Magnetic Fields Dominate Young Stars of all Sizes?

by Anne Minard on June 11, 2009

Image courtesy of Manel Carrillo, Josep Miquel Girart (CSIC-IEEC), Nimesh Patel (SMA), Spitzer

When it comes to the role of magnetism in the formation of stars, size might not matter.

A team of researchers led by Josep Girart, of the Institut de Ciències de l’Espai (in Spain), studied the slow evolution of a dust cloud into a massive star, and realized that the cloud’s magnetic field controls the star’s development more than any other factor. They propose that the story is the same for small stars — an idea that could offer a new way to understand the formation of the early universe.

The new hypothesis is presented in this week’s issue of the journal Science, and the lead image represents an artist’s rendering of the concept.

The background shows a false-color Spitzer image of the massive star-forming region G31.41, with the colors indicating various wavelengths of light. The zoom-in region represents the dust emission from the massive hot core (color and contour image) superposed with bars showing the structure of the magnetic field.

Pictured in the bottom of the image is the Submillimeter Array in Hawaii, which was used for the observations.

The authors describe how the magnetic field at G31.41 has deformed the dust cloud into an hourglass shape – a telltale sign of magnetically controlled star formation.

They say that this magnetic energy dominates over the other energies at play — e.g., centrifugal force and turbulence — and suggest that the role of the magnetic field in the early stages of star formation could be very similar for both small and massive stars.

“The energetic relations do not differ too much” between massive and small stars, the authors write. “Both cores are collapsing because gravity has overcome pressure forces, but the collapsing dynamics are controlled by the magnetic energy rather than by turbulence.”

Girart and his colleagues point out that this only holds true for forming stars; older massive stars are more influenced by radiation and ionization pressure, turbulence, and outflows than by magnetic fields.

Massive stars play a crucial role in the production of heavy elements and in the evolution of the interstellar medium, so this discovery might eventually lead to new insights about the formation of the early universe.

Source: Science

DrFlimmer

@ Anaconda

DrFlimmer wrote: “The magnetic field does not have the structure of it, as I see it, so there is no possibility for it.”
The paper states that the magnetic field was in the shape of an “hourglass” which is as I state above the shape of a z-pinch.

AFAIU the wiki entries about the z-pinch, I concluded that they are able to deform things (like cans or wires) into an hourglass shape – not that the magnetic field itself has this shape. Normally the magnetic field “curves” around the current or the current flows along the magnetic field (and induces a curved magnetic field around itself). The articles never mentioned a magnetic field in the shape of an hourglass for a pinch – where do you have this from?

DrFlimmer, please explain your statement: “It could also be a time-dependent electric field.”

Time-dependent means that the value of a thing is not constant over time. E.g. the electric field strength can vary with time. A simpler example is probably a car. If the velocity is not zero the car changes its position with time – so the position is time-dependent.
In more mathematical description this means that the derivative with respect to time does not vanish. In the case of the car this is: dx/dt=v, where x is the position of the car, d/dt is the derivative wrt time and v is the non-vanishing velocity of the car. If the car stops, it does not change its position anymore and hence dx/dt=0.
So a time-dependent electric field means that its derivative wrt time does not vanish. Even more it is explicitly time-dependent and hence changing with time.
The implication for the Maxwell equation is that you can have a magnetic field, although there could be no current!

DrFlimmer wrote: “You can see a magnetic field but probably the cause is ‘far away’.”
How far away and under what circumstances?
And what is the basis/authority for your assertion, “probably” far away?

Nereid2 wrote a wonderful answer that I didn’t think of. I was about to talk about a straight wire with a current and the magnetic field that surrounds it. If you do the math (Biot-Savart law) you would find that the magnetic field drops inversely with the distance from the wire – so it would drop to zero at an infinite distance. Being a little closer than infinity from the wire ( ) would mean you could measure a magnetic field – but the underlying current is probably VERY far away and it could be hard, just from the measurement of the field strength, where the current is and how strong it is! It could be weak and nearby – or strong and far away.
To add something to Nereid2’s example: Take a look at Jupiter’s magnetic field. It reaches out to the orbit of Saturn which is about twice the distance from the sun than Jupiter. This is quite a distance!

After all, Science knows that magnetic fields spiral AROUND electric currents in the form of the ‘right hand rule’.

If there is a current: Yes. But how is should a current look like that produces a magnetic field that looks like an hourglass?

I understand you may have access to the full text of the paper. If so, do the authors report whether they attempted observation & measurement of synchrotron radiation? And if they did make the attempt, did they detect any?
Peratt, Astrophysics and Space Science (1995) states that synchrotron radiation emission should be detected from pinched particle beams: “Z-pinches are among the most prolific radiators of synchrotron radiation known. In this regard, the Bennett-pinch, or Z-pinch, as a synchrotron source has been treated by Meierovich (1984) and Newberger (1984).”
[link omitted]
The detection or non-detection of synchrotron radiation would shed evidentiary light on whether the “hourglass” shape observed & measured in the present paper is a result of a Z-pinch.

If you want to have the paper, too, then send an email to the address I posted above.

So, now, let’s talk a little bit about the paper. I will quote a few passages that I find interesting and comment on them as far as I can (some equations are modified in order to be readable; numbers in brackets, e.g. (14,15), are references).

[…] suggesting that the core’s center harbors O-type hydrogen-burning stars (14, 15). It is associated with very weak free-free emission (16), implying that an ultracompact HII region has not yet developed and therefore that the embedded young stellar objects are in a very early stage of their evolution.

This is the only passage in the paper where the authors talk about free-free emission. This emission could be synchrotron radiation, but bremsstrahlung is also a possible mechanism. That this emission is very weak seems to indicate that the underlying mechanism is not very effective and thus the source is very weak.

The 4 GHz of bandwidth available for the SMA allowed us to detect a large number of spectral lines. The myriad of lines is dominated by CH3OH, with more than 30 lines, but also by HCOOCH3, CH3OCH3, and SO2.

There are huge and high numbers of molecules in the cloud. I think this means that at least the envelope of the new-forming star is not very ionized.

One of the lowest excitation lines, C34S 7-6, shows a clear inverse P-Cygni profile in its spectrum

This means that the envelope is collapsing and hence the star is accreting.

We proceeded, similarly to (11), to derive the magnetic field properties by first fitting its morphology with a family of exponential functions. We find that the center of symmetry of the magnetic field coincides within the measured uncertainty, ~0.2”, with the center of the core (i.e., the position of the dust emission peak).

I have spoken about this point in a previous post. I think this indicates that the collapsing cloud took the magnetic field with it. As I see it, a mechanism like this would result in an hourglass shape for the magnetic field.

The magnetic field strength can be estimated from the dispersion in polarization angles (which is a consequence of the perturbation by Alfvén waves or turbulence in the field lines). With use of the value of the volume density derived from our data, n(H2) = 3.1 × 10^6 cm^?3, and a turbulent velocity dispersion of dvlos ? 2.7 km s^–1, the expected value from the Osorio et al. modeling (14) at the scale of ?1.5 × 10^4 AU, which is the scale of the observed polarized emission—we calculated the magnetic field strength in the plane of the sky to be B_pos ? 9.7 d_(7.9)^(–1/2) mG.

Here “d_(7.9)” is the distance to the object in kpc – which is a number with some uncertainties, so the values of the magnetic field (and some other values in the paper) are normalized with the distance. One of the important things is that the magnetic field can only be measured in the “plane of the sky”. There is a lack of information about the 3rd dimension. This is the point which makes it impossible to calculate any underlying current, since Maxwell’s equations are strictly three dimensional. If one is missing (as is the case here) there is no chance to calculate anything.

The mass accretion rate can be estimated from the infall velocity derived from the inverse P-Cygni profile.
[…]
Following Beltrán et al. (26), the mass accretion rate onto the star (4*pi*R^2*m(H_2)*n*V_(infall)) inside a solid angle “Omega” is M_acc = Omega/(4*pi)(3 × 10^?3 to 3 × 10^?2) M_sol year^(?1), which is in agreement with the estimate from modeling G31.41 (14). Such a high value of the infall rate has also been estimated for other O-type (proto)stars (26–28), supporting the non-spherical accretion scenario for the formation of massive stars, which is expected in the presence of a substantial magnetic field, as observed here.

I think no further comments are necessary for this point.

For a collapsing core with angular momentum conservation and with a very weak magnetic field, the rotation velocity is expected to be inversely proportional to the radius (10). This is the opposite of what is observed in the HMC, in which the rotation velocity decreases for decreasing radius, indicating that the angular momentum is not conserved during the collapse. Given the hourglass magnetic field morphology in the HMC, this spin-down in the HMC suggests magnetic braking, a process proposed to remove the excess of angular momentum. Theoretical models of magnetic braking predict a spin-down qualitatively in agreement with what is shown in Fig. 4 (7, 10).

This also needs no further commenting. Finally I want to quote the whole last paragraph, which also speaks for itself:

The HMC in G31.41 is much larger (by a factor of 20) and more massive (by a factor of 200) and luminous (by five orders of magnitudes) than the Sun-like IRAS 4A. However, both sources show an inverse P-Cygni profile, indicative of infall motions (30), and have similar magnetic field properties (a hourglass configuration approximately along the major axis and a similar mass-to-flux ratio). The energetic relations do not differ too much, either: Both cores are collapsing because gravity has overcome pressure forces, but the collapsing dynamics are controlled by the magnetic energy rather than by turbulence. This similarity suggests that the role of the magnetic field in the early stages of the formation of high- and low-mass stars may not be too different. However, once the massive stars turn on an ultracompact HII, the feedback from the massive stars (radiation and ionization pressure, turbulence, and outflows) becomes energetically more important than the magnetic fields (31).

As I said, if someone is interested in the paper, send me an email! The paper is only 4 pages long, so reading takes only a short amount of time
ND

Some additional evidence that no matter how much effort you put into trying to explain things to Anaconda. You’re not going to get anywhere because he will not be able to advance beyond his insanely limited understanding of scientific concepts he talks about.

thunderbolts.info/forum/phpBB3/viewtopic.php?f=3&t=1870&p=22075#p22075
Nereid2

@ND: one thing that several people have noted, in various fora, is that proponents of EU ideas seem to act as if the essential core of science (or at least astronomy) is something like ‘if it looks like a duck, it is a duck’ … i.e. the ultimate validation of a hypothesis is finding an image which has features that match artistic representations loosely based on that hypothesis …

… and it matters not one bit how the image was created, what the image is ‘of’, what its scale is, and so on.

(Anaconda’s ‘hourglass shape’ is a good example here; he clearly doesn’t understand *what* has this shape, but as it is the same – at the word level – as that of Z-pinches, it *is* “A magnetic Z-pinch as directly observed & measured in this post“! Another example is his ‘here are radio images of SgrA, they don’t *look* at all like a black hole’ … if we take this at face value, his complete blindness to the *scale* left me gobsmacked).

I came across a passage in a book I’m reading that may shed some light on this, relating to some core characteristics of science … I’ll copy them here later …
IVAN3MAN

@ Nereid,

Hey, did you know that mgmirkin is a moderator on the Thunderbollocks Forum?
ND

Nereid2,

It’s both infuriating and fascinating at the same time. It’s like a novel you can’t put down, in a wierd sort of way.

It’s not just looks-like-a-duck, but also “it’s going to be currents in space, you’ll see, just wait and you’ll see”. And this in complete contradiction with the how-science-is-done lecturing we hear. Anaconda has got the rhetoric down, but not the deeper understanding of the theories and concepts. He also looses his cool at times and gets very upset. I don’t understand why. It’s just sunspots and aurora!

When I showed Anaconda gravitational simulations of galaxy collisions that looked remarkably like what we see, he was rather silent.

It’s definitely been fun and an opportunity to learn and dig deeper into various topics that Anaconda gallops through.
Anaconda

@Nereid:

I normally do click links, but your statement suggested it was about “giving credit where credit is do” and since I agree with you, I didn’t want to hash through a forum thread.

Nereid wrote: “Thornhill’s ideas, as presented in that document are not so much wrong, scientifically, as meaningless.”

Yes, you address the merits in your typical pedantic way. I disagree with you and there were others on the forum thread who did as well.

You obviously had a “thing” against Plasma Cosmology long before I got here.

It’s off topic, so I’ll address it if an appropriate post comes along.

Nereid presents a quote from the instant paper: “The HMC is simultaneously contracting and rotating, and the magnetic field lines threading the HMC are deformed along its major axis, acquiring an hourglass shape.”

I’m fine with that, and go with the actual words in the paper (except for “lines”, field “lines” are a conceptual aid, a magnetic field is an undifferentiated continuum of magnetic strength, there are no actual “lines”).

“contracting and rotating”, this is consistent with a magnetic field acting around an electric current, remember the right hand rule.

Nereid, it’s clear from everything I’ve seen, your mind is closed and you’re a pseudo-sceptic.

Nereid, I show as much respect as I’m shown and frankly you disagree and dodge questions on evident points, divert the questions often into the weeds, and express raw contempt, so i’m not likely to sign up for your advice.

You want to go hemispheric and rehash, no, I’ll stay on topic.

DrFlimmer: “The implication for the Maxwell equation is that you can have a magnetic field, although there could be no current!”

No.

Your analogy is false because a car at rest is still a car, but an electric current at rest is not an electric current. An electric current is only a current with electrons in motion, without electrons in motion their is no magnetic field.

Wherever you got that analogy gave you a bum steer.

DrFlimmer wrote: “Being a little closer than infinity from the wire ( ) would mean you could measure a magnetic field – but the underlying current is probably VERY far away and it could be hard, just from the measurement of the field strength, where the current is and how strong it is! ”

No.

You are ignoring the paper’s language and magnetic compression. The physical constriction requires the magnetic field to surround the object and the magnetic field surrounds the current.

Another piece of faulty logic.

DrFlimmer wrote: “It reaches out to the orbit of Saturn which is about twice the distance from the sun than Jupiter. This is quite a distance! ”

But it doesn’t exhibit a constricting and rotating ability. It stretches out the same way the Earth magnetosphere does, but it does’t constrict.

Your logic is unhinged from the object in the instant paper. DrFlimmer keep an open-mind, not this attitude Nereid and the others display — you’ll be much better off.

DrFlimmer wrote: “This means that the envelope is collapsing and hence the star is accreting.”

Magnetic fields compress matter from the outside, not collapse it from the inside via a pull mechanism — that is what is remarkable about the paper.

Okay, we don’t have enough data to know if there is synchrotron radiation.

The instant paper stated: “We proceeded, similarly to (11), to derive the magnetic field properties by first fitting its morphology…”

So, the shape, “morphology”, of an “hourglass” is important to their analysis.

DrFlimmer wrote: “I have spoken about this point in a previous post. I think this indicates that the collapsing cloud took the magnetic field with it.”

No.

The magnetic field is constricting on the plasma/neutral matter (as the magnetic field constricts the current density increases and temperature rises and a greater degree of ionization is likely achieved).

Read the paper, the magnetic field is acting on the matter not the other way round.

Magnetic fields constrict because of increased current density, this is the Z-pinch effect, a self-reinforcing mechanism (self-reinforcing mechanisms or positive feedback is often seen in electrical dynamics.

DrFlimmer wrote: “This is the point which makes it impossible to calculate any underlying current, since Maxwell’s equations are strictly three dimensional. If one is missing (as is the case here) there is no chance to calculate anything.”

Okay, but an inability to measure does not mean an electric current doesn’t exist, it just means current techniques aren’t able to measure it.

The instant paper stated: “Given the hourglass magnetic field morphology in the HMC, this spin-down in the HMC suggests magnetic braking, a process proposed to remove the excess of angular momentum. Theoretical models of magnetic braking predict a spin-down qualitatively in agreement with what is shown in Fig. 4 (7, 10).”

Actually, electromagnetic effects are known to dissipate angular momentum. So if the paper’s authors would have considered electromagnetic processes they would not have had to invoked a speculative idea, such as “magnetic braking”. This is another concept the gravity “only” model has had to invoke because it does not consider electromagnetism.

Since it’s not apparent whether synchrotron radiation was detected or not. It seems a reasonable follow up to this paper would be to bring to bear instrumentation on this object that can detect synchrotron radiation at a high level of sensitivity and observe & measure whether there is such synchrotron radiation.

If there is synchrotron radiation it adds weight to the electric current/magnetic field, Z-pinch hypothesis, if there isn’t then it goes a long way to falsifying the hypothesis.

I understand Science has the detector instruments to be able to do this now.
Nereid2

@Anaconda: this last comment of yours reads like a garbled message from some alternate universe …

I thought I’d lost an ability to be dumbstruck by how appallingly ignorant (and proud of it) your comments could be … but I was wrong, this last one really does raise delusion to a new level.

I mean have you ever actually *read* a paper by Alfvén (say)? Did you understand *anything* in such a paper other than some simple words like ‘move’?

OK, OK, let’s take a really, really, really simple step, shall we, to trying to talk with words that we mutually understand?

Since it’s not apparent whether synchrotron radiation was detected or not. It seems a reasonable follow up to this paper would be to bring to bear instrumentation on this object that can detect synchrotron radiation at a high level of sensitivity and observe & measure whether there is such synchrotron radiation.

Let’s be charitable and assume that this was meant to be one sentence.

Let’s stay focussed on this and see if we can get to a point where you express what you intend to say in a way that makes any kind of sense, within the framework of classical electromagnetism and its extensions to incorporate the fact that charges are quantised.

What – in your own words – do you think “synchrotron radiation” is?

What – in your own words – do you think its observational signature would, or could, be wrt objects, or sources, outside the solar system?

What do you think would be suitable “instrumentation” that could be used to “observe & measure” such radiation?

Leave aside, for now at least, any thoughts about z-pinches, ultracompact HII objects, the HMC, etc, etc, etc, and focus on synchrotron radiation.
Nereid2

@ND: it sure is!

Look at this latest comment by Anaconda for example, the level of self-delusion is breath-taking!

I mean, despite all the effort that so many people have put in, over many months, to try to help him understand the basics of classical electromagnetism, he writes such unintelligible gibberish, with the features and attributes of someone who actually thinks they understand what any of this means.

Worse, he clearly thinks he has a deep insight into the way the universe works, certainly an insight he considers to be far superior to that of Girart et al. … despite the obvious fact that he has not understood anything important about what’s actually in the paper, and doesn’t understand the very physics he so volubly proclaims is at the heart of his insight!!

Tomorrow I will find time to copy the passage from this book I’m reading; I think you’ll find it quite interesting …
Anaconda

Ah…the static…the flak. Must be over the target.

Since it’s not apparent whether synchrotron radiation was detected or not, it seems a reasonable follow up to this paper would be to bring to bear instrumentation on this object that can detect synchrotron radiation at a high level of sensitivity and observe & measure whether there is such synchrotron radiation.

A straightforward proposition, but some just want to put their hands over their ears, and chant, “I can’t hear you.”

Synchrotron radiation is a type of electromagnetic radiation that can be emitted over different parts of the electromagnetic wave spectrum. It is a product of ultrarelativistic (i.e., moving near the speed of light) electrons spiralling around a magnetic field. A couple of its characteristics are non-thermal radiation and polarization.

It was predicted to exist in space by Hannes Alfven, 1970 Nobel Prize winner, and his associate in 1950, six years before it was actually detected by 1956 by Geoffrey R. Burbidge.

It can be detected by astromomical instruments and has been for over 60 years.

But as usual Nereid wants to distract from the relevant issue. Synchrotron radiation is a signature of Z-pinches and it CAN be detected, but apparently it wasn’t determined if present in this paper.

Subsequent follow up investigation should be carried out to determine whether syanchrotron radiation is present or not.

A reasonable suggestion to investigation given the evidence already in hand, but that’s not what Nereid wants to hear.

Too, Bad.
Nereid2

If you’d like to learn more, and see how this is applied to plasmas, I can suggest an online university course in plasma physics

That’s me; how did Anaconda respond?

Here’s how:

Nereid, I show as much respect as I’m shown and frankly you disagree and dodge questions on evident points, divert the questions often into the weeds, and express raw contempt, so i’m not likely to sign up for your advice.

(bold added)

In case any other reader would be interested, Richard Fitzpatrick, of the The University of Texas at Austin, has a graduate course online entitled “Introduction to Plasma Physics“, and it can be found here:
http://farside.ph.utexas.edu/teaching/plasma/lectures/
Nereid2

Someone may have asked this of Anaconda before, but I don’t recall the answer and I’m curious to know …

DrFlimmer, please explain your statement: “It could also be a time-dependent electric field.”

That’s Anaconda’s question, about Maxwell’s equations, and it’s a good one.

Here’s DrFlimmer’s full reply:

Time-dependent means that the value of a thing is not constant over time. E.g. the electric field strength can vary with time. A simpler example is probably a car. If the velocity is not zero the car changes its position with time – so the position is time-dependent.

In more mathematical description this means that the derivative with respect to time does not vanish. In the case of the car this is: dx/dt=v, where x is the position of the car, d/dt is the derivative wrt time and v is the non-vanishing velocity of the car. If the car stops, it does not change its position anymore and hence dx/dt=0.

So a time-dependent electric field means that its derivative wrt time does not vanish. Even more it is explicitly time-dependent and hence changing with time.

The implication for the Maxwell equation is that you can have a magnetic field, although there could be no current!

Now keep in mind that Anaconda doesn’t understand Maxwell’s equations … he can’t, because he doesn’t have the required grasp of the math that underpins it.

Also keep in mind that the topic is Maxwell’s equations, in general.

Here’s how Anaconda responded:

DrFlimmer: “The implication for the Maxwell equation is that you can have a magnetic field, although there could be no current!”

No.

Your analogy is false because a car at rest is still a car, but an electric current at rest is not an electric current. An electric current is only a current with electrons in motion, without electrons in motion their is no magnetic field.

Wherever you got that analogy gave you a bum steer.

(bold added)

Given that you don’t understand Maxwell’s equations, Anaconda, how did you conclude that DrFlimmer is wrong?

Specifically, what is the basis for your certainty that “without electrons in motion their is no magnetic field“?

Let’s take light.

Light is, I think you’ll agree, electromagnetic radiation. Now in standard textbooks on electromagnetism, you’ll find a derivation of light as an electromagnetic wave, from Maxwell’s equations (I can’t explain the derivation to you because the math is far beyond what you can grasp, today).

Specifically, light (or any electromagnetic radiation) is a time-varying electric field that is orthogonal to a time-varying magnetic field; one creates the other in a mutually dependent way*.

There is no electric current, yet there is a magnetic field.

There is, as DrFlimmer said, a time varying electric field, and it creates a magnetic field.

Perhaps you can grok this by asking yourself this question: where are the “electrons in motion” associated with the magnetic fields in light?

*note to those who know this stuff: if you know a better way to explain this to someone who is obviously entranced by electromagnetism but whose math skills don’t even include simple calculus, please jump in!
Nereid2

Let’s recap how we got to where we are now …

I am particularly interested in discussing the material on redshift … where do you suggest that I – or any other reader with a similar interest – go to have such a discussion?

That’s me; I’m following up on this, from Anaconda:

I appreciate your request for peer-reviewed papers, that is reasonable and I appreciate your acknowledgement of solrey’s offering.

In an attempt to further that request I offer the following link:

[URL omitted]

The link lists a series of terms and topics related to Plasma Cosmology, click the term or topic wanted and it will present an article — at the bottom of each article is a bibliography of footnoted documentation each article used.

The footnotes state whether it is a peer-reviewed paper, a textbook, or generally what is the footnote’s provenance. (Yes, there are some papers and sources that aren’t peer-reviewed. Again, somewhat like a professor’s library shelf.)

It also states whether it is the full text or an abstract. Not all footnotes are linked, but most are.

I think you will find that each article is copiously footnoted with the footnotes at the bottom of the screen page of each article.

OK so far, right? A request (from JonH) for peer-reviewed papers, a good reply from Anaconda, and a follow-up by me.

Here’s what happened next:

Let’s take one example, and let’s make it a threshold question: Are there electric currents in space plasma?

Let’s take the entry off the list of articles entitled, “Electric currents in space plasmas”, see link below:

[URL omitted]

I note in the bibliography there are 22 peer-reviewed papers. To break that down, there are 15 peer-reviewed papers in the footnote section and there are 7 peer-reviewed papers in the general reference section.

OK, not a straight answer to my question, but an interesting topic (“Electric currents in space plasmas”), and an apparent promise that there are peer-reviewed papers on it.

Things start to go awry soon after though.

The webpage in the link talks about electric currents in several kinds of space plasma, one of them is the interstellar medium, and it is reasonable to start digging into Anaconda’s sources systematically; besides, it’s the ISM that I have the most familiarity with (and the greatest interest in).

Applying an Anaconda criterion, from other UT story comments (I’ll dig up the original if anyone is interested), and restricting ourselves, for now, to regions of space outside the solar system and specifically to the ISM (interstellar medium), we can ask of the referenced peer-reviewed papers “what observational evidence is presented for the existence of electric currents in space plamas?”

[...]

Now I think there are only three peer-reviewed papers of relevance to this question, 12, 13, and 16.

I acknowledge, upfront and openly, that I may have missed something (Anaconda, please point out what I may have missed in any of these three papers), but there is no observational evidence for the existence of currents in (ISM) space plasmas!

I don’t know about you, but in this kind of situation I’d've expected a response along the lines of

“Good point Nereid2. As I said earlier, I’ve not actually read any of those three papers, so I’ll download them, read them, and get back to you.”

or perhaps

“Good to see that you’re taking the trouble to try to learn about this Nereid2; however, you did miss something: you see in {paper}, in section {X}, …”

or even

“That’s right, none of those three papers do present any observational evidence for the existence of currents in (ISM) space plasmas. However, in this subsequent paper, which cites {one of the three}, {author} reports {summary of observations}.”

Did Anaconda respond with something like this?

No; here’s his response:

Nereid wrote: “…but there is no observational evidence for the existence of currents in (ISM) space plasmas!”

Wrong.

A magnetic Z-pinch as directly observed & measured in this post only happens because there is electric current through the plasma.

Also, because of the validity of Maxwell’s equations, Science knows that the detection of magnetic fields requires the presence of electric currents.

And it went downhill from there (Girart et al. did not report the direct observation and measurement of any “z-pinch” (they didn’t even use the term!), such a direct observation is impossible anyway (per Maxwell’s equations and current astronomical techniques), and Anaconda’s personal interpretation of Maxwell’s equations is wrong).

So, I’ll make this effort to get back on track: what observational evidence is there, Anaconda, of currents in (ISM) space plasmas, as reported in papers published in relevant peer-reviewed journals?

Specifically, did I miss any such evidence in the three papers referenced on the webpage you provided a link to? If so, what?
Nereid2

Why is it important to note the dates of publication of the peer-reviewed papers referenced in the resource website Anaconda provided a link to?

Nereid wrote: “The year of publication of the papers is (some years have more than one paper): 2005, 2002, 2001, 1997, 1992, 1990, 1988, 1983, 1978, 1969, 1967, and 1942.

For the references (same caveat): 1967, 1988, 1990, 1996, and undated.”

So?

That doesn’t dispute their scientific validity.

It seems that’s just another avoidance technique, rather than just acknowledging electric currents to exist in space plasma.

There are many reasons, but the one I am focussed on now relates directly to something that both Anaconda and I seem to agree on; namely, observational evidence.

I have asked whether any EU/PC proponent can provide the outline of a method of analysing astronomical data (observations) that would permit ‘electric currents in space plasmas’ to be robustly estimated (i.e. 3D representation of both magnitude and direction). I do not think it can be done, in general, and even in very special circumstances is likely to be extremely challenging.

Why? Well, Maxwell’s equations combined with the ’2D’ constraints of astronomical observations combined with the fundamental constraints of remote sensing.

As I expected, no EU/PC proponent has been able to provide such an outline.

Further, their inability to do so has a solid foundation, in the form of a paper (papers actually) by someone all such proponents respect … Hannes Alfvén.

Even more striking is that the inability of remote sensing to robustly and unambiguously infer, or characterise, ‘electric currents in space plasmas’ is described in some detail in references on the very webpage Anaconda cites (do you know which ones, Anaconda?).

The closest space plasma to us here on Earth is the Earth’s magnetosphere; no surprise to learn that it has been studied extensively, and even in situ. What has been discovered is both fascinating and astonishing, and, among other things, provides confirmation in the form of dozens and dozens of peer-reviewed papers that electric currents in space plasmas cannot be characterised by remote sensing.

Perhaps the most imporant discoveries – about electric currents in the Earth’s magnetosphere (including the interface with the solar wind) – have come from Cluster/Double Star and from THEMIS.

The Cluster mission took its first scientific data in early 2001, and THEMIS in 2007; the scientific data from these mission has resulted in a great many published papers.

Now comes the part where you, dear reader, need to be sitting down … not a single one of these papers is referenced on the ‘Electric currents in space plasmas’ webpage!

So no, Anaconda, the date of publication of a paper does not, in and of itself, “dispute their scientific validity“; however, when dozens, perhaps hundreds, of later papers are not mentioned – papers which contain the results of in situ studies of these very currents (or lack of them) – my curiosity is piqued.

It gets even more curious.

References 14 and 15 are Press Releases (PR), on THEMIS findings (so iantresman certainly was actively working on the content of this page at the time), unlike most other references. There are dozens of published papers, based on THEMIS results, many of them available around the time of the PRs cited … yet not a single one is cited!

Why?

I think I know what’s going on here, but I would welcome others’ comments – and especially Anaconda’s – before I comment further.
Nereid2

Forgot to add: if anyone is interested, I will provide links to webpages with THEMIS and Cluster/Double Star publications.
Nereid2

It’s not just looks-like-a-duck, but also “it’s going to be currents in space, you’ll see, just wait and you’ll see”. And this in complete contradiction with the how-science-is-done lecturing we hear. Anaconda has got the rhetoric down, but not the deeper understanding of the theories and concepts.

(bold added)

I don’t think it necessary to walk readers through the ‘Thornhill’s intellectually fraudulent document on comets’ set of comments, to illustrate ND’s point about Anaconda’s rhetoric, but there is one part of Anaconda’s final comment on the matter (for now anyway) that I’d like to discuss

Yes, you address the merits in your typical pedantic way.

Anaconda obviously means this in a negative way (subtext: being pedantic is *bad*).

Yet consider this: what is at the heart of the scientific method if not ‘be pedantic, systematically’?

Do you, Anaconda, have a version of doing science in which being pedantic is bad?
Nereid2

Solrey’s attribution was not quite right; the text of the quote is to be found in “Birkeland, Kr. : 1908, 1913 The Norwegian Aurora Polaris Expedition 1902-1903, Christiana, Norway, Aschehoug, Secs. 1 and 2″

That Birkeland quote is from a lecture given in 1908 while he was a professor at the University of Oslo, I believe.

I don’t have my copy of that document to hand now, but I’ll check it out when I do, and comment on how faithful it is, and, more important, the extent to which it establishes the point solrey was trying to make.
Nereid2

As promised, the extract from a book I’ve just finished reading (source, and further comments, below)

To research this chapter, I did something that I had never done before: I visited some Web sites representing creationism in its many guises. This exercise was a revelation indeed, but probably not of the sort that Webmasters had intended. What I found most striking was the appalling lack of integrity of those concerned. The deliberate misuse of quotations and details from the work of scientists suggested that all honor and honesty had been cast to the four winds. I realized that I was in a different social context from the one I have known and loved for my whole scientific career, where an honest search for the truth is at the heart of things. Instead, I was in a milieu where the dominant ethos was to force acceptance of a particular worldview by any means whatever.

[…]

What makes the scientist’s naturalistic view of the universe any better than its divine-interventionist counterparts? Well, precisely this. Most of those who hold the naturalistic view do so in a tentative way. The English evolutionary biologist John Maynard Smith put it memorably when he said that, unlike a creationist, he was prepared to abandon his stance if he were to find strong evidence against it.

[…]

It is precisely this tentativeness, and a willingness to consider the possibility of evidence contrary to one’s worldview, that is lacking from the stance of creationists. Their writings reveal quite the opposite: a false certainty, and a desire to distort any evidence so that it appears to support them.

Source: Wallace Arthur, “Creatures of Accident” (2006) pp226-227

Now what does the comments of a biologist (zoologist actually) about creationism have to do with EU/PC ideas?

Well, I think it’s fair to say that many scientists and disinterested observers have much the same reaction as Arthur’s upon encountering material by EU/PC proponents; the similarities between creationists and EU/PC proponents are striking.

Here, for example, are some extracts from Tom Bridgman’s blog, “Dealing with creationism in astronomy“:

My list of similarities between EU and creationism has grown significantly, largely thanks to this post from Mr. Smith.

[...]

My original posts were responses to earlier similar queries. It appears that Mr. Smith now wants to avoid my responses by claiming that those issues are no longer important. Now it is these additional topics that I must address. This overloading of topics is also a popular creationist debate tactic, a variant of the “Gish Gallop”.

[...]

EU wants us to talk about the currents, but we don’t directly detect the currents. We can directly detect magnetic fields or radiation from electrons accelerating in fields, and to a lesser extent, electric fields. [...]

Another fallacy that Mr. Smith makes here is the assumption that any problem in the standard model cosmology automatically favors the EU model. Many creationists use this same argument, also utilizing many of the same ‘problems’ in mainstream cosmology as evidence in favor of their interpretation of cosmology.

[...]

Am I interested in the EU stellar model?

Which model would that be? A claimed scientific model composed of nothing but cartoons, hand-waving explanations but nothing that comes close to the physical and mathematical rigor of any scientific model that makes even reasonable predictions. Those predictions are needed to explain a pheonomenon or build a technology. Mr. Smith accuses me of ‘hand-waving’, but it is EU models’ lack detailed predictions that we can test against real measurements which is the definition of ‘hand-waving arguments’ in science.

Source:
http://dealingwithcreationisminastronomy.blogspot.com/2009_05_01_archive.html

(to be continued)
Nereid2

(continued)

I found this on the JREF Forum, while googling for material on electric currents in space plasmas. It seems this UT story is not the only place on the internet where EU proponents are hawking the Girart et al. PR as iron-clad evidence of a z-pinch!

Sol88: … this “new” finding confirms the EU understanding that they (stars) form in a Bennett pinch and are powered by Birkeland currents (FAC’s), taking on a classic “hourgalss” shape along with broadband radiation and filamentry structure on the extremites!

Tim Thompson: That’s a complete fairy tale. At best it allows you to argue that an EU scenario is plausible, but only on a very general, heuristic level. But it certainly does not “confirm” the EU hypothesis for the very simple reason that there is no EU hypothesis to confirm.

One thing you will notice that is common to all EU arguments ever presented anywhere, in books or on websites or anywhere else, is that they are never specific about anything. There is a reason for this. As long as you don’t say anything specific then nobody can pin you down.

So, for instance, exactly why would any kind of plasma pinch give an “hour glass” shape? And more importantly, how do you get a pinch to sit around and keep on pinching for zillions of years? What specific field strengths and current densities allow for this? and where does all that charge separation come from? After all, you need an electric field to separate charges, but you need to separate charges to get an electric field. So which one is the “chicken” and which one is the “egg”? We never get specific answers to specific questions. Hence, there is in reality no EU hypothesis to defend.

(some formatting in the original is lost in this copy)

Source:
http://forums.randi.org/showthread.php?p=4827154#post4827154
DrFlimmer

@ Anaconda

Nereid2 already said some words, but I am so bold to answer for myself.

DrFlimmer: “The implication for the Maxwell equation is that you can have a magnetic field, although there could be no current!”
No.
Your analogy is false because a car at rest is still a car, but an electric current at rest is not an electric current. An electric current is only a current with electrons in motion, without electrons in motion their is no magnetic field.
Wherever you got that analogy gave you a bum steer.

That analogy was not intended to be an analogy for the electric current but rather for what it means to be “time-dependent”. I thought that was clear, but obviously it was not. Whatever, my explanation of the Maxwell equation still holds: You can have a magnetic field without having a current. That is fact! And this fact was introduced by Maxwell to correct Ampère’s law which had some flaws with experiments. The term with the time-dependent electric field is called “Maxwell’s displacement current”, but it is not a current in the normal sense.
Oh, and btw. According to special relativity it is possible to transform oneself into the system of rest of the current, hence in this system there is no current and no magnetic field – but in other systems you have a magnetic field. This in turn leads to the interpretation that magnetic and electric fields are just two sides of the same coin. But this another story and to explain you this, I need more than simple calculus, what even a school boy should understand.

DrFlimmer wrote: “Being a little closer than infinity from the wire ( ) would mean you could measure a magnetic field – but the underlying current is probably VERY far away and it could be hard, just from the measurement of the field strength, where the current is and how strong it is! ”
No.
You are ignoring the paper’s language and magnetic compression. The physical constriction requires the magnetic field to surround the object and the magnetic field surrounds the current.
Another piece of faulty logic.

I was not referring to the paper; I was just giving an example about a simple straight wire in a wall. And since the magnetic field of a straight wire vanishes at LARGE distances (in other words at infinity) there is no possible way to determine where the current is and how strong it is, wherever you are. You can measure the strength of the field, and probably how it curves. But this could lead to a strong current far away or to a weak current nearby – how could you judge?
And just with the right-hand rule you can examine the field of a straight wire. However, if the magnetic field curves very strangely (in the form of an hourglass, e.g.) then I wonder how the current looks like, if you just apply the right-hand rule. Tell me, Anaconda! How does the current look like?

DrFlimmer wrote: “It reaches out to the orbit of Saturn which is about twice the distance from the sun than Jupiter. This is quite a distance! ”
But it doesn’t exhibit a constricting and rotating ability. It stretches out the same way the Earth magnetosphere does, but it does’t constrict.

Yeah, and? My statement wanted to say that you can measure a magnetic field at the orbit of Saturn. How do you know it is from Jupiter, if you just measure it? And if it constricts or not, what does it matter? I was just saying that measuring a magnetic field and probably its form, it doesn’t tell you anything if the underlying current (if it exists) is nearby or not. You cannot judge from the strength and the form of the magnetic field where a probably existing current should be – this is impossible!

DrFlimmer wrote: “This means that the envelope is collapsing and hence the star is accreting.”
Magnetic fields compress matter from the outside, not collapse it from the inside via a pull mechanism — that is what is remarkable about the paper.

LOL! You have taken my statement out of context! I think I know why: Do you know what an “inverse P-Cygni profile” is?
And how do you know that the magnetic field compresses the envelope? Have you read the paper, does it clearly state this? I haven’t read such a passage.

The instant paper stated: “We proceeded, similarly to (11), to derive the magnetic field properties by first fitting its morphology…”
So, the shape, “morphology”, of an “hourglass” is important to their analysis.

No, it’s just good to know, how the magnetic field looks like. That it actually takes the shape of an hourglass has been found in their analysis and by comparing this result with another paper they found similarities. And how do you judge from not reading the paper that the hourglass is important to their analysis? I say, they found that it has an hourglass-shape and that is an interesting fact. (This is probably nitpicking, but judging what is important or not from “not” reading the paper, is quite a task!)

DrFlimmer wrote: “I have spoken about this point in a previous post. I think this indicates that the collapsing cloud took the magnetic field with it.”
No.
The magnetic field is constricting on the plasma/neutral matter (as the magnetic field constricts the current density increases and temperature rises and a greater degree of ionization is likely achieved).
Read the paper, the magnetic field is acting on the matter not the other way round.

My interpretation from reading the whole paper is that first the cloud collapses and the pressure of the magnetic field that is confined in the collapsing cloud is acting against the infall. But this is my interpretation. If you read the whole paper, you’ll probably come to another conclusion.

Magnetic fields constrict because of increased current density, this is the Z-pinch effect, a self-reinforcing mechanism (self-reinforcing mechanisms or positive feedback is often seen in electrical dynamics.

The problem is that no one knows if there is a current. It could be that there is none and then there is also no Z-pinch. And as I said before: AFAIU pinches: They normally don’t create an hourglass-shaped magnetic field – but rather an hourglass-shaped cloud (or can, or whatever) after the magnetic field acted!

DrFlimmer wrote: “This is the point which makes it impossible to calculate any underlying current, since Maxwell’s equations are strictly three dimensional. If one is missing (as is the case here) there is no chance to calculate anything.”
Okay, but an inability to measure does not mean an electric current doesn’t exist, it just means current techniques aren’t able to measure it.

That’s true, but astronomy is in most cases bound to two dimensions, although there are techniques to analyze the 3rd one. But especially in the case of magnetic fields those techniques do not work. I wonder if we will ever find a technique to measure (far away) magnetic fields in all three dimensions. So, we will never be able to analyze an underlying current, because it does not reveal itself in another way. That’s too bad!

The instant paper stated: “Given the hourglass magnetic field morphology in the HMC, this spin-down in the HMC suggests magnetic braking, a process proposed to remove the excess of angular momentum. Theoretical models of magnetic braking predict a spin-down qualitatively in agreement with what is shown in Fig. 4 (7, 10).”
Actually, electromagnetic effects are known to dissipate angular momentum. So if the paper’s authors would have considered electromagnetic processes they would not have had to invoked a speculative idea, such as “magnetic braking”. This is another concept the gravity “only” model has had to invoke because it does not consider electromagnetism.

Another LOL! I think “magnetic braking” is just another term for saying “magnetic fields dissipate angular momentum”. Or this is how I understand and translate the term – I don’t think that there are magnetic field lines actually breaking up – they are breaking the rotational speed of the cloud and the core, which is important! What does “magnetic braking” mean in your point of view?
And a third LOL is also necessary! Gee, I told you to forget the term “gravity only”. It’s nonsense! The paper obviously includes magnetic fields. What do you think it is? I think this is an electromagnetic effect, since a magnetic field is in some strange ways related to electromagnetism. “Gravity only” does not exist in science!

Since it’s not apparent whether synchrotron radiation was detected or not. It seems a reasonable follow up to this paper would be to bring to bear instrumentation on this object that can detect synchrotron radiation at a high level of sensitivity and observe & measure whether there is such synchrotron radiation.
If there is synchrotron radiation it adds weight to the electric current/magnetic field, Z-pinch hypothesis, if there isn’t then it goes a long way to falsifying the hypothesis.

Since synchrotron (or the less energetic cyclotron) radiation is produced in the moment when you have a charge and a magnetic field, there is no way to say “oh, synchrotron radiation – it MUST be a z-pinch”. We have a magnetic field and we certainly have charged particles – so there definitely IS synchrotron radiation. The only way to judge if this radiation is due to a z-pinch would be if there is a detailed prediction made by EU, which clearly states to which amount of synchrotron radiation should belong a so-and-so strong z-pinch. Just from the fact that there IS synchrotron radiation one cannot say it is a z-pinch. We need a clear prediction!

I took this last quote “out of context” in order to give it some thoughts:

DrFlimmer keep an open-mind, not this attitude Nereid and the others display — you’ll be much better off.

Well, Anaconda, speaking of “open minds”. Taking your criticism about our rejection of EU, I wonder how you can think that you have an open mind? We say that EU/PC/PU is nonsense – and you state the same about “mainstream” science. Isn’t it the same, just the other way around? Aren’t you then as close-minded as we are?
And do you really think that you can judge what is really right and what is not so right? Don’t you think that the ability of reading and understanding a paper with all its figures, tables, equations and technical terminology is a better way to think about what is going on than just be able to read a few press releases?
You can still send me an email and I would gladly send you a copy of the paper. Then you can read the whole thing for yourself and draw your own conclusion that are not based on my (indeed arbitrary) quotes.
DrFlimmer

Dammit. Something went wrong with the last but one blockquote. The second of the three paragraphs before the last blockquote should also be a blockquote… dear reader, please take this in mind

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