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Question - in a WMAP

  1. Nov 27, 2009 #1
    In a WMAP
    Matter(4.6) / Dark matter(23.3) / Dark Energy(72.1)

    100= M_ord(4.6) + M_dark(23.3) + DE(72.1)

    The M_ord is Mc^2 ?
    Matter part is only rest mass energy?

    M_ord ? mc^2 + gravitational potential energy
    M_ord ? mc^2
    Last edited: Nov 27, 2009
  2. jcsd
  3. Nov 28, 2009 #2


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    Science Advisor

    It's difficult to know what you're asking here, but yes, he matter part is effectively only rest mass energy: the kinetic energy component of normal matter is, today, such a minuscule fraction of its energy density that it might as well be neglected.

    In the earlier universe, of course, the kinetic energy had to be taken into account.

    Also, in the formulation of GR that is used in these calculations, gravitational potential energy is not used.
  4. Nov 28, 2009 #3
    Thanks Chalnoth!

    I'm sorry, I can't English well.
    So, my question is short!

    Again, I'm sorry.

    But I get the answer in your answer.

    I really appreciate you!

    --- Icarus2
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