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Alcubierre Drive

  1. May 12, 2016 #1
    Hi Everyone,

    I'm about to write a novel on space exploration, and I've decided to use the Alcubierre Drive as the way the ship travels faster than light. I have the basics down about how it works, and I don't really want to go into too much detail in the book about it (most people are familiar with warp drives anyways) but I would like to have a little more of an understanding of how it works.

    From what I understand there are a few different ways it could work, but my question is specifically about tachyons and exotic matter. From what I've read if tachyons and the right kind of exotic matter were discovered this technology might be feasible. Would anybody here be able to give me a brief (or as brief as possible) explanation as to how this would work?

    Thanks in advance for your help!
     
  2. jcsd
  3. May 12, 2016 #2

    phinds

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    Wikipedia has an excellent article on it. Have you not read that?
     
  4. May 12, 2016 #3
    The general idea is that exotic matter could bend space-time in such a way that the ship is contained within a sort of bubble, and the position of that bubble is what moves, the ship itself does not need to move at all in relation to it's local frame of reference.
    Surfing is another analogy, the board is always just a few meters ahead of the wave peak but can be seen moving fast according to somebody watching from the shore.
    Although the math behind the idea is valid according to relativity there are a number of serious problems with it in practice:
    1. The sort of matter required for this arrangement is entirely hypothetical and there is no evidence suggesting it could actually exist.
    2. If it does exist it would represent a gigantic energy density similar in principle to black holes, and shifting the equivalent of black holes around is definitely problematic.
    3. At the end of the journey the ship has to return to normal space, that is the warp bubble has to be collapsed. The energy released in doing so approaches that of a supernova thus not only destroying the ship, but disrupting everything within a least a light year.
    4. Let's assume all the above are solvable, and the travel speed is considerably faster than light.
    In this case the ship becomes a virtual time machine, meaning that it could go to it's destination and immediately return, arriving some some time before it originally departed.
     
    Last edited: May 12, 2016
  5. May 12, 2016 #4
    It arrives after it started, and SEE that it arrived before it left the start point - most space travel SF thinks that, as well as some mathematicans, and Alcubierre drive is SF.
     
  6. May 12, 2016 #5
    Yes and the fiction part is the supposition that exotic matter with the neccessary properties could exist, which there is no evidence of.
    In star trek I think it was 'dilithium crystals', a rock like substance that could be mined on some planets, (it glows of course),
     
  7. May 13, 2016 #6

    chasrob

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    I read a paper on arXiv that (to paraphrase) explained a situation where a spaceship took off from the Cape, turned on the Alcubierre drive, went to alpha Centauri, and returned on warp drive. However, as explained above, it would arrive at the Cape before it would take off on the trek.
    Just a thought...
    Ok, its arrival would be the light, photons, of the actual ship. Not the ship itself, eh? So what would land at the pad would be an image. An image, that if you were to walk up to the pad, your hand would pass right through. I.E., the matter, baryons--the ship and crew--are actually between here and alph Cen.
    I must be wrong. Where?

    Wow, maybe I should not be ignoring all those ghost programs I hear about on cable TV :wink:.
     
    Last edited: May 13, 2016
  8. May 13, 2016 #7
    Hey, I just realized this topic was moved. Sorry for posting in the wrong forum. Thanks so much for you answers!

    To answer the first question, yes, Wikipedia was the first place I went naturally. I'm familiar with the basic principle of a warp drive. Space is contracted in front of the ship and expanded behind the ship, causing space time to move. The ship, encapsulated in the warp bubble, would seemingly travel faster than the speed of light to it's destination. If I'm wrong about this please let me know, but that seems to be the gist to me.

    I realize the problems associated with a warp drive and how it's probably not possible. Of course the book I'm writing is fiction so I'm not too concerned with that. I just want to present a form of faster than light travel that is somewhat plausible and based on fact.

    What I'm really concerned with is how exactly the ship would create the warp bubble. I've been researching Harold White's concept for an interstellar ship and would like to use a ship similar to this in my book. I'm just trying to figure out how exactly it would work. From what I can tell, some sort of exotic matter would travel around the rings to create the warp bubble. None of the articles are really all that specific about the properties this matter would need to have, but I'm assuming this matter would need to have a negative energy density, as that seems to be one of the problems in creating this technology. Also, I read this matter would have to travel at faster than light speeds, which would require the discovery of tachyons.

    So if I'm understanding this right, if you had some exotic matter with a negative energy density, and tachyons, and you used the tachyons to spin the exotic matter at faster than light speeds around the rings of the spaceship, would this create the warp bubble?
     
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