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Dark matter doesn't (or what's the matter with dark matter? or pick your lame pun)

  1. Jun 29, 2004 #1
    i'm interested in any alternative theories re: dark matter...is it possible that we simply have misunderstood gravity at these distances? it seems strange to me that we look for symmetry in the physical laws and so we see something we can't explain using the law of gravitation and our observations and we then assume that our observations are off...

    i was reading about some vague theory of an extra spatial dimension, curved and about the length of half a galaxy or so that forced gravitational radiation into a less-than-radial, or actually straight, path, thus at distances proportional to the length of the hidden dimension gravity would not diminish as the square of the distance...does anyone know about this theory?

    are there any other ways of explaining dark matter without invoking 'dark matter'...
  2. jcsd
  3. Jul 1, 2004 #2
    Dark matter could be compounded gravity affects, that is not just the affects from one atom to another but also the additive affect form one atom to the other 2 atom cluster, smaller affect but still additive, like a lower density unit of hot air rises perhaps due to this instead of gravity only affecting the individual atoms alone in the hot air, or I don't understand this.

    Dark matter doesn't matter because you can't see it anyway-Ultra lame
    Last edited by a moderator: Jul 1, 2004
  4. Jul 1, 2004 #3


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    Yes, look up MOND, however it seems unlikely that this is the case.

    Should we expect most of the matter in the universe to be of the type that can directly observed?
  5. Jul 1, 2004 #4
    thank you guys, modified newtonian dynamics link here

    an interesting question alright...i don't know if it makes sense to to expect one thing or the other - why shouldn't most of all forms of matter be able to radiate in some form? it's a philosophical point until we have a theory that explains the observations...i don't think 'dark matter' is a very precise theory...maybe a powerful accelerator will be able to make some in a few decades, but that still won't justify the theory until we can postdict the amount that is necessary to explain graviational anomolies...
  6. Jul 4, 2004 #5
    One published source of errors in the predictuion of dark matter is in measuring the velocity of stars or galaxies on the outer edge of the galaxy or super galxy. Here they say the velocity is to fast for these entities, therfore there must be more mass that keeps the galaxies to gether. WEll any way some have looked at the problem and discovered the phenomena of 'interlopers'. When measuring a galaxy there is always a chance that you are looking at a star, or galxay either in front of the one you think you are viewing, or on the far side of the galaxy. Therefore one may be measuring 'interlopers' that give the viewer the fantasy that the outer stars are moving too fast in the galaxy, or super galaxy, to which they do not belong.

    You aren't suggesting that real physicists contrive theories to conform to their pesonal beliefs are you? Such heresy. You can get in big trouble talking like tha around here. You'd better watch your step buddy!! :devil:

    No bright strories on the dark pages, of interlopers that matter behind the scene are seen, that's for sure.
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