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FTL travel: Do you think we can do it?

  1. Mar 7, 2008 #1
    I think YES!

    I'm a fan of quantum tunneling, or put simply, raising the speed of light.
    There have been a few successful experiments proving this, like the one performed by Günter Nimtz in 1994, who sent a FM broadcast of Mozart's 40th at 4.7 times the speed of light.
  2. jcsd
  3. Mar 7, 2008 #2


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    This topic has already been mentioned here very often and this interpretational error has been pointed out just as often.

    If you are such a fan of tunneling, you should have already noticed, that this is not about raising the speed of light at all. In the Nimtz experiment a light pulse is just sent through a nonlinear medium, which damps the back of the pulse more than the front, leading to a deformation of the pulse shape and nothing else. So the peak of the pulse travels faster than c, but no information is transported with this speed.

    Or as a comparison: A train is full of people. Their center of gravity is in the middle of the train. The people just sit around. As the train moves forward, the people in the back half are thrown out of the train. The people in the front just keep sitting. The center of gravity of the people still in the train is now not in the middle of the train, but it moved to the front half. Does that mean, that the people inside moved faster than the train?
  4. Mar 7, 2008 #3


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    There is no real ambiguity on this issue. The theories of physics that discuss the issue are heavily grounded in experimental evidence. No: true, macroscopic ftl travel is simply not possible.
  5. Mar 7, 2008 #4


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    Not only that, one is welcome to refer to a rather comprehensive review of such a thing that clearly challenges the notion that one actually was getting a superluminal tunneling:

    H. Winful, PRL v.90, p.023901 (2003)
    M. Buttiker and S. Washburn, Nature v.422, p.271 (2003)

    The most recent comprehensive treatment of this issue was published by H. Winful, where he again expanded upon his PRL paper and explained away the apparent superluminal paradox in various tunneling phenomena.

    H. Winful, Phys. Rep. v.436, p.1 (2006).

    Thus, the claim that there are a few "successful experiments" is not valid.

    And btw, I'm not just a "fan" of quantum tunneling. I used to actually performed a lot of it as part of my research project.

  6. Mar 8, 2008 #5


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    This sort of reminds me of when I was a kid (early 20's; age, not decade :tongue:) and still writing semi-professionally. I got about 1/8th way through writing a comedy SF movie in which I had some kids mount a tunnel diode on the front of a homemade spaceship. Since nobody who was likely to see it would know any better, I made up this crap about the diode would tunnel through superspace and the ship would follow it. Unfortunately, I ran out of funny far too quickly, so packed it in.
    Weirdly enough, it was about the same time that Disney's 'The Black Hole' came out. In retrospect, I think that my Mel Brooks type of science was more accurate than theirs. :rolleyes:
  7. Mar 8, 2008 #6


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    but the subversive thing is that there actually are devices called "tunnel diodes" and i wonder how much cred your scenario gets from there being real tunnel diodes, if they opened up an Newark Electronics or Digi Key catalog of the time.

    probably. 2001 (maybe 2010) was good, but these serious SF movies where sorta an oxymoron (you know, these recent ickies like Independence Day). but i do remember a Star Trek episode or two with "tachyons", "space-time", and other terms you might read in these pages.
  8. Mar 9, 2008 #7


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    That was actually the inspiration for the whole thing in the first place. I figured that I'd take the Tim Allen approach; if a tunnel diode supposedly works due to quantum tunneling, then just add more power for a bigger tunnel. :biggrin:

    And Gene Roddenberry was a very scientific fellow. Remember that he had been a commercial airline pilot and a cop before getting into show business. With the obvious compromises demanded to make a show viable and exciting, he tried to make things as realistic as possible.
  9. Mar 9, 2008 #8


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    They had movies in the '20s? Damn!
  10. Mar 9, 2008 #9


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    yeah, why not? makes perfect sense.

    ya know, it is hard to put together a reasonable SF premise that compels the audience to suspend disbelief to the level needed to get into and enjoy the film. either that or spoofs is the way to go.

  11. Mar 9, 2008 #10
    Silent movies. The ones with audio were called "talkies."
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