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Magnetic reconnection and physical processes

The Man said:
Yes, it is just a matter of the energy stored in the reconnecting fields and the presence of a highly conductive media like plasma.
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The "ruse" here is your claim that the energy is stored in the "reconnecting" fields. It's simply stored energy in the *COMBINED* EM fields that is released again just like if we used a spring to achieve the same goal. There's no 'reconnection" taking place, just a transfer of energy back and forth, in and out of the combined fields. The term "reconnection" has nothing to do with it.
 
Michael Mozina said:
So you just demonstrated that "circuit reconnection" and "magnetic reconnection" are exactly the same physical process.
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Hardly, as a circuit description of the flux tube implicitly assumes long wavelengths (which is compatible with MDH although MHD is valid on smaller scales) and thus any reconnection, which is a small scale, i.e. smaller than the ion diffusion region, cannot in detail be described by a circuit.

Please, I ask for the umpteenth time, show a detailed model of your circuit reconnection. Just claiming something is so does not make it so.
 
tusenfem said:
From a quick look it seems they are claiming electric fields are generated by shear and accelerate electrons which create Xrays. Seems to me they are rehashing stuff that has been done in the late 80s early 90s, only now with RHESSI observations.
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Amazing. You folks insist upon math and insist upon published papers. Even when they are handed to you on a silver platter, you simply ignore them. Hoy.
 
Reality Check said:
The last post reminded me about a question that I have not seen answered yet:

So:

First asked 27 January 2010
Zeuzzz,
What is your source for your assertion that the reconnection rate is set arbitarily in MHS simulations?
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My source was very well known geophysical expert and ex director of the geophysical institute Syun Ichi Akasofu

See his wiki here: http://en.wikipedia.org/wiki/Syun-Ichi_Akasofu

The one that wrote the paper that tusenfem does not like, published in a plasma cosmology journal.

If you want to read the full text I have uploaded it here, but it has a maximum viewing number of 20 views as its copyrighted.

To quote:

The concepts of both the magnetic flux transfer and of the
magnetospheric plasma convection have been very useful in
interpreting various magnetospheric and ionospheric phenomena.
The question here is whether these two concepts are an
ultimate “tool” in understanding substorms. Although many
MHD simulations were successful in reproducing substormlike
features, they have not actually elucidated a chain of processes
that lead to a substorm onset, partly because the reconnection
rate is arbitrarily set. Another problem is that positive ions are
likely to be unmagnetized in the central part of the plasma sheet,
indicating that the frozen-in-field concept is not valid there.
Furthermore, there is no definitive observation of a large-scale
convection on the equatorial plane, which can be inferred from
the ionospheric potential structure. A recent study also shows
that there is no definitive observation of magnetic reconnection
within a distance of 10 RE. [......]

The simplest qualitative discussions can be more useful than
elaborate MHD simulations based on unsubstantiated guiding
concepts. History tells us that some of what is thought to be
“truth” in science is often only an agreement or understanding,
which is either right or wrong, among contemporary scientists.
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Tusenfem, if you dont like the paper then show whats wrong with the models he proposed. Dont just show that there are other magnetic reconnection theories if you cant falsify the alternatives put forward. I already quoted some on the first page of this thread complete with figures.

And the point about magnetic fields I was trying to make was not that they dont exist, just that a magnetic field in itself is not physical but effects physical things, so can be accurately measured. By physical I mean matter as opposed to space. >99.999% of space is empty if once considers the amount of empty space in an atom compared to the nucleus. Or you can take the four main states of matter and say that 99.9% of matter is in the plasma state. I think the conversation I was having earlier was just going round in circles, talking about semantics.

Still no-ones stated the type of energy conversion that happens in "magnetic reconnection", let alone any physical (kinetic, thermal, inductive?) effects it has.
 
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tusenfem said:
Hardly, as a circuit description of the flux tube implicitly assumes long wavelengths (which is compatible with MDH although MHD is valid on smaller scales) and thus any reconnection, which is a small scale, i.e. smaller than the ion diffusion region, cannot in detail be described by a circuit.
Click to expand...

Did you even read that paper? Did they use the term "circuit" anywhere in that paper?
 
tusenfem said:
Please, I ask for the umpteenth time, show a detailed model of your circuit reconnection. Just claiming something is so does not make it so.
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My "model" is evidently exactly the same as yours. If you want to see the math describing "circuit reconnection", take your own formulas and convert them to an E orientation of MHD theory.
 
Michael Mozina said:
My "model" is evidently exactly the same as yours. If you want to see the math describing "circuit reconnection", take your own formulas and convert them to an E orientation of MHD theory.
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You convert them. It's your model. Oh, wait, quote marks around the word "model". Obviously you've redefined the word to mean something other than the commonly accepted definition. Care to fill us in?

:dl:​
 
GeeMack, do you ever discuss the subject at hand? Or only ever the people discussing it?
 
Zeuzzz said:
And the point about magnetic fields I was trying to make was not that they dont exist, just that a magnetic field in itself is not physical but effects physical things, so can be accurately measured. By physical I mean matter as opposed to space.
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That's a very odd definition of physical or unphysical. Usually, in my experience anyway, when people say something (some theory or whatever) is "unphysical" they mean it violates some well established law of physics. But by your definition Maxwell's equations are unphysical.
 
Tubbythin said:
That's a very odd definition of physical or unphysical. Usually, in my experience anyway, when people say something (some theory or whatever) is "unphysical" they mean it violates some well established law of physics. But by your definition Maxwell's equations are unphysical.
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They are in essense field equations, which are by definition not physical.
 
Zeuzzz said:
Someone needs to read up on field theory I think.

Try these:

Field (mathematics) http://en.wikipedia.org/wiki/Field_(mathematics)
Vector field http://en.wikipedia.org/wiki/Vector_field
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Where I come from something that is physical is something that obeys the laws of physics. Something that is unphysical is something that does not obey the laws of physics.
As far as I can tell, per your definition, nothing outside of the Standard Model is physical.
No wonder these threads go round and round in circles.
 
Zeuzzz said:
They are in essense field equations, which are by definition not physical.
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What is physical according to you, Zeuzzz? Can you give us an example?

And before you say "matter", bear in mind that matter is composed entirely of excitations that obey field equations, just like photons and electromagnetic fields.
 
Fields are Physical

sol invictus said:
What is physical according to you, Zeuzzz? Can you give us an example? And before you say "matter", bear in mind that matter is composed entirely of excitations that obey field equations, just like photons and electromagnetic fields.
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Too late, he already said "matter" (emphasis mine) ...
Zeuzzz said:
And the point about magnetic fields I was trying to make was not that they dont exist, just that a magnetic field in itself is not physical but effects physical things, so can be accurately measured. By physical I mean matter as opposed to space. >99.999% of space is empty if once considers the amount of empty space in an atom compared to the nucleus. Or you can take the four main states of matter and say that 99.9% of matter is in the plasma state. I think the conversation I was having earlier was just going round in circles, talking about semantics.
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For the record, I personally reject the Zeuzzz definition of "physical". There can be no doubt at all that magnetic & electric fields are every bit as "physical" as any matter you can imagine. Otherwise, how does one make sense of pair production where energy transforms into matter or pair annihilation where matter transforms into energy. Are we watching the physical become unphysical and then physical again? What kind of sense does that make?
 
Ok I was wrong the whole idea of fields being non physical is not at all relevant to the discussion at hand however.

Address the relevant material at your will.
 
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