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Undetermined future, certain past?

  1. Feb 24, 2007 #1
    If the future is undetermined (unobserved), would the past be certain (observable)?
  2. jcsd
  3. Feb 24, 2007 #2
    isnt it that the future is undetermined (unobserved), and the past is certain (observed).

    Also, The past is observable in some cases as watching stars in the sky, as the images we get are often very, very old.
  4. Feb 24, 2007 #3
    I am going to say no. The past is just as uncertain as the future is. Unless you have some information about the past, you really do not have a clear knowledge of events. You can extrapolate and infer on events, but you cant fully know them (unless you have some form of a record, and even this would be imprecise).

    As you have it written, what instrument would you use to 'observe' the past?
    Last edited: Feb 24, 2007
  5. Feb 25, 2007 #4
    We have the ability and inevitability to observe ("observable") whatever past quantum-photonic events impinge on us, even though the Minkowski light cone seems to imply (for flat space at least) that we are causally connected to all lightlike events, past and future. Perhaps the crux of relativity's dispute with quantum mechanics is the global curvature of spacetime (the inability to record all past) and the process of recording interactions (such as wavefunction collapse temporal asymmetry) at present.

    Observe the past? With a telescope or other radiation detector. Maybe, some day, interdimensionally with branes.
  6. Feb 25, 2007 #5
    Well, not quite. A telescope will only show you as far as the light takes to reach you. I'd hardly consider that 'looking into the past' in a meaningful sense.

    For example, how are you going to 'detect' something in the past that is further back than the time it takes for the light to reach your eyes? Unless you can look back at any arbitrary point in the past, you dont know everything about the past, do you?

    If we could know the past, the question of how the universe was created would be answered.
    Last edited: Feb 25, 2007
  7. Feb 25, 2007 #6
    Hmm, here is something I just thought up. I don’t know if it’s worth a hoot, but Ill just chuck it out there.

    Right now, I know the laws of physics apply. There is going to be uncertainty in my measurements and I cannot get rid of these uncertainties.

    In the future, I know these exact same laws "MUST" apply. If not, it means that at some point I should suddenly see the laws of physics change (because eventually I will be at that point in the future where uncertainty is now gone).

    This means there should be uncertainty in predicting the future.

    Similarly, I know that everything that happened in the past was based on what was at the time my present.

    So to infer that looking into the past will eliminate uncertainty is to infer that uncertainty did not exist at some point that was my present.

    But we know this has never been true at any point in time we considered "present". So it seems to defy physics to know even the past with certainty.

    Of course, none of what I said would apply if, somehow, looking into the past 'bypasses' unceratainty altogether. Though, thats a mighty big assumption.
    Last edited: Feb 25, 2007
  8. Feb 25, 2007 #7


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    Sorry, but this thread isn't even touching upon any of these requirements for a philosophy topic.
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