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Dark Black Hole

  1. Sep 4, 2011 #1
    1) Is density of dark matter in the center of the Sun larger than the surroundings ?

    2) Do dark matter fall into black holes? If so how energy is released outward?

    Last edited: Sep 4, 2011
  2. jcsd
  3. Sep 4, 2011 #2
    1. Although there are possible ways in which DM is able to get rid of energy, thus become bound to some structure (very important for early universe structure formation), I don't think that density of DM in the center of the Sun is larger then the surroundings.

    2. Yes, dark matter does fall into the black holes. It does not experience friction, which helps normal matter to spiral into the black hole by radiating energy. So, in a sense, dark matter falls less then ordinary matter into the black holes, as they represent smaller targets for DM. Energy is not released outward, because it is a black hole.
    Last edited: Sep 4, 2011
  4. Sep 4, 2011 #3
    Hi, Calimero.

    Thank you for your reply. Considering it further I have the following idea.

    DM particles surrounding the galaxy are in oscillating motion around the center of gravity with no collision or friction with other particles and ordinary matter. Density of DM particle are roughly proportional to exp(-(R/L)^2) where R is distance from the center of gravity and L is appropriate parameter of dimension of length. During this motion some DM particles disappear trapped by BHs.

    Last edited: Sep 5, 2011
  5. Sep 7, 2011 #4
    I'm sorry, maybe I am missing information, but where is the basis for your claim that dark matter does not experience friction?
  6. Sep 7, 2011 #5


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    Dark matter is collisionless, hence no friction. So, yes, you are missing information.
  7. Sep 8, 2011 #6
    Going a little off topic here, so stop me if this is too large a tangent, but how do we know Dark Matter is collisionless?
  8. Sep 9, 2011 #7
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