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What happened would happen

  1. Oct 14, 2013 #1
    Hey guys,

    Is there a theory in Quantum or general physics which states that at t0 we don't know whats gona happen at t1. But after it happens that was going to happen no matter what .

    Like if an atom is at X at t0. We don't know whether it would be at Y or Z at t1. It goes to Y at t1. Now no matter what we could have done or what the initial conditions were at t0 the atom would have been at Y at t1? Even if it wasn't at X at t0.
  2. jcsd
  3. Oct 14, 2013 #2
    Welcome to the physics forums Ahmed.

    Due to quantum/vacuum fluctuations, there will be some uncertainty (Heisenberg's Uncertainty Principle) in position/momentum/time/energy etc.

    It happens for very small time periods....all the time

    Quantum fluctuations may have been very important in the formation/determination of the structure of the universe.

    I don't know much about it however you can read about it on the internet.
    Last edited: Oct 14, 2013
  4. Oct 14, 2013 #3

    Simon Bridge

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    Welcome to PF;
    There is no destiny after the fact.
    Start with different initial conditions and things may well come out differently.
  5. Oct 15, 2013 #4
    It's an interesting question. It appears to me that once something "has happened" (t1), it is always possible to create a deterministic story about it by asserting conditions at t0 that were unavailable to observers at t0 because of Heisenberg Uncertainty. Of course, you're still going to have to deal with statistics (Bell Inequalities) that make thing look very preplanned.

    This is only my observation. Perhaps someone else in this forum can describe an exception.
  6. Oct 15, 2013 #5

    Simon Bridge

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    Things always look predestined after the fact. It's the source of a lot of creationist literature.
    Similarly, you can always work out a narrative where something different had been done instead.
    (The source of a lot of SF and speculations about the nature of causality and history.)

    But you can never know the outcome of having done something different for that exact situation - you can only know what happened that time.
  7. Oct 16, 2013 #6
    i think the most interesting thing here is that well we can't predict with certainty the outcomes in the scale of elementary particles but we can in the classical world , as to what Simon said last , I i;m not saying that determinism is a perfect or real rule of both the classical and the quantum world but you have to understand at the same time ,and I think every thinker and decent soul does that ,that everything we have ever seen or dealt with kinda remarkably has the functions and properties we need.
    In other words it sticks together remarkably well , maybe even too good to be a random chance , but as to the OP and the original thought for atoms we really can't predict with certainty their positions at a moment ahead of us , it' s either over our heads or just impossible fundamentally but which one ill let you decide because science hasn't arrived at an answer for this case and strong opinions on both sides are just that opinions not fundamental proof.
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