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Speculative Time Jump Question

  1. Jun 22, 2011 #1
    I'm sure this has been asked 1000 times before, but here's my shot:

    If I had a time machine and intantaneously 'jumped' 1 hour in the future, would I lose all my kinematic vector (velocity, acceleration) during my time jump?

    I read on another thread on PF that the Earth is moving roughly 390 km/s considering motion around sun, sun's motion around galaxy, galaxy rotation through whatever. So it seems that after my time jump the Earth will have moved 1,404,000 km and I will be hopelessly adrift in space.

    It would seem that I should build my time machine with a very elaborate teleportation feature, or else do it in a space ship which means I would be spending a lot of time catching up to the Earth. 390 km/s is really, really fast!

    I'm curious about what the theoretical folks think, and yes, I have lost sleep over this!
  2. jcsd
  3. Jun 22, 2011 #2

    Vanadium 50

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    A time machine hasn't been invented, so speculating as to its properties seems kind of pointless.
  4. Jun 22, 2011 #3
    It's hard to say what would happen because you haven't described how the time machine does it.

    Seems to me your machine needs to specify your 4-coordinates for where you're going as well as your rest frame upon your arrival.

    Try it on a little lizard before you step through yourself.
  5. Jun 22, 2011 #4


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    :rofl: You owe me a new keyboard! :tongue2:
  6. Jun 22, 2011 #5


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    Yes, the trouble is that how it is operated will depend entirely on the physics by which it hypothetically works. The method by which the device reaches into the future and establishes a point the will dictate the freedoms by which that point can be placed.

    You must first invent a plausible way time travel can occur at all, then invent a plausible way of engineering that to come about. By then, you will know what happens to its target location - there will be no choice.

    By a similar example, if you were to build a wormhole, it would be you who would place the target end of it. You could only go to where you were able to place the target.

    With some time machine, you would probably need a receiver at each end with a bridge between them. So your end location would be whereever you put the receiver.
  7. Jun 22, 2011 #6
    I truly appreciate your responses.

    Without the story line (time machine, etc) my question really boils down to this: How would the position and velocity vectors be impacted by an instantaneous change in time?

    I know from calculus that the derivatives for velocity and acceleration depend on continuous time, so this is really the speculative part of the question. If a particle is moving smoothly and then the independent variable is suddenly discontinuous what would happen to the position and velocity? Mathmatically I would assume they would simply be 'not defined' but to me this is a cop out, because in physics I don't think things simply disappear.

    I love the lizard suggestion, but I'd better put a little beacon on him so I can find where he went.

  8. Jun 22, 2011 #7


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    Thread locked pending Moderation.

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