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General Relativity Resolves this Problem? (A Question from the Unwashed Masses :-)

Does the physics community consider the solution proposed below (paper by Cooperstock & Tieu) as a promising one to the galaxy rotation problem? I had read about this, but was surprised this entry made no substantive discussion of this recent proposal. I am not a physicist so I am hoping some kind but knowledgeable soul will give us some perspective on this work. "General Relativity Resolves Galactic Rotation Without Exotic Dark Matter" F. I. Cooperstock & S. Tieu Submitted to the Astrophysical Journal, 23 pages, 7 figures, 4 tables http://arxiv.org/PS_cache/astro-ph/pdf/0507/0507619.pdf

(a previous untitled discussion)

"scientists simply assumed that the rotation curve was flat because of the presence of a large amount of matter outside the galaxies"

Are you sure this is correct? How can the presence of matter outside a galaxy affect rotation speeds with?. I thought dark matter was postulated to exist within a galaxy but not all concentrated at the centre as Newtionian models suppose. However I am not confident enough that I am correct to make the change to the page without further research. Watch this space! Theresa knott

You're right, I'm trying a different wording: "a large amount of matter surrounding the visible part" - At18 21:46 Apr 28, 2003 (UTC)

It would be nice to post the modeled mass distribution in the galaxy that produces the A velocity curve - e.g., don't you need an assumed mass distribution to generate that curve? And wouldn't different assumed mass distributions generate different velocity curves. Is there a mass distribution that it is reasonable or obvious to use to generate the expected velocity curve?

This page is a complete mess. I'm taking a hose to it. -- Decumanus 18:20, 12 Feb 2004 (UTC)

Cleaned up

The page was a disaster. I have cleaned it up. 67.172.158.8 17:23, 24 Dec 2004 (UTC)

Elliptical orbits

One thing that I have never seen is an explanation of the galactic rotation curve that also explicitly takes into account the theory that the spiral arms are not in fact coherent but are a construct of the elliptical orbits of the stars that make them up, as explained by Image:Spiral galaxy arms diagram.png. The implication of this is that a star in a spiral arm is near the aphelion end of the ellipse, and so is going more slowly than a star on a circular orbit at that distance would be. If the ellipses themselves are turning and giving the illusion of the spiral arms rotating evenly, then the discrepancy could disappear. It seems unlikely that this has been overlooked, but I'd be interested to see a discusson that includes this aspect. — PhilHibbs | talk 18:41, 23 Feb 2005 (UTC)

Velocity vs Speed

The vertical axis of the graph really should be "Speed". I know that "Velocity" sounds more scientific, but velocity is a vector and that's not being represented on the graph, but only the magnitude, and the magnitude component of velocity is "speed". -- Ch'marr 15:29, 10 October 2005 (UTC) (the pedant)

Galactic Rotation curves

I recently heard that the speed of the outermost stars in a galaxy is determined by the mass of the central black hole. This results from the conditions required for the quasar that formed the galaxy to become non-active. And so is determined not by conditions now but by those in the past. Could not the whole rotation curve be due to processes like this? Perhaps combined with those of General Relativity as in the paper referenced above? Perhaps this could also help in elimination dark-matter from the affect.

(I am not a physicist so I am presenting this question for criticism.)

Alan Stafford

alan_stafford@btinternet.com

Plasma comology view of galaxy formation

I've restored the paragraph on plasma cosmology's view of galaxy formation. This is a published peer reviewed theory, and directly relevant to this article. I notice that the "redundant" paragraph on MOND was not removed, even though it also has an article of its own. --Iantresman 12:43, 26 February 2006 (UTC)

A five minutes perusal of the plasma cosmology talk page shows that plasma cosmology is a highly controversial subject. A subject, that for some bizarre reason, you want to promote at every opportunity. Lets keep the fight contained, okay? The MOND paragraph gives an appropriate, brief summary of that alternative. Nonsuch 16:27, 26 February 2006 (UTC)

Also, "minority" is not synonymous with "small minority". The first means less than 50%, the second means (in this context) about 0.01%. Nonsuch 16:55, 26 February 2006 (UTC)

It's your opinion that it is "highly controversial", and even then, it doesn't make a peer reviewed theory not worthy of mentioning; It's not for you or I to judge. The paragraph is factually accurate, and verifiable. Unless you have some peer reviewed paper that shows any inaccuracies in the Peratt's work (which has been around for some 20 years), I see no reason for it to go. Even aspects of dark matter are still considered controversial --Iantresman 17:45, 26 February 2006 (UTC)

In a sense, you are correct, of course. Plasma cosmology is really only a controversial subject here on the wikipedia. Out there in the real world, the vast majority of real cosmologists simple ignore it. It is, at best, a fringe science, a speculative alternative that hasn't mustered the necessary evidence to become mainstream. It does not deserve more than sentence or two on this page. And yes, of course dark matter is speculative as well, and will remain so until a better theory is found or the nature of dark matter is determined. At present, it simple the best, most parsimonious explanation of observation. Nonsuch 18:20, 26 February 2006 (UTC)

Sigh. –Joke 18:46, 26 February 2006 (UTC)

Peratt's papers are hardly cited at all by anyone, which shows his theories are not significant or widely believed. A brief mention of them more than suffices here. Worldtraveller 18:56, 26 February 2006 (UTC)

Right. Just because a paper is published doesn't mean that it isn't junk. Iantresman , you're referencing a 20 year old paper that has a grand total of 4 citations (according to Google Scholar), 3 of them self citations. Over the past 20 years Peratt's work has been judged by his peers to be utterly uninteresting. Nonsuch 19:03, 26 February 2006 (UTC)

A paper which is not published in an astrophysics journal. Incidentally, the number of citations is actually somewhat higher, at 15. In general, it is better to look for these things on ADS than Google scholar. That doesn't, however, invalidate the obvious points Nonsuch is making. The citation counts for MOND are much higher. The plasma cosmology is an extreme minority position. –Joke 19:28, 26 February 2006 (UTC)

I removed the statement: "simulations using this theory do not provide quantitative agreement with observation, and this idea has not been pursued by cosmologists." because it is (a) completely unsubstantiated (b) and it is pursued by plasma cosmologists.

It is quite clear how your version of "science" operates. First make sure people adhere to the scientific method, and if by chance they do, YOU decided whether it is significant. A quick looks at the ADS database reveals:

• 14 references by Peratt and co-authors on keyword=galaxy
• Around 50 citations in total (excluding those by Peratt), though some of these may be duplicates.
• 100s of articles on "plasma universe/cosmology"-related subjects by authors such as Alfven, Carlqvist Fälthammar, Lerner, and Peratt. This is not insignificant. --Iantresman 20:37, 26 February 2006 (UTC)

Incidentally, a number of Peratt's papers ARE published in astrophysics journals (Astrophysics and Space Science), including:

• Advances in Numerical Modeling of Astrophysical and Space Plasma (1997)
• Electric space : evolution of the plasma universe (1996)
• Plasma and the Universe: Large Scale Dynamics, Filamentation, and Radiation (1995)
• Introduction to Plasma Astrophysics and Cosmology
• On the evolution of interacting, magnetized, galactic plasmas (1995)

It is quite clear that either Astrophysics and Space Science made a mistake 5 times in row, or their idea of peer review and lack of bias is different to yours. --Iantresman 20:44, 26 February 2006 (UTC)

Getting published is a very low threshold. It only means that the paper is reasonable coherent and not obviously wrong. Also, journals vary wildly in their standards. I am not particularly familiar with Astrophysics and Space Science, but it seems that their impact factor (a rough measure of how good the research in the journal is, on average) is rather low. But this is all besides the point. The current revision seems reasonable. Nonsuch 21:08, 26 February 2006 (UTC)

Can we stop it with the hysteria? I'm not some kind of zealous censor whose quest is to expurgate Misplaced Pages of any mention of non-standard cosmological models. –Joke 21:31, 26 February 2006 (UTC)

Joke, I'm not replying specifically to you, but to those who claim "proofs" of falsifiability such as "Peratt's papers are hardly cited at all", and, "using this theory do not provide quantitative agreement with observation".

And for what it's worth, I found 366 references to MOND, about two-thirds as many as there are on plasma universe/cosmology. --Iantresman 00:32, 27 February 2006 (UTC)

MOND is of questionable legitimacy on this page as it represents an extremely small minority in the explanation category. Plasma cosmology, not taken seriously by cosmologists, does not belong here especially considering Perratt's work has not been repeated by anyone else. A single modle that purports to solve a problem is not worth including on this page lest it be polluted with many different suggestions. --ScienceApologist 14:54, 27 February 2006 (UTC)

It's the scientific inquisition yet again. At least you're predictable. I don't give a fig what YOU think about MOND, or what you THINK other cosmologists think about plasma cosmology. YOUR censorship of factually acurate and verifiable statements shows your complete lack of understanding of Neutral point of view. I suggest your read the Misplaced Pages NPOV section on Information_suppression.

If you want to include a verifiable peer-reviewed comment on Peratt's work, then that's fine, but just because your range of reading does not extend to plasma cosmology, gives you no right to remove peer-reviewed material. As I mentioned above, if you'd bother to read it, there are more references to plasma universe/cosmology, than there is to MOND.

Three other editors were content with a sentence mentioning plasma cosmology, and although I expect they were not entirely happy with it, were big enough to let it stand. --Iantresman 17:22, 27 February 2006 (UTC)

Plasma cosmology as an extreme minority does not bear exposition according to undue weight. As such I've moved it to parenthetical mention along with other points. POV-creep and cruft of any kind is unacceptable here at Misplaced Pages. Since there are almost no sources written about the galaxy rotation problem itself that mention the alternatives, it is questionable whether their mention here in the encyclopedia is reasonably sourced at all, Ian Tresman's uninformed opinion notwithstanding. --ScienceApologist 19:28, 27 February 2006 (UTC)

Plasma cosmology as only an extreme minority in your eyes (ie, your POV), and insults the dozens of researchers who have published HUNDREDS of peer reviewed papers.That plasma cosmologists have a theory that they believe explains the galaxy rotation problem, is NOT a point of view; that is a verifiable fact. That has NOTHING to do with my opinion, or anyone else's. And whether other articles mention alternative theories is irrelevent. My "uniformed opinion" is also irrelevent, but I have peer reviewed citations that makes our opinions worth squat. --Iantresman 23:50, 27 February 2006 (UTC)

At the end of the day the simple fact is, plasma cosmology is a fringe theory with very little currency in cosmology today, and should be treated as such in the article. Worldtraveller 23:53, 27 February 2006 (UTC)

And the flat earth isn't fringe, and get three times the length of the entire article? This is not a competition. It may be fringe, but it still deserves explanation, otherwise your do a disservice to those who are interested. I'm sure we could both find 10,000 articles on Misplaced Pages we would never miss, and wouldn't care if they weren't included at all. But I don't tell you what articles should and should not be included, and you should give plasma cosmologist same respect... you're not going to "fill up" Misplaced Pages. --Iantresman 00:03, 28 February 2006 (UTC)

Plasma cosmology has its own article, very easy to find, an ideal place to discuss the theory and its relevance to modern cosmology. Here, in this article about the galaxy rotation problem, it deserves only a very small mention because it's a fringe theory and I really think it would be a good idea for you to stop trying to inflate its importance. Earth doesn't make a big deal of the flat earth theory, does it? Worldtraveller 00:28, 28 February 2006 (UTC)

I'm not trying to inflate its importance. I'm trying to explain it; if that takes a paragraph, then so be it. That you won't let other people read about HOW the plasma cosmology theory of galaxy formation does not have a galaxy formation problem, in an article on the subject, is beyond me. Oh yes, "extreme minority fringe" implies that theory can't even be plausible, and readers can't find out for themselves; the scientific method in action! --Iantresman 00:59, 28 February 2006 (UTC)

Good grief. Ian, you clearly have a personal agenda, (Citation: You're vanity page.) You're not doing anything to improve this article. Please go away. Nonsuch 01:32, 28 February 2006 (UTC)

You managed to draw that conclusion from my interests on my vanity page? See ScienceApologist for an agenda from a real scientist. To improve the article, I'm providing verifiable citations to various peer review material. What are you doing, calling on your friends that Mcarthyist-type ideas are spreading. --Iantresman 08:08, 28 February 2006 (UTC)

Ian, perhaps you shouldn't be casting stones at people for "calling on your friends" when you did the same at the Halton Arp forum regarding the redshift page. --ScienceApologist 19:19, 28 February 2006 (UTC)

Perhaps, but I'm also providing some verifiable substantiation to my criticisms. --Iantresman 19:48, 28 February 2006 (UTC)

I removed the following line until a verifiable citation could be found:

• None of these alternative are consdiered by the astronomical community to be as convincing as the dark matter model.

--Iantresman 19:50, 28 February 2006 (UTC)

I have removed this line again, as I don't think the verifiable statement provided implies this.

• This is a BBC report giving a reporter's opinion.
• The report mentions MOND, but not plasma cosmology, quasi-steady state cosmology, nor the ideas advocated by Halton Arp.
• And I can find no mention of the "majority of the astronomical community"; and even if one person believed this to be the case, then it's one person's opinion at best.

--Iantresman 19:19, 25 March 2006 (UTC)

The report is on the current state of dark matter research. It is a verifiable source of someone in the popular media who is looking into the opinions and ideas of the astronomical community. Removal of it was unjustified especially considering the factual nature of the statement. --ScienceApologist 20:28, 30 March 2006 (UTC)

Show me where the report mentions "plasma cosmology" (or even plasma for that matter), and Arp. Provide some VERIFICATION for a change --Iantresman 20:55, 30 March 2006 (UTC)

You need to learn what verifiable means. Just because you don't understand doesn't mean you can impose your own views on the rest of Misplaced Pages. --ScienceApologist 21:50, 30 March 2006 (UTC)

Since you refuse to provide me with a suitable verification, or show me where the current citation refers to plasma cosmology or Arp's work, I have tagged the statement with the ((citation required)) tag. If you are unable to comply, I shall take the necessary course to have your statement removed. --Iantresman 23:56, 30 March 2006 (UTC)

Both references mention dark matter and MOND, and none of the other theories. Neither references verify the statement that "None of these alternatives are considered..." when just one alternative is mentioned in the references --Iantresman 21:54, 31 March 2006 (UTC)

MOND is the most positively received alternative. The other ideas are not addressed because they aren't even considered by the authors (LESS plausible). You are on the POV-warpath. Statement is verified. If you have further problems, take it to RfC. --ScienceApologist 22:50, 31 March 2006 (UTC)

Sorry, your opinion is not substantiated by the references, unless you're suggesting that the references contain "dark verification"... we can infer that's what the authors imply so it must be there? Even pseudoscience is more credible than that. --Iantresman 14:51, 1 April 2006 (UTC)

Ian, it is your opinion which is not substantiated by references. Please provide a reference to someone who claims that any of the other ideas are addressed as frequently as MOND in the astronomical community. The onus is on you to find such a reference as proving a negative is hardly possible. --ScienceApologist 22:17, 1 April 2006 (UTC)

The statement is YOURS, it is not mine. The onus is on you to provide verification, and the references you gave do not. Both references mention dark matter and MOND, and no other theories. You can not infer anything about any other theory from them. Your statement is the very first on the list in the section on : "asserting claims which cannot be verified", and yours is not. --Iantresman 10:17, 2 April 2006 (UTC)

The verification is provided. Your objection stems from a request to prove a negative. --ScienceApologist 14:23, 2 April 2006 (UTC)

RfC: The Galaxy rotation problem: Alternative theories

I would like the article to mention a couple of other theories (eg. plasma cosmology, Arp/Narlika's work), that specifically address the Galaxy rotation problem on the grounds that they meet Misplaced Pages's "three content-guiding policies" (Verifiability, NPOV, No original research):

• They meet Misplaced Pages's policy on verifiability, in that there are peer-reviewed papers on the subject (and hence would not count as original research)
• They exceed Misplaced Pages's criteria on "Undue weight" in that prominent adherents can be named (obviously not by everybody, but how many people can name leading scientists in any specialised field?)
• And obvously we can describe such theories in a neutral style, thus meeting Wiki's policy on neutral point of view.

I also note that:

• We are not short of space, and perhaps a paragraph of text on each theory is not excessive.
• This article is the place to mention theories that directly address the Galaxy rotation problem
• We already mention MOND, and something to do with general relativity, though the latter is unattributed, and unexplained. We also mention "non-standard cosmologies, but with no explanation.
• We are not condoning other theories, merely noting that there are other theories.

Please indicate whether you Support or Oppose together with a short comment or qualification, and sign and date your entry. --Iantresman 19:27, 1 April 2006 (UTC)

Support (as proposer) for the reasons described above. --Iantresman 19:27, 1 April 2006 (UTC)

Object Alternative ideas should be expounded upon on their respective pages. POV creep needs to be kept at a minimum. Commensurate with their importance, alternative non-mainstream ideas are reported on in this article. --ScienceApologist 22:19, 1 April 2006 (UTC)

Object. I don't see any problem with the single-paragraph listing already present in this version of the page. A paragraph of text on each theory is definitely excessive, and would leave the impression of undue significance even if flagged as not supported by most astronomers. --Christopher Thomas 05:17, 4 April 2006 (UTC)

• Isn't the "impression of undue significance" all down to the wording/style, and writing the information in a neutral point of view? NPOV policy says that "the editors of Misplaced Pages, trust readers' competence to form their own opinions". --Iantresman 10:05, 4 April 2006 (UTC)

Support of course, the problem in the article name begs of you to add them! It will be better to start with a section called Alternate theories, and make subsections as needed, though. Karol 08:35, 4 April 2006 (UTC)

Object. The current paragraph is a fine summary of alternatives. And, despite another dozen edits, the main focus of the article, the Galaxy Rotation Problem, hasn't been improved at all. Nonsuch 19:52, 4 April 2006 (UTC)

But the last paragraph says absolute NOTHING about some of the other alternative theories, and doesn't even name them --Iantresman 21:00, 4 April 2006 (UTC)

It names and links several credible (If not successful) alternatives. I think what you meant to say is "the last paragraph doesn't mention or link to my pet fringe pseudoscience, which I try to make look legitimate and mainstream by adding references all over the wikipedia"? At least from my POV that's what your POV looks like. Nonsuch 22:43, 4 April 2006 (UTC)

Misplaced Pages's policy on Verifiability does now allow us to promote our own points of view, and the policy on No original research prevents us from promoting our own pet theories, even if we supplement it with vaguely relevant references. However, Wiki recognises that even theories that you or I might not have heard of, is valid material for an encyclopedia, so says Jimbo Wales in Jan 2004 . Alternative peer-reviewed theories fall into this category, no matter what your opinion, or mine may be on their veracity. As I mentioned earlier, "the editors of Misplaced Pages, trust readers' competence to form their own opinions". --Iantresman 23:41, 4 April 2006 (UTC)

Object. The article already mentions alternatives to the mainstream view. IMO the Misplaced Pages community needs to shape up its coverage of mainstream science, in preference to trying to describe in great detail every last idea from fringe science (or even worse, outright crankery). Balanced, fair, and comprehensive coverage of mainstream science is crucial if WP is to succeed in serving its reader well by offering to the world a free on-line up-to-date and accurate universal encyclopedia. Extensive coverage of fringe and crank proposals is irrelevant and in fact harmful to the mission of Misplaced Pages. Such ideas may sometimes deserve a brief mention (e.g. if they have been widely publicized in print media). This particular case is a "no-brainer" because Ian himself operates a number of websites presenting the views of Arp and others. Therefore it seems to me that WP need only mention alternatives and provide a link (one should suffice) to a partisan website presenting the fringe ideas in detail. Which what this and related articles already do.---CH 22:05, 5 April 2006 (UTC)

• (1) Wiki policy says that we should "represent views fairly and without bias" It does not say that we present only mainstream views, nor the scientific point of view . (2) We aren't trying to describe in great detail, every last idea; we are trying to summarise some peer-reviewed theories. (3) Jimbo Wales himself says that fringe or obscure theories are important (4) Crank proposals do no harm if they are described neutrally, though it does not apply to this proposal. (5) There is no such Wiki policy requiring ideas to be widely publicized in the media; encyclopedias teach people what they might otherwise not find in the media (6) There is no such Wiki policy in which consensus is determined by the nature of Web sites that certain editors run (was this a serious reason?) (7) Why would we link to a "partisan website" in preference to providing peer reviewed citations?
• Did any of your reasons hold up to scrutiny? --Iantresman 23:39, 5 April 2006 (UTC)

Ian, not including alternative on this page does not preclude including alternatives in Misplaced Pages in general. Fringe ideas such as the ones you propose explaining in greater detail in the article can and should be relegated to pages devoted to them. POV-creep is not tolerated in Misplaced Pages, which is basically what you are advocating at this point. --ScienceApologist 01:01, 6 April 2006 (UTC)

(1) I find no Wiki policy definition on "fringe", but there is clear definition of "significant minority": that is, being able "to name prominent adherents" ; references allows us to do this (and it is verifiable) (2) I find no Wiki policy on "POV creep" let alone its tolerance (3) Wiki NPOV policy on Information suppression clearly describes subjects written in an "unfair manner": "Entirely omitting significant citable information in support of a minority view, with the argument that it is claimed to be not credible." --Iantresman 07:26, 6 April 2006 (UTC)

As this is not strictly about the article and is rather about Wikiphilosophy, I have continued the discussion at Misplaced Pages Talk:Neutral point of view#Undue weight and prominent adherents --ScienceApologist 13:53, 6 April 2006 (UTC)

Citations required

I'd like two citations please:

1. For the general relativity theory on the Galaxy rotation problem
2. That there is more than one non-standard cosmologies (the text says "various non-standard cosmologies ) theory on the Galaxy rotation problem

--Iantresman 09:16, 6 April 2006 (UTC)

I removed reference to the first point since it was subsequently contradicted and is now abandoned even by its authors.

I wouldn't object to removing the sentence about non-standard cosmologies altogether. If you are looking for another nonstandard explanation other than the junk from plasma cosmology, check out the various ideas promoted by Halton Arp. He has his own pet explanation. --ScienceApologist 14:05, 6 April 2006 (UTC)