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Question about gravity and time

  1. Nov 20, 2008 #1
    Let's suppose we have infinite space and infinite amount of time.
    Space is initially filled with randomly distributed matter and antimatter. Average density of matter might be similar to what we observe in galactic arms.

    My question is: What will happen? How this setup will evolve in time? I'm seeking answer only based on well established theories. No dark matter, dark energy, no unknown particles, and let's assume space does not inflate in time.
  2. jcsd
  3. Nov 20, 2008 #2


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    Even if this could be done, you have given an incomplete initial condition.

    Notice that when you try to write down the Hamiltonian of a system, be it classical or quantum mechanically, you need not only to know the "positions", but also the "momentum", i.e. how are they moving at the initial condition. So just simply stating that these are "randomly distributed" is insufficient.

    And if someone has the ability to actually solve completely the most general system with more than 3 bodies, I'll name my blueberry muffin recipe after him/her.

  4. Nov 20, 2008 #3
    You are free to assume anything that you are missing. Let's assume that initial momentum is zero.

    Let's make another assumption. Matter and antimatter are initially in equal proportions.

    I don't want exact results. Only kind of rough idea how it will evolve. You can't solve general 3 body system but surely can tell how galaxy will generally look in a million year or two.
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