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How to see the future?

  1. May 26, 2007 #1
    Hello guys I'm just wondering about an optical concept in a fictional movie I've watched. In the movie, there was a machine invented to be able to see someone’s future. The optical concept about this machine is the power of lenses which enable the user to view the light that came from here, on earth, except that this light had already revolved around the universe. It was said in the movie that when this light is viewed, you’ll be ale to see the future. My problem is this: in my study in optics, it’s really possible to see someone’s or something’s past, like the stars we’re seeing every night, but how come you’ll be able to see your future? I know that this movie is fictional but I’m just wondering if there’s really an explanation in physics about this. :uhh:

    Thanks for reading and I’ll appreciate any of your humble replies.
    Anyways, the movie was Paycheck, one of my favorite movies about physics.:cool:

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  2. jcsd
  3. May 26, 2007 #2


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    No, even if light had time to circumnavigate the universe, you would see the past, not the future. If the moviemakers had any real science concept in mind, maybe they were imagining a rotating Godel universe, in which it would be possible for any object or light beam to travel back in time if it circumnavigated the universe...see this page for more info:


    However, the observational evidence does not support the idea that we live in this type of universe...see the Is our Universe Rotating? section from the above page.

    I guess it's also vaguely possible they could have been thinking of a "Gold Universe" where the thermodynamic arrow of time reverses after the universe reaches its maximum size, so that entropy increases after the Big Bang but then after the midpoint it decreases until the Big Crunch...in such a universe it is conceivable that stars in the future contracting phase of the universe could be observed today because reverse-entropy electromagnetic waves would jump off telescopes in order to converge on them in the future. This wouldn't let you directly observe Earth in the future, but it would allow you to send messages back in time if the light from the back of the telescope would actually stop heading towards the future star slightly before you close the telescope's shutter...see p. 19 of this paper for a discussion of this possibility. But reversing-entropy models are considered very unlikely, besides which our universe does not seem on course to collapse, but instead to expand forever. Anyway, I really doubt anyone involved with the movie was thinking of a possibility this obscure.
    Last edited: May 26, 2007
  4. May 26, 2007 #3
    thx so much JesseM. So they are just imagining a different universe and there's really no physical concept about it. Thx!
    Last edited: May 27, 2007
  5. May 27, 2007 #4
    It is possible to see the past, anything else is impossible though. time goes in one direction. you can slow down but you cannot get something from now into the past, but you can get something out of the past into the present (only if certain arrangemtns are made at the time of moving it in the past, that means you cant reach into a portal and pull someone out of the way of a car crash that hasnt happened yet.)
  6. May 27, 2007 #5
    this is the quantum physics forum so you obviously should consider what quantum cosmology says about the evolution of the cosmic wavefunction- the unitary description says that you cannot really see into the 'future' becasue all possible futures happen and it is not possible even in principle to figure out which future history will be observed- although thanks to causality the probabilistic distribution of futures should be highly confined to a few specific path-types- but only on the gross features of cosmic evolution- not the details of human life- the 'past' is the same- but the nature of causality and entropy restrict the past to much more certain histories- so the past appears more determined to observers because we have much more information about the possible events that could lead to the current world-state
  7. Jun 3, 2007 #6
    An extremely interesting thread I think. Quite well explained too! I've read the papers and although I am no physicist looking into the future would be quite hard. Because I'm pretty sure the future hasn't been done yet and there is no way to 100% predict it, we are forced to map out all the probabilities of future states which in itself already means that looking into one certain future is already impossible because in theory we don't know which path the future is taking.
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