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CERN Physicist Says Dark Matter May Be an Illusion 379

Posted by timothy
from the lunch-dark-matter-doubly-so dept.
anonymousNR writes "A CERN physicist has a new theory explaining the rotational curves of galaxies. 'The key message of my paper is that dark matter may not exist and that phenomena attributed to dark matter may be explained by the gravitational polarization of the quantum vacuum,' Hajdukovic told PhysOrg.com. 'The future experiments and observations will reveal if my results are only (surprising) numerical coincidences or an embryo of a new scientific revolution.' Given the many theories around explaining various observations in recent times, there seems to be a breakthrough on its way in our understanding of the cosmos."
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CERN Physicist Says Dark Matter May Be an Illusion

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  • no dark matter... (Score:5, Insightful)

    by ak_hepcat (468765) <leif@d[ ]li.net ['ena' in gap]> on Saturday August 13, 2011 @08:30PM (#37081960) Homepage Journal

    I hope so. Dark matter is the ugliest kludge to the standard model ever.

    It's worse than the Plus upgrade for Windows 98.

    • Re: (Score:2, Insightful)

      by Antisyzygy (1495469)
      Agreed. I have always had a hard time stomaching the theory that dark matter and dark energy exist. It seems far too much like aether, i.e. something made up to fill a gap in knowledge without much evidence backing it up. "Look, my equations don't work out in every situation. EUREKA! If I just make some shit up like say, invisible matter that doesn't interact with other matter except through gravity, I can make my equations work!". I think its probably that the equations are based on more special cases. Thi
      • by Theovon (109752)

        On the other hand, it doesn't seem like TOO much of a stretch to imagine that there may be massive particles that interact only through gravity and the weak nuclear force.

        • I will admit its not totally unfeasible. I have to if I am to be intellectually honest. However, to me it seems like a taller order to prove there are these particles than to just assume the model doesn't fit every situation since its not complete and does not adjust itself to every situation. Their could be an infinite amount of other explanations for the phenomena rather than just inventing some particle. As a matter of fact, Godel proved that no finite set of axioms can capture all of mathematical truth.
      • Re:no dark matter... (Score:4, Interesting)

        by elistan (578864) on Saturday August 13, 2011 @10:17PM (#37082438)
        I'm no cosmologist, but my understand is that there IS direct evidence of dark matter [universetoday.com] - in the way galaxies collide. Normal matter collides because it interacts through EM and hence slows down, while dark matter doesn't and doesn't. This can be seen by comparing X-ray imaging to map the normal matter and gravitational lensing to map the dark matter.
      • by niklask (1073774) on Saturday August 13, 2011 @10:47PM (#37082556)

        Do you have a hard time stomaching neutrinos too? When they were first proposed they could not be detected. Still they solved the very real problem of explaining the beta-decay spectrum.

      • by roystgnr (4015)

        It seems far too much like aether, i.e. something made up to fill a gap in knowledge without much evidence backing it up.

        This is true of both aether and dark energy... but at one point it was also true of Neptune and neutrinos.

        It's also not quite as true as it used to be of dark matter [physicsworld.com].

      • Dark matter has the same feel to it, but I am not a physicist. And some types of dark matter are observed aka neutrinos. If free neutrons didn't have such a short decay time, I'd consider that option as well. Without electrons the photon interaction with a neutron seems considerably hindered but again I'm not a physicist.
        • by Roger W Moore (538166) on Sunday August 14, 2011 @01:49AM (#37083138) Journal

          And some types of dark matter are observed aka neutrinos.

          Neutrinos are too light to be Dark Matter. Their low mass means that they are produced moving at almost the speed of light so, if they were the Dark Matter, the "wrinkles" we see in the Cosmic Microwave Background would be far more blurred out than they are.

          If free neutrons didn't have such a short decay time, I'd consider that option as well.

          Sorry but neutrons interact via the strong nuclear force and so cannot be dark matter otherwise we would see it interacting with atomic nuclei.

          Without electrons the photon interaction with a neutron seems considerably hindered

          Electrons have nothing to do with photon interactions with neutrons. Neutrons are made of quarks so photons of sufficient energy can directly interact. Electrons can interact with neutrons either via EM (photon) or weak nuclear interactions.

      • by kestasjk (933987) *

        "Look, my equations don't work out in every situation. EUREKA! If I just make some shit up like say, invisible matter that doesn't interact with other matter except through gravity, I can make my equations work!"

        It's a little more complicated than that..

        It's hard for a theory to get an overwhelming majority of scientific opinion without it being pretty solid, and it's much easier to say you think something is wrong than to substitute it for something better.
        ("The models imply matter we can't observe directly, but that can't be! EUREKA! I'll just change the model so that it behaves as if the invisible matter was there even though it actually isn't! How non-kludgy and elegant!")

      • Re:no dark matter... (Score:4, Informative)

        by UnknowingFool (672806) on Sunday August 14, 2011 @01:06AM (#37083014)

        I have always had a hard time stomaching the theory that dark matter and dark energy exist.

        It was never a theory. Based on a number of different observations, physicists could not account for matter and energy that appear to be missing from our observable universe. It was only called dark matter and energy because there was no other way to describe. Based on other determinations, this energy and matter would have weird properties if it existed. Scientists have never actually said it existence but only it might exist. If they could account for this gap of observations due to empirical error, they would embrace it but different aspects of observations suggest that the gap is not easily explained. So right now the focus is on explaining the gap.

        Think of the difference between Newtonian and Relativistic models.

        I think you mean the difference between quantum theory and relativity. Relativity encompasses Newton's models for gravity.

      • by rknop (240417) on Sunday August 14, 2011 @03:41AM (#37083498) Homepage

        Dark Matter is not like the luminiferous aether.

        The luminiferous aether is a substance that was invented to explain something that seemed missing from our theories (specifically, what it is that the speed of electromagnetic waves given by Maxwell's Equations is relative to). It made predictions, those predictions were tested, and so the idea was tossed out.

        Dark Matter is a substance that was explained something that seemed missing from galaxies and clusters of galaxies (specifically, there wasn't enough mass there to explain why they held together given how fast things were moving). The idea of Dark Matter made predictions, those predictions were tested, and they *confirmed* Dark Matter.

        There's nothing magic about Dark Matter. And the lines of evidence are more than just some equations that don't balance out.

        More here: http://365daysofastronomy.org/2010/06/26/june-26th-dark-matter-not-like-the-luminiferous-ether/ [365daysofastronomy.org]

      • by Kjella (173770) on Sunday August 14, 2011 @04:02AM (#37083576) Homepage

        Agreed. I have always had a hard time stomaching the theory that dark matter and dark energy exist. It seems far too much like aether, i.e. something made up to fill a gap in knowledge without much evidence backing it up.

        The problem is that the universe is pretty good at ignoring people's bowel movements, a lot of things are completely unintuitive. If I look at a wall it looks damn solid to me, my gut feeling would be that radio and wireless can't possibly work. And if you told me there are particles that'll pass through thousands of miles of earth and stone and lava without even caring that it's there, I'd say you were ready for a room with padded walls if only it wasn't true. In short, past experience has shown us that this is an area where the universe has a habit of not acting the way people expect.

        That said, we do know our understanding of gravity is incomplete at the quantum level, we probably will get a better understanding of it as we go along. But the unexplained gravitational effect seems variable, lumped together just like real matter and not always directly in proportion to it. I could accept that we might have had to adjust gravity by some sort of factor but it seems a bit too erratic to be just a formula adjustment. I at least am pretty confident that we've not found all the particles yet and that this will be at least part of the explanation.

    • by DesScorp (410532) <DesScorpNO@SPAMGmail.com> on Saturday August 13, 2011 @09:15PM (#37082172) Homepage Journal

      I hope so. Dark matter is the ugliest kludge to the standard model ever.

      It's worse than the Plus upgrade for Windows 98.

      I've long thought that the concept of dark matter was a manifestation of the inability of some scientists to admit "Hell, I don't know".

      • by tragedy (27079)

        Well, actually, in a way, Dark matter is "Hell, I don't know". It's just that it's a bunch of "Hell, I don't know" that fills certain holes in a theory. I'd list all the things that we now understand (better than we did, at least) that were once just "Hell, I don't know" fitting into a hole in a theory, except that I want to finish this post some time this year.

      • by IICV (652597) on Saturday August 13, 2011 @11:39PM (#37082764)

        I've long thought that the concept of dark matter was a manifestation of the inability of some scientists to admit "Hell, I don't know".

        ..what? Dark matter is, by definition, little bits of "hell, I don't know". Fuck, we don't even know if it's bits or bobs or particles or globs! We have no idea what it is at all!

        I mean, why do you think we call it "dark matter"? That is literally all we know about it - we know it has weak electromagnetic interactions (i.e, it's dark), but strong gravitational interactions (i.e, it's matter).

        The thing you really seem to object to is that scientists will say "Hell, I don't know - but I'll put a name on it, and start narrowing down what it can and cannot be".

        I mean, what do you expect? That we'll admit "hell, I don't know" and just stop? And just give up right there? Hell no - saying "I don't know" is the first step of doing science, not the last step!

    • Re:no dark matter... (Score:4, Interesting)

      by IICV (652597) on Saturday August 13, 2011 @10:04PM (#37082388)

      I'd love to see how his model explains something like (e.g) the Bullet Cluster [wikipedia.org], because quite frankly I don't think it does - the article states that his theory explains the speeding up of galactic rotation (the reason why we first hypothesized dark matter), but the article goes on to state that his hypothesis doesn't actually cover a ton of other stuff like the CMB.

      Furthermore, this theory is based on the hypothesis that matter and antimatter are gravitationally repulsive, which (imo) is absolute BS. It's true, we haven't generated enough antimatter yet to know for a fact that it acts the same way as regular matter in a gravitational field generated by regular matter, but we have absolutely no reason to think that it would be gravitationally repulsive. If that turns out to be true, there will need to be a shit-ton of rejiggering of models and basically everything we think we know about physics will have to be moved around.

      Basically, he's said "If pigs can levitate, then I can account for the discrepancy in galactic rotation curves without dark matter" - except if pigs can levitate, we'll need to rethink everything anyway.

  • by istartedi (132515) on Saturday August 13, 2011 @08:31PM (#37081976) Journal

    Yay for phlogiston [wikipedia.org] and aether [wikipedia.org]. Dark matter might end up on the list of ideas that physcists turned to in order to explain things that had other explanations. La plus ca change...

    • by ShakaUVM (157947)

      >>Yay for phlogiston and aether. Dark matter might end up on the list of ideas that physcists turned to in order to explain things that had other explanations. La plus ca change...

      And yet we're back to something like aether with relativity and string theory. Relativity says that empty space has a structure, and string theory says empty space is made up of a lattice of vibrating strings that propagates everything in the universe.

      • Not exactly. At least we can predict certain behaviors using Relativity that enable satellites to work properly as well as a whole slew of other physical behaviors that enable our modern technology to work. If we didn't adjust GPS satellites using relativity they would not work at all. I would wager similar usefulness did not come out of the theory of aether but I am willing to admit I am wrong if you can present evidence to the contrary.
    • Nowadays we like to call the Aether the "Higgs Particle".

      And it's "intents and purposes", not "intensive purposes".
    • by Interoperable (1651953) on Saturday August 13, 2011 @08:49PM (#37082074)

      Hopefully. Dark matter is a very inelegant solution to observations that don't agree with theory. Even so, working out what properties it must have, should it exist, is a useful exercise because it clarifies the problem more thoroughly.

      There seems to be a common misconception that incorrect theories were stupid ideas from the get-go. That's really not the case, until new evidence or new ideas come up the incorrect theories are every bit as valid as the ones that may turn out to be correct and the differences between the various competing theories may point the way to interesting new experiments.

      This new theory is probably wrong, but it's founded on an assumption that, while not currently accepted as true, is experimentally verifiable. That's the assumption that anti-matter and matter have gravitation fields of opposite sign. An experiment to determined the truth of that would be very interesting.

      • by Baloroth (2370816) on Saturday August 13, 2011 @10:32PM (#37082498)

        Exactly. It was the development of the theory of the aether that led to many of the experiments surrounding the properties of light that allowed the theory of relativity to be developed. For instance, we knew if aether existed it would create a "wind" that would slow light in some directions as the earth moved. The experiment to test that wind helped found the theory of relativity (although, interestingly enough, Einstein supposedly hadn't heard of the experiment when he postulated the constancy of the speed of light.)

        Aether was by no means a stupid theory, but it required a number of new properties previously unseen in material bodies, and it was theorized solely as a kludge to explain the motion of light through a vacuum. The analogy with dark matter is quite strong. Dark matter, too, has never been observed, and possesses properties of matter previous unseen or indeed thought impossible, and exists solely to bridge a gap between our model of how things should behave, and how things actually behave. This does not bode well for it. However, the experiment to test for its existence is quite likely to lead to something interesting, even if we have no idea what.

    • But tragically, this time it wasn't even remotely Latin-sounding. Oh, how the times have changed for us poor misbegotten students of scientific nomenclature...
    • Dark matter might end up on the list of ideas that physcists turned to in order to explain things that had other explanations.

      What really surprises me is, despite this, so many physicists have jumped on the bandwagon. Average Slashdotters have been more skeptical of they dark matter theory than physicists, from what I've seen.

      "It's invisible, we have no idea what it looks like, we can't detect it, but it must be there because we have no other ideas." Exactly the same mistake as the theories you point out.

      • by Goaway (82658) on Saturday August 13, 2011 @09:21PM (#37082200) Homepage

        What really surprises me is, despite this, so many physicists have jumped on the bandwagon.

        This is because it is the simplest theory which fits available data. There are simpler theories, but they do not fit available data, and thus are of little value.

        Average Slashdotters have been more skeptical of they dark matter theory than physicists, from what I've seen.

        This is because average Slashdotters do not have even the beginnings of a clue about astrophysics, but think they are expert at every subject they ever heard mentioned on the internet.

        • by bertok (226922) on Saturday August 13, 2011 @10:56PM (#37082590)

          This is because it is the simplest theory which fits available data.

          But it doesn't fit the data -- the dark matter theory is constantly being revised. First it's "90%" of the mass of the universe, then it's "70%", then we're back to "98%", then there's dark energy, then the fractions change again, and again, and again.

          That's not a fit! It's not like we started at, say, 80%, then refined the fit to 82.5%, then an additional data helped us narrow it down to 82.515%, and so on. It's just jumping all over the place.

          Secondly, it's not "fitting to the data", it's fitting to the difference between a theory and the data. There's a huge difference. And it's particularly galling that the "theory" used is Newtonian gravity, when it's been known to be wrong for a century! Several papers have been released that show that it's possible to make the need for dark matter vanish by using relativistic mechanics. Not exactly surprising that the "difference" is affected by the theory chosen!

          Every research paper about dark matter reads something like "we use a simplified theory of gravity because of [excuse], and then oh look, we find that our hugely simplified model doesn't agree with observations, so clearly there's an invisible something out there". The excuses vary between: "The other paper did it too", "Relativistic equations are hard, and I'm lazy", "I don't understand relativity so I don't know how it could possibly apply to galaxy sized masses thousands of light years in size", and "my computer is too slow to do this properly".

          This is because average Slashdotters do not have even the beginnings of a clue about astrophysics

          Yeah, well, I studied Physics at a university level, and I think dark matter smacks of hubris, laziness, and weak logic. It sounds an awful lot like chasing the error terms in Epicycles [wikipedia.org] a century too late.

          The latest attempts to explain dark matter are an ever bigger joke, like Modified Newtonian dynamics [wikipedia.org]. Here's a hint... we already have a "modified" theory for motion -- it's called relativistic dynamics!

          Until some physicist demonstrates that dark matter is still required to explain measurements when the theory used is the full general relativistic model with speed of light delay included, I'm just going to automatically assume that dark matter is bullshit.

          This kind of thinking is all too common in Physics. A classic example is the double-slit experiment [wikipedia.org]. Every textbook states a formula for the spacing of the interference fringes that disregards a bunch of things, handwaving them away as "unimportant". A math-geek friend of mine in my physics class was upset by this lack of rigor, walked up to the whiteboard, and demonstrated that the simplifications can result in errors as large as ten percent or more in real-world scenarios!

          Imagine someone basing a new theory of light based on the difference between observed interference fringe spacing and the simplified theory. That would be stupid, wouldn't it? Why is it then acceptable for gravity?

          • by IICV (652597) on Sunday August 14, 2011 @02:35AM (#37083282)

            How can you possibly not know about the Bullet Cluster? [wikipedia.org] That is pretty much blatant evidence that there appears to be something there which is both dark and massive. Wouldn't a theory of dark matter be appropriate when presented with such evidence? (and, by the way, structures like the Bullet Cluster were predicted by the theory of dark matter - people said "well if it doesn't interact electromagnetically, we should be able to see places where normal matter got pushed but dark matter didn't, like when two clusters collide" - so they set out to look for something like that, and lo and behold they found it!)

            And that's not even going in to the other things that dark matter predicts and nothing else does, like the Cosmic Microwave Background.

            Or you could just read Starts with a Bang [scienceblogs.com], Ethan Siegel is a lot better at explaining this stuff than Slashdot is.

          • Re: (Score:3, Informative)

            by maxwell demon (590494)

            But it doesn't fit the data -- the dark matter theory is constantly being revised. First it's "90%" of the mass of the universe, then it's "70%", then we're back to "98%", then there's dark energy, then the fractions change again, and again, and again.

            About the changing numbers, I'd like to see citations.

            Dark energy is a completely different concept than dark matter, completely independent of it, and used to explain completely different phenomena. The only thing dark matter and dark energy have in common is

          • by Anonymous Coward on Sunday August 14, 2011 @03:42AM (#37083500)

            This is because it is the simplest theory which fits available data.

            But it doesn't fit the data

            Well, I am a physicist (doing my PHD, although not in astrophysics), and I can tell you that it certainly looks like the simplest theory that fits the data. I highly recommend Ethan's blog, who explains this very well, particularly http://scienceblogs.com/startswithabang/2011/03/good_ideas_bad_ideas_mond_and.php [scienceblogs.com] and
            http://scienceblogs.com/startswithabang/2009/09/dark_matter_part_i_how_much_ma.php [scienceblogs.com]. Notice, also, that theory predicts that the percentage of darks matter and energy changed during the history of our universe.

            Of course, the theory is not complete, and there should be further experimental confirmation, but it looks pretty good for now.

            This kind of thinking is all too common in Physics. A classic example is the double-slit experiment [wikipedia.org]. Every textbook states a formula for the spacing of the interference fringes that disregards a bunch of things, handwaving them away as "unimportant". A math-geek friend of mine in my physics class was upset by this lack of rigor, walked up to the whiteboard, and demonstrated that the simplifications can result in errors as large as ten percent or more in real-world scenarios!

            Imagine someone basing a new theory of light based on the difference between observed interference fringe spacing and the simplified theory. That would be stupid, wouldn't it? Why is it then acceptable for gravity?

            Well, I work in optics, and I have no clue what you are talking about here... Is it because the usual derivation uses tan(alpha) ~ sin(alpha) ~ alpha? Or because it disregards the polarization of light? I can assure you that both of those approximations are very good "in most cases". But that doesn't mean you can't use the correct formulas, if needed. More likely, your teacher was oversimplifying the problem to get accross the most important concepts without his students being drowned by little details.

            But much, much more importantly, physicists know that arriving to the simplest model that explains all your experimental data is very important, because it lets you understand what's going on, instead of just making blind calculations. I can assure you that this is not an easy skill to learn, specially for math-loving students who are irritated by approximations (I know this from first-hand experience!).

          • by rknop (240417)

            First it's "90%" of the mass of the universe, then it's "70%", then we're back to "98%", then there's dark energy, then the fractions change again, and again, and again.

            This is not a correct characterization of the history of Dark Matter.

            First of all, if you really studied Physics in university, then you ought to know something about uncertainties. If not, then, shame on the people who gave you your degree.

            The history of dark matter includes observations on different scales that include different amounts o

      • by compro01 (777531)

        Dark matter isn't undetectable, it's just difficult to detect because it doesn't interact with normal matter much. There's experiments, such as the cryonic dark matter search, underway attempting to detect it.

      • So what's your idea? Given that the observed behaviour of the universe is inconsistent with what we expect, there are basically two possibilities:

        1) Our understanding of gravity is wrong.
        2) Our understanding of the matter in the universe is wrong.

        Despite lots of effort, nobody has come up with a satisfactory theory of gravity which fixes the problem. And a new theory to fix the problem is not really more satisfactory in itself than a new type of matter - they both would be fudges to fit the data until some

        • by Nutria (679911)

          Despite lots of effort, nobody has come up with a satisfactory theory of gravity which fixes the problem.

          It's actually *ok* to say, "Our knowledge and theories are incomplete. Once we get more data we can fill in the gaps."

      • They've "jumped on the bandwagon" so to speak, because General Relativity explains everything else really fucking well, so we have a choice when we observe the anomalies; rewrite the entire rulebook, except we don't know how to, or postulate some form of matter that isn't *directly* observable (you know, sort of how like electrons aren't directly observable), and try to explain what it is. Maybe the latter is a fool's errand, but to throw out one of the most successful theories in history because the large

    • by grumling (94709)

      If Aether doesn't exist then what's in all that cat5 cable? Admin tears?

    • Well, that's how science works. You take a theory and as long as you have more things in favor of it than contradicting things, it has merit, at least until you have a better theory with fewer (or no) contradiction that explains nature better.

      But looking at the two examples you present, maybe we should be more open minded when approaching science in general. I'm pretty sure both, phlogiston and aether, caused a lot of people to research into the wrong direction because they were considered solid theories. S

      • by HiThere (15173)

        IIRC, phlogiston was one of the theories that lead to the atomic theory. In fact I seem to recall the Priestly (Lavoisier?) first called Oxygen "de-phlogistonated air" or some such. It was wrong, but a vital step along the way to a better theory.

      • This is the first time I've heard General Relativity referred to as a "pet theory".

      • So you're saying the aether bunny isn't real?
  • According to the article, if quantum dipoles are polarized, then tney produce an additional gravity field.

    Does this mean that if this can happen artificially, we can control gravity?

    • by Baloroth (2370816)
      Yes and no. Until we see it happening, we won't know if we can or not.
    • Not exactly. The article states that physicists assume a positive charge for gravity throughout the universe. Hajdukovic, the guy that wrote the paper (I think), suggests that a negative charge exists, just like with electromagnetism. He suggests that matter produces positive gravity, and antimatter produces negative gravity. Here is an excerpt from http://www.physorg.com/news/2011-08-dark-illusion-quantum-vacuum.html [physorg.com] that explains it better than I.:

      If matter and antimatter are gravitationally repulsive, then it would mean that the virtual particle-antiparticle pairs that exist for a limited time in the quantum vacuum are “gravitational dipoles.” That is, each pair forms a system in which the virtual particle has a positive gravitational charge, while the virtual antiparticle has a negative gravitational charge. In this scenario, the quantum vacuum contains many virtual gravitational dipoles, taking the form of a dipolar fluid.

      “We can consider our universe as a union of two mutually interacting entities,” Hajdukovic said. “The first entity is our ‘normal’ matter (hence we do not assume the existence of dark matter and dark energy), immersed in the second entity, the quantum vacuum, considered as a sea of different kinds of virtual dipoles, including gravitational dipoles.”

      He goes on to explain that the virtual gravitational dipoles in the quantum vacuum can be gravitationally polarized by the baryonic matter in nearby massive stars and galaxies. When the virtual dipoles align, they produce an additional gravitational field that can combine with the gravitational field produced by stars and galaxies. As such, the gravitationally polarized quantum vacuum could produce the same “speeding up” effect on the rotational curves of galaxies as either hypothetical dark matter or a modified law of gravity.

      Basically what this means to me, is that the effect is on

  • by c0lo (1497653) on Saturday August 13, 2011 @08:49PM (#37082070)
    The core explanation from TFA

    He gives an example of a dielectric slab being inserted into a parallel plate capacitor, which results in a decrease in the electric field between the plates. The decrease is due to the fact that the electric charges of opposite sign attract each other. But if the electric charges of opposite sign were repulsive instead of attractive, then the electric field would increase. Back to the quantum vacuum scenario, since the gravitational charges of opposite sign are repulsive, the strength of the gravitational field increases.

    If the gravitational charge of opposite signs are repulsive, it would mean that the "vacuum gravitational dipole" will have a tendency to separate into matter and antimatter.
    As the antimatter is repulsed by the normal matter, wouldn't this require the introduction of another force (the "dark force"?) – that should be even stronger than the strong force – to explain how come we are not seeing flows of antimatter originating from the core of the galaxies?

    • by Daniel_Staal (609844) <DStaal@usa.net> on Saturday August 13, 2011 @09:07PM (#37082144)

      Electromagnetism is stronger than gravity. Given that the particles in question also have the opposite charge, and are therefore attracted electromagnetically, it wouldn't make a major difference to them.

    • by Mogster (459037)

      As the antimatter is repulsed by the normal matter, wouldn't this require the introduction of another force (the "dark force"?) – that should be even stronger than the strong force – to explain how come we are not seeing flows of antimatter originating from the core of the galaxies?

      Do not underestimate the dark side of the Force.

    • by Waccoon (1186667)

      All the antimatter in galaxy cores is in the black holes! Duh!

      Wait... I meant, gravistar.

  • TFA (Score:5, Informative)

    by mojo-raisin (223411) on Saturday August 13, 2011 @08:57PM (#37082112)

    Here's a link to the actual PDF (arxiv version) and not the pay version

    http://arxiv.org/ftp/arxiv/papers/1106/1106.0847.pdf [arxiv.org]

  • by TheMiddleRoad (1153113) on Saturday August 13, 2011 @09:04PM (#37082140)

    Time is an illusion. Dark matter doubly so.

  • gonna work here anymore!!! amiright?

    now, hows the war on terror going? how many muslims have we converted to christianity?

  • Just how much physics and cosmology has come to resemble STTNG technobabel ?

    • That's because TNG technobabble gets an undeserved bad rap. Amidst the truly bad stuff like reversing polarity and tachyon beams, there's a lot of things with a real science basis.

    • Nothing a reverse tachyon impulse can't fix. How? Dunno, but there is effectively nothing a reverse tachyon impulse can't fix.

      • by Nimey (114278)

        ...and I say "bounce the graviton particle beam
        off the main deflector dish"
        That's the way we do things, lads
        Just making shit up as we wish
        The Klingons and the Romulans
        pose no threat to us
        'Cause if we find we're in a bind
        We'll just make some shit up.
            -- Voltaire, "The USS Make Shit Up"

  • by 93 Escort Wagon (326346) on Saturday August 13, 2011 @09:33PM (#37082250)

    Then quantum phenomena must really get your panties in a twist.

    I realize this isn't a group of physicists here, but most of the arguments people here are positing against dark matter more or less boil down to "it's unintuitive". Seriously, welcome to modern physics guys.

    This new idea may be the start of something (and I must say this guy certainly doesn't lack in the self-esteem department), or it may fall apart as it fails to get further developed. But until it - or another alternative idea - gain some traction with the scientific community, it's a bit premature to start writing off dark matter. At the moment, it's the best solution we've got.

    • by tylersoze (789256)

      Yeah I know exactly what you mean. I get this all the time from my non-physicists friends, they seem to be the most skeptical not the actual working physicists and astronomers.

      You know, there's a whole class of particles, called supersymmetric particles, that most extensions to the Standard Model practically *beg* to exist, so it's not such a stretch to think that dark matter might be these one of these stable, neutral massive SUSY particles that only interact through gravity and the weak force.

      I should ask

    • Re: (Score:2, Insightful)

      by HiThere (15173)

      Well, there's also a lot of:
      You're assuming that 90% of the universe is invisible on the basis of *what* evidence? I'd like a bit of better evidence, please, before I swallow something like that.

      It's something that *could* be true, but the evidence is pretty thin for the size of the hypothesis. Maybe it's the best we can do, and maybe it isn't. For a while longer I'm going to presume that eventually we'll come up with either a better answer, or more convincing evidence. The current evidence is proof of

      • by Cyberax (705495) on Saturday August 13, 2011 @11:32PM (#37082736)

        "I'd like a bit of better evidence, please, before I swallow something like that."

        1) Rotational curves of galaxies.
        2) Gravitational lensing - it's too strong for the amount of baryonic matter present.
        3) Bullet cluster ( http://en.wikipedia.org/wiki/Bullet_cluster [wikipedia.org] ).
        4) Small galaxies - the smaller the galaxy the more dark-matter-dominated it is.

        The first one can be somewhat explained by MOND. But MOND can't really explain gravitational lensing (duh, it's Modified _Newtonian_ mechanics) and it is totally busted by 3) and 4). Vacuum polarization is MOND-like in this regard and probably can't explain them as well.

        Actually, the relationship between the amount of dark matter and normal matter in small galaxies is quite interesting. Unlike rotational curves and lensing it has an explanation that has nothing to do with gravitational properties of dark matter. Small galaxies have fairly shallow gravitational wells, so normal matter can be blown away by stellar winds and supernovae explosions. And since dark matter does not interact [much] with the normal matter, it tends to stay. Here's a nice overview: http://scienceblogs.com/startswithabang/2011/08/the_smallest_mini-galaxy_in_th.php [scienceblogs.com]

      • by rknop (240417)

        Well, there's also a lot of:
        You're assuming that 90% of the universe is invisible on the basis of *what* evidence? I'd like a bit of better evidence, please, before I swallow something like that.

        There is lots of evidence. Look up "Bullet Cluster" on the net for the closest thing to a single "smoking gun". Or, for a mention of the Bullet Cluster and lots of other evidence (and not even all of it), watch this: http://vimeo.com/4559703 [vimeo.com]

  • Nothing New (Score:2, Insightful)

    by Anonymous Coward

    From TFP: "Let us end by pointing that the rotational curves of galaxies are not the only phenomenon
    which is currently explained by Dark Matter. For instance, CMB data are apparently in favor of
    the presence of dark matter as a key for understanding of density fluctuations and the structure
    formation in the Universe (see review of Einasto, 2010). While our Letter gives indices that the
    gravitational vacuum polarization could be an alternative to dark matter in the explanation of the
    galactic rotational curves,

  • If there is no dark matter, then what is on the dark side of the moon?

  • "Given the many theories around explaining various observations in recent times, there seems to be a breakthrough is on its way in our understanding of the cosmos."

    So, it seems this quantum effect is able to affect the construction of a sentence is, fascinating.

  • Its the perfect setup for a Star Wars joke.
  • I'm not going to actually read the paper because i have a headache already, and i'm not saying that this guy isn't onto something, but if I had an 'automatic scientific paper generator', 'gravitational polarization of the quantum vacuum' is exactly the sort of phrase it would be likely to spit out :)

  • by pz (113803) on Saturday August 13, 2011 @11:12PM (#37082668) Journal

    Disclaimer: I'm a lay person when it comes to things like quantum physics.

    From my understanding of the arguments and analogies given in the article, the explanation is that vacuum does has a digravitational constant (the gravitational equivalent of the dielectric constant) greater than 1 in strong gravitational fields.

    But, by the same quantum fluctuations getting polarized argument, shouldn't vacuum also have a dielectric constant greater than 1 in strong electrical fields?

    Can't we test that last hypothesis pretty easily? Is it already known?

    The crux of the article's hypothesis, that anti-matter has opposite-sign gravity, seems like an attractive idea and one that should also be easily testable once sufficient anti-matter can be manufactured and contained.

I use technology in order to hate it more properly. -- Nam June Paik

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