Magnetic reconnection and physical processes

[Ziggurat]

No, it's a PHYSICS complaint. You are ignoring or not recognizing the actual physical energy exchange process. At it's most basic level, it is a kinetic energy transfer process between moving charged particles.

You're wrong, as I explained above. Energy stored in magnetic fields is NOT the same as the kinetic energy of the charge carriers. Consult any electrodynamics textbook.

Would you agree that we could also rightly call this process "circuit reconnection" or "particle reconnection"?

No, I would not.

 

[ben m]

In that case the "stored magnetic energy" you're talking about is kinetic energy in the one coil that is transferred to the secondary coil. It's still a "kinetic energy" transfer event. The same is true in all 'magnetic reconnection" events in the solar atmosphere.

Fail. How is it possible to get this wrong? There's kinetic energy (sum of 1/2 mv^2 for all particles) and magnetic field energy (integral B^2 over space), and these are totally separate and unrelated things. Heck, the kinetic energy in ordinary electrical circuits is vanishingly small since the charge carriers are so slow. How is it possible to pretend to argue about magnetic fields and not know how they work?? On the other hand: No wonder MM thinks mainstream astro is all wrong. He's been arguing about physics in a world where mu_nought is vanishingly small; we've been answering him in a world where it is 4*pi x 10^-7 N/A^2. Those worlds are different. The latter is real.

Even in plasma physics, either kinetic or magnetic energy can be made to dominate, and there's standard terminology for both cases. Care to guess what dominates the solar corona?

 

[sol invictus]

The problem of course is that in the solar atmosphere, that statement is utterly inapplicable. There is nowhere in interstellar space that is a "pure vacuum", and nowhere in interplanetary or interstellar space where current flow is not occurring.

The density of matter in interstellar space is approximately 1 proton per cubic meter. So let's say I make a magnetic field in a cubic meter sized region out there. All its energy stored in that one proton? Wow!!

I'd also be interested to hear where you think the energy in the field of a bar magnet comes from. Or in radio waves, say the ones transmitted from satellite to satellite. Or sunlight spreading out into space. Etc. Etc.

This is basic, high school physics. It's been understood since the mid 1800s. What you are saying is totally and completely wrong - and it makes very clear that you have no understanding or knowledge of even the most basic principles of electromagnetism.

Fail.

 

[Michael Mozina]

You're wrong, as I explained above. Energy stored in magnetic fields is NOT the same as the kinetic energy of the charge carriers. Consult any electrodynamics textbook.

Nobody is denying this. At the point of "reconnection" however, the energy transfer process is primarily is a kinetic energy transfer process, and perhaps a wee bit of induction energy, but there is no possibility that any energy is gained via "magnetic reconnection" because it is physically impossible for magnetic lines to disconnect or reconnect.

No, I would not.

The you will need to tell me how we can determine if this is in fact a unique form of energy exchange because Alfven called your beliefs "pseudoscience". Either Alfven didn't know what he was talking about or you do not. Both of you cannot be correct.

Page 16, of Cosmic Plasma:

There is no need for `frozen-in' field lines moving with the plasma, still less for `field-line reconnection' or `magnetic merging' . The magnetic field always remains static and not a single field line is `disconnected' or `reconnected'. The energy of a charged particle is given by Equation (6) . There is no 'field-line reconnection' that can transfer energy to the particles or release energy in any other way. Other arguments against reconnection models are forewarded by Heikkila (1978).

Now whom shall I believe was the better expert on MHD theory, the guy that wrote the theory and won the Nobel prize, or some guy I met on the internet?

 

[Michael Mozina]

Fail. How is it possible to get this wrong? There's kinetic energy (sum of 1/2 mv^2 for all particles) and magnetic field energy (integral B^2 over space), and these are totally separate and unrelated things. Heck, the kinetic energy in ordinary electrical circuits is vanishingly small since the charge carriers are so slow.

First of all, none of this is the least bit relevant in *plasma* where the charged particles are whizzing by at a million miles per hour! In the case of the coil, you have current flow in the coil and EM energy being transferred via induction. There is absolutely no form of "magnetic reconnection" going on in the coil.

How is it possible to pretend to argue about magnetic fields and not know how they work??

I know how they work in solids *and* in plasma and they don't work precisely the same way in both environment because in plasma every movement of a charged particle is a form of 'current flow' and the ions move too! You can't treat them exactly the same and not pay attention to the physics of what's going on in plasma.

Even in plasma physics, either kinetic or magnetic energy can be made to dominate, and there's standard terminology for both cases. Care to guess what dominates the solar corona?

Electrical discharges! Care to explain how the sun sends out charged particles in a full spherical pattern? Come on. We point Rhessi at the Earth and see gamma rays from lightning on Earth. We point the same piece of gear at the sun, see the same types of gamma rays, and you guys claim "magnetic reconnection did it"? Give it a rest. Only "electrical current" has been shown to heat plasma to millions of degrees, pinch free neutrons from plasma, emit gamma rays and x-rays galore. It is *electrical current* the dominates events in the corona and magnetic lines of physically incapable of "reconnecting" in the "real world".

 

[Michael Mozina]

The density of matter in interstellar space is approximately 1 proton per cubic meter.

Let's talk about the solar atmosphere where you claim "magnetic reconnection" occurs. The density is higher than in interstellar space. Even in an ordinary plasma ball, the low pressure inside the sphere is no impediment to the formation of higher density current carrying filaments. So what if the density is relative low? Electrical current is going to create "z-pinched" filaments in the plasma just like we observe in an ordinary plasma ball.

So let's say I make a magnetic field in a cubic meter sized region out there. All its energy stored in that one proton? Wow!!

What "'magnetic field" in interstellar space? The only reason you have a "magnetic field" out in space to begin with is due to the "current flow" that creates it. No wonder you guys are so messed up when it comes to physics.

I'd also be interested to hear where you think the energy in the field of a bar magnet comes from.

Charged particle alignment inside the solids. In plasma however, nothing is stable and all moving charged particles create "current flow".

Or in radio waves,

Er, those would be "photons'.

Or sunlight spreading out into space. Etc. Etc.

Those are photons too.

I want to hear you explain how the sun emits million mile per hour particles from every direction and how it manages to accelerate the particles continuously from around the whole sphere, day after day, week after week, year after year.

This is basic, high school physics. It's been understood since the mid 1800s.

No, it's MHD theory applied to current carrying plasma, and it's *MUCH* trickier than you think.

What you fail to understand is that if we look at that ordinary plasma ball with the ability to detect magnetic fields, we will certainly see "magnetic flux tubes" inside the plasma. The "flux" is the "particle flow", and the tube configuration is a tornado like filament composed of moving charged particles.

As long as you keep looking at this problem from the perspective of "high school physics", you'll never make any sense of anything, and that solar wind 'mystery' will never be solved. You guys oversimplify the physics of everything you look at and pretend to be quite the "experts". When we look at your grasp of the actual *physics* behind the process however, its oversimplified nonsense.

 

[Ziggurat]

Nobody is denying this.

Oh, but you are. Or were. Ben said,
"When you unplug an inductive load (like an iron, or a transformer) from the wall and it makes a spark, that spark is discharging the stored magnetic energy." (post 37)
You responded by saying
"In that case the "stored magnetic energy" you're talking about is kinetic energy in the one coil that is transferred to the secondary coil. It's still a "kinetic energy" transfer event." (post 39)

But this completely wrong. The spark is NOT from kinetic energy of the electrons (which is negligible), but from energy stored in the magnetic field. Now you want to deny having made this claim. Go ahead: but your post is right there for all to see.

 

[sol invictus]

Let's talk about the solar atmosphere where you claim "magnetic reconnection" occurs.

Let's see - you said something really stupid. When called on it, you claimed it held in every "physical" situation, and specifically mentioned interstellar space. When called on that, you retreated again.

Guess what - you're still wrong, even in the solar atmosphere.

Er, those would be "photons'.

You obviously have no idea what that means, because if you did you would know that you've just contradicted yourself yet again. Photons are the electromagnetic fields.

This is like arguing with a stubborn ten year old. Except that most children are capable of learning something.

 

[ben m]

First of all, none of this is the least bit relevant in *plasma* where the charged particles are whizzing by at a million miles per hour!

It's exactly relevant. You can calculate the kinetic energy of the electrons and ions. You can calculate the energy in the magnetic field. They are separate quantities; they both exist; they have separate effects. (There's also free photon energy density, which can be treated distinctly from both.)

I know how they work in solids *and* in plasma and they don't work precisely the same way in both environment because in plasma every movement of a charged particle is a form of 'current flow' and the ions move too! You can't treat them exactly the same and not pay attention to the physics of what's going on in plasma.

Moving charged particles all count as current; current generates a magnetic field. Sounds like Maxwell's Equations to me and to the rest of the world. Where do you think plasma physicists found all of those "instabilities" you're so fond of? By solving the (perfectly normal) Maxwell's behavior of (perfectly normal) currents and fields, which happen to be carried by free ions and electrons.

Only "electrical current" has been shown to heat plasma to millions of degrees, pinch free neutrons from plasma, emit gamma rays and x-rays galore.

Actually, we've seen plasma heating done with magnetic induction, radiation, reconnection, acoustic shocks, and magnetohydrodynamic shocks.

But I see again where you're coming from---in the fictional universe where mu_0 is very small, and magnetic fields can't store energy, then electric current (and ion momentum) *would* be a good way to heat up a plasma! In such a world the Sun's corona wouldn't be magnetic-pressure dominated, and reconnection wouldn't work. That's a fine alternate reality, MM, but if you want to discuss the real world please learn how big mu_0 is and learn how much energy is stored in the corona's magnetic fields, eh?

 

[Michael Mozina]

This is simply false, as even a little bit of consideration would demonstrate.

http://www.phy.bris.ac.uk/groups/hreg/MagneticFieldStrength.htm

I'm assuming we're arguing now about the difference between "magnetic field strength" and "magnetic flux density"? Keep in mind that the carrier particles of the EM field are photons. The flux density and field strength are therefore measured differently.

 

[sol invictus]

http://www.phy.bris.ac.uk/groups/hreg/MagneticFieldStrength.htm

You remind me of humber from the validity of classical physics thread. You post the same ridiculously wrong statements over and over, and when challenged you link to sites that do not support your claims in any way. When challenged on those you go back to your original claim. Rinse and repeat.

I'm assuming we're arguing now about the difference between "magnetic field strength" and "magnetic flux density"? Keep in mind that the carrier particles of the EM field are photons. The flux density and field strength are therefore measured differently.

Nonsensical word salad. You're randomly spewing technical terms you don't understand.

 

[ben m]

http://www.phy.bris.ac.uk/groups/hreg/MagneticFieldStrength.htm

I'm assuming we're arguing now about the difference between "magnetic field strength" and "magnetic flux density"? Keep in mind that the carrier particles of the EM field are photons. The flux density and field strength are therefore measured differently.

Did that come up in a Google search for "Random facts about magnetic fields"? Which statement in the above discussion hinges oh-so-critically on the distinction between B and H? After a lifetime of assuming mu=0, are you now going to take a stab at assuming mu > m_0 (which is, let's be honest, the only time anyone cares about H) to compensate?

 

[Michael Mozina]

Did that come up in a Google search for "Random facts about magnetic fields"? Which statement in the above discussion hinges oh-so-critically on the distinction between B and H? After a lifetime of assuming mu=0, are you now going to take a stab at assuming mu > m_0 (which is, let's be honest, the only time anyone cares about H) to compensate?

No, the keywords were "current density magnetic field strength". They are related. The magnetic field would not even exist in the interplanetary plasma were it not for the "current flow" that sustains it!

I can see that this is going to be another of those discussions where we got lost in trivia and ignore the basic facts. The basic facts are that magnetic lines lack physical substance and are physically incapable of "disconnecting" or "reconnecting". The rest is just pure ego posturing.

 

[sol invictus]

I can see that this is going to be another of those discussions where we got lost in trivia and ignore the basic facts. The basic facts are that magnetic lines lack physical substance and are physically incapable of "disconnecting" or "reconnecting". The rest is just pure ego posturing.

It's basic facts that you lack.

Do you really expect to be taken seriously if you can't even get the basics right? Your credibility is totally shot - it's now very clear that you don't have even 100 level knowledge of these topics.

What's astonishing is that you're so incredibly arrogant about it - you don't just challenge standard results (that have massive experimental and theoretical support), you ridicule the whole field, and imply there's a conspiracy to hide the truth.

It's pathological - my guess, based on the evidence in these posts, would be paranoid schizophrenic.

 

[Ziggurat]

http://www.phy.bris.ac.uk/groups/hreg/MagneticFieldStrength.htm

I'm assuming we're arguing now about the difference between "magnetic field strength" and "magnetic flux density"?

No, we are not. We are talking about whether or not the energy stored in, say, a solenoid is stored in the magnetic field or in the kinetic energy of the electrons. You claimed the later in post 39, but have since apparently backed off.

The only significant distinction the page page you linked to makes is between B and H. Many authors call H the magnetic field, but that's bad terminology, since B is the fundamental quantity, not H. Note that this is a semantic objection on my part: everyone who knows what they're doing understands what is B and what is H, even if they don't use the same names. I call B the magnetic field, and H the applied field (Griffiths doesn't even use any term for H).

I'm really not sure why you linked to that page, though, because the distinction between B and H is irrelevant here.

Keep in mind that the carrier particles of the EM field are photons. The flux density and field strength are therefore measured differently.

B is B. Call it whatever you want, but when you want to calculate the energy stored in a magnetic field, B is what matters, not H.

 

[Michael Mozina]

Let's see - you said something really stupid. When called on it,

No. I said something very basic and rather generic. Evidently you built a quaint little strawman from my words and lit it up like a Christmas tree.

 

[Ziggurat]

No. I said something very basic and rather generic.

Yes, it was basic and generic. It was also totally wrong. Just for clarification, we're still talking about your response (post #39) to ben (post #37), where you claimed that the energy stored in an inductive circuit comes from electron kinetic energy. You have tried to deny saying what you said (post #44), but that's not helping you at all.

 

[Michael Mozina]

Yes, it was basic and generic. It was also totally wrong. Just for clarification, we're still talking about your response (post #39) to ben (post #37), where you claimed that the energy stored in an inductive circuit comes from electron kinetic energy. You have tried to deny saying what you said (post #44), but that's not helping you at all.

Since all three of you seem to be stuck on this point, I'll go back and reread the post in question and your complaints and see what I'm missing. With three different threads going now, I'm having trouble keeping up with all of them and I'd admit my language has been sloppy at times, and I haven't done a lot of proofreading, but I really don't understand your objection to my statement. The current density and field strength are related. The movement of the electrons generates the field. The termination of the electron flow causes the field to collapse. It's all related to the movement of charged particles.

I think I'll have to chew on your comments awhile, reread my post and see I can understand your actual objection, because right now, it makes no sense to me.

 

[ben m]

No, the keywords were "current density magnetic field strength". They are related. The magnetic field would not even exist in the interplanetary plasma were it not for the "current flow" that sustains it!

In that case, insofar as the link was to a totally standard treatment of E&M, then it supports the totally standard case, which we've been repeating to you, that (a) Magnetic field energy comes from B^2, not from the kinetic energy of the current source, (b) "reconnection" is a perfectly valid description of a perfectly valid configuration of magnetic fields, and (c) the field configuration known as "reconnection" is one that converts energy from magnetic field energy into other forms of energy, like kinetic energy or heat.

I can see that this is going to be another of those discussions where we got lost in trivia and ignore the basic facts. The basic facts are that magnetic lines lack physical substance and are physically incapable of "disconnecting" or "reconnecting". The rest is just pure ego posturing.

This isn't a distraction: you are claiming that the "evidence" for your "basic fact" are (a) magnetic fields don't store energy, (b) field lines are meaningless, (c) reconnection can't happen, and (d) now B and H differ by a factor of mu. We are disputing your fact by disputing each of your lines of "evidence". (a) is a flat falsehood, (b) is either a flat falsehood or a boneheaded misunderstanding of the difference between a vector field and a drawing of a vector field, we have supplied an explicit counterexample to (c), and (d) is irrelevant. Which "basic fact" did you want to discuss again?

 

[ben m]

The magnetic field would not even exist in the interplanetary plasma were it not for the "current flow" that sustains it!

And I get the feeling that you keep coming back to "current flow" because you want to justify putting large electrostatic fields in space. Let's just head that off at the pass, shall we?

We've agreed (repeatedly) that magnetic fields are generated by currents. Not very surprising; it's all B = del cross J as usual. Tell me J and I'll tell you B, and vice versa, modulo a constant of integration. Where are those Js coming from? You want them to come from J = sigma E, Ohm's law, or F = qE. And you want those Es to come from charge separation. Is that a fair statement?

You've got Maxwell's equations in front of you: grad E = rho (charge separation) and curl E = -dB/dt. Standard astrophysics isn't "there's no E in space", standard astrophysics is "there's usually no grad E in space". Space charge separations are small, rare, and generally transient. You get currents in plasma because of changing, usually turbulent, magnetic fields; those currents generate their own changing fields, which generate more currents, and this generates complex plasma dynamics and waves in the absence of charge separation. That's standard astrophysical plasmas: Grad E ~= 0. Curl E != 0. Curl B != 0. Not "J=0", not "there's no plasma", not "plasma is unimportant", not "the current is bunched into discrete ropes or lines". Is that clear? If you've got a coherent objection to mainstream astrophysics at all, that objection is "I think that grad E != 0 configurations are an important/dominant source of currents" Is that a fair statement? "You ignore currents" is a false premise. "Maxwell's Equations don't apply" is ... well, let me just say wrong.

Since dB/dt implies some sort of B to begin with, we need a "primary" source of currents. You want to put big charge separations on or near the Sun to push a "primary" Ohm's Law (nor Coulomb's Law) current around. This would be sort of a reasonable wacky hypothesis ... if you, MM, had shown us that you were *generally quite good* with Maxwell's Equations, and that *your best effort* at getting non-Ohms-law currents had failed and that this idea worked better. Instead, you've shown us that someone who doesn't understand Freshman E&M also doesn't understand where solar currents come from. Anyway, there's a perfectly good mainstream explanation for where solar surface fields come from. Why don't you read up on it, with your newfound understanding of E&M, and explain it to us? Give us the Devil's Advocate version before you launch into what you think are its flaws.

As an other exercise---there's one very common piece of lab equipment (ubiquitous in teaching labs, found in specialized research labs) in which an electric current is created, but *not* driven by an electric field (though such a field happens to be present) or a changing magnetic field. Can you name it? It's tangentially relevant to the mainstream heliomagnetic and geomagnetic models.