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Science

Levitating Liquids In Simulated Zero-G 102

Posted by timothy from the I-have-a-gravity-bridge-to-sell-you dept.
Ocean Quigley writes: "These researchers at Case Western University are making liquids float in magnetic fields, just as if they were in Zero G. By varying the strength of the fields, they can emulate changes in gravity. Take a look at: http://www.cwru.edu/pubaff/univco mm/liqbridge.htm." Very neat thinking on the part of these researchers -- don't fight gravity directly, but merely counteract it! Unfortunately, it doesn't look like a technique that can be applied to human beings yet, so you still need a plane or an elevator for your low-G experiences ;)
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Levitating Liquids In Simulated Zero-G More

Levitating Liquids In Simulated Zero-G

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  • Hell, it's done every spring at every Osco across the Midwestern US; for the display of fans, (which sell alot in the spring), you can toss a beach-ball onto the grille, the fan keeps it levitated, but the slipstream *around* the ball keeps it positioned on top of the grille so it doesn't float away, it's pretty cool to watch, unless you've ever worked at an Osco, and had to watch those damn balls bouncing around up there for the whole part of an 8 hour shift.

    Damn I'm glad I learned computers. That was a sucky job. Even raiding the liquor department after closing.

    if it ain't broke, then fix it 'till it is!
  • Millikan didn't use magnetic fields in his experiment though. His oil drop experiment used fine oil drops produced by aerosol and were suspended in air by an electric field and brownian motion.

    A very clever experiment. When the oil drops were aerosolized, they acquired an electric charge. By applying an electric field of the right magnitude, you can suspend the drops in air (until the charges are neutralized) or change the magnitude of the electric field and measure the rate the drops fall at. The experiment provided the first precise measurement of the magnitude of the charge of an electron.

    imabug
  • The device to which you're referring is called "inertial dampers" on the Enterprise. One of the technical writers whose job it is to explain the science behind the ST technology was once asked, "How do the inertial dampers work?" to which he replied, "Very well, thank you!"


    Quidquid latine dictum sit, altum viditur.
  • Could you use 2 magnetic fields of the same density, but of opposite polar strength, be used to rip something apart (or someone as someone mentioned)??

    A good reason to take intro E&M....the two magnetic fields would cancel each other out.
  • Try roller coaster :-)
  • > It would be far better to just focus all that energy out the back of some ship and be pushed along.

    No question about it! That's true in general, whether you're dealing with energy or mass, because gravity is such a weak force (it takes the entire Earth just to keep you from floating out into space - it would take another whole planet hovering above your head to levitate you.) The basic Newtonian action/reaction rocket propulsion approach will always outperform any gravity-based solution, unless we figure out some way to generate and focus "gravitons" on demand. Since we haven't ever even detected gravitons, and aren't really sure that they exist, that's gonna be tough.

    > e=MC2 - I read that as 'It takes an enormous amount of energy to create a small amount of mass, both have the same gravity footprint.'

    This is somewhat beside the point, but from a certain perspective it can be argued that energy only appears large in relationship to the equivalent mass to us, because we move around so slowly. In relativistic physics, the value for the speed of light, c, is often set to 1, which turns Einstein's equation into simply E=m, energy equals mass. Unfortunately, when you're stopped by a cop for breaking the speed limit, it doesn't seem to help to say "but officer, I was only doing 150 billionth of the speed of light!"

  • You'll notice I didn't say how big a planet was needed... But the advice of an old colleague of mine comes to mind: "You can't win arguments if you don't exaggerate!" :)
  • What is gravity pushing? What's the proof you have to pull off?

  • Re:Hmmm (Score:1)

    by QuMa ( 19440 )
    1) he's not talking about electromagnets, but normal magnetized material (Iron prolly though there are a few others that work too. (Like hydrogen :-) )) 1) even if you where to make it electromagnetic, You wouldn't need high voltage if you make the wires thick enough or short enough.
  • I remember seeing this actually done to a spider with no apparent ill effects. Well, the spider was pretty cheezed off, but...

    My .02
    Quux26
  • Well, if we're going to be pedantic, don't you mean zero g? I'm fairly sure the universal gravitational constant didn't get changed :-)
  • Really? Those must have been some tough astronauts, surviving unprotected in a vacuum then...
  • Sounds like those toys that suspend a ball with magnets. Would be a cool desk sculpture.
  • No...
    Andover was bought by VA Linux some time ago (remember)? So Andover doesn't actually exist as an entity. VA seems to be in the process of renaming Andover "OSDN", but the ownership isn't changing. This info is pretty easily obtained from the "About OSDN" link on OSDN's page.
  • ... looks like a lava lamp to me. ;-)
  • I know this is offtopic, but has anyone else noticed that the link at the bottom, "Comments are owned by the posters, The Rest Copyright 1997-2000 OSDN" (open source developers network)? It used to be Andover.net, not OSDN. When did this change? Why did this change?
  • Not only do we not know how it works, the current theorys about it are breaking down. For example all the GPS sats are slowing down differently than expected. Same with pioneer and voyager. There is hope to acutally measure this as the next ones have GPS recivers on them so we know exactly where they are. Another problem is that "realivitvty" keeps getting in the way of real science. One example is if you put a good atomic clock on a rocket and launch it, it slows down. Funny bit is that if you just start the engines but don't go anywhere, the clock also slows down. opps. The only real result I see out of any of the decent gravity expirments is that we are missing something critical.

    Years ago I looked into tring to see if a model of gravity pushing would reduce to the same formula we all knows controls newtownian motion. Simple modeling seemed to show that it does happen but my caclulus was much to poor to pull of the proof. I don't feel so bad because Newton was tring the same thing and failed.
  • That doesn't acknowledge the UK researchers who have a web site showing their magnetically levitating frogs.

    I didn't save the cite either, but I saw it about 12-18 months ago -- I was probably pointed there by /. even.
  • It'd be easier to just make remote controlled drones. There's other advantages to not having a cockpit too.
  • I don't get it.

    Oh, I'm sure 'energy' does have some gravity attached to it. But it would be far less than regular mass. Following this equation

    e=MC2

    I read that as 'It takes an enormous amount of energy to create a small amount of mass, both have the same gravity footprint.'

    It would be far better to just focus all that energy out the back of some ship and be pushed along.

    Later
    Erik Z
  • I know the article said that you can't levitate people, but what would happen if a person is inside a large plastic, bubble shaped container of water (in diving gear maybe), and this force is applied, wouldn't the bubble of water rise along with the person inside, and the person inside would hit the edge of the plastic bubble and start to rise, or is my logic wrong someplace.

    If this were possible many applications could be thought up, like having a large thing of water under an elevator to make an elevator operated by zero g.

  • <BLOCKQUOTE>
    "What we really need is to be able to create a mass in front of our starship and accellerate that mass, and let the mass pull the starship along via gravitational forces. We would experience no sensation of movement. "
    </BLOCKQUOTE>
    Close, but no cigar. The elevator effect remains.
    What you need to do is create a mass to move the <I>rest</I> of the universe, without disturbing your own inertial reference frame.

    Seriously, what is needed is something to accelerate your "inertial reference frame". Which is as tricky a concept as gravity. (How does going down a drain in deep space know if it is spinning or not?)

    CD
  • By T1000 I assume Happy Monkey meant the 'liquid metal' robot from Terminator 2. His subject line was "Poor Arnold"

    And besides, T1000 couldn't turn into a car, he can only transform into objects of the same size.
  • The ping pong ball would just shoot right up...not exactly the same thing...

    Interestingly, since the ping pong ball is a sphere it would have equal air pressure (assuming the ball is in the center of the air stream) as the air flows past the sides of the ball. The equal amount of force on the sides of the ball would hold it in the center of the air stream. What's more is, after the air flows past the ball, the air above the ball would have a negative pressure and, thus, would push back down on the ball. This negative air pressure is very weak, but it's strong enough to hold something as light as a ping pong ball, "levitating" it in the air stream. If the air blowing from the hair dryer is small enough, the negative presure above the ball, the small weight of the ping pong ball, and the airflowing by the sides of the ball act together to suspend the balls movement in the X, Y and Z planes.

    This is more just simple physics and an exercise in aerodynamics than it is an act of 'levitation'.

  • Great, now they can make swimming pools for those astronauts...
  • Don't create an anti-gravity field, create a different type of field of equal strength in the opposite direction.

    Makes a lot of sense in that context.

  • Freefall, goddamn you. Freefall. There is no zero-G.

    --

  • Have you tried it? Well, admittedly I haven't either -- will someone try this!? :-) Anyway, I have seen similar setups with little toys and (I think) at the science museum. An upward air stream can support hollow plastic balls, even if from a "point" source.
  • Without moving parts, too.
  • this is cool stuff! sorry i don't have anything more insightfull to say, but if i had some moderator points you'd get a few :).
  • he and another guy made fridges with no moving parts - just mercury, and an electromagnetic force. Smilar to this story (though using magnesium tetra.... instead of mercury)

    So, basically this story was about a researcher who is doing something with a high gee whiz factor, but that has been done before - many times - heck, the magnetized a frog in the Netherlands and suspended it years ago.

    Still, it looks cool :)

  • Magnesium chloride is not toxic or particularly hard to find. But it is also not paramagnetic, and as far as I know does not form a tetrahydrate. I supect what the article was supposed to say was manganese chloride tetrahydrate.
  • This could actually be a serious practical application, especially in military planes. Many maneuvers that today's planes could theoretical make are not possible because of the tremendous number of G's the pilot would be subjected to. Perhaps a strong magnetic field could be used to counteract some of that force, allowing the pilots to make even tighter turns.

    Of course, one issues would be size and power constraints. I'm assuming the apparatus to generate such fields is pretty unwieldy. But if it could be shrunk, and if a plane was designed to hold it, this could be an interesting experiment!
  • I saw on the Discovery channel over a year ago (and I think on wired news, too; search for it yourself [wired.com]). They levitated, besides water, frogs, crickets, dice, etc. It was quite a thing to see.

    But it appears this research is more than "my magnetic field is bigger than yours," this one applying to space travel and stuff. Interesting.
  • No, you are wrong. The sum of the vectors is zero. Really is a case of frame-of-reference.
  • Of course, if you are worried about the magnetic moment, you could just do this with a giant block of osmium.
  • Building a starship isn't a serious practical application?
  • it takes the entire Earth just to keep you from floating out into space - it would take another whole planet hovering above your head to levitate you.

    Not quite -- you're ignoring the inverse-distance^2 dependence of gravity. All you need is enough mass at the proper distance...

    But I suspect you knew that, and besides the concept is much more impressive the way you stated it. :)

    ---

  • Second, a Levitron, which you can buy for a couple of bucks. The working principle is rather complicated, though.

    I thought the principle was quite simple. If you place a magnet above another magnet, like poles towards each other, then, as a rule, the top magnet will flip over because of the attractive force between the unlike poles, so you can't levitate it that way. As a spinning top, particularly one with a fairly big moment of intertia (as in the Levitron) is very resistant to flipping over, it can't, so it's held up by the repulsive force between the like poles of the magnets.

  • It's only a question of time before Mathmos [mathmos.co.uk] announces a product line of 0G Lava Lamps...
  • Well since we now have "computer fashion" due to popular demand (*ahem* who?).. Why don't we get 0 G suits full of this anti G liquid? Then we could walk around into a 0 G lift shaft and crash into the roof in style. :) slyrp
  • Unfortunately, it doesn't look like a technique that can be applied to human beings yet, so you still need a plane or an elevator for your low-G experiences

    Unfortunately?

  • sarcasim on

    Yes, that would have been news -- a few hundred years ago! I think you'll find Maxwell pretty much had it figured out 100 years ago or so.

    sarcasim off

    Seriously what is the big deal? The only thing I can think of is maybe they got some ferromagnetic material to disolve in water. Couldn't we do that already? Other than that I think you will find that we knew about magnets for quite a long time.
  • Any reference to a flying T1000 needs a link to this. [berkeley.edu]

    They're really the same car.

  • Now T1000 can fly!
    ___

  • Hmmm (Score:1)

    by v4mpyr ( 185039 )
    Actually makes a lot of sense when you think about it. Ever see those toys in the science shops that have the floating magnets on a stick, or try to push two magnets together?

    Just imagine making roads out of magnetic material . . . we might be closer to those ``Back to the Future'' cars than we think. ;-)
  • I think OSDN bought out Andover thereby inheriting all the sites under its reign. &nbsp (a.k.a. Slashdot, Freshmeat and a whole schlew of others.) Interestingly enough, OSDN is actually using a modified version of Slash. :-)
  • Come on this is hardly an amazing bit of Physics, its simple magnetic field stuff, anyone with enough time, lots of copper wire and a big enough power supply could do it....

    I will be more impressed if someone manages to induce gravity rather than defying it.

    "Arse, Drink, Feck"
    Father Jack
  • how is this different from the original oil drop experiement done by Milikan?
  • What you need to do is create a mass to move the rest of the universe, without disturbing your own inertial reference frame

    Here's a simpler solution (created by some italian guy I cant recall right now... Talliaferro? Something of the sorts):

    a) Create a compression of space-time in front of the ship. An artificial black hole, if you wish.
    b) (This is the tricky part... or should I say, trickier?)Create an expansion of space-time behind the ship. Im not sure exactly how to pull this one off.
    c) The combination of compression and expansion of the space-time continuum (sp?) creates something like a space-time "wave", which the ship would be riding. Like space-time surfing, or something.

    The ship experiences no movement _at all_, since it's in the same relative position in the space which surrounds it. Therefore, no inertia. And since there's no theoretical limit on the speed of the space-time expansion/compression, you _could_ move this wave of space-time at a faster than light speed, from the POV of an outside observer.

    Of course, all of this space-time distorsions could possibly break havoc with the rest of the universe (or at least the places you space-surf by) but hey, getting there is half the fun, right?

  • This has nothing to do with any sort of general purpose counteraction of gravity using magnets, as the slashdot post would have you think.

    The fluids he's floating are filled with metallic particles that react to the magnets. Unless you can easily saturate your body with some special compounds that have magnetic properties, forget flying with this

  • This is very different from the ping pong ball case.

    In the floating ping pong ball case. The ball is being lifted (its flying) based on an external force. If you were in the ball you would experience the same sort of sensations you would in a an air plane (of course due to the size of the ball it would be like flying coach ;)

    You can rent time in silo shaped wind tunnels (mounted vertically) and fly like the ping pong balls. Very windy of course and noisy.

    These bridges are being supported almost on a atom by atom basis. If this was happening to you would would feel a very different. The sensation must be the same as wieghtlessness

  • There already exists a train using magnetic levitation, it's the german Transrapid [transrapid.de] (this is no new technology, it exists since the 1980ies). It can go as fast as 420 km/h (260 mph). Unfortunately industry and government couldn't agree on building it yet. There exists a test facility though and you can get a ride for a few bucks.
  • Just in defence of my own comment: I remembered King's rantings about alien spaceships and free energy machines. You may note that I also said I read books with some bad science sometimes. I have no doubt there was some bad science in this book.


    However, sometimes speculative science is:

    1)fun
    2)interesting
    3)possibly partly right
    4)a good excersize in challenging assumptions

    Free energy machines are, of course, impossible. However, getting a very large amount of energy in a local spot through the use of a smaller (maybe even much smaller) expenditure of enery may not be. Make the difference large enough at a cost that's acceptable (and feasible) and you may have what you need.

    Of course, S. Weinberg's statement that you made shoots the idea you could use "free energy" to SBN (some burning netherworld)...

  • IANAP (I am not a Physicist), but I'm an amateur mathematician, and I often read books that are probably full of bad science. So anything I say is suspect. But...


    There _is_ a way to mess with gravity. Concentrate enough energy in one spot, and you will bend space (why? Well, there's a mass-energy equivalence, and if you put mass in one spot, you bend space, causing gravity...right?). As everyone knows, you'd have to get a huge amount of energy, tho'.. so we need a source that's just massive. There's a theoretical entity called the "zero-point" energy that is supposedly available at any point in the universe (from activity of the "quantum foam" that's present even in a vacuum. No, I don't really understand it). The problem is, it flows orthogonal to any of the dimensions we live in (at right angles to reality, as Douglas Adams migh say). So, all we have to do is figure out some way to change the angle. Even a small amount of the tapped energy might be enough, causing I bend in space. Put the bend in the right place (say, a safe number of meters above your head), and adjust the magnitude, and you're floating.


    Unfortunately, this gravity source will not only affect you. Near as I can tell, many things in the near vicinity would be pulled straight toward you. Hope you don't have any large household appliances.


    And in case you're wondering, I got all this stuff from a book called "Tapping the Zero Point Energy" by Moray B. King....

  • Nope. In fact, I'm glad for both of them, and I'm certain most slashdot readers will also benefit more from reading those posts than mine. But your posts wouldn't have existed if it weren't for mine. I didn't post because I was sure the
    science was correct; I posted because I thought it was an interesting idea and might provoke educational thought or discussion. It did, with the help of the two posters. What I posted may be wrong, but I don't consider myself "shot down", and I'm not particularly embarrased.

    In short: I hope people DO read the replies refuting what I posted [slashdot.org]... both of them.
  • Hmmm... I meant to post this at the top level,
    but ended up replying to a comment. So I point
    you here [slashdot.org]. For starters, there _is_ a way to mess with gravity. Concentrate enough energy in one spot, and you will bend space ....why? Well, there's a mass-energy equivalence, and if you put mass in one spot, you bend space, causing gravity...right?....

    More info? Read the comment. [slashdot.org].

  • Good for the people who did that. But the common person has no use for levitating liquids. And even if we did, it would be so expensive that most people couldnt afford it.
    Andrew Rauss

  • Re:Hmmm (Score:1)

    by NSK ( 226742 )
    Yeah... and then you'd only have to wire up the whole road to a highvoltage outlet somewhere. Sounds pretty dangerous.

  • Well... (Score:1)

    by NSK ( 226742 )
    The problem with naturally (not generated by electicity) magnetic matter is that it gets worn out (I can swear you don't have any working magnets left since your childhood experiments). You have to have two + or two - poles which can repell eachother and thus you must have something that sustains it otherwise it will be gone in notime.
  • Levitating liquid metals has been done for many decades. It is a method for preparing high purity samples, especially reactive metals, without danger of contamination from a container. The levitation is not a big deal. It is the behavior of the levitated fluids that is of interest here.
  • Actually, I thought this was a fairly common physics demonstration. I even seem to recall some silly kid's game show I saw once in which they were levitating ping pong balls with hair dryers to accomplish something or other. It works.

  • Question. (Score:2)

    by Anonymous Coward
    How strong of a magnetic field does it take to kill a person?

    Could you use a very strong field and kill some one instantly as well as painlessly, or would it just be messy?
  • The problem is that you neglected to let anyone know this guy was a kook before you quoted his theory.


    - Jeff A. Campbell
    - VelociNews (http://www.velocinews.com [velocinews.com])
  • I haven't read the book you mention, but zero-point energy is one of those concepts, with a basis in real physics, which has become a favorite of crackpots and proponents of the paranormal, for which all sorts of possibilities are claimed with little theoretical basis or evidence.

    Scientific American has a fairly balanced article on the subject, Exploiting Zero-Point Energy [sciam.com]. By balanced, I mean it's probably excessively generous in allowing that there might be something in some of the crackpot theories of zero-point energy.

    The suggestion given about using zero-point energy to affect gravity makes no sense to me. If it was taken from that book, I would suggest that you consider the book highly suspect, or at least speculative to the point of fantasy.

    Most supposed exploitations of zero-point energy ignore what we really do know about it, namely that Heisenberg's principle means that by definition, it manifests in really, really small quantities. The only known and peer-verified effect that's commonly attributed to zero-point energy is the Casimir effect, which as described in the Scientific American article, is capable of generating mere nanonewtons of force - the weight of a blood cell in the Earth's gravitational field.

    Zero-point energy proponents make all sorts of assumptions about things that we can't possibly test, nor do we have any reason to believe that they're true. For example, the idea that there's an infinite reservoir of energy orthorgonal to the dimensions we live in, that might somehow be tapped. The zero-point energy of real physics implies nothing of the kind, and there is no evidence of this. This idea comes from a naive conception of energy and its creation - "there are very small amounts of energy everywhere in the universe at all times, therefore it must be coming from an infinitely huge reservoir."

    In fact, the best quantum theory interpretations imply that zero-point energy is actually created and destroyed in the vacuum, i.e. the energy does not lead a separate existence (as in a reservoir) outside of the particle-antiparticle generation and annihilation that occurs continually at the levels which Heisenberg's principle predicts. Further, these interactions are theoretically limited in size, since if they exceeded Heisenberg's limits they would violate what we know about conservation of energy. So what we really know about zero-point energy is that you would have to "farm" unimaginably huge volumes of space to obtain useful amounts of energy, and that there are any number of more practical energy sources around us.

    But let's assume I'm completely wrong and you could somehow extract large amounts of energy from an arbitrary point in space. It still wouldn't create the gravity warping machine described. Once fully present in our universe, this large amount of energy would radiate like any other large energy source - you'd effectively have created a small star in your vicinity, although one which burns without the need for pesky raw materials. Yes, this virtual star would affect spacetime (and therefore gravity) around it, but I suspect your elation at the levitation effect thus achieved would be rather diminished by your imminent demise as you and everything around you is fried to a crisp.

    Of course, regardless of its impracticality as a gravitational generator, being able to extract large amounts of energy from nothing seems like it might be useful. But, even if this were possible (and all evidence and current knowledge indicates otherwise), you'd still face the same problems that are faced by builders of fusion reactors - how to contain and tap that energy. After all, "hot" fusion is already capable of providing huge amounts of energy using minimal raw materials, without the dangerous waste produced by nuclear fission; but unfortunately, no-one has yet been able to come up with a way to actually implement a practical fusion reactor.

  • Zero G, in other words, when the net force applied to an object is 0G. G is a unit of force, equal to the force of gravity at earth's surface at the equator at sea level (right?).

    If you are in orbit, in a freefall (yes, orbit is freefall) towards earth, or out in the middle of interstellar space... you experience zero G, as in NO FORCE APPLIED.

    THank you.
  • Remember, this doesn't 'counteract' the force directly.. it acts on diamagnetic molecules and exerts force on them.
    It is not 100% equal to an opposing gravitational force.

    What we really need is to be able to create a mass in front of our starship and accellerate that mass, and let the mass pull the starship along via gravitational forces. We would experience no sensation of movement.
    OF course. we would also need to be able to create/destroy that mass at will (energy -> mass and vice-versa). I think this is how the aliens do it.
  • Where the heck are you going to get the 6 megawatts of power needed to run the 20 tesla magnet? And that's just to do a chamber 32mm across!
  • Actually, Maxwell had NO IDEA about this.
    According to maxwell, stable magnetic levitation is not possible.

    Maxwell did NOT know about diamagnetic effects.
    This is NOT about ferromagnetics at all.. it's about diamagnetics.

    Water is diamagnetic ALL BY ITSELF. Water exudes an incredibly tiny, but constant magnetic field.
    If an external field is applied, electronis in the water alter path to compensate, causing exactly the field necessary to repel.

    This is the exact same effect that is seen in superconducters, you just need vastly more power to see it.
  • Actuall,y you COULD use this effect to levitate a person.

    Considering the frog levitation experiment used
    a) a very tiny frog
    and
    b) 6MW of power.... to create a 20 Tesla field..
    how hard do you think it would be to levitate a 150lb human?
  • No.. because he's not dealing with a magnetic liquid. He's dealing with a diamagnetic liquid.. which is very different.
  • A friendly guide for reporters and editors on the correct use of our name.

    Our correct name is Case Western Reserve University.

    On second reference, simply use CWRU. It's that simple.

    We may also be referred to as Case Western Reserve, or even Case Reserve (especially if you're referring to our sports teams, the Spartans). Our name is a result of the federation of two previously separate institutions -- Case Institute of Technology and Western Reserve University -- more than thirty years ago. So our name is neither Case Western nor Case Western University (that's like "University of North," which is meaningless) nor are we just Case--unless referring only to the Case School of Engineering.

    [cwru.edu]
    http://www.cwru.edu/pubaff/univcomm/cwruname.htm

  • Hmm... (Score:2)

    by cr0sh ( 43134 )
    Pretty neat and all - kinda got me to thinking...

    What if you took some oil - maybe some relatively thick oil (gear oil?) and mixed in some iron filings, or powder.

    Would it be possible to set up a system similar to the "floating globe" thing (you know, where this metal sphere "floats" in the air - an electromagnet is controlled via a closed-loop feedback system measuring where the globe is vertically in relation to the electromagnet)?

    I know it wouldn't be rigid (being a liquid and such), so that would possible cause problems - but say that could be overcome - would the force needed to keep it suspended be extreme (as in as big as the floating frog experiment)?

    Just some crazy thoughts...

    I support the EFF [eff.org] - do you?
  • How strong of a magnetic field does it take to kill a person?

    I don't think that question has been answered. A magnetic field doesn't tend to cause subatomic particles to go ripping through a body the same way an electric field does. Small creatures such as frogs have been levitated in fields around 16 T, and as far as I know they appear to be unaffected afterward. However, strong magnetic fields do appear to disrupt natural development of frog embryos--the cells tend to divide in the wrong order, so to speak.

    At the moment, there is a big problem with trying to apply a really huge (order of magnitude greater than MRI) magnetic field to a human: the cylindrical space in which the field is strongest is pretty small. Maybe you could fit a couple of fingers in there, but certainly not a human head or torso.
  • The ping pong ball would just shoot right up...not exactly the same thing...
  • In Apollo13, they wer drinking juice (liquid) and it separated when in the Zero G environment of space. Wouldn't the same thing occur?
  • I was thinking the same thing
  • Okay I was reading a few comments and it suddenly dawned on me. Could you use 2 magnetic fields of the same density, but of opposite polar strength, be used to rip something apart (or someone as someone mentioned)??
  • I know that they would cancel each other out, at a single point at the very center, but as you get closer to each other magnet, the fields would become stronger. And since the average human being is 3 dimensional their bodies would be affected by the magnetic pull.
  • You actually tried using a hairdryer to levite a ping pong ball? The flow of air disapates as you move slowly out from the centre of the airflow. Now if the flow was constant at every point then it may be possible, but its not.
    The ball will go up and then come back down very quickly.
  • Well they do mention how this is different from other such exparments in the article:

    "While others have done similar work using techniques involving motors or by suspending a liquid within another liquid bath, countering gravity against a magnetic field has a multitude of advantages. He points out that with this technique scientists can study phenomena on incredibly fast time scales, down to milliseconds. Additionally, the magnetic approach allows the liquid or solid to float freely, unencumbered by the physical constraints of mechanically driven motion or the effects of a surrounding liquid bath."
  • anyone else think of this while they read it?

  • Just imagine making roads out of magnetic material

    And watch my laptop's hard drive get erased on the way to school.


    <O
    ( \
    XGNOME vs. KDE: the game! [8m.com]
  • Well, I used to work right next to a liquid helium cooled supercondiucting magnet all day long. Probably one of the strongest magnets around. My watch hated it (even in the next room) but my hemoglobin survived intact. Think >100T for any real trouble maybe?
  • Immediately I can forsee applications as a new type of mass chromatography column with all components in the liquid phase. What about reversing the net gravitational field such that the more massive analytes elute later, from the top? One could separate proteins, for instance, by carefully varying the fields. What if this type of thing were done with pressure and temperature as a variable? What about introducing an orthogonal ionizing or accelerating electric field? Also don't forget that other paramagnetic liquids such as liquid oxygen might be interesting for this.
  • i disagree with Mr.Sketch, i think the above should be moderated DOWN for its gross amount of pseudoscience and misinformation.

    Moray B. King starts out his book by telling the reader that earth is being visited by alien spaceships all the time. As if that were not enough to discredit him immediately he goes on in his book to explain how his lifelong goal has been to get people to build so called "free energy machines" (ahem...remind you of anything?? maybe the quest to build perpetual motion machines in the 19th century before thermodynamics came to light?)

    no one doubts that so called zero point energy exists. even the promenent physicist steven weinberg agrees with that. it has been proven to exist by the casimir effect http://www.sciam.com/askexpert/physics/physics44/p hysics44.html . though dont be so quick to assume it is going to solve the worlds energy needs. in the same interview with alan alda for the PBS program 'scientific american frontiers' S.Weinberg states that the total amount of "free energy" in the volme of space the size of the earth would be equal to about the energy in a gallon of gas. i suggest carl sagan's 'the demon haunted world' or michael shermer's 'why people believe weird things'.
  • I have an application that could potentially suit this technology, and it sounds easy enough to do at home once you have some magnesium chloride tetrahydrate, but does anyone have the following info:

    1) Is magnesium chloride tetrahydrate dangerous? Poisonous? Carcenogenic?
    2) Is it expensive?
    3) Is it difficult to get hold of?
    4) Is it a major component in some esoteric nerve gas such that my purchase of it would bar me from international travel for life? :-)
  • The most memorable zero-G liquid I ever saw was when that guy puked in Apollo 13. I'll never forget what barf look like in space (or at least in NASA's "Vomit Comet".

  • Besides being able to demonstrate molasses flowing uphill :) what practical applications come to mind for this?

    Off the top of my head, how about a new way to keep your car windshield clear from rain? Have a reservoir of highly-paramagnetic fluid which is continually fed through fine nozzles at the base of the windshield. Imbed microfine horizontal wires in the windshield. Pulse currents through the wires in a sweeping pattern up the windshield. Have a gutter at the top and recover the fluid. Filter out the water (osmotic filter?) and reuse the fluid.

    Hmmm, on second thought, migh this result in non-uniform depths of fluid on the windshield causing a fun-house mirror effect? In that case, create this on a smaller scale with a high-powered light shining through it and a computer-controlled sequencer to vary the strength and timing of the fields -- voila! Feed your favorite audio stream into the sequencer and you've got the latest in high-tech lightshow equipment for your next party! ;-)

    I'm curious what other /.'ers can come up with.

  • Definitely. This isnt really new, except for perhaps the scale of the levitation liquid.
    But Mullikan did it around 1910, and with equipment not nearly as fancy.

    You can buy something that can recreate Millikan's experiment here [telatomic.com].

    More information at : Mullikan's Oil Drop Experiment - RMWC [rmwc.edu]
  • If there have been any deaths due to strong constant magnetic fields it has probably been related to some classified project.

    I would have three major concerns if I were working with very stong magnetic fields.

    1) Are the fields in question constant fields. changing fields generate electrical currents when they cross anything that conducts electricity. (like humans, but wire works better)

    2) where does the energy go if the field accedentally fails. Power failures, shorting out the power supply outputs, dialectiric failures. Can cause huge power surges.

    3) Pregnant people and children. Could mess with growth and develpoment. (vaugely remember something about this somewhere.}

    I would guess that a rapidly changing magnetic field could be used as a murder weapon. The medical examiner would be very confused at first. However you might need millons of dollars of equipment that would not be portable. Also the electric company would know the exact time of death from the power consumption charts

    One of my Physics profs in college worked on prototype cyclotrons in the 50's. He told us about a power supply failure (something metal got across the power supply outlets IIRC) He did not feel anything, but there was a bang followed by a crash. A picture hung near the coils had the wire that held it up melted. It then fell to the floor. Check your spare change and dental fillings at the door !

  • This is an abuse of the system, becuase I'm blatantly picking the highest ranked comment and replying to it so this will be seen, but I thought this might be worthwhile enough to risk it. My comment was already posted once, but it's a bit farther down on the rankings.

    and IANAP (I am not a Physicist), but I'm an amateur mathematician, and I often read books that are probably full of bad science. So anything I say is suspect. But...

    There _is_ a way to mess with gravity. Concentrate enough energy in one spot, and you will bend space (why? Well, there's a mass-energy equivalence, and if you put mass in one spot, you bend space, causing gravity...right?). As everyone knows,
    you'd have to get a huge amount of energy, tho'.. so we need a source that's just massive. There's a theoretical entity called the "zero-point" energy that is supposedly available at any point in the universe (from activity of the "quantum foam" that's present even in a vacuum. No, I don't really understand it). The problem is, the energy flows orthogonal to any of the dimensions we live in (at right angles to reality, as Douglas Adams migh say). So, all we have to do is figure out some way to change the angle. Even a small amount of the tapped energy might be enough, causing I bend in space. Put the bend in the right place (say, a safe number of meters above your head), and adjust the magnitude, and you're floating.

    Unfortunately, this gravity source will not only affect you -- near as I can tell, many things in the near vicinity would be pulled straight toward you. Hope you don't have any large household appliances. Then again, this could come in handy around people you find attractive. :)

    And in case you're wondering, I got all this stuff from a book called "Tapping the Zero Point Energy" by Moray B. King....

  • gravity is so odd (Score:3)

    by Anonymous Coward on Saturday August 26, 2000 @06:17AM (#826018)
    Doesn't anyone find it odd that we don't really KNOW how gravity works ?
    I'm not really a specialist here, but it was my understanding that we don't actually have a particle to match gravity with. And thus no way to REALLY alter gravity.
    This mangetism trick is no more than it is, a trick. It's nice to see, but the gravity is still there. Now if someone would find a REAL way to alter gravity, THAT would be cool.
    Until then, space missions it is.

    The funny thing is that you can't get away from gravity, where ever you go. You feel the gravitational pull from every object from everywhere in the universe anywhere you are. Astronauts have faked zero-g because they're just falling fast enough.

    Anyway, I find it so odd that nothing explains how we can mess with gravity itself. It seems that there are a couple of things in physics that we don't quite understand correctly yet. (well, quantum mechanics ofcourse, but i doubt that will lead us to zero-g)

  • Re:Old Hat (Score:3)

    by Anonymous Coward on Saturday August 26, 2000 @05:10AM (#826019)
    Actually, there are couple of such things :)

    First, I think you meant a site about levitation [sci.kun.nl] at Nijmegen-Amsterdams University's magnet laboratory. This site has both physics and pictures :)

    Second, a Levitron [lauralee.com], which you can buy for a couple of bucks. The working principle is rather complicated, though.

    Third, Nd-Be-F supermagnets should be rather cheap nowadays, so buy and try yourself :)

    Andrei

  • Re:Practical Applications? (Score:3)

    by dattaway ( 3088 ) on Saturday August 26, 2000 @07:14AM (#826020) Homepage Journal
    oh, how about a levetating waterbed?

    An instant swimming pool without the costs or space of the structure. Just turn on a switch and the pool of water takes shape. Turn on, jump in.

    Dazzle your friends with the Levetating Electronic Bartender (tm).

    Levetating drinking glasses. No cups to wash, coasters to pick up, just levetate your Jolt Cola (tm) above your desk and guide it with the joystick toward your mouth.

    Zero gravity has got to be the ultimate environment for people who like to have fun.

  • Old Hat (Score:3)

    by ErikZ ( 55491 ) on Saturday August 26, 2000 @04:29AM (#826021)
    Making something float with magnets has been done before.

    With frogs.

    I wish I kept the link now, but it wasn't THAT interesting.

    Following the link back to the groups offical home page is intersting though. It could be just me, science though interesting experiments is always cool.

    Later
    Erik Z

  • Yay Science (Score:3)

    by Duxup ( 72775 ) on Saturday August 26, 2000 @04:30AM (#826022) Homepage
    I applaud any technology that makes it easier to get out of my chair and get my laptop, remote or whatever item I need but forget elsewhere. Yay, Case Western Reserve University!

  • acceleration without whiplash? (Score:3)

    by aozilla ( 133143 ) on Saturday August 26, 2000 @05:17AM (#826023) Homepage
    If the amount of "gravity" applied to the object could be timed to counteract the effects of accelleration of the object, we could have "acceleration without whiplash," something that certainly exists on the starship enterprise. :)

  • Researchers at bathroom.edu have done this with.. (Score:5)

    by Money__ ( 87045 ) on Saturday August 26, 2000 @04:27AM (#826024)
    A hair dryer and a ping pong ball. ;)

    "OOOoooo look, 0 G!"

  • Re:Old Hat (Score:5)

    by Suidae ( 162977 ) on Saturday August 26, 2000 @05:56AM (#826025)

    The frog, floating in a 16 Tesla field.

    http://www.sci.kun.nl/hfml/froglev.html

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