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Inital energy of the universe

  1. Apr 13, 2013 #1
    I am wondering what people here think the initial energy of the universe was.

    The Planck energy? Implies a finite amount of energy
    A Singularity? This implies an infinite amount of energy.
  2. jcsd
  3. Apr 13, 2013 #2


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    Zero? Implies that Lawrence Krauss is right.(:P)
  4. Apr 13, 2013 #3
    Thanks Bandersnatch. I'd thought of listing that too, but it was my impression that at the moment the expansion started that at least a little something was there. My post was purposely vague though and left that idea fully available.
    The initial singularity is often described as being of infinite energy and matter: http://en.wikipedia.org/wiki/Initial_singularity
    Infinite is infinite.... it would not be a universe from nothing, if there was a singularity of infinite energy at the moment expansion started; all the energy is already there. I have heard lecturers state the universe started with a small amount of energy, quite contrary to an infinite amount. With two extremes, I wanted to hear input from forum members.
    I guess I should define the starting condition I am thinking of, and that is the start of expansion.
  5. Apr 14, 2013 #4


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    Actually, there isn't an unambiguous answer to this question: global energy is not a well-defined quantity in General Relativity. Either way, the answer is probably somewhere between small and zero, depending upon how you define the global energy.
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