Spiral Galaxies Without Dark Matter

Nereid · #1 (**permalink**) 18-September-2005, 02:03 PM

Nereid's NOTE: This thread was created by me, in response to TomT's request, originally in the Mass Exodus From Big Bang Begins thread, because the topic of whether Peratt's work on simulating spiral galaxies, using a Plasma Universe approach, was becoming a distraction from the general discussion.

It is also consistent with the tidying up I did, as BAUT transitioned to the new (ATM) rules; specifically, to consolidate discussion of PU/PC/EU/ES/etc ideas into a small number of threads of their own.

Quote:

Originally Posted by VanderL

Quote:

Originally Posted by Cougar

Oh, that's the theory you "like better"? Is this theory claiming that a long-range electromagnetic field is the thing that is keeping the galaxy from flying apart? I suppose such a thought should deserve consideration. So let's consider.... Apparently the spinning galaxy itself is thought to generate this field? But gee, it seems to be spinning awfully slowly. Humans have come to have a pretty good handle on practical electromagnetism. Is there any way you can show that this galactic action could "generate" such a strong EM field to be able to alter the orbits of very massive bodies? And not just alter. The effect must be huge. It's got to be 8 or 9 times the effect of gravity from all the stars and dust (and central black hole) that we know inhabit our galaxy. As Rocky Kolb says, "We find that the galaxy has a much larger mass than the sum of all the stars, dust, and other things we "see." The shortfall is not just a few percentage points, but most of the mass of our galaxy seems to have been left unaccounted."

So feel free to explain how big this field strength has to be and how such a massive EM field is generated throughout the galaxy and extending well outside its edges

Peratt's work showed how this works, it is possible to form galaxies without relying on any dark matter.

Here we go again.

For folk who were not avid readers of the UT thread, Electric Universe Model, proponents of the EU idea put forward Peratt's papers on spiral galaxies, as examples of quantitative work done in this ATM idea. Specifically, Peratt claimed to show that a pair of giant, inter-galactic, interacting currents would give rise to spiral structure in a body comprised of 'point particles, where the only forces acting were electromagnetic (per plasma physics), which spiral would have a rotation curve similar to those observed.

This claim was discussed, and to my mind, pretty comprehensively debunked (the relevant discussion is around p31-33 in the thread, late-March, 2005 onward; post numbers ~928 onward)). For example, in this post, I point out that the simulations do not produce two of the obvious structures of spirals - nuclei and central bulges. They also fail to show one of the structures most often touted by EU proponents as evidence for their idea - jets ('beams', in EU-speak)!

Do you have some new work by Peratt on the formation of (spiral) galaxies, that we have not already discussed, VanderL?

VanderL · #2 (**permalink**) 18-September-2005, 03:41 PM

What Peratt showed was "proof of principle", you haven't debunked his work at all, the comparison of real galaxies and simulations are as good as you can get; the only problem I see is lack of follow-up (funding maybe?).

Cheers.

VanderL · #3 (**permalink**) 20-September-2005, 03:12 PM

Quote:

Originally Posted by Nereid

Here we go again.

For folk who were not avid readers of the UT thread, Electric Universe Model, proponents of the EU idea put forward Peratt's papers on spiral galaxies, as examples of quantitative work done in this ATM idea. Specifically, Peratt claimed to show that a pair of giant, inter-galactic, interacting currents would give rise to spiral structure in a body comprised of 'point particles, where the only forces acting were electromagnetic (per plasma physics), which spiral would have a rotation curve similar to those observed.

This claim was discussed, and to my mind, pretty comprehensively debunked (the relevant discussion is around p31-33 in the thread, late-March, 2005 onward; post numbers ~928 onward)). For example, in this post, I point out that the simulations do not produce two of the obvious structures of spirals - nuclei and central bulges. They also fail to show one of the structures most often touted by EU proponents as evidence for their idea - jets ('beams', in EU-speak)!

Do you have some new work by Peratt on the formation of (spiral) galaxies, that we have not already discussed, VanderL?

Nereid, your dismissal of Peratt's work is not by any reckoning a "debunking", on top of that it is at least condenscending to assume that if you disagree with his paper, it amounts to anything else than your opinion. Where did you publish your peer-reviewed work that really "debunks" Peratt's model? There is no need for new work by Peratt to show this "proof of principle". It would be nice to see some follow-up work that goes into more detail, but if it isn't coming, it's not Peratt's fault, and his work stands to show it is possible to form galaxies without any dark matter involved. And that's without any EU claims to distract from the discussion about the shortcomings of BBT.

Cheers.

Nereid · #4 (**permalink**) 20-September-2005, 03:27 PM

Quote:

Originally Posted by VanderL

Nereid, your dismissal of Peratt's work is not by any reckoning a "debunking", on top of that it is at least condenscending to assume that if you disagree with his paper, it amounts to anything else than your opinion.

Yes, indeed; I over-stated the case. My apologies.

To set the record straight then: what, VanderL (or any other EU proponent), does Peratt's work on simulations of spiral galaxies show?

What are the limits of that work?

Please be sure to cite Peratt's claims, as well as your own. We will then be able to assess VanderL's claims:

Quote:

There is no need for new work by Peratt to show this "proof of principle". It would be nice to see some follow-up work that goes into more detail, but if it isn't coming, it's not Peratt's fault, and his work stands to show it is possible to form galaxies without any dark matter involved.

VanderL · #5 (**permalink**) 20-September-2005, 08:34 PM

Quote:

Originally Posted by Nereid

Yes, indeed; I over-stated the case. My apologies.

To set the record straight then: what, VanderL (or any other EU proponent), does Peratt's work on simulations of spiral galaxies show?

What are the limits of that work?

Please be sure to cite Peratt's claims, as well as your own. We will then be able to assess VanderL's claims:

Hah, apologies accepted and then you still want to argue the point. I concluded from Peratt's work that it is possible to form galaxies without having to include dark matter. If you think I overstated anything just read his papers and tell me different. If you want to discuss the specifics of plasma cosmology, there's other threads, I only brought it up here as a response to Cougar's pointed questions. Plasma cosmology is a viable option, but this thread is mainly concerned with the BBT failings, dark matter being one of those.

I don't see much response to dgruss23's posts about the problems for CDM that are recognized by many scientists. So I guess everyone agrees dark matter is a real problem which could ultimately prove fatal.

Cheers.

Nereid · #6 (**permalink**) 20-September-2005, 08:55 PM

Quote:

Originally Posted by VanderL

I concluded from Peratt's work that it is possible to form galaxies without having to include dark matter. If you think I overstated anything just read his papers and tell me different.

Given the rather confused state that some of the 'merged' topics are in, it might be a good idea if you could post a link to these here, anew.

Quote:

I don't see much response to dgruss23's posts about the problems for CDM that are recognized by many scientists.

All in good time.

Quote:

So I guess everyone agrees dark matter is a real problem which could ultimately prove fatal.

I rather doubt that. A more accurate statement would be something like "there are lots of open questions about CDM and its role in cosmology".

Cougar · #7 (**permalink**) 21-September-2005, 06:07 PM

I asked: Is this theory claiming that a long-range electromagnetic field is the thing that is keeping the galaxy from flying apart?... Is there any way you can show that this galactic action could "generate" such a strong EM field to be able to alter the orbits of very massive bodies? And not just alter. The effect must be huge. It's got to be 8 or 9 times the effect of gravity from all the stars and dust (and central black hole) that we know inhabit our galaxy.... So feel free to explain how big this field strength has to be and how such a massive EM field is generated throughout the galaxy and extending well outside its edges.

Quote:

Originally Posted by VanderL

Peratt's work showed how this works, it is possible to form galaxies without relying on any dark matter. The local field is not very strong, the difference is in the order of the Pioneer anomaly, maybe we already detected the field.

You seem to have ignored the content of my question. I'm not asking about the formation of galaxies, as it seems the work you cited addresses. I'm asking about how all the stars can remain in their orbits within most of the galaxies we currently observe. If the field you're talking about is "in the order of the Pioneer anomaly", then surely this would not be enough to hold all the galaxy's stars in their orbits, as above described. Right?

VanderL · #8 (**permalink**) 21-September-2005, 07:20 PM

Quote:

Originally Posted by Cougar

I asked: Is this theory claiming that a long-range electromagnetic field is the thing that is keeping the galaxy from flying apart?... Is there any way you can show that this galactic action could "generate" such a strong EM field to be able to alter the orbits of very massive bodies? And not just alter. The effect must be huge. It's got to be 8 or 9 times the effect of gravity from all the stars and dust (and central black hole) that we know inhabit our galaxy.... So feel free to explain how big this field strength has to be and how such a massive EM field is generated throughout the galaxy and extending well outside its edges.
You seem to have ignored the content of my question. I'm not asking about the formation of galaxies, as it seems the work you cited addresses. I'm asking about how all the stars can remain in their orbits within most of the galaxies we currently observe. If the field you're talking about is "in the order of the Pioneer anomaly", then surely this would not be enough to hold all the galaxy's stars in their orbits, as above described. Right?

You mean there is a difference between the formation of a galaxy and the orbits of it's individual stars? That's an interesting concept, could you explain how galaxies form without also accounting for the positions of individual stars (and other plasma, I might add)?

And no, the fields involved are in the order of the observed magnetic fields, it's the scale that does it.

Btw, if you want to talk about ignoring, you didn't answer some of my questions (and some of the other posters) and only respond to the point of the validity of an alternative model, instead the point I wanted to make is that dark matter as a concept can be thought of as a 70+ years old embarrassment for science (as admitted by respected astronomers) and possibly fatal to BBT.

Cheers.

TomT · #9 (**permalink**) 23-September-2005, 12:26 AM

[quote=Nereid]Here we go again.

For folk who were not avid readers of the UT thread, Electric Universe Model, proponents of the EU idea put forward Peratt's papers on spiral galaxies, as examples of quantitative work done in this ATM idea. Specifically, Peratt claimed to show that a pair of giant, inter-galactic, interacting currents would give rise to spiral structure in a body comprised of 'point particles, where the only forces acting were electromagnetic (per plasma physics), which spiral would have a rotation curve similar to those observed.

Nereid,
I have to add a correction here. Peratt's calculations on spiral galaxies included the full set of all relevant equations including gravity and all of Maxwell's equations. You can read it all on his web site. The claim that he considered electromagnetic forces only is incorrect. If you want references, let me know.
TomT

Cougar · #10 (**permalink**) 23-September-2005, 02:38 AM

Quote:

Originally Posted by VanderL

You mean there is a difference between the formation of a galaxy and the orbits of it's individual stars?

Uh, yeah. Sort of like the difference between a baby and a grown human. You see any difference there?

Quote:

Originally Posted by VanderL

That's an interesting concept, could you explain how galaxies form without also accounting for the positions of individual stars...

Are you dodging my question, VanderL? I'm not talking about galactic formation that occurred in the past. I am asking you to admit or deny that you hold the position that "electromagnetism" explains all of the flat rotation curves of galaxies that we currently observe and accounts for what most astronomers and astophysicists view as a whole lot of "missing" mass that isn't really "missing" because its gravitational effect, or what appears to be a gravitational effect, is clearly measured and verified. As previously mentioned, this "apparent gravitational effect" is roughly ten times the gravitational effect of all of the known stars and gas and dust within our galaxy, which amounts to, what, about 150 billion solar masses? So please explain how, apparently out of nowhere, you can generate electromagnetically the equivalent gravitational effect of 1.5 trillion solar masses in order to hold all of the stars in our galaxy in stable orbits around the galactic nucleus.

ChaByu · #11 (**permalink**) 23-September-2005, 04:09 AM

[quote=TomT]

Quote:

Originally Posted by Nereid

Here we go again.

For folk who were not avid readers of the UT thread, Electric Universe Model, proponents of the EU idea put forward Peratt's papers on spiral galaxies, as examples of quantitative work done in this ATM idea. Specifically, Peratt claimed to show that a pair of giant, inter-galactic, interacting currents would give rise to spiral structure in a body comprised of 'point particles, where the only forces acting were electromagnetic (per plasma physics), which spiral would have a rotation curve similar to those observed.

Nereid,
I have to add a correction here. Peratt's calculations on spiral galaxies included the full set of all relevant equations including gravity and all of Maxwell's equations. You can read it all on his web site. The claim that he considered electromagnetic forces only is incorrect. If you want references, let me know.
TomT

Absolutely right electromagnetic forces and gravity are taken into consideration but that seem volontary ingnored by the detractors of PU model.
here the plasma universe model for star formation
also scaled for galaxy formation proposed by Alfvén
http://members.tripod.com/~geobeck/frontier/bbang3.html

Quote:

The solar system, for instance, formed from the gravitational collapse of a vast gas cloud. As this cloud contracted as a result of gravity, it started spinning. If gravity were the only force involved, the process would have stopped there. The centrifugal force of the cloud would have resisted further collapse, with the solar system stabilizing as a diffuse cloud of gas, roughly twice its present diameter. But the solar system did form. Hannes Alfvén, the father of plasma cosmology, theorized that the inner part of the protostellar plasma cloud spun faster than the outer part, generating an electric current, "flowing out along the solar magnetic field lines, through the cloud and back to the sun at its equator" (p. 189). The interaction of the currents and magnetic fields caused the inner cloud to slow down, and the outer cloud to speed up, transferring angular momentum out of the system, and allowing further collapse.

By this mechanism, the early solar system lost 99.9% of its angular momentum, allowing the sun the collapse to the point at which it was able to ignite. The magnetic field action does not stop there, though. The sun, which represents over 99% of the mass of the solar system, retains only two percent of its angular momentum, while Jupiter has 70%, and Saturn has 27%. Two planets, which represent about a thousandth of the mass of the solar system, possess nearly all of its angular momentum (p. 188). In 1972, Alfvén and Gustaf Arrhenius developed a model of the early solar system in which self-pinched filaments swept through the dense protoplanetary plasma, their concentrated magnetic fields transferring angular momentum from the sun to the protoplanetary disk, pinching the plasma together into planets, which use the same process to form satellites (p. 209). The existence of planetary currents and filaments was confirmed in the sixties and seventies, when space probes detected them around Earth and the outer planets, exactly as Alfvén and his colleagues predicted (p. 45). This process may also be the key to solving a long-standing mystery: the origin of the moon. I propose that an analysis of the angular momentum of the Earth and moon will reveal whether the moon formed with the Earth, or was captured later.

Using the magnetic field model for solar formation, Alfvén made the leap to the galactic scale. In 1977, Alfvén and Per Carlqvist proposed that a protogalaxy behaves like a protostar, transferring away angular momentum and using filaments to form irregularities in the plasma (p. 209). The result is a galactic circuit, in which "...the entire galaxy acts as a disk generator, spinning in an intergalactic field. Currents flow inward on the plane of the galaxy, along the spiral arms, and out along the axis of rotation." (p. 211). Inside the spiral arms, smaller irregularities would form dense clouds, stellar nurseries like the Orion nebula. "In 1989, this hypothesis... was confirmed when scientists observed that the rotation axes of all the stars in a given cloud are aligned with the cloud's magnetic field" (p. 209). In other words, star clusters are just scaled up solar systems.

TomT · #12 (**permalink**) 23-September-2005, 04:41 AM

Quote:

Originally Posted by Cougar

Uh, yeah. Sort of like the difference between a baby and a grown human. You see any difference there?

So please explain how, apparently out of nowhere, you can generate electromagnetically the equivalent gravitational effect of 1.5 trillion solar masses in order to hold all of the stars in our galaxy in stable orbits around the galactic nucleus.

Hi Cougar,
I don't know how familiar you are with the Plasma Universe theories, but to understand this field accurately, you have to do some thorough, not cursory, homework. I will concede that the onus is on the PU proponents to convince you that what they propose is based on sound science and worth your time to read.
I would invite you to go to www.plasmauniverse.com and peruse the site as you feel inclined. There is a link to "Published Papers". Under the heading "Galaxies", I would highly recommend reading the 2nd and 3rd entries, Evolution of the Plasma Universe I and II. You will see in the 2nd paper that gravity forces, as well as electromatic, play their role in the formation of galaxies.
TomT

Nereid · #13 (**permalink**) 23-September-2005, 05:56 AM

Quote:

Originally Posted by TomT

I have to add a correction here. Peratt's calculations on spiral galaxies included the full set of all relevant equations including gravity and all of Maxwell's equations. You can read it all on his web site. The claim that he considered electromagnetic forces only is incorrect. If you want references, let me know.

Quote:

Originally Posted by TomT

Hi Cougar,
I don't know how familiar you are with the Plasma Universe theories, but to understand this field accurately, you have to do some thorough, not cursory, homework. I will concede that the onus is on the PU proponents to convince you that what they propose is based on sound science and worth your time to read.
I would invite you to go to www.plasmauniverse.com and peruse the site as you feel inclined. There is a link to "Published Papers". Under the heading "Galaxies", I would highly recommend reading the 2nd and 3rd entries, Evolution of the Plasma Universe I and II. You will see in the 2nd paper that gravity forces, as well as electromatic, play their role in the formation of galaxies.
TomT

Hi TomT.

It was those Peratt papers, published in 1986, which I reviewed, and commented on, back in the EU thread.

I checked; the simulation which Peratt ran is described in paper I; the results in papers I and II. The second paper contains the results VanderL appears to have had in mind ("Peratt's work showed how this [a long-range electromagnetic field that keeps a spiral galaxy from flying apart] works, it is possible to form galaxies without relying on any dark matter. The local field is not very strong, the difference is in the order of the Pioneer anomaly, maybe we already detected the field."). Although the second paper contains two sections which (briefly) consider gravity, the simulations were done using plasma codes (with no gravity).

The papers are also quite specific on galaxy formation and evolution; it might be an interesting exercise to compare the results of Peratt's simulations with more modern observational results, esp wrt galaxy evolution.

Perhaps a PU/PC/EU proponent has done further work, incorporating gravity into the Peratt plasma codes; if so, such work does not seem to be cited on the PU papers page.

Quote:

Originally Posted by ChaByu

Absolutely right electromagnetic forces and gravity are taken into consideration but that seem volontary ingnored by the detractors of PU model.
here the plasma universe model for star formation
also scaled for galaxy formation proposed by Alfvén
http://members.tripod.com/~geobeck/frontier/bbang3.html

I think I must have missed it, ChaByu - nothing on this page says that PUers have done any quantitative work on star and galaxy formation taking into consideration both electromagnetic forces and gravity. In particular, wrt galaxies, the same Peratt simulations as I discussed above (and referred to by TomT) seem to be cited as pinnacle of PU work.

ChaByu · #14 (**permalink**) 23-September-2005, 06:48 AM

Quote:

Originally Posted by Nereid

Perhaps a PU/PC/EU proponent has done further work, incorporating gravity into the Peratt plasma codes; if so, such work does not seem to be cited on the PU papers page. I think I must have missed it, ChaByu - nothing on this page says that PUers have done any quantitative work on star and galaxy formation taking into consideration both electromagnetic forces and gravity. In particular, wrt galaxies, the same Peratt simulations as I discussed above (and referred to by TomT) seem to be cited as pinnacle of PU work.

Probably what you are looking for
Advances in Numerical Modeling of Astrophysical and Space Plasma, A. L. Peratt, APSS 242, 1997 (3.3MB)

Advances in Numerical Modeling of Astrophysical and Space Plasma, Part II Astrophysical Force Laws on the Large Scale. A. L. Peratt, APSS 256, 1998 (2.1MB)

Advances in Numerical Modeling of Astrophysical and Space Plasma, Part II Astrophysical Force Laws on the Large Scale. A .L. Peratt, APSS 256, 1998 [Adobe annotated edition] (8.3MB)

Nereid · #15 (**permalink**) 23-September-2005, 09:06 AM

Quote:

Originally Posted by ChaByu

Probably what you are looking for
Advances in Numerical Modeling of Astrophysical and Space Plasma, A. L. Peratt, APSS 242, 1997 (3.3MB)

Advances in Numerical Modeling of Astrophysical and Space Plasma, Part II Astrophysical Force Laws on the Large Scale. A. L. Peratt, APSS 256, 1998 (2.1MB)

Advances in Numerical Modeling of Astrophysical and Space Plasma, Part II Astrophysical Force Laws on the Large Scale. A .L. Peratt, APSS 256, 1998 [Adobe annotated edition] (8.3MB)

Thanks.

Apart from the thoroughly mainstream parts (e.g. IPM, solar corona, aurorae; MHD and ISM studies), the first two papers (I've not read the third - again - yet) say nothing about quantitative work on star and galaxy formation being the results of interactions between interstellar/galactic currents, as well as both electromagnetic forces and gravity. In particular, wrt galaxies, the same Peratt simulations as I discussed above (and referred to by TomT) seem to be cited as pinnacle of EU work.

IOW, lots of good physics, and much of it quite unexceptional; but EU work does not seem to have been done.

Cougar · #16 (**permalink**) 23-September-2005, 01:42 PM

Quote:

Originally Posted by TomT

I don't know how familiar you are with the Plasma Universe theories, but to understand this field accurately, you have to do some thorough, not cursory, homework. I will concede that the onus is on the PU proponents to convince you that what they propose is based on sound science and worth your time to read.
I would invite you to go to www.plasmauniverse.com and peruse the site as you feel inclined.

Well, I've done plenty of homework in my time, and that is why the "plasma universe" and the "electric universe" theories appear to be so... ridiculous. But OK, I perused your site as I felt inclined. I didn't see anything about galactic dynamics or alternative explanations to galactic dark matter. The closest I saw was about the formation of the solar system, which I clicked on. The first sentence said

"Cosmogony, the study of the formation of planets, is perhaps one of the most researched topics in the Plasma Universe."

This is not a good start! Cosmogony is NOT the study of the formation of planets. If you can't get the very first sentence right, I don't have a lot of hope for the rest of the discussion.

Quote:

Originally Posted by TomT

You will see in the 2nd paper that gravity forces, as well as electromatic, play their role in the formation of galaxies.

Again, I am responding to criticisms of dark matter, which affects the dynamics of galaxies right now, not just during their formation. I cannot see how electromagnetism can come anywhere close to explaining current galactic dynamics, and all I see are the EU and PU proponents dodging the issue.

VanderL · #17 (**permalink**) 23-September-2005, 03:28 PM

Quote:

Originally Posted by Cougar

Uh, yeah. Sort of like the difference between a baby and a grown human. You see any difference there?

Are you dodging my question, VanderL? I'm not talking about galactic formation that occurred in the past. I am asking you to admit or deny that you hold the position that "electromagnetism" explains all of the flat rotation curves of galaxies that we currently observe and accounts for what most astronomers and astophysicists view as a whole lot of "missing" mass that isn't really "missing" because its gravitational effect, or what appears to be a gravitational effect, is clearly measured and verified. As previously mentioned, this "apparent gravitational effect" is roughly ten times the gravitational effect of all of the known stars and gas and dust within our galaxy, which amounts to, what, about 150 billion solar masses? So please explain how, apparently out of nowhere, you can generate electromagnetically the equivalent gravitational effect of 1.5 trillion solar masses in order to hold all of the stars in our galaxy in stable orbits around the galactic nucleus.

Cougar, please don't play the indignancy game here, I answered your questions. I don't see any difference between the evolution of a galaxy over appr. 10 billion years, as Peratt modelled and a fully grown galaxy, as you seem to envision. (He also modelled irregular galaxies, something current models do by making random galaxy shapes "collide" and see what happens). I'll let the "out of nowhere" remark pass, as the Universe clearly didn't materialise out of nowhere.
More to the point, if you want to discuss Plasma Cosmology, it's better to do it in another thread, because this thread is more about the shortcomings of BBT, like the Lerner paper I linked to earlier.

Cheers.