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First Steps Toward Artificial Gravity

Posted by samzenpus on Fri Mar 24, 2006 10:59 AM
from the stay-grounded dept.
CompaniaHill writes "Have scientists been able to artificially generate a gravitational field? Researchers at the European Space Agency believe so. "Small acceleration sensors placed at different locations close to the spinning superconductor, which has to be accelerated for the effect to be noticeable, recorded an acceleration field outside the superconductor that appears to be produced by gravitomagnetism. This experiment is the gravitational analogue of Faraday's electromagnetic induction experiment in 1831." The effect is very small, so don't expect to see it used in spacecraft any time soon. But the effect is still many times larger than the predictions of Einstein's theories. "If confirmed, this would be a major breakthrough," says [Austrian researcher Martin] Tajmar. "It opens up a new means of investigating general relativity and it consequences in the quantum world.""
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  • Forgot spaceships (Score:4, Informative)

    by bigattichouse (527527) on Friday March 24 2006, @11:03AM (#14988198) Homepage
    How about creating foam metals in a low gravity field?
    • Actually, this is an extremely good point- we might not be able to create a graviational field big enough for people to use, but what if it became possible to create materials that are currently only produceable in orbit? Could we make superhard/strong/elastic/conducting materials in a field like this? An interesting application. I wanna see this on 'How it's made' on Discovery Channel 3D HD in 2015 at the latest (^^).
          • by amliebsch (724858) on Friday March 24 2006, @11:53AM (#14988689) Journal
            If you can create gravity, it should be easy to create antigravity - i.e., free fall.

            I'm not so sure about that. Consider the following analogies:
            If you can create light, it should be easy to create antilight, i.e., darkness.
            If you can create sound, it should be easy to create antisound, i.e., silence.
            If you can create heat, it should be easy to creat antiheat, i.e., cold.

            • by ktulu1115 (567549) on Friday March 24 2006, @12:04PM (#14988786)
              Exactly.

              Cold is defined as the absence of heat. There is no such thing as measuring how "cold" something is - heat is the intrinsic property, cold is just a lack of it.
              Same thing with light.

              A lack of gravity does not imply anti-gravity. It just means that spacetime is flat in that particular region (and of course we know it's never truly flat, there's always some deviation). Anti-gravity would be akin to emitting gravitons with a "negative gravitational charge" - it's possible in theory and that's about it as far as we've discovered.
            • If you can create sound, it should be easy to create antisound, i.e., silence.

              Noise-cancelling headsets. They create silence by inverting the external waveform. Effectively "antisound"

              If you can create heat, it should be easy to creat antiheat, i.e., cold.

              Refrigerator?

              You have a point on the first one, however, and it's true that neither of those technologies are particularly "easy". Nevertheless, they're possible.
    • by Rude Turnip (49495) <valuation&gmail,com> on Friday March 24 2006, @11:14AM (#14988308)
      I'm not positive, but I think this can be accomplished readily today using a cat, a large rubber band and some buttered toast.
      • by markana (152984) on Friday March 24 2006, @11:58AM (#14988731)
        This method has never worked out in practice - it's only good for producing spinning, suspended cats.

        If you try to attach a shaft to the cat to transfer the rotational energy, the cat will stop trying to land on it's feet, and cling to the shaft. Thus no work is produced.

        Attempts have been made to glue magnets to the cat, which is then suspended in a coil. However, it appears that the natural static charge produced by the cat seems to cancel out the expected induced current.

        Experiments are continuing with *shaved* cats. I'm thinking about publishing some preliminary results, in hopes of winning an IgNoble.

  • by rubycodez (864176) on Friday March 24 2006, @11:06AM (#14988219)
    but a "gravitomagnetic one", which is a field that moving objects with "gravitational charge" (i.e., anything that produces gravitational force) make. it acts to repel or attract other gravitational charges. Still a huge discovery if true, could lead to inventions like (non-electromagnetic) "artificial gravity" or "force fields" or "levitation fields"
    • Heim theory? (Score:4, Interesting)

      by Balinares (316703) on Friday March 24 2006, @11:47AM (#14988617)
      Please excuse me if I'm asking something stupid, but does this relate with the Heim theory [wikipedia.org]? I recently a very interesting paper about its possible use in space propulsion [hpcc-space.de], but I can't tell if this article is about the same thing, not being much of a physicist. :)
      • by Valdrax (32670) on Friday March 24 2006, @12:57PM (#14989268)
        What you're asking is not stupid, but where you're asking it might be. It's highly doubtful that anyone here on Slashdot knows anything more about Heim theory than what the Wikipedia tells us. It's obscure and mostly understood by German speaking physics doctorates. (I challenge you small handful of physics experts on Slashdot who might have actually read his math and understood it to prove me wrong.) Fortunately, Germany is part of the ESA.

        However, from what I've read on "teh intarweb" from laymen speculators about Heim theory, his theory does supposedly predict that a rotating magnetic field would have a gravitational effect.

        Another physicist, Dröscher, has taken his theory further to say that in a similar setup -- a rotating ring above a superconducting coil -- could theoretically lift a 150-ton spaceship with a magnetic field of "only" 25 Tesla. He also claims that this might allow "hyperspace" travel where the speed of light changes, so I -- in my layman's knowledge of physics -- put Dröscher in the crank science box. You can read more about it in this New Scientist article. [newscientistspace.com] Take it with a good-sized chunk of rock salt.
        • by snowwrestler (896305) on Friday March 24 2006, @07:30PM (#14991944)
          Remember, every generally accepted scientific theory today started life as a fringe theory that the general consensus held was wrong. This is why groups like the NSA, DARPA, CIA etc continue to investigate "stupid" stuff like teleportation, mind control, hyperspace, gravity control, etc. 99% is probably BS, but there's a good bet that some fringe theory or phenomenon today will evolve into generally accepted wisdom within the next 50 years. If you're not looking at the edges of science you won't see where its reach is expanding.
  • Because it seems to me that the only way they could be certain it was gravitational influence and not some other phenomenon is if they also saw an apparent increase in the mass of the system.
      • by SpottedKuh (855161) on Friday March 24 2006, @11:24AM (#14988398)
        You're kidding, right? Mass is independent of gravity. That's second-grade knowledge.

        I believe you misunderstood the parent of your post. If I understand that post correctly, he's referring to Newton's gravitational law. It states that the gravitational force between Object A and Object B is directly proportional to the product of the two masses.

        So, in other words, your parent was asking: If we assume that the distance between two objects remains constant, as does the gravitational constant of the universe, shouldn't there be an increase in the mass of one of the objects to account for the gravitational force increasing?

        Or, put more simply: Did the spinning superconductor experience an increase in mass (somehow?), or was it the universal gravitational constant that was (somehow?) affected by the spinning superconductor?
          • Neither. Apparently, you've been asleep since the beginning of the 20th century: Newton is WRONG.

            Wow, someone feeling a little snarky this morning? I didn't say that I agreed with the grandparent in my previous post -- I do remember some high school physics. I was just attempting to do some justice to the thread that he started by helping to clarify his point. After all, his post (though scientifically outdated) raised a question that at least deserved a civil discussion.
  • by jandrese (485) * <kensama@vt.edu> on Friday March 24 2006, @11:08AM (#14988241) Homepage Journal
    Maybe there is something to all of those internet kooks afterall? This is hardly the first time I've seen talk of creating (or nullifying) gravity by spinning superconductors around, sometimes with electromagnetic charge and sometimes without.

    The problem usually comes when someone wants to see the experiment replicated. For some reason the effect always seems to go away when other people are looking. Or worse, other people notice things like "you've got a lot of evaporating liquid nitrogen flying past your mass sensor, isn't that going to affect the readings?

    Still, effective anti-grav in my lifetime would be quite a breakthough.
    • Like cold fusion, extraordinary claims require extraordinary evidence, so I will wait for tons of verification before getting too excited.

      Wouldn't it be funny if it turns out the scientists forgot that they were spinning their superconductors though Earth's magnetic field and thus generating a current which in turn caused their readings...
    • The problem usually comes when someone wants to see the experiment replicated. For some reason the effect always seems to go away when other people are looking.

      Of course! Don't you know that one of the basic tenets of quantum physics is that the observer always affects the experiment?

  • by to_kallon (778547) on Friday March 24 2006, @11:09AM (#14988251)
    "It opens up a new means of investigating general relativity and it consequences in the quantum world."

    but i'm running scared [imdb.com]
  • Yevgeny Podkletnov (Score:5, Informative)

    by volts (515080) on Friday March 24 2006, @11:11AM (#14988275) Homepage
    This sounds like the work of Yevgeny Podkletnov [bbc.co.uk] He claimed to have countered the effects of gravity in an experiment at the Tampere University of Technology in Finland in 1992 using a spinning super conducting ceramic ring.
    • by quanminoan (812306) on Friday March 24 2006, @11:27AM (#14988425)
      Podkletnov spun a levitated superconducting YBCO disk at high RPMs. As the story goes he walked into the room smoking a pipe and saw the smoke from the pipe rising in a column above the superconductor. Measurements showed a slight decrease in gravitational attraction above the superconductor. Of course, the science involved wasn't exactly careful (who would smoke a pipe next to equipment like that?), and he was dismissed as a crank.

      If you've read The Hunt for Zero Point by Nick Cook, Cook actually talks with Podkletnov about his "discovery". He then admits it wasn't a random experiment, but based off some Russian papers around WWII with some Nazi connections or something.

      So really it's pseudoscience, and i'm sure the scientists mentioned in the article were both aware of Podkletnov's work and at the same time careful not to associate themselves with him. Just because it's pseudoscience doesn't mean nothing will come of it - it just means it's really unlikely. If you're interested in this sort of thing I recommend reading Cook's book, he worked for a military journal before deciding to explore the world of pseudoscience (the book almost has a mystery thriller aspect to it).

      Podkletnov's Device: http://www.mufor.org/antigrav.html [mufor.org]

  • Hmm..... (Score:3, Insightful)

    by hawkmoon77 (957541) on Friday March 24 2006, @11:16AM (#14988326)
    It seems to me if you can take some manner of electricity, and produce some manner of a magnetic feild, and generate some amount of gravity... then doesn't it seem that there should follow a mathmatical equation that, sort of, unifies these observations in a grand and quantifiable way?
  • Path to Warp Drive (Score:3, Interesting)

    by Tempest451 (791438) on Friday March 24 2006, @11:16AM (#14988330)
    "IF" this is a real first step to artificial gravity (big if), then this is the natural progression to warp drive. Artificial Gravity - Gravity Shielding - Anti Gravity - Continuum Distortion - Warp Drive. My own scale.
  • Who cares? (Score:3, Funny)

    by jaysones (138378) on Friday March 24 2006, @11:18AM (#14988342)
    "It opens up a new means of investigating general relativity and it consequences in the quantum world."

    Who cares about that, where's my flying car?!
  • What? (Score:3, Insightful)

    by Moby Cock (771358) on Friday March 24 2006, @11:19AM (#14988357) Homepage
    Why is this called Artificial Gravity? They seem to have found a way to stimulate the generation of a gravitational field. But its still gravity. A radio transmitter stimulates the creation of an electric field (and the associated magnetic field) but we don't call that artificial electricity.

    Nevertheless, this is a very interesting discovery. Anyone have any other links?
    • Re:What? (Score:5, Funny)

      by Rob T Firefly (844560) on Friday March 24 2006, @11:30AM (#14988449) Homepage Journal
      but we don't call that artificial electricity.

      Obviously that's because if they let on that it was artificial, elitist snobs would demand the real thing.

      Like that time I got slapped for giving that lady artifical respiration..
  • by BewireNomali (618969) on Friday March 24 2006, @11:23AM (#14988386)
    ... but the caption is a bit sensationalistic.

    From the article, if I understand correctly, they are committing to the possible observation of a gravitomagnetic field as the explanation for discrepancies between expected and actual mass values. According to the article, all masses produce gravitomagnetic fields, so this artificial induction of one is no different from what anyone does when one moves mass around, right? It's just in this instance, the amount was so great as to be measurable in experiment.

    This is amazing, right? Isn't it that so much of gravity is known theoretically but not observationally? If we can directly gauge and measure gravitational fields, then we have taken the first critical step to manipulating them, right?

    Pardon any shoddy physics, but I was a chem guy, and only undergrad.

     
  • by dildo (250211) on Friday March 24 2006, @11:29AM (#14988445)
    Artificial gravity is not the real exitement around this experiment. The really important part is, you know, experimental evidence that may provide insight into the unification of relativity and quantum mechanics.

    I wonder what the editors were thinking:

    "Well, we can talk about the really exciting implications of this experiment that will be relevant to respectable physics ... or we could talk about some artificial gravity field thingy that will make crackpots and sci-fi fans excited. Well, it looks pretty obvious. Defer to the crackpots."

    How long before some crackpot on the threads says: "Well, if you just spin the disk backward, logically it should follow that the artificial gravity will turn into anti-gravity! I have made the greatest scientific discovery since Einstein! Wait... I better be quiet about this before the oil companies and government agencies try to sabotage me, just like they did with my zero-point energy machine and my perpetual engine (I'm still working on getting the lubricant working correctly...)"

    Nice job, guys.
  • Orginal Paper Here (Score:5, Informative)

    by spiro_killglance (121572) on Friday March 24 2006, @11:35AM (#14988498) Homepage
    Hi, i found the paper at the Los Almos pre-print archive.

    http://arxiv.org/abs/gr-qc/0603033 [arxiv.org]

    Actually, i think i believe the experiment, but i don't
    think i believe the interpretion, as the article and
    the above paper state, this effect is 10^30 times stronger
    than the gravitation force you'd expect from too small
    chunks of matter. I think they've discovered a new force
    all together.
    • by SiliconEntity (448450) on Friday March 24 2006, @01:37PM (#14989564)
      Thanks, that is a good reference and does answer some of the questions that have been posed here.

      They measured accelerations with commercially available accelerometers. These were placed into steel boxes to act as Faraday cages and block EM radiation. They ran the experiment many times with non-superconductors and with the superconductors too warm to super-conduct, and found no effects.

      There were no effects with high temperature superconductors, which their theory (a non-standard theory) predicted. There were also no effects when high-temp superconductors were lowered to liquid helium temperatures, which they also predicted.

      The only effects they saw were with low-temp superconductors, niobium and lead. There were no effects above their superconducting temperatures.

      They basically saw two effects. When accelerating a spinning superconducting ring, accelerometers located near a ring segment recorded an acceleration opposite to that experienced by the ring segment. So for example if this piece of the ring was spinning north, when they sped it up the accelerometers showed a southward force, and when they slowed it down the accelerometers showed a northward force.

      The strongest reading was by an accelerometer inside the ring, but one located just above the ring was almost as strong. This was actually contrary to their (non-standard) theory, which predicted that the force should be mostly localized to the ring plane. But since their theory is completely blue-sky and non-standard, that perhaps doesn't mean too much.

      The other effect they saw was with a constant spinning speed, lowering the temperature from non-superconducting to superconducting. As they passed through the critical temperature, the accelerometers again felt a force. It was noted that this force was in the opposite direction from the acceleration force, which I believe was also contrary to their (non-standard) theory.

      They also briefly mentioned Podkletnov, but only to say their results were "very different" from his. They also said that they did not see any signs of the effects he reported, to the limits of their measurement. I would note that I think Podkletnov used a spinning disk while these guys used a spinning ring.

      Overall it looks like a very careful experiment that did eliminate most sources of error. However the measured values were close to the noise limits of the accelerometers, which is always a little suspicious in science. The experiment definitely looks ready for replication. If it works it will turn gravitational theory on its head. There is no theory in existence that can account for these results. Not general relativity, not quantum gravity, and not even these guys' non-standard theory will work. Something completely new will be needed.
  • Slashdot had an article on a "hyperdrive" paper [slashdot.org] which is based upon Heim Theory [wikipedia.org]. Heim theory postulates EM-gravity coupling via the gravito-photon, and the experiment the Heim researchers recommended to produce gravito-photons [slashdot.org], and thus produce gravitational effects, sounds similar to what this article is describing.
  • by twifosp (532320) on Friday March 24 2006, @11:51AM (#14988665)
    I wish the article had more technical information on why they think it was a gravitational field and not a electrical magnetic field. I'm not questioning it without additional information, although the physicist (albeit amateur) in me wants to.

    Questions I'd like to see explained:

    It states that the acceleration is 100 millionths that of Earth's gravity. How was that measured? Against what constant?
    What was the effect on nearby matter placed in the field?
    If the type of matter was capable of it, was the matter polarized (possible indication that it's a electromagnetic field).
    And most importantly, what happens to radio waves as you fire them across the gravitational field? Cassini-Hyugen's experiment demonstrated that waves propagating at C will behave according to GR (spacetime bending) when shot across gravity fields. This behavior is different from electromagnetic influences, so it seems like a great validation test.

    This is fantastic news and I hope it turns out to be a valid gravitational effect. Studying this phenomenon could open up new doors in physics.

    Give us more details! I'm curious!

    • Its one small step for man, one slightly more difficult giant leap for mankind.
    • They won't be able to leap as far with it turned on though...
      • I you were building superstructures in space, yes. If you are trying to build something the size of the space shuttle, or even the ISS, spinning is not going to work. Besides, space travel is not the only place that artificial gravity would be useful. How about gyms. How about if being able to create artificial gravity leads to advances in deflecting or shielding of gravity. What if it leads to figuring out a way to make a repulsion as opposed to the normal attraction.

        While spinning is still probabl
      • Re:Awesome (Score:5, Informative)

        by bev_tech_rob (313485) on Friday March 24 2006, @11:17AM (#14988336)
        You haven't been keeping up on your Trek manuals, have you? The Inertial Dampening System predicts the adjustments it has to make when the command to jump to warp is issued. With weapons impacts, those are not predicted. The system can only REACT, therefore you get the shaking and jolting...
        • Re:Awesome (Score:3, Interesting)

          Oh come on, you can see it form up (beam weapon) any computer worth its salt could predict where it's going to fire and the torpedos have a trajectory it could predict the impact point precisely.
          • Re:Awesome (Score:3, Funny)

            by Anonymous Coward
            The tachyon reverse polarity quantum flux adds a degree of unpredictability to the energy output, dumbass. Though the heizenburg compensator is at full pelt, you aren't going to get the compensatory power fluctuation to work perfectly.

            Any energineer worth his brains would recognize that nanites would provide this kind of appropriate, precise energy output readout, but of course, deployment of such self-aware entities increases chances of a artificial intelligence takeover, which would suck.
            • but of course, deployment of such self-aware entities increases chances of a artificial intelligence takeover, which would suck.

              You must have missed several episodes.

              All you need to do is ask it to do something impossible, like calculating the last digit of pi, find an intelligent actor, or correctly fill out a tax form, and it will self-destruct.

              Be sure to stay far away when it does, because it usually makes a large mess. You do know that computers are always built out of explosives, don't you?
          • Well even if it could predict where it would be fired that doesn't mean it can tell how strong or weak the impact will be.

            If it over corrects it would damage the crew inside, who knows, maybe it is correcting and the shaking and such isn't as bad as it would be otherwise.
    • Short answer: go read about general (not special) relativity.

      Slightly longer answer: gravity is essentially the warping of space-time by the mass of an object. You can think of it as being like putting a heavy object on to a trampoline - the surface is pulled down under it. If you put a ball on it near the object, it'll roll down the sheet towards it.

      Gravity is a bit like that, but in three dimensions.
    • by meringuoid (568297) on Friday March 24 2006, @11:33AM (#14988479)
      The really interesting thing was the gravity (or a force of some kind) would pull you towards the crator. It would pull you so strongly towards the crator that you could lean opposite to the force (crator) at an almost 45 degree angle and you would not fall.

      My guess is that it was a perspective trick - like you sometimes get in funhouses, you know? The slope was steeper than it looked, and your brain interpreted the conflicting information from your eyes and your inner ear as a horizontal force.

    • Re:Not quite. (Score:5, Informative)

      by S3D (745318) on Friday March 24 2006, @11:47AM (#14988618)
      The claims are disputed and have not been verified by similar experiments.
      And your sources ?
      Similar experiment that disputes results of this one. http://esamultimedia.esa.int/docs/gsp/Experimental _Detection.pdf [esa.int]
      You should read the article you are citing. That is the exact experiment, that mentioned in TFA - Martin Tajmar et al experiment, which show anomalous gravimagnetic effect in the superconductive niobium ring which can not be explained by General Relativity, but can be explained by analogy between gravitons and photons.