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Space Science

New Theory Challenges Need For Dark Matter 302

New submitter elsurexiste writes "An Italian Physicist came up with a strange way to explain anomalous galactic rotations without dark matter, instead relying on the gravitational effects of faraway matter. The article explains, 'Conceptually the idea makes little sense. Positioning gravitationally significant mass outside of the orbit of stars might draw them out into wider orbits, but it’s difficult to see why this would add to their orbital velocity. Drawing an object into a wider orbit should result in it taking longer to orbit the galaxy since it will have more circumference to cover. What we generally see in spiral galaxies is that the outer stars orbit the galaxy within much the same time period as more inward stars. But although the proposed mechanism seems a little implausible, what is remarkable about Carati’s claim is that the math apparently deliver galactic rotation curves that closely fit the observed values of at least four known galaxies. Indeed, the math delivers an extraordinarily close fit.' As usual, these are extraordinary claims that divert from the consensus, so keep a healthy skepticism. The paper is available at the arXiv (PDF)."
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New Theory Challenges Need For Dark Matter

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  • by Sebastopol ( 189276 ) on Monday December 05, 2011 @04:55PM (#38271486) Homepage

    faster than light neutrino measurements?

    revolutionary-yet-pseudo-sciency sources of energy?

    and now dark matter challenges?

    coincidence or what?

  • by Anonymous Coward on Monday December 05, 2011 @05:07PM (#38271690)

    faster than light neutrino measurements?

    revolutionary-yet-pseudo-sciency sources of energy?

    and now dark matter challenges?

    coincidence or what?

    They'll do anything, absolutely anything, invent any figment, totally divorce the mathematics from natural philosophy, propose strange exotic forms of matter never observed, and claim their existence is "proven" because they have a favorite explanation among multiple explanations not requiring strange exotic forms of matter. They will do all of this, and more, to avoid admitting that "million degree gas" is conductive plasma and there is electricity in space and its attractive force is linear instead of following an inverse-square law, totally eliminating the need for any dark matter.

    Both require some kind of leap of faith. Conventional leap of faith: this strange unseen matter exists and interacts gravitationally but somehow isn't available on Earth, cannot be created or observed or studied in a lab, and is proposed to exist merely to fix a broken theory that never predicted its existence but can't get the expected results without it (Karl Popper spins in his grave...). Electrical leap of faith: electrical processes explain the lack of mass through the electric force which is many orders of magnitude stronger than gravity and is more effective at long distances and is the only logical explanation for light-years-long jets of matter (Birkeland currents), can be observed in any laboratory with modest equipment and is known to scale both up and down, and through processes not yet understood there is enough charge separation in the Universe to provide the potential difference to cause these circuits to flow.

    Or they can keep getting surprised, shocked, and amazed when they keep discovering celestial objects not predicted by their theories.

    I wonder how long it will be before science is forced to throw out dark matter and embrace electrical effects. Ten years? Twenty? It definitely won't be the first time an idea was long ridiculed before the consensus collapsed under its own weight and was later found to be valid and embraced. They call it a paradigm shift. It only happens this way because of a lot of stubborn bastards who chase pet theories and grant money and don't teach new students about alternative theories. Halton Arp's compilation of galaxies with highly redshifted quasars _in front of them_ and _physically connected to them_ alone should have made them reconsider, but instead he is ignored because he doesn't fit the orthodoxy. I thought science was supposed to be different from religions with their orthodoxies and heretics and apostates?

  • by thegreatemu ( 1457577 ) on Monday December 05, 2011 @05:15PM (#38271792)

    Disclaimer: I do experimental searches for dark matter for a living, so I may be biased in my judgement of these types of papers that crop up so often. There was a similar paper a few weeks ago from someone claiming that quantum vacuum polarization could account for dark matter PhysOrg link [physorg.com].

    The issue with both of these explanations, is that they only address galactic rotation curves. Those are among the first and easiest to explain indications of the need for something like dark matter, but are not the strongest by a long shot. For instance, this guy's explanation can't explain things like the famous Bullet cluster [wikipedia.org], nor can they explain the evolution of structure formation or the spectrum of fluctuations in the cosmic microwave background [nasa.gov] which, in the field, are considered much stronger constraints.

    The Cold Dark Matter (CDM) theory of cosmology fits all of the astrophysical measurements reasonably well, and has a nice tie-in to supersymmetric particle physics, which is one of the current leading theories. No one in the field will take any new theory seriously until it can reproduce ALL the phenomena at least as well as the current model (which of course is exactly how the scientific process is supposed to work!)

  • by quax ( 19371 ) on Monday December 05, 2011 @05:18PM (#38271868)

    This is based on Einstein's field equation using perturbation theory to construct a solution for the examined case.

    My bet is on general relativity once again delivering the goods. Quite a strike against the case for dark matter.

  • by Daniel Dvorkin ( 106857 ) on Monday December 05, 2011 @05:28PM (#38272032) Homepage Journal

    Seriously, is that the most you can add to the conversation is a cheap shot at religion?

    It wasn't a shot at religion, it was a shot at religious fanaticism. There's a difference, and pretending otherwise is disingenuous at best.

    I will agree that if such a claim is made it should be picked apart but can we just hold off the hostilities until it happens? For once?

    Hostilities were opened a long time ago. Your objection makes as much sense as saying to the captain of a US Navy ship, "I agree that if that Japanese ship over there shoots at us, we should blow them out of the water, but can we just hold off the hostilities until in happens?" in 1943.

  • by Anonymous Coward on Monday December 05, 2011 @05:32PM (#38272106)

    A religious rant, condemning other theories as inadequate, antiquated, and conforming to orthodoxy. On the internet too. Wow, who would have anticipated that?

    ... a rant that explains why the writer believes one theory to be better than the prevailing one by reviewing the merits of both.

    I know it's trendy to just look down your nose and condemn something without actually explaining what's wrong with it and why you disagree, and certainly it's trendy to avoid setting a better example by taking a position yourself that doesn't have the qualities you're complaining about... but don't you feel like a bitch when you do things this way? No insult intended, I mean "bitch" as in "bitching" as in completely non-constructive whining that doesn't fix or challenge or change anything.

    If you think the Electric Universe theory is invalid, or that the conventional theories with their ad-hoc explanations and retroactive revisements to deal with failed predictions are better, or that the scientific censorship encountered by Arp and others who were denied telescope time and denied publishment in peer-reviewed journals (that certainly could find any flaws in their theories consistent with the entire purpose of peer review) is the right way to handle dissent in a supposedly scientific establishment ... feel free to explain why. Take your own position. Show why the previous one is lacking.

    Be at least slightly respectable by bringing something to the table. Try it on for size.

  • Show us the math (Score:5, Interesting)

    by Fujisawa Sensei ( 207127 ) on Monday December 05, 2011 @05:53PM (#38272462) Journal

    Just show the math and how it correctly models modern astronomical data.

    I'll give you a hint, it doesn't even come close.

  • by HiThere ( 15173 ) <charleshixsn@ear ... .net minus punct> on Monday December 05, 2011 @06:17PM (#38272784)

    Somehow this argument sounds like the argument for continental drift before plate tectonics.

    OTOH, I note that the another comment denies that the mathematical fit is all that good. This isn't really convincing, as I heard similar denials of continental drift before a plausible mechanism was discovered.

    Still, if that it so you can expect it to continue to be rejected in a way that seems to you unreasonable UNTIL you come up with a plausible mechanism (for charge separation?). Personally I'd look at friction of intestellar gasses around the ejection plumes from black holes. Friction is well known for causing charge separation between, e.g., fur and glass. Now you've got to come up with your analogs to fur and glass...or come up with some other mechanism. But until you provide a plausible mechanism, this theory will be rejected without reasonable examination. Expect it.

  • by Bigby ( 659157 ) on Monday December 05, 2011 @06:21PM (#38272838)

    I've never believed in dark matter or dark energy. Physicists made it up to explain something that could not be explained by our current theories. The fact that they needed to be made up shows that our current model of the universe is wrong. It is patchwork science. It may work for now, but the more patches you add, the further you will get from the real truth.

  • by khipu ( 2511498 ) on Monday December 05, 2011 @06:23PM (#38272874)

    * Lack of MACHO gravitational lensing

    The MACHO-based argument is that there can't be enough of those objects around in order to explain galactic rotation. But this paper, in effect, says that you don't need them. So that observation seems consistent with this paper.

    * Existence of unexpected gravitational lensing in Bullet Cluster.

    The Bullet Cluster result shows that some form of unobservable matter exists. But we already know that: brown dwarfs, rogue planets, etc.: that kind of "dark matter" has been observed, just not in the amounts to explain galactic rotation.

    It is not surprising that somewhere in the universe, you might get very large clusters of such objects. The bullet cluster might just be composed of such objects. And at those distances, you couldn't observe baryonic dark matter. In fact, if you rip out most of the hydrogen from a cluster, it is perhaps not surprising that you end up with a lot of cold, dark lumps of baryonic matter.

    * CMBR measurements * and more.

    You have to separate explaining observations from testing hypotheses. CMBR measurements can be explained within the framework of non-baryonic dark matter. But that does not necessarily imply that they provide evidence for non-baryonic dark matter, since there are many other possible explanations.

    I'm not saying that this paper is true or not. But if you want to argue against it, you need to sharpen your arguments.

  • Re:Wow. (Score:5, Interesting)

    by jd ( 1658 ) <imipak@yahoGINSBERGo.com minus poet> on Monday December 05, 2011 @08:16PM (#38274400) Homepage Journal

    Not sure about the summary, but the paper is extremely simple. I'll summarize it:

    It is commonly assumed that galaxies are evenly distributed. This would mean that if you picked any galaxy at random, you could pick other galaxies whose gravitational pull totally balanced out the effect of the first one. So, overall, no distant galaxy would ever affect anything.

    What is observed is that galaxies are NOT evenly distributed. There is, indeed, left-over gravitational pull. Provided the distribution of galaxies is self-similar (which is what they mean by "fractal", since "fractal" itself has no meaning here) AND a few other constraints are valid, THEN the left-over gravitational pull would be enough to explain the rotation of the stars and gasses within the galaxy. The author's analysis of the galaxies over a relatively nearby region of space suggests to him that the distribution is indeed self-similar.

    (Summary off, analysis on)

    Is this a new theory? As a replacement for Dark Matter, yes. In any other context, no. Shepherding moons/asteroids dominate our own solar system, creating a dynamic that would be utterly unstable without them. Shepherding galaxies and super-galaxies is a new one, but if the physics is observed in other systems then the physics must be considered sound. The only question I see here is whether the distribution of galaxies is indeed self-similar. If it isn't, the theory is wrong. If it is, then dark matter - as it is currently understood - must be wrong because you now have left-over gravity and you have to alter the dark matter theory to allow for it.

    Doesn't the dark matter theory fit things well as it is? No it doesn't. Dwarf galaxies and globular clusters exhibit NONE of the signs assumed to indicate the presence of dark matter. Some don't have high-speed rotation at all. Dark matter theory cannot explain either of these and the usual answer is to say that dark matter "isn't uniform" without ever explaining why it should be missing only with certain classes of structure and not others. It's actually much easier to say that "excess" rotational velocity is a function of residual gravity and that where you have little residual gravity you have no excess rotational velocity. It is also entirely plausible to argue that "null points" are backwaters and that this explains why you get relatively few major galaxies appearing at such points but do get minor multi-stellar structures.

  • by Anonymous Coward on Monday December 05, 2011 @08:30PM (#38274558)

    Odd how the fanatical, radical athiests get away with trolling so easily, and sometimes get modded up. Athiesm takes as much of a leap of faith as belief in a diety or dieties.

    That's "deity". And atheism requires no leap of faith. Just the opposite, it's a lack of faith in things which require faith.

    More if you've actually experienced a diety.

    Nobody has. Yes, I know you'll probably claim you have, but I don't believe you. Religious nutters always love to talk about how their relationship with god has transformed them, but on closer examination the supposed relationship is always rather distant, so much so that the most plausible explanation is that the nutter is inventing it in his or her own mind. We know enough about human psychology to understand how the mind can delude itself into creating a relationship with a being that doesn't really exist.

    It's sad how so many athiests think religion is anti-science, and how they somehow think that you can have science or religion but not both, when over half of scientists are in fact religious.

    It's sad when anyone otherwise dedicated to science decides to compartmentalize their mind so they don't insist on the same standard of proof for the existence of god as they do everything else. But not unexpected given that scientists are members of society, and society is soaked in god delusions.

    Nevertheless, scientists are significantly more atheistic than the general population. To be successful at science, you must at least partially integrate the logical, empirical view of the universe which is the backbone of science. Anyone with that philosophical orientation who also allows God out of that don't-think-about-this-logically mental compartment quickly notices that science has eliminated the need for a god to explain anything, and how laughable the evidence for every human religion is. This is a fast track to atheism, or religious-in-name-only (identifies as religious, but doesn't really believe, attends services irregularly for social value and lingering love of the ritual).

    You don't have to be a bona fide trained scientist to notice those weaknesses either. I deconverted from Catholicism because the religious and scientific instruction in their own schooling got me to notice what a shaky foundation the religion had. (I include the religious instruction because so much of it was concerned with how much better and more logical Catholicism was than other religions, yet it was easy for me to see through the apologetics and realize that the criticisms actually cut both ways.) 20+ years later, with a much more sophisticated understanding of all the issues I first explored at age 13, I still have not found a reason to believe in any god.

    I wish everyone would stop the damned trolling. It annoys me and detracts from slashdot. This thread is no place for a religious discussion. And if they don't believe in a diety why do they even mention one?

    Oh noes mcgrew can't handle that other people disagree with him about the existence of his magical sky daddy. He wants unearned hands-off don't-go-there respect, the respect religion has gotten for millenia just because It's Religion! And therefore Untouchable!

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