Saturday, July 16, 2011

Electric Universe: Measurement of the Electric Current in a Kpc-Scale Jet

A couple of weeks ago, I came across a paper on the Cornell preprint server that I suspected the Electric Universe (EU) crowd would pick up before long...

“Measurement of the Electric Current in a Kpc-Scale Jet”
Kronberg, Philipp P.; Lovelace, Richard V. E.; Lapenta, Giovanni; Colgate, Stirling A.

I'm sure the EUers will be all over this, claiming that it means mainstream science is finally coming around to their ideas.  But if they actually read the original paper, and not just the press-releases, they would discover that they were wrong (again)...

The introduction of the paper reveals that this work is actually based on a model for galactic jets that dates back to 1976 with work by Roger Blandford (Accretion disc electrodynamics - A model for double radio sources) and independently by Lovelace (Dynamo model of double radio sources), one of the co-authors of the current paper. 

The model relies on the jets of plasma being collimated by a magnetic field and particle flows driven by an electric field created by an accreting black hole.    The model has been studied heavily since first proposed by Lovelace and Blandford.  The electromagnetic properties of the jet are determined through the rotation measure (RM) of the Faraday Effect (wikipedia).  Through this method, they obtained an electron density of 1.4e-5 electrons/cc and a current of 3.8e17 amps directed away from the galactic nucleus.

I suspect EUers will want to compare this result with the Alfven galaxy model, but there may be a problem with that.  The earliest reference I can find where Alfven suggested something similar is in a few paragraphs in a paper from 1977:

Electric currents in cosmic plasmas by Hannes Alfven.
Alfven describes a galaxy central radio source as a unipolar inductor, but the description is very qualitative.  There is not even a single numerical estimate of currents expected or the visible flux. 

Alfven went into a little more detail in 1978 with
Double Radio Sources and the New Approach to Cosmical Plasma Physics by Hannes Alfven

providing at least a graphic, but still no way to estimate the luminosity and other characteristics one could expect to measure from Alfven's proposed galaxy configuration.  An examination of the citation lists for both of Alfven's papers reveals no citations for either Blandford or Lovelace.  Two years after the fact, Alfven was not acknowledging others who not only preceded his effort, but developed the model in far more detail.

When you look at the contributions made by others prior to Alfven,  one begins to realize that Alfven's work described little that wasn't already known.  The only aspect of the model that could be considered as a contribution by Alfven could be recognizing the need for a return circuit in the 1977 paper.  However, I regard the rigor of the 'return circuit' questionable.  MHD simulation volumes are generally modeled as closed systems so the same flows have to return full circle, but the intergalactic medium (IGM) is not a closed system.  Charge imbalances can be remedied by charges flowing back towards the galactic center from the IGM, but nothing requires them to be the same particles emitted in original the jets of the galaxy, just that the quantities are sufficient to balance the charge.

Probably the greatest deficiency of Alfven's papers is that while Alfven describes the central engine as a unipolar inductor, there is NO information on how such a structure could be built in Nature.  Alfven's central source is a black box with no way to even estimate its power capabilities.  For all intents and purposes, Alfven's unipolar inductor could've been a machine built by alien civilizations in all these radio galaxies.

Meanwhile, mainstream astronomy had an object that fit the bill for creating a unipolar inductor (AKA a homopolar generator, Wikipedia): an accreting black hole.  The theory had sufficient mathematical development that one could develop testable predictions with it.  Accreting plasma around a black hole forms a highly conducting layer just outside the event horizon, making a near perfect conductor that couples to magnetic field generated by the differentially rotating accretion disk.  This idea is also related to work by Blandford and Znajek (Electromagnetic extraction of energy from Kerr black holes).   Black holes have also been treated as resistors and rotors in circuit elements in a number of configurations (see Black Holes: The Membrane Paradigm, 1986, and related papers by Kip Thorne).

It is ironic that objects EU supporters most deny exist (black holes & neutron stars) are the best known producers of large electric fields in the cosmos.

Problems for Electric Universe
  • Alfven was NOT the first to propose this configuration for radio galaxies.  He made, at best, only very minor contributions to the model, and nothing that contributed to testing the model against actual observations.
  • The Blandford & Lovelace model, like Alfven's model, is inconsistent with Peratt model because the current seen is strictly a product of the galaxy's central engine, and not due an external source.  See (Scott Rebuttal. II. The Peratt Galaxy Model vs. the Cosmic Microwave Background, Still no electric currents powering the galaxies...).
  • Perhaps the greatest problem it makes for EU is that it demonstrates that we can measure extragalactic currents.  This means the EU whines about undetectable 'dark currents' are moot.
  • In Blandford (1976), the author even notes that his proposed configuration “therefore acts as a unipolar inductor, generating an electric field, E, in the inertial frame.”  It demonstrates that astronomers have long considered the effects of electric fields and currents in the cosmos, in spite of EU denials.

While I was researching & assembling this post, Nereid pointed me to this on the Thunderbolts site:
Universe's Highest Electric Current Found
Funny, it appears some thunderbolt forum members actually read the paper, but I have yet to see any acknowledgement of how long ago this model was actually proposed.

23 comments:

Siggy_G said...

Indeed, there have been numerous papers on "the cosmic battery" and other proposed accretion generated electric currents. The thing to note is of course that large scale currents are detected in the first place.

Then riddle me this: aren't one of the main argument against the Electric Universe, that electric currents can't exist over stellar or galactic distances due to 'Debye shielding'? How come this is not an issue in the discussed paper (and related ones)?

W.T."Tom" Bridgman said...

To Siggy_G:

Odd, I only find you advocating Debye screening as a mechanism to block radiation emission.

As I noted in these posts, I suspect Debye screening can't operate in cases where electrons and ions have significantly different velocities. Debye screening is defined in a thermal plasma. If any significant screening operates in non-thermal plasmas, it is not called Debye screening and I have yet to find evidence of this issue in the literature.

See posts below and the comments:

Electric Universe: Everything I needed to know about science I learned from watching Star Trek?

Charge Separation in Space

Electric Universe: Real Plasma Physicists Use Mathematical Models!

Siggy_G said...

That's interesting – and agreeing that Debye screening don't seem to apply in scenarios where electron and ions velocities are significantly different.

Also, the particles on the far side of a system don't neccesarily need to be driven by the direct electric field of a central net charge. The particles' travel aren't linear or one dimentional all the way through, like considered within the Debye screening formula. I believe that in a dynamic and sparse scenario like within astrophysical plasma, numerous and turbulent "local" electric fields can occur increasingly along the path towards the central net charge. (This would be due to temporary and regional inbalances in electrons or positive ions in a filamentary structure). In average, this constitutes a global and radial electric field for the system, but it is not neccesarily this one vector the particles follow at any given time throughout the system. That's another reason why I don't think Debye screening applies in interstellar and intergalactic scenarios as they may in higher density plasmas, where the mean free path is way shorter.

Anonymous said...

Siggy_G,

It's nice to have interesting thoughts.

And if you're really into this sort of thing, I do not doubt you could write the most fascinating of science fiction short stories.

But if you are seriously interested in science (astrophysics in this case), don't you think you need to roll up your sleeves and start doing some real work?

Alternatively, if you genuinely believe you have discovered an alternative path to making sense of the universe, one that involves a radical re-writing of the foundations of the relevant parts of science (physics, in this case), why are you fussing around with trivia like this?

Nereid

Siggy_G said...

(Discard this comment if it already went through earlier on)

Nereid,

I'll see what I can manage - I haven't attempted to write or submit any actual papers yet, but it would sure be interesting to have a go; including some simulation approaches.

If you by 'trivia like this' mean 'forum and comment field activity', then my intentions and interests are probably not much different than yours or Tom's.

If you mean 'bringing up insignificant issues', I'd say Debye screening is one of several important topics, because it is one of the reasons many people dismiss electric currents existing over steller or galactic distances. Yet, they are detected, but with a gravity-only field interpretation. There's nothing radical about the physics in my description above. It is quite basic; there will be electric cirquitries between regions of one net charge and regions of the opposite net charge. The question is if there is data that can be interpreted towards verifying the described scenario - or not. If so, it would also indicate that the interplanetary medium can allow circuitries between the heliopause and the Sun, dispite a radial and outward emission of particles within the medium (those particles travel outwards due to thermal escape velocities from the corona, and would only regionally be affected by electric fields, like described above. The electric field is according to Scott/Thornhill thought to be relatively weak along most of that distance, with references to plasma discharge and voltage graphs).

Anonymous said...

Siggy_G,

If all you do is apply textbook plasma physics to astronomical observations, what would make your results different from any of the thousands (yes, thousands!) who have already done exactly this?

Alternatively, if you genuinely believe that Talbott, Thornhill, et al. are onto something - with their 'qualitative science' and their permanent promise that paradigm-shifting *quantitative* papers are just "a few months' away" - you would surely be wasting your time to bring your grasp of textbook plasma physics up to PhD level, wouldn't you?

Nereid

Siggy_G said...

Nereid,

Can't the "thousands of contributors" point be said about any field in science? The difference lies in interpretation of observations and application of theory - and perhaps a revision of consensus notions.

There surely aren't thousands of contributors like H. Alfven, A.Peratt, C.G. Felthammer, A. Brynjolfson and D.Scott. Over stellar and galactic distances, gravity is the only applied field (and point of view) by the remaining thousands of contributors, it appears. I'm not so sure that gives fruitful output in the long run. I also wonder if such a constraint is in line with textbook methodology... (when other factors can't be ruled out)

W.T."Tom" Bridgman said...

To Siggy_G,

Have you already forgotten the original post above?

Not only did Alfven not develop the radio source model to a testable level as much as others, but I've yet to find evidence that he published the idea prior to others! Alfven has received recognition in many areas of astrophysics, but here's a case where he was a weak 'me too'.

Alfven & Falthammar (and probably Peratt as well) know that the Sun is not electrically powered, so why invoke them as EU supporters? Page 14-15 of Alfven & Falthammar's "Cosmical Electrodynamics" (1963) presents a very simple analysis of why the Sun can't support a significant net charge.

Don Scott's "On the Sun's Electric Field" uses an electrostatic field, despite Thornhill's claims of it's invalidity(ref1, ref2). What's up with that? More on Scott's 'model' in a future post.

Anonymous said...

Siggy_G,

"If all you do is apply textbook plasma physics to astronomical observations, what would make your results different from any of the thousands (yes, thousands!) who have already done exactly this?" - that's me.

"Can't the "thousands of contributors" point be said about any field in science? The difference lies in interpretation of observations and application of theory - and perhaps a revision of consensus notions." - that's you.

If that's what you want, or intend, to do, then go for it. When you think you've got some sound results, write them up and publish them; in the meantime, why are you wasting your time posting comments to this blog?

"There surely aren't thousands of contributors like H. Alfven, A.Peratt, C.G. Felthammer, A. Brynjolfson and D.Scott. " - you again.

The first three no longer write (publish papers) in this area, as far as I know. While there have been some who've done limited work on the approaches they used, none of it has gone anywhere. Certainly, none of the hundreds (thousands?) of members of the TB forum seem to have actually published anything along these lines (what a waste; imagine if only a small fraction of the person-years' of effort that's gone into writing material for that forum had been devoted to taking Alfvén's work further!)

The last two have published - using the word in a very broad sense - nothing of value, with respect to the application of plasma physics, have they? In this respect, there certainly are thousands like them.

For the rest, the only thing I'd add to what Tom already wrote is this: you seem rather unfamiliar with what's in standard astrophysics textbooks (perhaps it's time for you to start looking for a university programme that offers an appropriate PhD track?).

Nereid

Siggy_G said...

Tom,
My response (in reply to Nereid's) was about mentioned contributors that have researched the effect of large scale electric currents and EM fields is cosmic plasmas (which in any case is a basis for the Electric Universe). I don't see you refuting that the majority only considers gravity fields in cosmic scenarios.

You're right, Alfven (and Perrat) didn't consider an Electric Sun, only its surrounding electrodynamic effects. The extension of Alfven's (and Perrat's) notions are mainly put forward by Thornhill and Scott. Looking forward to your future post. Ps: Scott mentions in his third assumption in your linked paper that electrostatics isn't sufficient.

Here's a paper from 2010 that considers a net charge of stars: http://www.prespacetime.com/index.php/pst/article/view/93/89 Personally, I suspect that the actual scenario of stellar cirquitry is even more complex than this (such as the surface having spikes of charge and not an even one).

Siggy_G said...

Nereid,
I refered to what research is about in general - different approaches for applying theory (hereby textbook plasma physics) to data/observations. In some cases that may include or result in a revision of consensus notions. Two researchers can have completelly different approaches, look for different mechanics and hence stipulate different scenarios. Especially if one uses a 'mass and gas' approach and the other a plasma process approach. Alfven and Peratt's papers are examples of different approaches from the norm in astrophyscs. So, that is why 'my results' could be different from 'the thousands of others'.

W.T."Tom" Bridgman said...

To Siggy_G,

Actually, an electrostatic approach gets you further than you might think. In a configuration where free electrons & ions aren't moving together (as in a quasi-neutral plasma such as the solar wind), you will ALWAYS get regions of net charge.

i=ion, e=electron, velocity & density

current density = idensity*ivelocity - edensity*evelocity

charge density = idensity-edensity

evelocity & ivelocity will be different in any configuration driven by an electric field and will vary along the field. If the total current is constant, the charge density will change along the path, in the case of the Scott model as a radial charge distribution. Langmuir & Blodgett first explored this problem in the 1920s and got much further than Scott.

Anonymous said...

"Alfven and Peratt's papers are examples of different approaches from the norm in astrophyscs." - Siggy_G.

Neither of these guys' results, using this different approach, went anywhere, did they?

"So, that is why 'my results' could be different from 'the thousands of others'."

I "could" become the next Secretary General of the UN ... but I certainly won't if all I do is sit around and write comments on various blogs and in discussion fora.

When may we expect to read your first results, in a paper that meets the minimum standards for acceptance in an astrophysics journal?

Nereid

gene said...

My my! What started out was a discussion into electric currents in space has degenerated into a pissing contest. On to another site where real issues can be explored. This site is too hostile and full of "I went to such and such university", etc. It reminds me of the time I spent working in the federal government as an engineer...too much nonsense and too many pissing contests....

Anonymous said...

W.T."Tom" Bridgman said...
About Alfven model
"There is not even a single numerical estimate of currents expected or the visible flux."
If you read the papers by Blandford or Lovelace 1976 you will notice the total absence of these numerical value.
While Alfven in 1978 provide a quantitative analysis of his model in chapter 9 on page 10 of
Double Radio Sources and the New Approach to Cosmical Plasma Physics by Hannes Alfven
http://adsabs.harvard.edu/abs/1978Ap%26SS..54..279A

W.T."Tom" Bridgman said...

To Anonymous,
Okay, let's take a closer look at Alfven's paper.

The 1978 Alfven paper, while presenting more details of Alfven's model, gave nothing by which we can compare to actual measurements! His only calculation is computing an induced voltage based on the rotational velocity and magnetic field for our own galaxy and gets a voltage of 3e16 volts. But do we have any way for astronomers to MEASURE that? We can't go out to the galaxy and attach some leads across the jets, plug them into a voltmeter and get a measurement, so from a practical perspective, the result is useless. We can't even estimate this value for other galaxies.

Meanwhile, the Lovelace paper, while computing the voltage and current, also computes the beam luminosity (equation 5) which we can measure. Other computed quantities, such as beam density (equation 7) and speed (equation 8) can be used by others to estimate other quantities such as the profile of the emission spectrum, if it is composed of synchrotron radiation, bremsstrahlung, compton scattering, etc.

In addition, look at the glaring gaps in Alfven's paper. Even for his voltage computation, he uses values estimated nearby for our own galaxy, because, in his own words, "We know very little about these quantities for the central galaxies associated with double radio sources."

Alfven does not examine the source of the 'unipolar inductor' at the galactic center. Again, what drives it? Aliens? Magic? At least the black hole in the Lovelace model is generating TESTABLE predictions.

Alfven notes that "the general theory of formation of such [double] layers in space is not yet worked out in detail." Yeah, that is another serious shortcoming. Actually, we do know that double layers require energy from other sources to form.

And note Alfven's description of 'exploding' double layers: "The energy release in the double layer may be so large that at the point where it is set up the glass tube glows and even implodes." IMPLODES. What is happening here? How much of this 'explosion' is due to the glass heating to the point that it weakens so the exterior laboratory atmospheric pressure can collapse the lower-pressure discharge tube? This is not a sudden energy release of the double layer itself, it's work by the atmosphere collapsing a vacuum!

Ever broken an old-style television picture tube? The amount of energy needed to break the glass is small compared to the KABOOM! of the collapsing tube, which I know from experience can be heard for several blocks. ;^)

Anonymous said...

W.T."Tom" Bridgman said...

To Anonymous,
Okay, let's take a closer look at Alfven's paper.

The 1978 Alfven paper, while presenting more details of Alfven's model, gave nothing by which we can compare to actual measurements! His only calculation is computing an induced voltage based on the rotational velocity and magnetic field for our own galaxy and gets a voltage of 3e16 volts. But do we have any way for astronomers to MEASURE that?
------------
The same way that the measurement was made for determining the current value here
http://adsabs.harvard.edu/abs/2011arXiv1106.1397K
Notice Alfven quantitative prediction here which match the observed value
http://articles.adsabs.harvard.edu/full/gif/1978Ap%26SS..54..279A/0000289.000.html

W.T."Tom" Bridgman said...
Meanwhile, the Lovelace paper, while computing the voltage and current, also computes the beam luminosity (equation 5) which we can measure. Other computed quantities, such as beam density (equation 7) and speed (equation 8) can be used by others to estimate other quantities such as the profile of the emission spectrum, if it is composed of synchrotron radiation, bremsstrahlung, compton scattering, etc.
------
Alfven also treat these quantities and provide a mechanism explaining the production of high energetic particles:
http://articles.adsabs.harvard.edu//full/1978Ap%26SS..54..279A/0000290.000.html

Notice that in the 2011 paper Lovelace and all are still unable to provide a mechanism explaining the production of high energetic particles
see page 4 chapter 6 Discussion and implication
http://adsabs.harvard.edu/abs/2011arXiv1106.1397K

"The system evidently needs to incorporate a “transducer”
that converts the Poynting energy flux into high energy particles
which then produce synchrotron radiation. These issues and the
complex lobe structure will be discussed in a subsequent paper."

W.T."Tom" Bridgman said...
Alfven does not examine the source of the 'unipolar inductor' at the galactic center. Again, what drives it? Aliens? Magic?
Alfven notes that "the general theory of formation of such [double] layers in space is not yet worked out in detail." Yeah, that is another serious shortcoming. Actually, we do know that double layers require energy from other sources to form.
----
Alfven provide the source of the unipolar inductor and how the double layer is formed here:
http://articles.adsabs.harvard.edu//full/1978Ap%26SS..54..279A/0000285.000.html
W.T."Tom" Bridgman said...
At least the black hole in the Lovelace model is generating TESTABLE predictions
---------
Maybe after reading this peer reviewed paper you will revise your position about the assumed super massive black hole
http://www.nrcresearchpress.com/doi/abs/10.1139/p89-158

Black holes: the legacy of Hilbert's error

Leonard S. Abrams

Canadian Journal of Physics, 1989, 67(9): 919-926, 10.1139/p89-158

W.T."Tom" Bridgman said...

To Anonymous:

Now you're cheating, since you have moved the goal posts, now trying to compare Alfven's '78 paper to Lovelace's 2011 paper while ignoring that much of the foundation for Lovelace 2011 is from Lovelace '76. Lovelace '76 demonstrated tying the current value to observable quantities. Alfven's value is for a different galaxy (specifically the Milky Way galaxy), the mechanism is radically different, relying on magnetic induction from galactic rotation of material in the general galactic magnetic field, and, as Alfven notes "which easily may be wrong by one or more orders", largely because he has the choice of any radial position and he wants providing a wide range of possible velocities and/or magnetic fields.

Yet how many of the quantities needed to test Alfven's model were available for the galaxy 3C303? Alfven doesn't provide a connection to the radio luminosity of the jet where we do have measurements (Lovelace does), but do we have a particle flux and energy spectrum from 3C303? Probably not, so there's another quantity we can't connect. Alfven basically says we've seen particles with this high energy (presently no reliable test if they are from 3C303 or some other galaxy, or even some other type of object), from some random directions on the sky.

And details of this 'transducer' mechanism are described in the later paper (Transmission line analogy for relativistic Poynting-flux jets). Your point?

The configuration Alfven describes for the inductor and double layer in the referenced papers apply to the Earth's magnetosphere. Alfven provides limited details on how this could be applied to galaxy environments.

The bottom line is that Lovelace and others laid the foundations for this model BEFORE Alfven, and in far better detail. Others were able to develop the model in even more detail (as of this writing, 430 references to Lovelace '76) while Alfven's model deficiencies of lack of connection to things we could actually MEASURE for galaxies continued for many years. Note only 23 references to Alfven '78 and only a fraction of them are trying to apply the results to galaxies.

That Alfven obtained a similar result for total current for our galaxy to the 3C303 case by assembling a set of parameters in a dimensionally consistent way is not too surprising. For systems operating at a reasonable steady state, this type of 'dimensional analysis' gives good agreement regardless of the details of the mechanism, but it is the DETAILS of the mechanism that determines the correctness. I've discussed this before, see The "Van Allen Hypothesis": Abandoned Science Finds New Life in Pseudoscience?.

W.T."Tom" Bridgman said...

To Anonymous (continued)

Too many people harp on the *theoretical* models of black holes which suggest it is possible to cross the event-horizon if the black hole forms in a total vacuum. I have doubted this for many years. Before everyone romanticized the 'black hole' term, these objects were occasionally described as 'collapsed stars' in older literature. Astrophysical black holes form as a result of a collapsing mass and to a remote observer, the surface of the star will never cross the event-horizon. Nor will we observe infalling matter pass through the event horizon (though there were some press releases some years ago that used this analogy). Emission from infalling heated matter is eventually redshifted into undetectablility. While properties of the interior Schwarzschild solution may be interesting, I suspect for any practical applications, only the exterior solution beyond 2GM/c^2 is relevant, and that gets tested at every opportunity, and is so far holding up very well, regardless of crank claims to the contrary.

You make the mistake of looking for tidbits here and there which you can treat like debate-scoring points, failing to recognize that the science is a process and all the parts must connect together to form a consistent whole. Scientific consensus is not determined just by scientists 'agreeing', but agreeing with the demonstration that we can reliably identify the relationships between the quantities that we can measure.

Cosmos1999 said...

About black holes:
Here a peer reviewed paper confirming Leonard S. Abrams claims that you qualify as being crank...
Reconsidering Schwarzschild's original solution

S. Antoci1,
D.-E. Liebscher2
Author Information

1

Salvatore Antoci, Dipartimento di Fisica “A. Volta” and INFM, Pavia, Italy
2

Dierck Ekkehard Liebscher, Astrophysikalisches Institut Potsdam, Potsdam, Germa
Article first published online: 20 JUL 2001

DOI: 10.1002/1521-3994(200107)322:3<137::AID-ASNA137>3.0.CO;2-1

http://arxiv.org/abs/gr-qc/0102084
Published here:
http://onlinelibrary.wiley.com/doi/10.1002/1521-3994%28200107%29322:3%3C137::AID-ASNA137%3E3.0.CO;2-1/abstract;jsessionid=B4E08C20EE1D3E5C2D3F8F6ECB7C1933.f04t03

First they begin the paper by a pre-
liminary reassessment of the historical record as conditio sine qua non for
avoiding any misunderstanding
Chapter 1
1. Introduction: Schwarzschild’s solution and the
“Schwarzschild” solution
Nowadays simply talking about Schwarzschild’s solution requires a pre-
liminary reassessment of the historical record as conditio sine qua non for
avoiding any misunderstanding. In fact, the present-day reader must be
firstly made aware of this seemingly peculiar circumstance: Schwarzschild’s
spherically symmetric, static solution [1] to the field equations of the ver-
sion of the theory proposed by Einstein [2] at the beginning of November
1915 is different from the “Schwarzschild” solution that is quoted in all the
textbooks and in all the research papers. The latter, that will be here al-
ways mentioned with quotation marks, was found by Droste, Hilbert and
Weyl,

Cosmos1999 said...

Tom Bridgman said:
Yet how many of the quantities needed to test Alfven's model were available for the galaxy 3C303? Alfven doesn't provide a connection to the radio luminosity of the jet where we do have measurements (Lovelace does),
------
Nowhere in the 1976 paper Lovelace talk about galaxy 3C303
specifically. That is a preliminary model.Like Alfven was a general model developed further by Perratt after Alfven death.

W.T."Tom" Bridgman said...
That Alfven obtained a similar result for total current for our galaxy to the 3C303 case by assembling a set of parameters in a dimensionally consistent way is not too surprising. For systems operating at a reasonable steady state, this type of 'dimensional analysis' gives good agreement regardless of the details of the mechanism, but it is the DETAILS of the mechanism that determines the correctness.

And details of this 'transducer' mechanism are described in the later paper (Transmission line analogy for relativistic Poynting-flux jets). Your point?
------
My point is presented below this concerns "the DETAILS of the mechanism that determines the correctness."
I notice that they also applied it for M87

Here a paper from Perratt which have perfectioned Alfven model further...
See page 7 of Perratt paper about Cygnus A which is attributed by the mainstream as being the proof of super massive black holes.
While in fact it is only a double radio source galaxy.
See page 17 for M87.
All matching observation as demonstrated.
My point is that if you apply Occam's razor principle:
"a scientific and philosophic rule that entities should not be multiplied unnecessarily which is interpreted as requiring that the simplest of competing theories be preferred to the more complex or that explanations of unknown phenomena be sought first in terms of known quantities"
Alfven / Perratt model for explaining galactic jets wins.No super massive black holes needed!

W.T."Tom" Bridgman said...

Response to Cosmos1999

You did not provide a reference to the Peratt paper mentioned and your description matches none in my collection (since Alfven died in 1995). However 1986ITPS...14..639P, and 1986ITPS...14..763P talk about these sources, but they require cosmic-scale Birkeland currents. The Birkeland currents Peratt requires for these sources should be detectable by their microwave emission, a fact noted by Peratt himself. That emission was not found.
Electric Universe: These are not the filaments You're looking For…

3C303 is mentioned in (Measurement of the Electric Current in a kpc-scale Jet) with Kronberg which I have been referring to as 'Lovelace 2011' since they have overlapping context.

Other observations which support the accreting black hole interpretation for active galactic nuclei:

- Line profile of iron K line fits with accretion model.

- Doppler profiles of other spectral lines are consistent with accretion around high-mass object. How does the Hubble Space Telescope search for black holes?

- Tracking of stars around center of milky way gives mass value of millions of solar masses while small size. Black Holes at the Centers of Galaxies, Is there a black hole at the center of the Galaxy?

- Rotating, accreting black holes have behavior analogous to a unipolar inductor.
Electromagnetic Winds from Black Hole/Disk Magnetospheres

All are consistent with exterior solution for Schwarzschild or Kerr-Newman metrics

No equivalent have been presented by supporters of the Alfven model.  Saying, 'the Alfven model can explain that with process x' is meaningless if you cannot provide algorithms for computing the quantities in the model for other measurable observables AND consistent with other aspects of the model.

- UVA: Characteristics of AGN

- Reverberation mapping of AGN

- X-ray 'echoes' map a supermassive black hole's environs

Perhaps plasma cosmology supporters want to invoke Marklund convection?  In that case, they must show the details. For a given radius in the disk, what is the temperature and velocity?

But before they can do that, they need to deal with the problem that Marklund convection requires an axial current moving in one direction through the disk, while the observations show axial currents in TWO directions moving out from the disk.

Good luck with that…

W.T."Tom" Bridgman said...

To Cosmos1999

Where did I say Abrams was a crank?

There are other papers predating Abrams that ask questions about the various solutions to the Einstein field equations (Physical Review: Reality of the Schwarzschild Singularity, Completion and Embedding of the Schwarzschild Solution). Mathematicians like to argue about the various solutions found. Abrams 2001 update contains no references to observational implications because it appears to deal with only the interior part of the solution.

Per review is not guarantee of correctness. Loads of papers make it through peer review that are incorrect and it takes the wider community to demonstrate the error. Why Don't Rebuttals Appear in Scientific Literature?, Podcast Episode 93: The Importance, Methods, and Faults of Peer Review)

Sometimes authors find an alternative treatment of a model.

1) If their alternative can be experimentally or observationally distinguished from the existing model, the alternative wins.
2) If they are not experimentally or observationally distinguishable but could be with improved technology, both models may hang around until the technology improves to make the test, at which point, rule 1 applies. However, until that time, the version which is fundamentally simpler will probably remain dominant.

The author can only be described as a crank if they insist on promoting an error even after corrections are identified (Scientists, Eccentrics, Cranks and Crackpots). See also "Discordant Redshifts - A Post Mortem",

Complaining about the use of the term 'black hole'? All evidence is a small, but high-mass object, at the heart of these systems. In all cases, we can only access the 'exterior solution', so arguing about the nature of the event horizon or interior is kind of like arguing how many angels can fit on the head of a pin. There is currently no way to test them. Mathematicians like to argue about them, but for all practical applications, only the exterior solution is relevant in astrophysics.

However, whining about the terminology seems to be the best the real cranks can do since I have yet to see one demonstrate the technical skills to:

1) identify areas where the different ideas predict different results which we might be able to measure, or
2) design or even build experiments with the precision necessary to distinguish their alternative model to the current accepted model.

Confronted with the dilemma of conflicting models, real scientists adopt one of the strategies above.

Pseudo-scientists just whine and cry and complain.

So...What Happened?

Wow.  It's been over eight years since I last posted here... When I stepped back in August 2015,...