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Intuition behind the warp drive

  1. Nov 19, 2013 #1
    I have been pondering about the concept of the warp drive and my intuition can't seem to understand the idea fully. I will try to exlain what i have found out so far.

    To keep everything simple and stripped down to only the bare essentials, let's discuss about it in one-dimentional universe.

    Black line is our one-dimentional universe. It has length but it has no width and no height.

    If the spaceship warped that universe, it would look something like this.

    Left red point is the starting location and right red point is the destination. The distance between green points and red points is always the same for those beings living in that universe, but we ,who are outside of that universe, see it as it is on the image.

    Problem emerges here. Let's say that somebody just warped this one-dimensional universe and has stretched the universe so much that on this graph he would be quite close to his destination when we, the outside observers, observe him. He could be close when we looks at the bent universe, but inside his universe he sees no change and the distance is still the same. And if he wants to reach his destination, he would still have to travel the entire distance, which doesn't really explain, why he needed to warp the space in the first place.

    Question is, what am I missing?
  2. jcsd
  3. Nov 19, 2013 #2


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    Warp drives were invented on a 1960's science fiction TV show.
  4. Nov 20, 2013 #3


    Staff: Mentor

    You are missing the time dimension. If you look at the Alcubierre metric you see that there is a dx dt term. This term is essentially what lets the traveller take a shortcut. Remember, in GR we are interested in the curvature of spacetime, not just space.

    EDIT: also GR deals with intrinsic curvature. That is, curvature that can be measured from within the universe, not just to some outside observer. A 1D space cannot have any intrinsic curvature. So you always need at least 2D to talk about curvature.
    Last edited: Nov 20, 2013
  5. Nov 22, 2013 #4
    Didn't Alcubierre come up with a proof of concept though? The caveat being that it requires unfathomable amounts of energy and exotic matter that may or may not even exist?
  6. Nov 22, 2013 #5

    Simon Bridge

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    Does it matter what you call the unobtainium?
    A"proof of concept" would require a demonstration that the unobtainium can actually be obtained, at least, in principle.
    AFAIK, there is research to see if the casimir effect can be exploited as negative energy for the purpose.
    Note: energy and matter are the same thing.

    The drive basically makes a space-time bubble... the bubble travels.
    Per the original question... you are basically asking how to get out of the warp bubble once you've reached your destination.
    AFAIK nobody knows.
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