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Thread: Attiyah's Dark Matter

  1. #1 Attiyah's Dark Matter 
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    Attiyah's Dark Matter


    Attiyah's dark matter is the matter that has no space-time dimension.


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  3. #2  
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    If it has no space time dimension then can it interact? I'd like to see a discussion about this one.


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  4. #3  
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    I don't really. It is just another one of his/her absurd and inexplicable ideas. It is not even clear that "dark matter" really exists. The definition given here is also an oxymoron.
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    there is NO way something that doesn't interact with space-time is observable or falsifiable, therefore, it is not a good theory, I personally don't think dark matter is a good theory either, so a theory that bases itself off a bad theory is WAAAAAY off!
    "It's no wonder that truth is stranger than fiction. Fiction has to make sense." - Mark Twain
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  6. #5  
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    What was the original purpose of dark matter?
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    It was discovered that galaxies did not posess enough mass to stay together. The unknown matter was called dark matter. Two candidates for dark matter were identified; MAssive Compact Halo ObjectS (MACHOS) and Weakly Interactive Massive ParticleS (WIMPS). The MACHOS consisted mainly of failed stars called Brown Dwarf stars that have between 20 and 80 times the mass of Jupiter. They don’t have enough mass to maintain hydrogen fusion and don’t shine. Supposedly a tremendous cloud of these objects orbit every galaxy. WIMPS on the other hand are massive subatomic particles that do not interact with the electromagnetic force; hence they pass right through other matter.
    A lot of Brown Dwarf stars have been found, but not enough to account for all the missing matter. However, clouds of WIMPS many light years in diameter have been imaged. These clouds bend light of background galaxies with their gravity (this is called microlensing). Thus dark matter is a little bit of both.
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    That sounds completely plausible to me thanks .

    Unfortunately for Attiyah if the Dark Matter had no space time dimension it wouldn't be very effective at having mass as we understand it which kind of voids its purpose does it not?
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  9. #8  
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    Quote Originally Posted by Arch2008
    It was discovered that galaxies did not posess enough mass to stay together.
    Actually, the differential rotation velocities of many galaxies cannot be explained by the visible matter of stars, gas and dust. If simply the Kepler law is adopted, this means that there must be much more mass hidden somewhere than can be seen. This is the reason, why "Dark Matter" was invented.

    Quote Originally Posted by Arch2008
    Two candidates for dark matter were identified; MAssive Compact Halo ObjectS (MACHOS) and Weakly Interactive Massive ParticleS (WIMPS). [...] However, clouds of WIMPS many light years in diameter have been imaged. These clouds bend light of background galaxies with their gravity (this is called microlensing). Thus dark matter is a little bit of both.
    No, these particles are still hypothetical. They have not been observed. There are large particle collider projects running at the moment to find them. It is always only indirect evidence that has been found. They cannot be imaged, because they do not interact via electromagnetics, just gravity. So, they also do not emit any radiation. Very strange!

    There is another concept that can describe the rotation curves at least as good as the "Dark Matter". It requires a slight modification of the law of gravity. The classical (Newtonian) modification is called "Modified Newtonian Dynamics (MOND)". It cannot explain relativistic phenomena, but it was extended to a relativistic version (TeVeS = Tensor Vector Scalar) that can equally explain gravitational lensing as well.
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  10. #9  
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    Dishmaster is correct. When observing distant galaxies, it was found that the rotational speed of stars near the centre was the same as that at the edges, something that ordinarily would be impossible. Something has to be effecting gravity in a BIG way..hence dark matter.

    As far as what it is, this has yet to be discovered, but it certainly does exist.
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  11. #10 Here we go again... 
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    Actually, WMAP evidence discounted MOND completely and NASA has imaged clouds of WIMPS. No one has directly seen a quark, but they are part of our universe, as are WIMPS.
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  12. #11 Re: Here we go again... 
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    Quote Originally Posted by Arch2008
    Actually, WMAP evidence discounted MOND completely and NASA has imaged clouds of WIMPS. No one has directly seen a quark, but they are part of our universe, as are WIMPS.
    Ah, that's interesting. Can you provide a link?
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  13. #12  
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    My pleasure:

    http://www.esi-topics.com/cosmic/int...sLBennett.html

    As to the existence of WIMPS:

    “WMAP data were also only consistent with a substantial amount of nonbaryonic cold dark matter.”

    And the premise that gravity needs to be modified:

    “The fact that the physics was simple enough to calculate, and that the calculations fit the measurements, told us we really do understand a lot about the universe. Our basic picture of the hot big bang, the expanding universe, the accelerating expansion, components of baryons, cold dark matter, dark energy—all of that—seems to be needed. We would get different microwave patterns across the sky if the universe had different ingredients or different physics. I’m struck that the maps are in such close agreement with these prior theoretical predictions—with a relatively simple universe. “

    Also, the WMAP indicates a smooth universe without any areas where gravity shifted gears as MOND predicts.
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  14. #13  
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    Quote Originally Posted by Arch2008
    Thanks. That really reads itself interesting. I must say that I don't understand enough about these measurements and how the quoted models are used. But I did my own research on publications and found at least two from 2004 and 2006 saying that relativistic MOND cannot be entirely excluded. Apparently, from what I've read, TeVeS models fit well enough to attribute the remaining differences to the inaccuracy of measurements and fundamental quantities. These are publications only available to subscribers of these journals. I can try to provide them, if this would be interesting.
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    Well perhaps I’m jumping the gun, but the evidence from WMAP is pretty convincing. I read in Astronomy magazine last year how this closes the door on MOND. Don’t get me wrong, MOND was good science and we should question the answers. However, a time comes when the answers are fairly clear. It’s true that the Nobel committee hasn’t issued any pronouncements yet, but I’m not one to wait for the priests at Stonehenge to tell me when the summer solstice has arrived.

    P.S. Here's that image of a dark matter ring taken by Hubble.
    http://www.astronomy.com/asy/default.aspx?c=a&id=5535
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  16. #15  
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    Quote Originally Posted by Arch2008
    Well perhaps I’m jumping the gun, but the evidence from WMAP is pretty convincing. I read in Astronomy magazine last year how this closes the door on MOND. Don’t get me wrong, MOND was good science and we should question the answers. However, a time comes when the answers are fairly clear. It’s true that the Nobel committee hasn’t issued any pronouncements yet, but I’m not one to wait for the priests at Stonehenge to tell me when the summer solstice has arrived.

    P.S. Here's that image of a dark matter ring taken by Hubble.
    http://www.astronomy.com/asy/default.aspx?c=a&id=5535
    I agree that it doesn't look very promising for MOND and related concepts. But I really would hate Dark Matter to be real, because it seems so artificial to me. This guy in the article said, that this would demonstrate the universe to be very simple. I would disagree with this opnion. To me it is not a simple concept to be in need of a new particle for every inexplicable phenomenon.

    Regarding the image of the Dark Matter, I was suspecting exactly this press release. It has caused a lot of confusion. Whether this was intentional or not remains to be investigated. This is NOT an image of the Dark Matter. It is a result of model calculations and a reconstruction of the distribution of Dark Matter, if it exists. This is also said so in the article, although it is hidden in the relative clauses. Dark Matter does not interact via electromagnism, and hence it cannot emit detectable radiation.
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  17. #16 Re: Attiyah's Dark Matter 
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    Quote Originally Posted by Attiyah Zahdeh
    Attiyah's Dark Matter


    Attiyah's dark matter is the matter that has no space-time dimension.
    for one is there any proff for this magical matter.

    two, dark matter is matter that does not act with the elcrtomagnetic force but has dimmentions so your made up matter is not dark matter.

    three, how could it be matter if it does not have dimention. that is physically and quantumly impossible.


    when you come up with an idea it needs to based on physical proff and logical ideas.
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  18. #17  
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    Dishmaster-Einstein hated his cosmological constant and this dislike probably cost him his third Nobel Prize. Science doesn’t really require our emotional attachment, though. As in personal relationships, you’ll never make friends by being absolutely, brutally honest. However, scientists have to be. Jee and his group did not start out with an agenda to find a ring of dark matter. As with most discoveries, it just happened. Jee didn’t call a press conference the day after he made this discovery. To prevent confusion, he studied it…for a whole year. Of course, you can’t show a picture of something that is invisible. A computer enhanced those areas of the image where gravity from the dark matter lensed the light from the background galaxies, so that the effect of the dark matter was more apparent. Let’s say I took a picture of an empty room and called the image “Air”. I might suspend dust particles in the air so that there would at least be something to look at, even though some people might think that this was a deliberate attempt to be confusing. Whatever you choose to believe, the air is still there and so is the dark matter.
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