capable of being applied to all these same topics. Instead of meeting me in the middle, you're dragging your feet, kicking and screaming and ignoring the logic entirely. Maxwell's equations are all about the relationship between E and B and they are interchangeable in math formulas.
And when you get back, please tell us what you've learned. I really would be curious to know.
GeeMack
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I commented on it more than once, but for the record, on March 2nd, 2010, over a year ago in this post. On March 29, 2011, tusenfem commented on it in this post, and on April 1, 2011, in this post. Tubbythin made a comment on it on April 5, 2011 in this post. And Reality Check commented on it today, April 7, 2011, in this post. That's just the quickie list. Tim Thompson has commented on it several times. I seem to recall at least sol invictus, W.D.Clinger, ben m, DeiRenDopa, and Ziggurat commenting on the paper's lack of support or its irrelevance to the claim that there are problems with magnetic reconnection.
Go ahead.
So there are experts here in plasma physics and/or astrophysics who have read and commented on the Alfvén book. And there are several posters here, including some experts in plasma physics and/or astrophysics, who have read and commented on the Onel and Mann paper. The consensus seems to be that support for the claim about problems with magnetic reconnection is either nonexistent and/or has been superseded by more contemporary, more thorough, and more rigorous research.
Yes?
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Marcus
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Quick question, I don't have time to read the whole thread right now (this quote is from the second page)-
Did he ever provide the basic math requested?
If not, which excuse won out:
a) math is irrelevant
b) I won't be forced to bark math on command
Michael Mozina
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Ditto on how I feel about you. You haven't even read Alfven's work or at least not commented on it, so you have nothing to bitch about.
This is your strawman. I simply asked you a simple question. I don't happen to know the names of every single Nobel Prize winning author on every topic under the sun. I'd simply not heard his name before. I never claimed his work was unimportant or unworthy of my time. That's you pathetic little personal attack strawman.
Thanks. That was actually useful information.
I said nothing at all about either book or author being more or less important than any other book. Again, this is your own strawman. I simply asked a very innocent question. Notice how you all have this emotional need to 'attack the individual' rather than to deal with the materials present. How about YOU COMMENT ON MANN"S paper for us?
OMG! I was busy working, so I simply asked! Holy cow. Next time I'll just fire up a search engine and save myself the personal attack BS.
Well ignorance perhaps, but hypocrisy no. You seem to have completely ignored the fact that I accept the B oriented approach, I simply think you folks gave it a HORRIFIC name. You short circuit a couple of current carrying plasma filaments through a double layer and claim "magnetic reconnection did it". Alfven's method of double layer events is just as valid as yours orientation. That's the part you folks refuse to accept. Since I have already moved to a 'middle position", the only one of us that could possibly be called a hypocrite is you, not me. You refuse to accept Alfven's circuit explanations for the very same flare and magnetospheric events where you apply 'magnetic reconnection' theory, whereas I simply see them as flip sides of the same coin, just a B vs. E orientation. I simply think that you gave an *ELECTRICALLY ACTIVE* process a very *STUPID* title.
You're the one who won't even be bothered to read or comment on the circuit oriented material, yet you refuse to accept Alfven's circuit oriented approach to these very same events in space! Don't even *THINK* about lecturing me about hypocrisy until you've either read and commented on the flaw you found in Alfven's approach, or you accept his approach as being equally valid to any B oriented approach to DISCHARGE processes in plasma.
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Michael Mozina
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You mean you personally handwaved at their work with a single sentence over a year ago, and you've never done anything OTHER than handwave at any of the papers I have presented.
tusenfem and Tim are fully capable of speaking for themselves and they've already earned my respect, unlike you.
Ya, but you aren't one of them.
Ya, but again you aren't one of them.
You can't "supersede" the E oriented approach to plasma physics. It's always going to be inseparably linked to the B orientation via Maxwell's equations. If and when ANY of you ACCEPT THAT REALITY, you'll find me already positioned right in the middle. I've never rejected your math, just the absolutely *RIDICULOUS* name you gave a CURRENT CARRYING ENERGY EXCHANGE IN PLASMA.
Do you EVER intend to read or comment on any of Alfven's work. I've never seen you personally cite any flaw in his work on plasma physics, in fact I've never heard ANYONE cite a specific flaw in his work on MHD theory and plasma physics in general. About all I've ever seen is a lot of handwaving from you personally.
Michael Mozina
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Yes, I provided a host of papers from Onel and Mann the explain the same kinds of flare events from the circuit oriented approach. Nobody has actually denied the validity of that work. Alfven wrote about magnetospheric processes that can be explained by a 'circuit' oriented approach, and again, I've never seen anyone find a flaw in that work either. I've provide math by experts. What they seem to want is for me to personally post math so they can *THEN* look for a flaw so that they can hope to ridicule the individual rather than to focus on the topic. They don't actually care about the math. They ignore it when it suits them.
Michael Mozina
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It may not have been the first time, but I had either missed that statement (God forbid) or forgotten. I don't profess to be perfect. I'm man enough to admit my mistakes too. I bash the TOPICs, whereas usually you folks fixate on the individual in my experience. I should never have attacked Tim like that to start with, so I technically wronged him twice, and I frankly think I got what I deserved.
I guess I personally need to fixate on ONLY THIS topic lest my posts disappear, and in this case you're dead wrong. I've already admitted that your mathematical presentation are fine. I've simply complained about the absolutely ATROCIOUS title you slapped to a "current carrying' process.
You're the one's trying to claim Alfven's circuit oriented approach isn't just as valid, but Maxwell's equations prove conclusively that you are dead wrong.
In terms of the other "issues" I have with mainstream beliefs, I'll save my breath for the appropriate thread(s).
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GeeMack
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Michael Mozina
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No, that's just your repeated claim that is without merit. You can add circuits and resistors at the appropriate places in a circuit oriented approach! The loops don't HAVE to be treated as singular things at the point of intersection. You could choose to add resistors and such to the appropriate places, show a change over time of the circuit topology and call it 'circuit reconection" any time you wish. Instead you see a change in magnetic field topology, ignore the currents that sustain them, and call it 'magnetic reconnection" even though no individual magnetic lines ever actually disconnected from or reconnected to any other actual magnetic lines!
The primary requirement is that no current could be flowing through the point in question, which pretty much rules out your whole approach and it also explains why he outright rejected the whole MR concept, along with the fact that individualized magnetic lines are physically incapable of disconnecting or reconnecting to other individual lines. You aren't just changing a magnetic field topology, your changing the circuit topology as well. How you choose to label that 'reconnection' event seems somewhat arbitrary at first glance. On the other hand circuit theory is consistent with electrical engineering and particle physics theory.
I don't doubt for a moment that the double layer that forms between the two circuits will be "explosive" and short lived.
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W.D.Clinger
Philosopher
You haven't been paying attention. Weinberg's Cosmology is one of the best available books on modern cosmology, a subject in which you feign considerable interest.
You have replied to posts that practically begged you to pay attention to Steven Weinberg or to his books. Here's an example:
If you don't read my posts before replying to them, the fault is yours.W.D.Clinger said:
Shouting in capitals isn't emotional?
I looked at that paper a long time ago, and had nothing to add to tusenfem's expert analysis of it at that time, which he repeated in this thread on 29 March 2011:
You, however, have refused to provide "the E orientation of magnetic reconnection". That was your claim. Instead of railing at me for having nothing to say about an irrelevant paper, you should meet tusenfem's challenge and support your claim.tusenfem said:
That would be appreciated. Checking basic facts before you post is better than expressing outrage over the criticism you deserve for posting nonsense.
Wow.
- You accept the "B oriented approach", but have some kind of semantic objection to its name.
- You favor an "E oriented approach", but ignore all requests to explain it. (See tusenfem's post above.)
- You misrepresent what everyone is saying about magnetic reconnection, while accusing us of attacking straw men.
- You pretend to expertise in circuit theory, after demonstrating profound inability to draw or even to read a circuit.
- You regard your interpretation of Alfvén's keynote remarks as definitive, even after qualified people have told you many times that Alfvén was attacking misuses of an MHD approximation he himself had popularized.
- You repeat your hypocritical demand that we pay more attention to your holy texts than you pay to modern science.
Reality Check
Penultimate Amazing
tusenfem stated the circuit theory is equally viable to MHD. It is equally capable of being applied to all these same topics.
It is not (and this is where you go wrong) "equally well suited to describe events in plasma".
There is no "meeting in the middle". Science does change just because of a wish to be polite to people and accept their erroneous ideas.
Circuit theory can never describe the details of plasma, magnetic fields, electric fields, densities, Alfven waves etc.
MHD can describe details of plasma, magnetic fields, electric fields, densities, Alfven waves, etc.
Circuit theory is an evern greater approximation than the various approximations that are done for MHD.
michaelsuede
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None of the MHD models are capable of describing a double layer condition.
It can not be done using a fluid theory.
Adding in ad hoc resistivity in order to make your model meet with observation does not explain why the plasma should react in a manner similar to a double layer and exhibit resistivity.
This is called reification of a model.
If your models actually did explain all observations of "reconnection," then there would be no unresolved reconnection problems. Your models would predict and explain what is occurring.
You will never be able to predict and explain all "reconnection" events using fluid models.
Ever.
Which I assume is the entire point of using fluid models.
PIC can describe it accurately, but of course the results from the PICs are twisted around on themselves since the entire point of using PICs is to help derive a fluid model. Of the PICs that do use realistic conditions, they all ultimately portray the formation of double layers. Why this continues to be ignored is beyond me.
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Reality Check
Penultimate Amazing
michaelsuede: Why are no DLs detected in MR experiments until after reconnection
You do not have to keep repeating the obvious.
So what?
Double layers are are an effect of magnetic reconnection, not a cause.
You are still ignoring Lessons from Labatory Experiments on Reconnection, R.L. Stenzel, W. Gekelman and J. M. Urrutia 1986
which clearly shows (read the abstract, see Fig 9) that current disruption (and thus DLs) happens afer the magnetic reconnection.
michaelsuede,
Why are no DLs detected in MR experiments until after reconnection?
Or to put it another way: Where are your citations to the formation of DLs in magnetic reconnection experiments before or at the reconnection event?
None of the MHD models are supposed to be capable of describing a double layer condition.
You do not have to keep repeating the obvious.
So what?
Double layers are are an effect of magnetic reconnection, not a cause.
You are still ignoring Lessons from Labatory Experiments on Reconnection, R.L. Stenzel, W. Gekelman and J. M. Urrutia 1986
which clearly shows (read the abstract, see Fig 9) that current disruption (and thus DLs) happens afer the magnetic reconnection.
michaelsuede,
Why are no DLs detected in MR experiments until after reconnection?
Or to put it another way: Where are your citations to the formation of DLs in magnetic reconnection experiments before or at the reconnection event?
Tim Thompson
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Alfven's Faulty Boundary Conditions
Fair enough. So we can agree that (a) I have indeed read Alfven's Cosmic Plasma and that (b) I did not say that the circuit paradigm was false or invalid or the functional equivalent thereof. So, moving right along ...
I already did, on 5 April 2011 ...
And on 4 February 2010, quoted again on 5 April 2011
These arguments constitute a proper & detailed demonstration of that specific claim. Deal with them, or don't, but if you don't, then there is nothing more to say on this point.
As for the Onel & Mann paper (Generation of Large Scale Electric Fields in Coronal Flare Circuits, Central European Astrophysical Bulletin 33: 141-154, 2009), I will address it specifically in a later post. However, be aware of the point I am making here as regards Alfven: "Alfven established faulty boundary conditions because he was guided by a faulty paradigm, ... ". Nowhere in the Onel & Mann paper will you find any mention of Alfven's boundary conditions. Therefore the Onel & Mann paper is not relevant specifically to my claim that Alfven's boundary conditions are faulty.
Fair enough. So we can agree that (a) I have indeed read Alfven's Cosmic Plasma and that (b) I did not say that the circuit paradigm was false or invalid or the functional equivalent thereof. So, moving right along ...
I already did, on 5 April 2011 ...
And on 4 February 2010, quoted again on 5 April 2011
These arguments constitute a proper & detailed demonstration of that specific claim. Deal with them, or don't, but if you don't, then there is nothing more to say on this point.
As for the Onel & Mann paper (Generation of Large Scale Electric Fields in Coronal Flare Circuits, Central European Astrophysical Bulletin 33: 141-154, 2009), I will address it specifically in a later post. However, be aware of the point I am making here as regards Alfven: "Alfven established faulty boundary conditions because he was guided by a faulty paradigm, ... ". Nowhere in the Onel & Mann paper will you find any mention of Alfven's boundary conditions. Therefore the Onel & Mann paper is not relevant specifically to my claim that Alfven's boundary conditions are faulty.
tusenfem
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Why should I meet you i the middle, when you keep on continuing making false claims, repeating them all the time, even after you have been explained umpteen times why it is wrong?
For the last time:
Circuit theory is good to get the large scale properties of a plasma physical system, where all micro physics is hidden under the carpet that is called average large scale quantities such as there are resistivity, battery voltage, total induction, ..... described in the circuit by R, V, L .....
One can calculate what the total energy is in such a circuit, and that is completely equivalent with calculating the energy through integrating over all plasma and field energies (with the note: naturally only when you have estimated R, L etc correctly). That is it, yes, you can put in some more circuit units and then try to model some global "dynamics" which I think happens in the Onel & Mann papers.
HOWEVER, although in a lot of descriptions the magnetic field lines are called the "electric wires of the circuit" this only holds in some cases, e.g. it completely does not hold for the current sheet between two oppositely directed magnetic fields obviously. THEREFORE, a circuit cannot describe the full process of reconnection, because it cannot describe the change in topology of the magnetic field, it can describe, maybe, that currents will go from one circuit to another in some coupled system (which we once tried to develop, I vaguely remember .....)
Thus there is no middle ground, because for there to be a middle ground you need to know and understand the basics. I think that this Cowling paper gives an introduction of circuit theory. Unfortunately, it is not available online, so I cannot check here at the meeting.
Unfortunately, the talk from an current point of view was very disappointing. Akasofu made some good comments that looking at B or looking at j lines basically throws a filter over the data such that you eiter see one or the other. However, when applying it to some examples (mainly on the Sun) it was clear that he had not kept up with modern developments, but excused himself by saying "I am no solar physicist". Apparently, he has some ideas on the currents, but he did not present them. Only in the case of the Boström current system in the Earth's magnetotail he showed something that may indeed show that one needs to look a currents (which is being done, actually). In the end, it was a nice general talk, but could have been much better, but he did give some good advice to young scientists to try and find the snoopy pieces in the garfield puzzle.
Tim Thompson
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Onel & Mann, Circuits, and Real Plasma Physics
The Onel & Mann paper constructs a physical model of a flare, and then represents the physical model with a schematic electric circuit. It is important to note that it is not just a "circuit model", but rather a physical model (see figure 2) that is the represented by a circuit schematic (see figure 3). The circuit schematic is then analyzed in the normal fashion for an electric circuit and the results of that analysis are then correlated with the physical model and the observed behavior of a particular active region on the Sun. The authors determine that motions in the photosphere plasma are able to generate an electric field in the coronal loop which is aligned parallel to the magnetic field of the loop. That electric field is responsible for accelerating electrons in the loop and is the root cause of the observed flare. That's a summary of the paper; if you want to know more, you can read the original, which can be downloaded as PDF via the link provided above.
First, let me point out what the Onel & Mann paper is not.
As I quoted myself in the previous post: "Alfven established faulty boundary conditions because he was guided by a faulty paradigm, ... ". Nowhere in the Onel & Mann paper will you find any mention of Alfven's boundary conditions. Therefore the Onel & Mann paper is not relevant specifically to my claim that Alfven's boundary conditions are faulty.
Also consider the thread title, "Problems with Magnetic Reconnection". The primary topic of this magnetic reconnection. michaelsuede claims, and Mozina has long claimed, that magnetic reconnection does not & cannot happen. Nowhere in the Onel & Mann paper do we find any claim that magnetic reconnection cannot happen. We do find this: "The basic idea of this mechanism is to generate the flare energy by photospheric plasma motion in active regions. This is in contradiction to the reconnection model in which the magnetic field energy in the corona is taken for the flare." (arXiv preprint page 4). The authors clearly argue for an alternative to magnetic reconnection as an energy source for flares (or at least for the particular flare they are studying, though I am sure they mean this to be a more general claim). However, nowhere do the authors question the more fundamental validity of the magnetic reconnection process. So the paper is relevant to the role of magnetic reconnection in flares, but it is not relevant to the fundamental validity of magnetic reconnection.
Now let me repeat myself with slightly altered emphasis: "Alfven established faulty boundary conditions because he was guided by a faulty paradigm, ... ", that faulty paradigm being the circuit paradigm. Certainly "faulty" is an unfortunate choice of words, since it arguably puts me in the position of being self-contradictory, which fortunately for me went unnoticed by certain others ...
Certainly the circuit paradigm is not wrong or faulty in any general sense. However, it is an approximation of limited use. Better for me to say that Alfven was misled by an oversimplified paradigm, rather than a faulty one. So I will correct myself to that extent.
Not that I can see. But the only real point that one can take home from this is that the circuit paradigm is not wrong in the general sense. One can also argue, assuming that Onel & Mann make a valid point, that not all flare electrons are accelerated by magnetic reconnection. But then nobody ever made that claim that I am aware of anyway. The Onel & Mann paper says nothing at all about Alfven's boundary conditions, and I stand by my claim that they are faulty. Furthermore, the Onel & Mann paper says nothing at all about the fundamental validity of magnetic reconnection, and I stand by my claim that it is a valid physical process easily distinguished from induction, "circuit reconnection", or the Onel & Mann mechanism of a straight forward electric field.
But I will use a passage from Onel & Mann, along with my own earlier comments, to argue that "circuit reconnection", as I understand it to be meant, is not possible as an alternate explanation for the phenomena of magnetic reconnection.
I said ...
Onel & Mann say ... "Electrons gain energy only by electric field acceleration" (arXiv preprint page 10) ... "An electron traveling through an electron-proton plasma experiences Coulomb collisions, which always make the electron lose energy." .... (arXiv preprint page 11).
The "reconnection" of currents, especially currents flowing in opposite directions, will invariably cause the particles to lose energy, whereas magnetic reconnection invariably causes the particles to gain energy. Since the two processes work in the opposite sense, it hardly makes sense to claim that they are equivalent. Furthermore, the "reconnection" of currents does not generate a new electric field. So even if the currents ran parallel instead of anti-parallel, there would still be no physical mechanism whereby the particles (electrons) would gain rather than lose energy. And finally, as I have noted before, if one only considers the "reconnection" of particle streams, one must face the serious issue of conservation of energy, since the newly accelerated particles will carry far more kinetic energy than did their parent particle streams. All of this combines to make "current reconnection" or "circuit reconnection" or "particle reconnection" unworthy of reasonable consideration as a functionally equivalent process to magnetic reconnection.
This is an argument that I also reject, for two primary reasons. First, it is by no means obvious that the Onel & Mann paper is easily extended to include all flare events with all physical environments. It is, after all, only one paper, and the number of papers that use the same kind of circuit paradigm is quite limited, compared to the massive literature on flares & magnetic reconnection. But perhaps even more important is that "exotic energy release theory" is not at all correct. There is nothing "exotic" about magnetic reconnection theory, which is in fact highly un-exotic and a necessary consequence of Maxwell's equations. The truth of the matter is that the Onel & Mann model is rather more exotic than the magnetic reconnection model, because well behaved fields as proposed by Onel & Mann are certainly not the rule on the Sun, where a great deal more variability is to be expected. Furthermore, there are just as many cases where the observed behavior of a flare or CME event implies a magnetic reconnection mechanism rather than an Onel & Mann style electric field (e.g., Budget of energetic electrons during solar flares in the framework of magnetic reconnection, Mann & Warmuth, Astronomy & Astrophysics 528: A104, April 2011; that's the same Mann as in Onel & Mann, by the way; Reconnection Outflows and Current Sheet Observed with Hinode/XRT in the 2008 April 9 "Cartwheel CME" Flare, Savage, et al., Astrophysical Journal 722(1) 329-342, October 2010; Observations of the Magnetic Reconnection Signature of an M2 Flare on 2000 March 23, Leping & Zhang, Astrophysical Journal 703(1): 877-882, September 2009).
There is no good reason to declare that the Onel & Mann paper rules out magnetic reconnection in flares & CME events.
And finally, regarding the circuit paradigm in general ...
I agree with tusenfem, there is no "middle ground", and it is not true that the circuit orientation is "equally viable" or "equally well suited". As I said myself in a quote above, the circuit paradigm in an approximation which, as tusenfem correctly points out, hides all of the real physics that's going on in the plasma, behind a wall of averages & approximations. That's why Alfven failed to establish valid boundary conditions in the first place, because he used a paradigm that hides the real physics. He has to rule out local variables because his paradigm can't see them, but in the end appealing to those local variables is the one and only way to understand the real physics of real plasmas.
The Onel & Mann paper constructs a physical model of a flare, and then represents the physical model with a schematic electric circuit. It is important to note that it is not just a "circuit model", but rather a physical model (see figure 2) that is the represented by a circuit schematic (see figure 3). The circuit schematic is then analyzed in the normal fashion for an electric circuit and the results of that analysis are then correlated with the physical model and the observed behavior of a particular active region on the Sun. The authors determine that motions in the photosphere plasma are able to generate an electric field in the coronal loop which is aligned parallel to the magnetic field of the loop. That electric field is responsible for accelerating electrons in the loop and is the root cause of the observed flare. That's a summary of the paper; if you want to know more, you can read the original, which can be downloaded as PDF via the link provided above.
First, let me point out what the Onel & Mann paper is not.
As I quoted myself in the previous post: "Alfven established faulty boundary conditions because he was guided by a faulty paradigm, ... ". Nowhere in the Onel & Mann paper will you find any mention of Alfven's boundary conditions. Therefore the Onel & Mann paper is not relevant specifically to my claim that Alfven's boundary conditions are faulty.
Also consider the thread title, "Problems with Magnetic Reconnection". The primary topic of this magnetic reconnection. michaelsuede claims, and Mozina has long claimed, that magnetic reconnection does not & cannot happen. Nowhere in the Onel & Mann paper do we find any claim that magnetic reconnection cannot happen. We do find this: "The basic idea of this mechanism is to generate the flare energy by photospheric plasma motion in active regions. This is in contradiction to the reconnection model in which the magnetic field energy in the corona is taken for the flare." (arXiv preprint page 4). The authors clearly argue for an alternative to magnetic reconnection as an energy source for flares (or at least for the particular flare they are studying, though I am sure they mean this to be a more general claim). However, nowhere do the authors question the more fundamental validity of the magnetic reconnection process. So the paper is relevant to the role of magnetic reconnection in flares, but it is not relevant to the fundamental validity of magnetic reconnection.
Now let me repeat myself with slightly altered emphasis: "Alfven established faulty boundary conditions because he was guided by a faulty paradigm, ... ", that faulty paradigm being the circuit paradigm. Certainly "faulty" is an unfortunate choice of words, since it arguably puts me in the position of being self-contradictory, which fortunately for me went unnoticed by certain others ...
Certainly the circuit paradigm is not wrong or faulty in any general sense. However, it is an approximation of limited use. Better for me to say that Alfven was misled by an oversimplified paradigm, rather than a faulty one. So I will correct myself to that extent.
Not that I can see. But the only real point that one can take home from this is that the circuit paradigm is not wrong in the general sense. One can also argue, assuming that Onel & Mann make a valid point, that not all flare electrons are accelerated by magnetic reconnection. But then nobody ever made that claim that I am aware of anyway. The Onel & Mann paper says nothing at all about Alfven's boundary conditions, and I stand by my claim that they are faulty. Furthermore, the Onel & Mann paper says nothing at all about the fundamental validity of magnetic reconnection, and I stand by my claim that it is a valid physical process easily distinguished from induction, "circuit reconnection", or the Onel & Mann mechanism of a straight forward electric field.
But I will use a passage from Onel & Mann, along with my own earlier comments, to argue that "circuit reconnection", as I understand it to be meant, is not possible as an alternate explanation for the phenomena of magnetic reconnection.
I said ...
Onel & Mann say ... "Electrons gain energy only by electric field acceleration" (arXiv preprint page 10) ... "An electron traveling through an electron-proton plasma experiences Coulomb collisions, which always make the electron lose energy." .... (arXiv preprint page 11).
The "reconnection" of currents, especially currents flowing in opposite directions, will invariably cause the particles to lose energy, whereas magnetic reconnection invariably causes the particles to gain energy. Since the two processes work in the opposite sense, it hardly makes sense to claim that they are equivalent. Furthermore, the "reconnection" of currents does not generate a new electric field. So even if the currents ran parallel instead of anti-parallel, there would still be no physical mechanism whereby the particles (electrons) would gain rather than lose energy. And finally, as I have noted before, if one only considers the "reconnection" of particle streams, one must face the serious issue of conservation of energy, since the newly accelerated particles will carry far more kinetic energy than did their parent particle streams. All of this combines to make "current reconnection" or "circuit reconnection" or "particle reconnection" unworthy of reasonable consideration as a functionally equivalent process to magnetic reconnection.
This is an argument that I also reject, for two primary reasons. First, it is by no means obvious that the Onel & Mann paper is easily extended to include all flare events with all physical environments. It is, after all, only one paper, and the number of papers that use the same kind of circuit paradigm is quite limited, compared to the massive literature on flares & magnetic reconnection. But perhaps even more important is that "exotic energy release theory" is not at all correct. There is nothing "exotic" about magnetic reconnection theory, which is in fact highly un-exotic and a necessary consequence of Maxwell's equations. The truth of the matter is that the Onel & Mann model is rather more exotic than the magnetic reconnection model, because well behaved fields as proposed by Onel & Mann are certainly not the rule on the Sun, where a great deal more variability is to be expected. Furthermore, there are just as many cases where the observed behavior of a flare or CME event implies a magnetic reconnection mechanism rather than an Onel & Mann style electric field (e.g., Budget of energetic electrons during solar flares in the framework of magnetic reconnection, Mann & Warmuth, Astronomy & Astrophysics 528: A104, April 2011; that's the same Mann as in Onel & Mann, by the way; Reconnection Outflows and Current Sheet Observed with Hinode/XRT in the 2008 April 9 "Cartwheel CME" Flare, Savage, et al., Astrophysical Journal 722(1) 329-342, October 2010; Observations of the Magnetic Reconnection Signature of an M2 Flare on 2000 March 23, Leping & Zhang, Astrophysical Journal 703(1): 877-882, September 2009).
There is no good reason to declare that the Onel & Mann paper rules out magnetic reconnection in flares & CME events.
And finally, regarding the circuit paradigm in general ...
I agree with tusenfem, there is no "middle ground", and it is not true that the circuit orientation is "equally viable" or "equally well suited". As I said myself in a quote above, the circuit paradigm in an approximation which, as tusenfem correctly points out, hides all of the real physics that's going on in the plasma, behind a wall of averages & approximations. That's why Alfven failed to establish valid boundary conditions in the first place, because he used a paradigm that hides the real physics. He has to rule out local variables because his paradigm can't see them, but in the end appealing to those local variables is the one and only way to understand the real physics of real plasmas.
On the topic of the circuit "paradigm": it reminds me of the idea of hydraulic equivalent circuit. Given a plumbing system consisting of sealed pipes and open reservoirs (excluding certain common elements like rubber bladders) you can represent the pressure P as relating to moving masses M of water:
P = dM/dt*R + d^2M/dt^2*L + M*C
The pipes have a resistance, such that pressure drop is approximately proportional to flow rate dM/dt---just like resistance. Water has inertia, so changing a flow rate requires a force proportional to d^2M/dt^2---just like inductance Reservoirs have more inlet pressure depending on how charged-up they are, so it's proportional to M---just like capacitance. So if I give you a plumbing system, you can go through it (or measure it) and ... well, sure you can write down a circuit model---you go through the pipe diameters, lengths, roughnesses, etc., and calculate R; you go through the water mass and calculate L; etc. And that'll give good response functions for that plumbing system.
But it's not the whole story. Nobody would ever say that fluid dynamics engineers are "missing something" because they "ignore circuit orientation". First, they don't ignore it. Secondly, the circuit orientation is a way of *ignoring* the small-scale details. (A long wide pipe and a short narrow pipe may have the same R---so the circuit model thinks they're the same---but that doesn't mean they're the same if you care about mixing, or ability to flush solids, or behavior under water hammers.) Third, the circuit orientation is indeed an approximation. Oddly-shaped reservoirs have some other, non-capacitor-like pressure equation P = f(M). Open channel flow has non-resistor-like P = f(dM/dt). Some interesting phenomena, like the hydraulic jump of faucet flow into a nearly-empty sink, are simply beyond of the list of variables that the circuit model cares about.
So you use a circuit model when (a) you already know the microphysics (or the impulse response data) that allows you to figure out R, L, C, and (b) when you explicitly don't care that you're going to miss mixing, flushing, hydraulic jumps, etc..
Saying that the circuit model is better is not even wrong, it's a non-sequitur. The circuit model is what you end up with if you take whatever actual physics you know, then lump together terms with the same order derivatives. It's not supposed to be "better", it's supposed to be a simplification.
P = dM/dt*R + d^2M/dt^2*L + M*C
The pipes have a resistance, such that pressure drop is approximately proportional to flow rate dM/dt---just like resistance. Water has inertia, so changing a flow rate requires a force proportional to d^2M/dt^2---just like inductance Reservoirs have more inlet pressure depending on how charged-up they are, so it's proportional to M---just like capacitance. So if I give you a plumbing system, you can go through it (or measure it) and ... well, sure you can write down a circuit model---you go through the pipe diameters, lengths, roughnesses, etc., and calculate R; you go through the water mass and calculate L; etc. And that'll give good response functions for that plumbing system.
But it's not the whole story. Nobody would ever say that fluid dynamics engineers are "missing something" because they "ignore circuit orientation". First, they don't ignore it. Secondly, the circuit orientation is a way of *ignoring* the small-scale details. (A long wide pipe and a short narrow pipe may have the same R---so the circuit model thinks they're the same---but that doesn't mean they're the same if you care about mixing, or ability to flush solids, or behavior under water hammers.) Third, the circuit orientation is indeed an approximation. Oddly-shaped reservoirs have some other, non-capacitor-like pressure equation P = f(M). Open channel flow has non-resistor-like P = f(dM/dt). Some interesting phenomena, like the hydraulic jump of faucet flow into a nearly-empty sink, are simply beyond of the list of variables that the circuit model cares about.
So you use a circuit model when (a) you already know the microphysics (or the impulse response data) that allows you to figure out R, L, C, and (b) when you explicitly don't care that you're going to miss mixing, flushing, hydraulic jumps, etc..
Saying that the circuit model is better is not even wrong, it's a non-sequitur. The circuit model is what you end up with if you take whatever actual physics you know, then lump together terms with the same order derivatives. It's not supposed to be "better", it's supposed to be a simplification.
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CaveDave
Semicentenarian Troglodyte
