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First Steps Toward Artificial Gravity 470

Posted by samzenpus 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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First Steps Toward Artificial Gravity More

First Steps Toward Artificial Gravity

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  • Forgot spaceships (Score:4, Informative)

    by bigattichouse ( 527527 ) on Friday March 24, 2006 @12:03PM (#14988198) Homepage
    How about creating foam metals in a low gravity field?
    • oops meant to say "Forget Spaceships".... I'd be interested in materials science that could be possible in low gravity fields.
    • 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 (^^).

    • Re:Forgot spaceships (Score:5, Funny)

      by Rude Turnip ( 49495 ) <valuation AT gmail DOT com> on Friday March 24, 2006 @12:14PM (#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.

  • not a gravitational field (Score:5, Interesting)

    by rubycodez ( 864176 ) on Friday March 24, 2006 @12:06PM (#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 @12:47PM (#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. :)

      • Supposedly, yes, Heim theory. (Score:5, Interesting)

        by Valdrax ( 32670 ) on Friday March 24, 2006 @01:57PM (#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.

        • Not too much salt though (Score:4, Insightful)

          by snowwrestler ( 896305 ) on Friday March 24, 2006 @08:30PM (#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.
      • I just realized after getting halfway through the paper you linked that it's by Dröscher himself, and it's describing the very loop + torus device and hyperspace transition mentioned in the New Scientist article that I linked.

        Page 15 gives a picture of the device, and sections 3.3 & 3.4 give the "vague description" of "hyperspace" travel that the article mentioned. It has to do with the absorption of positive gravitophotons (a Heim theory predicted particle for the interaction between gravity and

      • Re:Heim theory? (Score:3, Informative)

        by ceoyoyo ( 59147 )
        This doesn't require anything outside of general relativity. GR predicts that if you accelerate a mass you'll get a gravito-magnetic field just like if you accelerate a charge you get an electromagnetic one. Heim theory predicts that there is a linkage between electromagnetism and gravity, specifically that you can use one to create the other. That idea could potentially explain why they observed a greater force than expected from pure general relativity.

        However, the scientists who measured this effect h

    • 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.

      Gravitational charge is called "mass". The force carrier (analog to the photon in EM) is the Higgs boson. No one yet has linked EM, or the nuclear forces to gravitation. Smart theorists like Ed Witten [ias.edu] are trying like heck through M Theory. It is very unlikely that the solution to the problem would co

  • Did they detect an increase in mass? (Score:4, Interesting)

    by mark-t ( 151149 ) <markt.nerdflat@com> on Friday March 24, 2006 @12:07PM (#14988236) Journal
    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.

  • More spinning superconductors (Score:5, Insightful)

    by jandrese ( 485 ) * <kensama@vt.edu> on Friday March 24, 2006 @12:08PM (#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.
    • The difference between a kook and a scientist is the testing and documentation. It's easy to conjour up some "radical new idea that will shock scientists", it's something completely different to actually PROVE it.
      • "We ran more than 250 experiments, improved the facility over 3 years and discussed the validity of the results for 8 months before making this announcement. Now we are confident about the measurement," says Tajmar, who performed the experiments and hopes that other physicists will conduct their own versions of the experiment in order to verify the findings and rule out a facility induced effect. I vote not enough testing :)
    • 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?

    • 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.

      Well, in the real world, experiments are difficult and there is absolutely no guarantee that an experiment which works sometimes can be replicated with certainty on demand. An experiment may work once, then the researcher spends a month trying to get things working again, then it works, then the researcher spends another month trying to get things w

  • Not again! (Score:2, Informative)

    by Tempest451 ( 791438 )
    Artificial gravity has been dangled in front of our noses for years, by alien nuts, pseudo-scientist, and garage engineers. Like cold fusion and zero-point energy, it's always much-adu-about-nothing. Ya know what, just park a starship in orbit before you tell us about another "break-through" in artificial gravity.

  • i don't know about you guys, (Score:5, Funny)

    by to_kallon ( 778547 ) on Friday March 24, 2006 @12:09PM (#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]

  • A different approach towards artificial gravity (Score:2, Funny)

    by Anonymous Coward
    I've been doing research on this too, but from a different angle. Instead of using spinning superconductors, I've found that by collecting a large amount of mass together in one place, I can create a gravitational field. My current experiment has collected 7.2×10^15 kg of material in one place and there is definitely an effect.

    I am working on a larger test with 5.9736×10^24 kg of mass that seems to give gravitational field strengths that are roughly the same as we are used to.

  • Yevgeny Podkletnov (Score:5, Informative)

    by volts ( 515080 ) on Friday March 24, 2006 @12:11PM (#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.

    • Re:Yevgeny Podkletnov (Score:5, Interesting)

      by quanminoan ( 812306 ) on Friday March 24, 2006 @12:27PM (#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]

  • As my grandfather always used to say:

    "Gravity? We've got plenty of that already! Now, make me some anti-gravity, and I'll say you've got something!"
  • Can anyone explain what exactly gravity is, how mass creates it and how an object exerts a force on other objects through gravity? Ive always been under the impression that while we know gravity *exists* and that there is a direct strength linkage to the mass of an object, we dont actually know much about it at all unlike magnetism etc. Am I under a false impression?

    • Re:What is gravity? (Score:3, Informative)

      by Tim C ( 15259 )
      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.
    • If we return to the oft-used balloon analogy, imagine that the universe is two dimensional and laid out on the surface of a large balloon. The balloon (space time) is expanding. Anything that has mass is like a piece of tape stuck to the balloon. The tape resists the expansion of the balloon, creating the two-dimensional equivalent of the other oft-used analogy, a depression made by a bowling ball on a trampoline.

      That depression, that resistance to the expansion of space time, is what we perceive as grav

  • Hmm..... (Score:3, Insightful)

    by hawkmoon77 ( 957541 ) on Friday March 24, 2006 @12:16PM (#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?
    • While its obvious the parent is being sarcastic, the theory is the Grand Unification Theory [wikipedia.org] which stipulates that all those cool forces out there are like electricity, magnetism, nuclear decay, gravity, and loads of other cool stuff are related. The point is that the experiment is interesting because it suggests a way to relate gravity to other forces, which if I remember from an episode of Nova I saw on PBS +10 years ago, is something that is very hard to do.

  • Path to Warp Drive (Score:3, Interesting)

    by Tempest451 ( 791438 ) on Friday March 24, 2006 @12:16PM (#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.
    • Don't forget, we can power our "Mr. Warp" drives with cold fusion reactors.
    • "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.

      Quite right. But don't go down to the local Boeing factory with your copy of the Star Trek Technical Manual just yet. Run the numbers first. How large a (simulated) mass or antimass must you assemble to construct the Alcubierre warp field? How much energy does that equate to?

      Can't remember the exact am

  • Number Games (Score:2, Funny)

    by jotate ( 944643 )
    [...] the measured field is a surprising one hundred million trillion times larger than Einstein's General Relativity predicts.

    It's been a while since I took a math class but I believe one hundred million trillion is roughly equal to a gajillion.

  • Who cares? (Score:3, Funny)

    by jaysones ( 138378 ) on Friday March 24, 2006 @12:18PM (#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 @12:19PM (#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?
  • I'm overweight! I need an antigravity field!

  • I'm not that bright... (Score:3, Interesting)

    by BewireNomali ( 618969 ) on Friday March 24, 2006 @12:23PM (#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.

     
  • Before realising it was coming from ESA - European Space Agency I thought it was another article about McDonalds.

  • Communications may be a more important application than spacecraft. If it is hard but possible to detect artificial gravity sources fluctuating at a particular frequency, we would have a transmitter/receiver pair that is (a) hard to detect; (b) not blocked by much of anything, e.g. usable by submarines, deep-shaft miners, and networks that don't want to either lay cable or launch satellites.

    • (a) hard to detect; (b) not blocked by much of anything, e.g. usable by submarines, deep-shaft miners, and networks that don't want to either lay cable or launch satellites.

      I'm sorry, but you kind of lost me at "hard to detect".

      If it's hard to detect, wouldn't that make it hard for submarines, miners, and networks to actually use it?

      Last time I checked, things that were hard to use don't generate a lot of demand for their use.

      I mean, while it might come in handy for nations waging war on enemies incapable o

  • Slashdot misses the point again (Score:5, Insightful)

    by dildo ( 250211 ) on Friday March 24, 2006 @12:29PM (#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.
  • So, we just install a few million of these tiny spinning superconductors under the floorboards of a spaceship, and eureka! artificial gravity.

    So what would the gyroscopic effects of millions of tiny spinning masses be on the spaceship? Would these effects be bigger or smaller than the gyroscopic effects of a large spinning habitation module creating artificial gravity through centripital means?

    What would happen if we spun all the little buggers the other way? Would they go from suck to blow?
  • Oh christ, not Podkletnov again.

  • Orginal Paper Here (Score:5, Informative)

    by spiro_killglance ( 121572 ) on Friday March 24, 2006 @12:35PM (#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.

    • Re:Orginal Paper Here (Score:5, Informative)

      by SiliconEntity ( 448450 ) on Friday March 24, 2006 @02:37PM (#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.
  • I remember reading about this in Wired magazine a long time ago, some Russian guy claimed to have done it, and everyone dismissed him as a crackpot.
  • Relativistic mass is gravitational mass (a body approaching speed of light gains mass instead of speed + the heavier a body is, the stronger its gravity -> the faster the body moves the stronger its gravity). The movement doesn't have to be in a straight line, it can be equally well a circular trajectory. So if you get something to spin fast enough that material on the outer edges reaches linear speed near to c, it gets heavier and as result its gravity increases. By pumping arbitrary amounts of energy i
  • 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.
  • It's not clear that it's relevant to the experiment described in the article but magnetic levitation is already possible [science.ru.nl].

  • Gravity? Or something else? (Score:4, Interesting)

    by twifosp ( 532320 ) on Friday March 24, 2006 @12:51PM (#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!

    • Nobody addressed your last point:

      It's going to be AWFULLY hard to notice light bending in a gravitational field that small. I don't believe we can detect it in Earth's gravity, which is, apparently, 100 million times stronger than their field. We can see it in star light that skims the sun, and I think I read once that measurements have been made using Jupiter's gravitation field.

  • Gravitomagnetic radiation? (Score:3, Interesting)

    by Pfhorrest ( 545131 ) on Friday March 24, 2006 @02:47PM (#14989660) Homepage Journal
    I remember hearing about some of the early (Austrian?) spinning superconductor experiments which were largely dismissed many years ago, and I've been thinking about this sort of thing for a long time since I find it so fascinating, but as it's always dismissed as crackpottery, I don't really talk about it much.

    But here is a nice opportunity to ask some simple questions for anyone out there who understands the physics described here a little better than me...

    The effect in question is not gravitational per se, but rather gravitomagnetic, right? That is, it affects (and is produced by) moving masses in the same manner that an electromagnetic field affects and is produced by moving charges? It seems it would make perfect sense then, that one could create such a gravitomagnet via a rapidly spinning mass, just as spinning charges create electromagnets. I imagine that the reason we do not often notice such gravitomagnetic effects is because the force of gravity (or the amount of mass ordinary matter has, if you like) is so much less than the electomagnetic force. and thus much greater acceleration is needed to produce any noticable effect.

    The point of my inquiry here, however, is whether this electromagnetic-gravitomagnetic similarity extends further. Namely, if one takes an electromagnet and moves it back and forth, an electromagnetic wave is produced. A lot of these waves together we call electromagnetic radiation. Would it make sense, then, that a rapidly spinning, oscillating mass would produce gravitomagnetic waves, or gravitomagnetic radiation?

    I've been wondering if the Gravity Probe experiments that are described in lay news sources as trying to detect "gravity waves" from planets like Mercury were in fact measuring something like I described above. My question though, is what effect does / would a gravitomagnetic wave have? Would such a wave push or pull the object it collides with? My intuition says that, as photons push what they collide with, these gravtomagnetic 'particles' / waves would pull what they strike.

    Is that what "gravitons" are supposed to be?

    Someone with more knowledge of contemporary physics, please explain. Thank you.

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