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Graviton Link to Dark Matter?

  1. Mar 25, 2010 #1
    Hey guys, I was just pondering the idea of dark matter and a thought crossed my mind.

    I may be entirely off, but a few connections can be made between gravitons and dark matter. Neither can be detected directly with any classical methods (EM, pressure, etc..), and dark matter has no apparent "mass", for its mass is attributed to the excess of gravitational force in galaxies. Perhaps free-floating gravitons that are concentrated around galaxies and are undetectable a possible suspect for dark matter? I know that, theoretically, gravitons are supposed to be contained in hadrons, but perhaps a large amount of them were not bonded with matter during the big bang?

    Is this even possible?
  2. jcsd
  3. Mar 30, 2010 #2


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    I think you've misread something along the way. Gravitons are not expected to be concentrated inside hadrons.

    Dark matter, if understood as a WIMP, does have a mass, and can be detected 'classically' by looking for collisions between dark matter particles and those in liquid detectors. WIMPs of the right mass and interaction strength do well to explain the phenomenology of galaxy rotation curves, CMB oscillations, and structure formation.

    Gravitons are massless, and are currently only understood in GR perturbatively (as gravitational waves). It's not clear how a relativistic species like gravitons might clump in the way cold dark matter does. In other words, whatever is comprising the cold dark matter of the universe, it is gravitationally unstable (it forms clumps). Gravitons move at the speed of light and would simply flow out of overdensities.
  4. Mar 30, 2010 #3
    Thank you for clearing that up mate. It seems I have misread something.
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