Here comes the "roundabout" part to get to the thread title:
Where we consider large / dynamic magnetic fields, we must also bear in mind that magnetic fields do not stand alone. They stand shoulder to shoulder with the collective motions of like charged "charge carriers" (electrons, protons, ions).
(Wikipedia on the Electromagnetic Field)
http://wikipedia.org/wiki/Electromagnetic_field
In essence, stationary charge carriers are responsible for the electric field. Collective net motion of like charge carriers (in an electric current) are responsible for magnetic fields. In the case of permanent magnets (I believe), the magnetic field is based upon the collective net lock-step motion of the electrons in the clouds bound around the atomic nuclei.The electromagnetic field is a physical field produced by electrically charged objects. It affects the behavior of charged objects in the vicinity of the field.
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The field can be viewed as the combination of an electric field and a magnetic field. The electric field is produced by stationary charges, and the magnetic field by moving charges (currents); these two are often described as the sources of the field. The way in which charges and currents interact with the electromagnetic field is described by Maxwell's equations and the Lorentz force law.
So, now we've come the roundabout way to understanding that where magnetic fields are thought to play a role, the collective net motion of charge carriers (electric currents) involved is also to be considered of equal importance, since the magnetic fields appear to have their genesis in those electric currents. Now, let's see what they have to say about electric currents (by way of understanding that magnetic fields may be of primary importance and by extension the electric currents must be of equally primary importance).
(Magnetic Fields Crucial To Star Formation, Astronomer Says
Translation [by substitution]: [Electric Currents] Crucial To Star Formation, Astronomer Says)
http://www.sciencedaily.com/releases/19 ... 080925.htm
(Star formation? All a bit of a wind up...)Observations by a University of Illinois astronomer have shown that magnetic fields are a critical component controlling when and how stars form.
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"Theorists have performed extensive simulations that show how an interstellar cloud might collapse in the presence of a magnetic field," Crutcher said. "In those studies, the researchers could prevent the clouds from quickly collapsing and forming stars, and they could get rid of the extra angular momentum, by making the magnetic fields sufficiently strong."
To test theory against data, Crutcher measured the strengths of magnetic fields in 27 interstellar clouds of varying molecular density. By comparing each cloud's magnetic energy with its gravitational energy, he found that magnetic fields were strong enough to control the rate of collapse and to assist in the star-formation process by providing a means of shedding excess angular momentum.
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"By flinging a small amount of matter outward along the magnetic field lines, the magnetic waves can remove a huge amount of angular momentum, making star formation possible," said Crutcher, who reported his findings in the August issue of the Astrophysical Journal.
http://www.theregister.co.uk/2007/11/01/star_formation/
Hmm, a helical magnetic field... Where have I heard that before? Filamentation in Birkeland currents? Could the helical magnetic field have a genesis in helical electric currents?UK astronomers have discovered that the material flowing out of newborn stars contains a coiled, spring-shaped magnetic field.
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The theory is that as the gas collapses to form the spinning protostar, the interstellar gas twists the magnetic field that permeates the universe, winding it up like a corkscrew. Gas that is spinning too fast spins out along the field lines creating the polar jets observed on so many new stars.
But until now there was no real evidence to support this explanation for the process, the Hertfordshire team says. Using the Anglo-Australian Telescope (AAT) in New South Wales, Australia, Dr Chrysostomou and his team measured the circular polarisation of near-infrared radiation from a young star's jet. They were then able to reconstruct the structure of the magnetic field in the outflow.
Dr Phil Lucas, lecturer at the University of Hertfordshire, commented: "When we combine our observations with sophisticated computer modelling techniques, we were able to show that the shape of magnetic field that could reproduce our observations could only be helical."

(Newly Seen Force May Help Gravity In Star Formation)
http://www.spacedaily.com/news/stellar- ... y-05g.html
I'll make this brief:
If I may make a suggestion to the XMM-Newton team: What is more related to "magnetic fields" than "electric currents?" Electric currents are also a simple method of generating x-rays, killing two birds with one stone!The observation, made primarily with the European Space Agency's XMM-Newton observatory, suggests that some unrealized, energetic process - likely related to magnetic fields - is superheating the surface of the cloud core, nudging the cloud ever closer to becoming a star.
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"Previous observations have captured the shape of such gas clouds but have never been able to peer inside. The detection of X-rays this early indicates that gravity alone is not the only force shaping young stars."
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The detection of magnetic fields from an extremely young Class 0 protostar provides a crucial link in understanding the star formation process, because magnetic field loops are believed to play a critical role in moderating the cloud collapse.
(Diamagnetic effects during the early stages of star formation)
http://journals.cambridge.org/action/di ... &aid=18077
(Magnetic fields and star formation – new observational results)The role of magnetic fields during the initial stages of protostellar cloud collapse is investigated, in particular with respect to the scenario where the magnetic force can be an effective compressor due to diamagnetic effects. A multifluid approach involving electrons, ions of different atomic masses and neutrals is adopted, where each species is treated separately. The electron fluid is compressed by the magnetic pressure force, and the other ion species are pulled by the collective electric field developed by the space charge separation. The neutrals are also dragged owing to collisions with the ions. The difference in charge-to-mass ratio ensures that each ion species is accelerated differently, resulting in a distribution following their atomic masses. This model explores the scenario where the electromagnetic forces can achieve a supercritical mass-to-flux ratio in a magnetized cloud before dynamical collapse due to gravity takes over.
http://journals.cambridge.org/action/di ... aid=973140
If magnetic fields play a critical role in stellar evolution, then electric current must plan an equally large role, per Maxwell (being that "magnetic fields" are intimately linked to "electric currents"). Likewise, it looks like observational support is growing for the notion that stars form by matter accumulating along field lines. But what follows field lines? Charged particles do. I don't believe "neutrals" generally do, however. Field-aligned currents (like charged particles involved in net flows along field lines) are also known as Birkeland currents.Although the subject of this meeting is triggered star formation in a turbulent interstellar medium, it remains unsettled what role magnetic fields play in the star formation process. This paper briefly reviews star formation model predictions for the ratio of mass to magnetic flux, describes how Zeeman observations can test these predictions, describes new results – an extensive OH Zeeman survey of dark cloud cores with the Arecibo telescope, and discusses the implications. Conclusions are that the new data support and extend the conclusions based on the older observational results – that observational data on magnetic fields in molecular clouds are consistent with the strong magnetic field model of star formation. In addition, the observational data on magnetic field strengths in the interstellar medium strongly suggest that molecular clouds must form primarily by accumulation of matter along field lines. Finally, a future observational project is described that could definitively test the ambipolar diffusion model for the formation of cores and hence of stars.
It seems to me that (if I've not too egregiously made any false leaps of logic) Birkeland currents have now been implicated in stellar formation? Again, if my logic isn't too far off base in comparing matter following field lines to Birkeland currents (field-aligned currents) with the assumption that "neutral" matter won't tend to follow field lines as electrically charged matter will...
Cheers,
~Michael Gmirkin
