|
Welcome to the International Skeptics Forum, where we discuss skepticism, critical thinking, the paranormal and science in a friendly but lively way. You are currently viewing the forum as a guest, which means you are missing out on discussing matters that are of interest to you. Please consider registering so you can gain full use of the forum features and interact with other Members. Registration is simple, fast and free! Click here to register today. |
29th March 2011, 12:04 PM | #161 |
Banned
Join Date: Feb 2009
Posts: 9,361
|
|
29th March 2011, 12:06 PM | #162 |
Illuminator
Join Date: Mar 2008
Posts: 3,202
|
|
29th March 2011, 12:08 PM | #163 |
Illuminator
Join Date: Mar 2008
Posts: 3,202
|
Michael M, what are your views on Michael S's claim that "MHD theory is a load of junk science"?
|
29th March 2011, 12:08 PM | #164 |
Illuminator
Join Date: May 2008
Posts: 3,197
|
Methinks, you are mixing up Alfvén with Birkeland.
Not double layers were predicted, but field aligned currents. Double layers were already studied in some form by Langmuir. The real study in the lab was started by Schoenhuber in the late 50s. Alfvén did propose that they might exist above the auroral regions. |
__________________
Scientific progress goes *BOINK* -- Calvin & Hobbes twitter: @tusenfem -- Super Duper Space Plasma Physicist |
|
29th March 2011, 12:09 PM | #165 |
Graduate Poster
Join Date: Mar 2011
Posts: 1,565
|
I understand your argument, and I also understand why it doesn't hold up as refuting the circuit theory cause of reconnection. You are arguing that the DL can't accelerate particles in the direction of observed reconnection. The paper I just linked demonstrates that this is not true.
You can model the center of a current sheet just fine using MHD. However, you will not be able to actually give reasons for anything that is observed there without using circuit theory to explain the causative agents behind the instabilities. And you also can't use MHD to describe what results from those instabilities, such as the formation of double layers. |
29th March 2011, 12:09 PM | #166 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 28,521
|
No this is not the source of energy increase in magnetic reconnection. Double layers and magnetic reconnection are two separate phenomena. They generally occur separately.
There are situations in which evidence for both have been observed. e.g. some solar flares (caused by magnetic reconnection) emit beams of electrons that are thought to be accelerated by DL. |
__________________
NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
|
29th March 2011, 12:15 PM | #167 |
Banned
Join Date: Feb 2009
Posts: 9,361
|
I think I felt the same way that Alfven felt and that Michael S still feels about it until I read Birn's paper. It became incredibly clear from those debates (at space.com) that it was "circuits" and "particles" doing the actual "reconnection' inside of a "double layer". Whereas Alfven literally "rejected" the whole B orientation under such conditions, I couldn't personally bring myself to do that. The B's however can be converted to E's and the whole thing becomes a PARTICLE/CIRCUIT problem. I too prefer the particle/circuit orientation in current carrying plasma so I call it "circuit reconnection". It's not actually any magnetic lines that do any "reconnecting", it's the circuits and the particles that "reconnect" (literally slam into one another) at the point of intersection inside of a double layer. Any time Alfven found a double layer, he claimed it put another nail in the coffin of MR theory. MR theory will always be 'pseudoscience" because it's only every going to be "pseudo-correct". It's not however the magnetic lines that "reconnect", so it will never be "100% correct" as long as it has such a stupid name.
|
29th March 2011, 12:16 PM | #168 |
Illuminator
Join Date: May 2008
Posts: 3,197
|
No, neither of those do what you say.
Alfvén used a double layer to unwind a magnetic loop on the sun. Alfvén used an exploding double layer and said it was what happens in a flare, but arguments have been made that it will not come so far, for various reasons (see your own thread). Onel and Mann describe large e fields and use circuits. That has been discussed and has nothing to do with reconnection. Please give me the E orientation of magnetic reconnection (or should that be electric reconnection then ???). I asked that before and got a nonsense answer. But one can hope. michael2 should get something together. |
__________________
Scientific progress goes *BOINK* -- Calvin & Hobbes twitter: @tusenfem -- Super Duper Space Plasma Physicist |
|
29th March 2011, 12:17 PM | #169 |
Illuminator
Join Date: Mar 2008
Posts: 3,202
|
|
29th March 2011, 12:18 PM | #170 |
Graduate Poster
Join Date: Mar 2011
Posts: 1,565
|
[quote=Reality Check;7027611]
In the lab, they do not occur separately.
From what we know to be true about the laboratory proven physics of "reconnection" - the DL plays a role as a causative agent involved in the transfer of energy. Neglecting the existence of DLs by modeling reconnection events entirely in MHD frameworks does not mean they do not exist in real life. MHD theory is incapable of accounting for them, which is why they never pop up in discussions of reconnection. Given that we know localized instabilities will generate regions of varying voltage / potential, we know that there will be DLs formed. |
29th March 2011, 12:21 PM | #171 |
Illuminator
Join Date: May 2008
Posts: 3,197
|
That is just idiotic, MM.
Why on earth or in space or on the sun, would a current carrying plasma not be able to have magnetic reconnection? It is a frakking requirement of MHD or Maxwell's equations that if you have two regions with oppositely directed magnetic field that there is a current flowing, which facilitates the changing direction and magnitude of the magnetic field. So, when are you going to present us your circuit model of reconnection? I made a start for you in the other thread, but when you found that you actually had to do some real work, you suddenly gave up. Guess you can only write misconceptions about plasma physics, go figure. |
__________________
Scientific progress goes *BOINK* -- Calvin & Hobbes twitter: @tusenfem -- Super Duper Space Plasma Physicist |
|
29th March 2011, 12:23 PM | #172 |
Banned
Join Date: Feb 2008
Posts: 35,398
|
|
29th March 2011, 12:36 PM | #173 |
Graduate Poster
Join Date: Mar 2011
Posts: 1,565
|
The plasma expands primarily in the direction of ion flow:
http://plasma.physics.ucla.edu/web%2...rom%20Lab..pdf Toward the cathode. |
29th March 2011, 12:38 PM | #174 |
Illuminator
Join Date: May 2008
Posts: 3,197
|
|
__________________
Scientific progress goes *BOINK* -- Calvin & Hobbes twitter: @tusenfem -- Super Duper Space Plasma Physicist |
|
29th March 2011, 12:41 PM | #175 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 28,521
|
In the lab they do occur separately. There are many magnetic reconnection experiments.
In some experiments DLs are also detected, e.g. these 1982 and 1983 experiments Double layer formation during current sheet disruptions in a reconnection experiment N.B. AFAIK current sheet disruption happens after the magnetic reconnection event. Magnetic Field Line Reconnection Experiments, 5. Current Disruptions and Double Layers |
__________________
NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
|
29th March 2011, 12:51 PM | #176 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 28,521
|
It is certainly a strange reply. The paper turns out to be
Lessons from Labatory Experiments on Reconnection, R.L. Stenzel, W. Gekelman and J. M. Urrutia 1986 So he cites people who say that magnetic reconnection exists and worked with it a lot in the 1980s ! ETA: There is that double layers can be caused by current disruption. ETA2: And the paper that he cites proves that the current disruption and so the DL happens after the magnetic reconnection! |
__________________
NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
|
29th March 2011, 12:52 PM | #177 |
Graduate Poster
Join Date: Mar 2011
Posts: 1,565
|
The DLs are the mechanism that imparts kinetic energy to the particles.
As I stated earlier, what causes the instabilities in the current sheet is external to the sheet and a property of the circuit. You can have all sorts of instabilities without them resulting in the formation of a double layer. However, it is the formation of a double layer that drives 'reconnection'. An explosive release of energy can not occur without the onset of a DL. |
29th March 2011, 12:53 PM | #178 |
Graduate Poster
Join Date: Mar 2011
Posts: 1,565
|
|
29th March 2011, 02:17 PM | #179 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 28,521
|
That 1986 (see below about why I have this in bold) paper says nothing about what causes magnetic reconnection.
It states that magnetic reconnection exists and presumably the authors are capable of reading basic textbooks on electromagnetism and seeing that the cause is the reconfiguration of magnetic fields as allowed by Maxwell's laws. It says that after the magnetic reconnection there is current sheet disruption. That current sheet disruption can cause DLs. So I guess that you "agree to magnetic reconnection" . The point of the paper is that there is a regime in which the usual MHD concepts (e.g. Alfven waves and frozen-in magnetic fields) are violated and have to be replaced with other concepts such as Whistler waves. That is basically what Alfven said, i.e. the frozen-in magnetic field approximation was being applied to inappropriate regimes. That is why modern (2011) plasma physicists are careful to not apply the frozen-in magnetic field approximation inappropriately. In these regimes they use resistive MHD rather than ideal MHD. When the plasma is collisionless, they add in the Hall effect. |
__________________
NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
|
29th March 2011, 02:30 PM | #180 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 28,521
|
Repeating a wrong assertion does not make it true.
When there is just magnetic reconnection, magnetic reconnection is the mechanism that imparts kinetic energy to the particles. When there is magnetic reconnnetion + DLs then both mechanisms impart kinetic energy to the particles. The formation of the DLs happens after the magnetic reconnection. See Figure 9 in Lessons from Labatory Experiments on Reconnection, R.L. Stenzel, W. Gekelman and J. M. Urrutia 1986 ! Can you read it, michaelsuede? Can you see the disruption happening after the reconnection, michaelsuede? Can you understand the abstract where it stated that the double layers happen after the disruption, michaelsuede? |
__________________
NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
|
29th March 2011, 02:37 PM | #181 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 28,521
|
I will emphasis this one more time in case it is not clear to you, michaelsuede.
You cited Lessons from Labatory Experiments on Reconnection, R.L. Stenzel, W. Gekelman and J. M. Urrutia 1986 That paper proves that the order of events in their magnetic reconenction experiment was
That is as easy as 1, 2, 3 michaelsuede . |
__________________
NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
|
29th March 2011, 03:03 PM | #182 |
Banned
Join Date: Feb 2009
Posts: 9,361
|
|
29th March 2011, 03:13 PM | #183 |
Guest
Join Date: Jul 2006
Posts: 6,387
|
Aaaaaaaand we're off!
Does anyone participating in this thread have ANY reason to expect something different from http://www.internationalskeptics.com...120782&page=23 or http://www.internationalskeptics.com...193096&page=76 or http://www.internationalskeptics.com...107792&page=34 or http://www.internationalskeptics.com...147374&page=29 ? Or http://www.internationalskeptics.com...=113586&page=4 or http://www.internationalskeptics.com/forums /showthread.php?t=147365&page=4 or http://www.internationalskeptics.com...=138610&page=4 ? It's exactly, precisely the same thing again: a) The Alfvenites post the claim "reconnection doesn't work! Alfven said so. The explanation is double-layers and/or electric circuits." b) The other usual suspects point out that this is nonsense, and cite 40 years of mainstream plasma research in which reconnection makes perfect sense. c) The Alfvenites don't accept any of (b) as relevant or convincing, so they restate (a). Please don't do it again. There is no way it is going to end. There is no possible science statement, none whatsoever, that MM could understand well enough to interpret as contradicting his reconnection-is-wrong-somehow dogma. You could post a complete, analytic form for B(r,t), E(r,t), j(r,t), p(r,t), etc., that includes reconnection, show that it follows from Maxwell, and that wouldn't work either. Please, please, please, let this and all other "reconnection" threads die. The "I'm not trying to convince Michael, I'm doing it for other readers" argument doesn't work any more, not when we're on the 10th thread rehashing the same thing. Anyone who's still interested in reading can go read the old thread. |
29th March 2011, 03:32 PM | #184 |
Philosopher
Join Date: Oct 2009
Posts: 5,759
|
Actually, it was your fellow denier, michaelsuede, who implied Alfvén was an idiot in posts #144, #150, and #155.
Tubbythin asked for your views on michaelsuede's claims: You avoided Tubbythin's question by pretending he had asked about MR, not MHD. Don't think your tactic went unnoticed. Maybe michaelsuede can help you with that curl. The primary novelty of this thread is that our two deniers, michaelsuede and Michael Mozina, have gripped their argumentative swords with both hands and proceeded to hack off each other's legs. |
29th March 2011, 03:35 PM | #185 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 28,521
|
Wrong MM. Read the quote
Quote:
He never states that there is no physical situation where no electric current crosses the surface. He is saying that all of the MR theories in the 1980's were valid for when the perpendicular component of the curl is zero at every point of the surface (frozen-in magnetic field approximation?) and should not be used for other situations. Of course these is a little thing called science. Science progresses. MR theories improve. They are now valid for a wider regime. That is the danger, Michael Mozina, of relying on old textbooks - you get fooled by outdated science. As people have suggested several times - update your science library to at least get into the 21st century ! |
__________________
NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
|
29th March 2011, 05:22 PM | #186 |
Guest
Join Date: Jul 2006
Posts: 6,387
|
So what? The list of objections that bounce of MM is already pretty long. And it already includes "you're contradicting yourself", "you're contradicting Maxwell", "you're contradicting the 2nd Law of Thermodynamics", and "you're contradicting actual lab experiments". So now we can add "you're contradicting a fellow anti-reconnection crackpot" to the list?
|
29th March 2011, 06:01 PM | #187 |
Philosopher
Join Date: Oct 2009
Posts: 5,759
|
Bertrand Russell explains...
Originally Posted by Bertrand Russell
|
31st March 2011, 12:45 PM | #188 |
Banned
Join Date: Feb 2009
Posts: 9,361
|
I hate to break it to you, but it wasn't a 'tactic', I simply misread his question.
I would tend to 'disagree' with the claim that MHD theory is 'junk science' (assuming anyone actually said that).
Quote:
Quote:
From a mathematical perspective, yes you can approach it *EITHER* from a B or an E orientation, but it's actual the particles and circuits that 'reconnect', not the magnetic lines. Those 'lines' are produced by "current flow' and the "current flow" sustains both filaments and 'rate of flow' (of particles) across the double layer determines the rate of "reconnection"! They other obvious thing about all the so called "experiments' done to date is that NONE OF THEM actually tried to falsify the claim. They never explain what is physically unique and different from the kinetic energy particle transfers that Alfven describes in his double layer paper, or the transfer of photon kinetic energy to charged particles, *PROPERLY CALLED INDUCTION*. Instead they *ASSUME* things like the E field remained stable even while the thread size shrinks! The whole this is goofy. The particle reconnect. The current flows change direction. It's no mystery and no magnetic lines ever actually 'reconnect'. They just exist as a result of the current and their topology is directly related to the flow of that current as it changes over time. |
31st March 2011, 12:52 PM | #189 |
Banned
Join Date: Feb 2009
Posts: 9,361
|
Did I say reconnection didn't work or didn't happen?
Quote:
Quote:
Quote:
Quote:
|
31st March 2011, 01:13 PM | #190 |
Illuminator
Join Date: May 2008
Posts: 3,197
|
|
__________________
Scientific progress goes *BOINK* -- Calvin & Hobbes twitter: @tusenfem -- Super Duper Space Plasma Physicist |
|
31st March 2011, 01:27 PM | #191 |
Banned
Join Date: Feb 2009
Posts: 9,361
|
|
31st March 2011, 01:33 PM | #192 |
Banned
Join Date: Feb 2009
Posts: 9,361
|
How? I want to hear you *OR ANYONE ELSE* explain *EXACTLY* what makes "magnetic reconnection" a "new" and unique form of energy exchange. The transfer of particle kinetic energy to other particles of mass is not "magnetic reconnection", it's "particle collision/reconnection". The transfer of magnetic field energy to charged particles already has a proper scientific name, it's called *INDUCTION*. How did you or anyone else eliminate ordinary double layer processes like particle collision and induction from consideration before *LEAPING TO THE CONCLUSION* that "magnetic reconnection did it"? How did they eliminate ordinary induction and particle collisions as the real "cause/culprit' of particle acceleration?
|
31st March 2011, 01:37 PM | #193 |
Banned
Join Date: Aug 2007
Posts: 7,235
|
|
31st March 2011, 01:44 PM | #194 |
Banned
Join Date: Feb 2009
Posts: 9,361
|
Ya but don't forget that Alfven was an anti-reconnection crackpot too and *I'm* the one going at on a limb in terms of the merits of MR theory. Alfven simply rejected MR theory outright, calling it "pseudoscience" more than a dozen times in 1986 in front of a room for of plasma physicists. That's a pretty strong stance actually. I'm willing to concede that the B orientation is mathematically "ok", but why won't you cop to the fact that Alfven's method is also "acceptable"?
If I'm *FORCED TO CHOOSE* between Alfven's view and MR theory, forget MR theory. It's the most ridiculously named "theory" of all time and I thought the term "black hole" was misleading. |
31st March 2011, 01:47 PM | #195 |
Banned
Join Date: Feb 2009
Posts: 9,361
|
http://arxiv.org/abs/0908.0813
What are you waiting for, a engraved invitation to comment on Onel and Mann's work? |
31st March 2011, 02:00 PM | #196 |
Banned
Join Date: Aug 2007
Posts: 7,235
|
The question was regarding this discussion in this thread about this topic... And make your explanation quantitative and objective, please. Provide this induction and/or circuits explanation in a way that other people can understand, thoroughly, show the relevant math, and include proper citations to works, pages, and paragraphs. |
31st March 2011, 03:22 PM | #197 |
Muse
Join Date: Dec 2008
Posts: 969
|
Laboratory Magnetic Reconnection & Induction
Rubbish. Lest we forget, from 13 February 2009 ... So, Mr. Mozina, have you ever read any of the papers I cited here? No, you have not. Have you ever read any papers describing laboratory magnetic reconnection experiments? No, you have not. Have you ever examined the design & procedures of laboratory magnetic reconnection experiments? No, you have not. Have you ever examined the data coming out of any laboratory magnetic reconnection experiment? No, you have not. So, how the hell do you know what is really going on? "Particle reconnection" and "circuit reconnection" are buzzwords of your own invention which have no basis in physical reality. You have been asked to physically describe what they are supposed to mean on too many occasions to count, and have failed to do so every time. So I still have no idea what you think you are talking about. But I do know, beyond any shadow of a doubt, that it is the "reconnection" of the magnetic field and not the "reconnection" of anything else, especially the currents & particles, which is the source of energy. I know this because I know that the topology of the magnetic field changes first (we call that "cause") and the accelerated currents flow afterwards (we call that "effect"). Since cause precedes effect rather more often than effect precedes cause, magnetic reconnection is the obvious answer. This is why people do things called "experiments". I realize you have much disdain for such menial tasks and prefer to live a life of academic seclusion, but the rest of us have faith in the ability of the real world to actually show us what is really happening, if we just bother to look. You should bother someday yourself, you might actually learn something (perish the thought!). Have you ever examined the design & procedures of laboratory magnetic reconnection experiments? No, you have not. Have you ever examined the data coming out of any laboratory magnetic reconnection experiment? No, you have not. So, how the hell do you know what is really going on? No, as a matter of fact, it is not only not clear, it's not even possible because the like charges of the currents would repel each other, or are you now going to war against Coulomb too? And what about the magnetic fields generated by the currents in the filaments, which will surround the filaments in solenoidal shape? By what process do you suppose they might conveniently get out of the way and allow the bare naked currents to "reconnect"? Have you ever examined the design & procedures of laboratory magnetic reconnection experiments? No, you have not. Have you ever examined the data coming out of any laboratory magnetic reconnection experiment? No, you have not. So, how the hell do you know what is really going on? Sorry to but into this reverie with shocking facts, but there are these things called "measuring devices" in laboratories. They are used to measure things. Amongst the many things that can be measured are electric currents, electric fields and magnetic fields. So no, they do not assume that the electric field is constant, they measure the electric field, which cannot be constant and is not constant, because of Faraday's Law (or maybe now you are going to war against both Coulomb & Faraday?). They also measure the magnetic field and the electric currents. Funny thing is the magnetic field changes first (we call that "cause") and the electric currents change afterwards (we call that "effect"). How dare Mother Nature disagree with Mozina! Who does she thing she is, anyway? Of course they do. In fact, they always do. But since you can't read, you are hardly likely to realize this. however, for those who can read, and for the umpteenth time already since December 2009 ... Considering the "current" state of affairs, I must say I am impressed with the predictive power of the statement I made in those last few sentences from two years ago. And I boldly predict that, two years hence, the "current" state of affairs will remain unchanged. |
__________________
The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it. -- Bertrand Russell |
|
31st March 2011, 04:15 PM | #198 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 28,521
|
Nothing to do with Alfven.
That was michaelsuede's assertion that all magnetic reconnection is DLs. That is wrong beacuse: When there is just magnetic reconnection, magnetic reconnection is the mechanism that imparts kinetic energy to the particles. When there is magnetic reconnnetion + DLs then both mechanisms impart kinetic energy to the particles. The formation of the DLs happens after the magnetic reconnection. See Figure 9 in Lessons from Labatory Experiments on Reconnection, R.L. Stenzel, W. Gekelman and J. M. Urrutia 1986 ! Where do you think Alfven states that all magnetic reconnection is DLs? (Hint: it is not his 30 year old pseudoscience remark - that is about he inappropriate application of the frozen-in field approximation) |
__________________
NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
|
31st March 2011, 04:23 PM | #199 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 28,521
|
How is Maxwell's equations.
The ignorance continues (and the crackpot quoting and uppercasing !) Magnetic reconnection is not a new or unique form of energy exchange. Changes in magnetic field configurations impart energy to particles all of the time. Ask any particle physicist! The stupidity of calling magnetic reconnection has been pointed out many times before. The time scales make it impossible for induction to transfer the energy, And one more time for the simple minded (and I do mean you MM - you are obviously too simple minded to read or understand the many posts that have explained this to you. ): Induction was eliminated as a cause of particle acceleration because it takes too long, e.g. in solar flares it would take a million years to do it. |
__________________
NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
|
31st March 2011, 10:34 PM | #200 |
Illuminator
Join Date: May 2008
Posts: 3,197
|
Onel & Mann use a circuit model of structures on the sun, and then come up with the various values for the R and the U and everything else. Then they find the power in photospheric motion in Eq. 9 and show that in the circuit there is a total energy that is comparable with what is released in solar flares. One would be surprised if they had found something else.
Then they use runaway electrons that are accelerated at a coronal electric field, that lose energy through coulomb collisions Eqs. 11/12/13 and find a value for the Dreicer field, above which electrons are basically collisionless. Then basically, what they want to explain is the X-ray emission from flares, and find that the bremsstrahlung by accelerated electrons is the main cause and that electric fields, as described in their model, can explain the acceleration of the electrons. Fine, it is a nice paper (which I have said already some time ago), however, has nothing to do with magnetic reconnection. Nothing about how the magnetic field changes etc. Nice try, but no cigar. |
__________________
Scientific progress goes *BOINK* -- Calvin & Hobbes twitter: @tusenfem -- Super Duper Space Plasma Physicist |
|
Thread Tools | |
|
|