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Quantum tunneling as transportation

  1. Jul 8, 2003 #1
    If there were a way to isolate a macro-sized object so that it fell under the heisenburg uncertainty rule, and then the wave function for the whole object would "un-collapse", do you think it would be possible to use this as a mode of transportation? When we see electrons move from one position from the next without ever being in-between it's called quantum tunneling. Would it be possible to quantum tunnel a spaceship to Alpha Centauri for example? I realize that's pretty "far out" and I'm sure others have thought of this before, but I think I'm in the right forum for such, hehe.

    A few questions would arrise...

    1) What are some guesses as to how we might completely isolate a macro-sized object from observation?

    2) Even if it's wave function "uncollapsed", how do you alter wave functions to be what you want them to be so that, once the object recollapses, it's in the place you want it to be?

    3) Would an isolated macro object's activity be TRULY random, as quantum particles are, or would they only APPEAR random but have "hidden variables"?

    4) Upon re-collapsing, wouldn't you have to worry about re-collapsing all of the constituent particles the same in relation to one another? Meaning, what if you could do all this, but when you recollapsed, every particle would be in a different random position throughout the area determined by it's wave function, effectively disintigrating the ship! Or, as with paired photons, might there be a way to link the fates of all constituent particles such that, when one's position is determined, the others immediately collapse in conjunction with it?

    Just wild speculation here for fun, but any thoughts you had would be welcome. :)
  2. jcsd
  3. Jul 8, 2003 #2
    I'd like to reply but

    you've been reading way to many simplistic popular accounts and have things all confused. Tunneling allows a particle to get through an energy barrier that classically it would not be able to. People and cats aren't describeable by wavefunctions because they change from distinguishable state to distinguishable state. Basically there isn't any "real" answer to your questions, so you can answer them any way you like.
  4. Jul 9, 2003 #3


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    Greetings !

    First of all, just in case, QT is limmited to c.
    As for using it for propulsion, the problem is statistics
    and randomness. To quantum tunnel a macroscopic object
    with a huge amount of particles all together and to a certain
    location of your choosing requires incredible odds that
    would probably be represented by by far the largest number
    you've ever seen. And QM says there is no possibility of
    controling the odds.

    Live long and prosper.
  5. Jul 9, 2003 #4
    Well, worst thing that can happen is that your di.k may get recollapsed to where your thumb was. Though, might become handy

    I wanted to ask, is quantum tunneling somehow related to entanglement?
  6. Jul 9, 2003 #5
    Re: I'd like to reply but

    Thanks for your reply, but no sh** sherlock. Of course people and cats aren't describable by wavefunctions. But I understood this forum to be for far out speculative stuff, which is why I didn't put it in the regular physics forum. My question specifically addressed the question of if there might be some way of getting macro-sized abjects to behave as quantum ones, which should have been a clue that I already understood that they normally don't. I'm not asking you to open your physics book and answer a supposed question about quantum mechanics. I'm asking you to speculate about possibilities not yet discovered - you know, imagination?
  7. Jul 9, 2003 #6
    Re: Re: Quantum tunneling as transportation

    Is quantum tunneling limited to c? What about other aspects of qquantum movement, like when an electron jumps from shell to shell - it's never inbetween at any point in time right? That amounts to instant teleportation. And then you have the famous paired photon experiments that calls into question locality. Am I interpreting something wrong in this?

    In any case, even if limited to c, you'd still have the advantage of traveling at c! :)

    Exactly how and where does it say this? We control the odds all the time. By directing our electron gun we're controlling the odds. We're moving the "bell curve" so to speak, in terms of changing where the more likely positions of the electrons would be. If this weren't true, we could never experiment on electrons because every time we let them go, they'd end up in some random part of the universe. For example, if I do the double slit experiment with photons in Nebraska, then I move my lab to California, I'm controlling the odds that those photons will be more likely now to be found, still in a random location, but most likely in my lab in California. So, our actions on the macro-level can and do change the shape of wave functions, which in fact is the very reason why anything acts and reacts in the universe at all.

    The question here is, might there be some way to artificially control or modify a wave function? You're telling me, and whatever entities exist a hundred, a thousand, even a million years from now, that YOU personally know they'll never discover some ingenius method of doing this?


    Peace and long life. :)
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