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If the big crunch theory is correct, Then wouldn't history repeat itself?

  1. Aug 4, 2008 #1
    Assuming the Universe collapses into a giant black hole and the energy as a result leads to a 2nd Big Bang, Wouldn't "history" repeat itself?

    Assuming condition were the same which I don't see why they wouldn't be and energy content will be identical.

    But the only problem is this would assume all scientific law are the same, which is unknown.

    Wouldn't this fulfill Laplace's demon since the the energy is in a single place?

    this is very speculative,it is just a thought...I am a physics noob,,,,
  2. jcsd
  3. Aug 4, 2008 #2
    My guess is that the uncertainty principle suggests history will not repeat itself. Einstein famously said "God does not play dice with the universe". Modern quantum theory suggests Einstein was wrong on that point. However, just because for example we are unable to predict which atom in a radioactive sample will decay next, that does not in itself prove that if the universe replayed itself the exact same atoms would decay in the same sequence. That is the deterministic view of the universe and it implies no free will. In other words, whatever we decisions we make, however carefully thought out or random they seem, we would have done it anyway. One of the explanations for quantum phenomena is that every event in the universe from the Big Bang to the infinite future is predetermined and it is very difficult to prove that is not the case. Does anyone know of a proof?
  4. Aug 4, 2008 #3
    But hasn't everything happened for a set reason involving energy?
    For some reason post-big bang, matter formed in certain places. Energy also moved in certain ways for reasons...right?

    Isn't the universe like one giant chain reaction?
  5. Aug 4, 2008 #4


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    Staff: Mentor

    No. Read what was said above about the Heisenberg Uncertainty Principle. It means that the universe is not deterministic.
  6. Aug 6, 2008 #5
    Deterministic or not, it does not really matter.

    If there is finite matter and finite space, there are only so many ways to combine them. If the cycle is infinite, then yes, history would repeat itself. Not necessarily right away, but eventually. In fact, every possible combination would happen an infinite number of times.

  7. Aug 6, 2008 #6
    The uncertainty principle does not exclude the universe from being deterministic, it just states that there are limitations in measuring.
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