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Artificial gravity

  1. Apr 27, 2008 #1
    Every spaceship in sci-fiction movie I watch has some kind of artifical gravity. But is that possible? Are there any theories on how can be some kind of artificial gravity created without having a planet/black hole stucked at the bottom of your spaceship or everything magnetised?
    So far I only thought of some kind of centrifuge. S hip that spins rapidly creating a kind of gravity. Of course its not perfect, and far from sci-fi kind of ship mechanics, but only reasonable suggestion so far.

    My second question: Give it that people in sci-fi movies could somehow fake gravity to around 1g, shouldnt that also affect objects around the ship? You cannot stop gravity using walls.
  2. jcsd
  3. Apr 27, 2008 #2


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    There is no way to create true artificial gravity nor is there any theory that evens suggests a way. I'm not sure what you mean by your second question. In any scifi movie I have seen with "artificial gravity" it did affect everything in the ship.
  4. Apr 27, 2008 #3
    I said around the ship. Like asteroids or other ships.
  5. Apr 27, 2008 #4
    I think by "shouldnt that also affect objects around the ship?" he means, shouldn't planets, moons, etc that a ship with artificial gravity (e.g. Enteprise) is approaching or orbiting become disrupted gravitationally due to the fact that such a ship would be "leaking" its gravity outside the ship (since, as far as we can tell, walls, or anything else for that matter, don't block gravity)?

    Sheesh, get your physics book! Controlling artificial gravity is simply a matter of modulating the graviton stabilizers :)
  6. Apr 27, 2008 #5
    Ooops, I knew I should have reloaded this page before posting my lst comment.
  7. Apr 27, 2008 #6


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    If you're going to invent a magic technology for your story, why would you invent it with an undesirable side effect?

    Why not? You've already invented a fictional technology that can make gravity appear out of thin air, why could it not disappear into thin air?
  8. Apr 27, 2008 #7
    I dont necessiraly need artificial gravity, just something that acts like one. (as I mentioned the centrifuge)
  9. Apr 27, 2008 #8


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    It was not apparent to me that you were looking for ideas (presumably for a story). I got the impression you were simply asking about what you see in films.

    What level of technology are you looking at? Rotational gravity is probably the most likely source for any story set in the next couple of centuries at least - before any kind of artifical gravity mechanism is plausible.

    But there are other more intermediate methods to provide gravity. Have your spaceship accelerate at 1g for the first half of your trip then do a turnover and decelerate. The big setback to this method it that it requires the existence an almost limitless fuel source or highly efficient drive. That isn;t plausible anytime in the next century. It's also a bit awkward for short trips, dogfights or any other situation where the bulk of the journey's course is not reliably predictable.
    Last edited: Apr 27, 2008
  10. Apr 27, 2008 #9
    The centrifuge works fine. The larger the circumference the slower it would have to spin to get 1G at the outer rim. If it's large enough it will not make people motion sick either. As you move toward the center the centrifugal force will decrease and near the center the effective G force will be low enough people can fly with strap on wings.

    If you maintain enough constant acceleration you have your effective gravity without a centrifuge. If you maintained 1G acceleration you could get essentially anywhere in the observable Universe in roughly 20 years, assuming you could survive the radiation. You don't want to know how much time has passed back home. Our solar system wouldn't even exist anymore when you got back.
  11. Apr 27, 2008 #10


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    True, but one has to ask how much fuel will be required to power a ship's drive for 20 years straight. Not sure how well Bussards will work in intergalactic space.
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