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Transportation Science

Researchers Demonstrate Quantum Levitation 133

UnknownSoldier writes "Wired reports that researchers at Tel Aviv University have discovered you can 'lock' a magnetic field into place with a superconductor. They have a very cool demonstration of a frozen puck and some of the neat things you can do with it while its orientation remains locked but its location is movable. Might we someday see high speed trains that will be 'impossible' to tip over, or a new generation of batteries with this technology?"

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Researchers Demonstrate Quantum Levitation

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  • Hoverboard (Score:3, Insightful)

    by The Joe Kewl ( 532609 ) on Wednesday October 19, 2011 @02:07PM (#37765530)

    Awesome!
    WHEN Can I order my Hoverboard?!?!?!

    • by Wonko the Sane ( 25252 ) * on Wednesday October 19, 2011 @02:10PM (#37765556) Journal

      Looks like a case of cold feet.

      • by jhoegl ( 638955 )
        Although the logistical problems ran through my mind on how one can implement this real world, it is still freakin cool!
        • Although the logistical problems ran through my mind on how one can implement this real world, it is still freakin cool!

          Yeah, real cool. Liquid Nitrogen cool.

    • Agreed, though it seems like this thing is a little too easy to "unlock". How would you build a train when a small nudge can make it change alignment?

      • by hawguy ( 1600213 )

        Agreed, though it seems like this thing is a little too easy to "unlock". How would you build a train when a small nudge can make it change alignment?

        It's not clear how much force he was using to change the orientation of the puck, but since the puck can support itself while upside down, its appears to exert at least as much force as it takes to support the weight of the puck. So a 100 ton train may require 100 tons of force to lift it from the track.

        From the demo, it's hard to see if it would have enough force to keep the train on the track, or if the pucks would have to surround the track to keep the train centered -- like conventional maglev trains. (

      • Well flicking your finger will deal enough force to unlock anything in that scale from that demonstration, By the same logic real trains are subject do danger of a medium sized bird lifting them off of the tracks. The question isn't how easy is it to change the alignment on a air hockey puck sized object. The question is how it will scale when you are working with a multi ton train.
        • Along those lines, how many tons of superconductor does it take to support a many ton train.

          • by Yvan256 ( 722131 )

            42.

          • by mikael ( 484 )

            We did have MagLev trains [wikipedia.org] - not super-conductors, but just ordinary copper coils.

            Some airports (like Birmingham, UK) did have them but stopped using them due to to the rising cost of electricity and maintenance.

    • saying that you can not sue if you get hurt.

    • not till 2015
      Wait... that was the shoes
    • You can have your hoverboard right after they start making pavements out of rare earth magnets.

  • by Anonymous Coward

    This isn't new is it? It's a very cool demonstration, but unless I'm mistaken they didn't discover this--the actual article doesn't say it was a new discovery and I'm fairly sure my physics teacher showed me this a year or two ago. It is really cool, and the physics behind how it works is very interesting. It's pretty accessible too, don't be discouraged from reading up on it because you think it will be too hard to understand.

    • Re: (Score:2, Informative)

      by Carnildo ( 712617 )

      Looks to me like a demonstration of the Meissner effect [wikipedia.org], something that was discovered in 1933.

      • It isn't. Old Tech with a new name and twist. This all has to do not necessarily with the quantum properties, but more to do with matter being super cooled [topdocumentaryfilms.com]. For some reason matter behaves differently as it approaches absolute zero. This is similiar to the Bose-Einstein condensate [wikipedia.org] and the Meissner effect as linked above.

        although it is practical in the lab and in theory, there are still problems that occur when scaling it up. Like how to keep the track cooled for example. Its still a ways off.

        • by 7-Vodka ( 195504 )
          So WHY has nobody yet made a room with a cooled superconducting floor and went in wearing magnetic boots? WHY?
          • by Khyber ( 864651 )

            Well, unless I'm mistaken, *YOU* need to be wearing the cooled superconductor, for one.

      • by JoshuaZ ( 1134087 ) on Wednesday October 19, 2011 @03:33PM (#37766766) Homepage
        This is not the Meissner effect! If it were you wouldn't be able to do the stunt where they move the disk to a different angle and it stays there. This is more subtle. The Meissner effect involves superconductors not letting magnetic field lines pass through the superconductor. This involves special superconductors that allow magnetic field lines to pass through but make the field lines get trapped in imperfections in the superconductor. The name of this effect is "flux pinning" http://en.wikipedia.org/wiki/Flux_pinning [wikipedia.org]. Here is the website of the group who made this video where they explain it http://www.quantumlevitation.com/levitation/Quantum_Levitation.html [quantumlevitation.com]
        • It's an application of the Meissner effect, just ensuring the superconductor is thin enough that penetrable locations exist.

        • by Anonymous Coward

          I got the impression from those links that the new piece of this is that the superconductor is only 1 micron thick, which allows the magnetic field to penetrate it in "quantum tubes," which makes the orientation locking possible. The link to the train below (http://www.youtube.com/watch?v=TeS_U9qFg7Y&feature=player_embedded) shows the train shaking as it takes corners. Can anyone else claiming that this is old technology confirm that the superconductors in the other experiments they have used were much

      • by Anonymous Coward

        The Meissner effect is just the expulsion of magnetic fields when gaining diamagnetic properties during transition to superconducting state, IIRC. That just makes the superconductor repel magnets. The "quantum locking" effect the guy is talking about -- what keeps the puck suspended and prevents it from flying away from the magnet -- has a different name, flux pinning [wikipedia.org] and only occurs in Type II superconductors.

        No, this isn't new at all. Though perhaps the compound they are using may be... unless they j

    • Not exactly new, but it is an application of the physics behind the Meissner effect. Something that aside from floating a cube above a dish of liquid nitrogen I've not really heard of anyone bothering with, or at least demonstrating in such a jaw dropping manner.
      • by flosofl ( 626809 )
        It's not the Meissner effect. That is for Type I superconductors. This is Flux Pinning and is a different effect for Type II superconductors. You can't change orientation and "lock" it (the Pinning part of the phenomenon) with the Meissner effect. There are some very informative links above regarding this.
        • As I understand it it is a specialization of the Meissner effect wherein by introduction of defects magnetic fields may penetrate the superconductor but only at these defect points. These magnetic fields able to penetrate act as control rods of a sort which provides the "stiffness." BTW: you wouldn't happen to mind providing said links would you?
    • Read the comments in the linked Wired article. You're right. Not technology/discovery, but just a new application of existing knowledge.
    • by tmosley ( 996283 )
      Yeah, we made these in physical chemistry lab 7 years ago. Not really a big deal.
  • by Anonymous Coward

    When has train tipping been a major problem? All those pesky teenagers I tell you - bored and at it again!

    • by vlm ( 69642 )

      When has train tipping been a major problem?

      Well, all the time. Clay/sandy soil and washouts due to spring thaws, extremely severe thunderstorms where you get 3 inches of rain per hour, hurricanes... Even just plain old poor maintenance.

      • So how is flux pinning going to stop the train from tipping over if the base that holds the magnets tips over due to the soil supporting it becoming unstable?

        • With the older demos, the train would tip over if the track tipped. In fact, it stayed in exactly the same orientation to the track no matter what, so if you flipped the track upside-down the train would be hovering upside-down too. That's not exactly ideal.

          This demo, OTOH, showed that they could set any orientation they wanted between the puck and the track it rode on, and change it at will. Maybe your track has slanted sideways and you don't want the train tilting at that angle?

          Now if they can come up wit

        • Clearly you support the magnets with magnets below. Then when the soil gives out it'll float in place. For extra security, secure the second layer with a third layer of magnets.

          Turtles, turtles all way down!
          • As I read the first line of your comment, I thought to myself, "I'm going to post a reply saying, 'But it's turtles all the way down.'".

            Then I read the second line of your post and saw that the reason I thought of turtles is because that's exactly where you were going.

            In any case, I laughed.

  • SUPERCONDUCTOR (Score:5, Informative)

    by gygy ( 1182865 ) on Wednesday October 19, 2011 @02:12PM (#37765578)
    SUPERCONDUCTOR not semiconductor !
    • Seriously. Meissner effect is old news, too. I mentioned to a friend how slashdot seemed to have gotten really dumbed down in the last year, and he made an interesting connection: ipads became popular.
      • Is Slashdot.org a default bookmark on iPads? That would make the dumbing down make much more sense.

      • Re: (Score:3, Informative)

        by Tinctorius ( 1529849 )
        This is flux pinning, and apparently, is a different phenomenon than the Meissner effect.
        • by robotkid ( 681905 ) <[alanc2052] [at] [yahoo.com]> on Wednesday October 19, 2011 @03:13PM (#37766500)

          This is flux pinning, and apparently, is a different phenomenon than the Meissner effect.

          Yes, but this was already well known in the late 1980's when type II superconductors hit center stage in the solid-state physics world. And 30 seconds later every single person in the field thought "hey, we could SOOO build a sweet maglev train with this". But it's still not practical by any stretch of the imagination except as a neat toy.

          So /. is only 20+ years late instead of ~80 years with the Meissner effect.

    • by tmosley ( 996283 )
      Yeah, a semiconductor is what you get when Gustav Mahler sleeps on the train tracks.
  • Where can I buy this desk toy set?

  • by genjix ( 959457 ) on Wednesday October 19, 2011 @02:14PM (#37765612)

    This has been around since the time of Carl Sagan. For a much better explanation of what is happening (and the science behind it), see this video:

    http://www.youtube.com/watch?v=TeS_U9qFg7Y&feature=player_embedded [youtube.com]

    They haven't invented anything new so don't get excited about wipeout ships and hoverboards just yet. The problem is the immense amount of energy to keep the superconductor cooled.

    • Did they have superconductors that worked at liquid nitrogen temperatures in 1980? The amount of energy needed to keep nitrogen liquid is significantly less than what it takes to keep helium liquid.

    • I think the difference between the new video and the one you posted is that in the new video, the superconductor can be placed in any position and it will stay in that orientation, and can have its orientation changed manually at any time. Your video, I think they imply that the positioning is locked in during the cooling process, and cannot be changed until it warms and is cooled again. So, this aspect of the material seems new.
    • Look at 0:53 and 1:50 in the video you posted -- this train is locked in position in *one orientation* at *one distance* from the track, and it happens when you cool the superconductor down. The video in the original post shows you can set the orientation and distance by applying greater than some threshold force, and then it is preserved. Orientation preservation is remarkable.
  • by poity ( 465672 ) on Wednesday October 19, 2011 @02:16PM (#37765638)

    of calling a superconductor a semiconductor?
    WIRED, where do you get your reporters?
    And /., where are you editors?

    • That's was my fault, not Wired's, for mixing up superconductor and semiconductor. That's what you get when you rush a submission when you first wake up :/

      Sorry.

  • Firstly it's a superconductor, not a semiconductor (as would have been obvious had the editor even bothered to glance at TFA). They're totally different things. Also, this is not news at all: it's a cool video, but again as TFA states it's just an example of the well-known Meissner effect.
  • by Dr Bip ( 601304 )
    The simple error in the original post is trivial - it's a superconductor. And it demonstrates flux pinning. But this has been demonstrated ever since superconductors have been made with non-superconducting regions in them (ie, not elemental superconductors like Pb and Al). This is *not* news. Unless it is the mid 1980s and I've not noticed.
  • that I can say someone showed me something that makes my jaw drop. But this most certainly did. Wow, this absolutely floored me. Good work guys.
    • I agree! Daamn that's cool!

    • Well until we can come out with superconductors that can operate at room temperature, don't expect to see this applied anywhere else aside from the lab.
      As others have pointed out, this is not new and has been around for over 20 years, the fact that it requires extremely cold temperatures has relegated it to a mere novelty as far as practical applications go.

    • Hmmm...you realize that what may be a rare event to you is ho-hum reality for the rest of us, right? Demonstrations of the Meissner Effect (or more specifically, flux pinning) stopped making jaws drop during the Reagan administration, dude. This is circus science -- all spectacle, no substance.

  • by cosm ( 1072588 )
    All technical typos and misleading whatever aside, and aside from all the hawking about how this has already existed or this is not new blah blah blah....THIS SHIT IS STILL FUCKING AMAZING. GET OVER YOURSELVES.
    • by Carnildo ( 712617 ) on Wednesday October 19, 2011 @02:32PM (#37765864) Homepage Journal

      The problem is not that this isn't amazing, it's that the Slashdot editors (and Wired) are presenting an 80-year-old discovery as something new -- and then describing it using the wrong terminology.

      • by cosm ( 1072588 )
        Very true, perhaps it's time for me to start weening off /., it gets tiring seeing so many cynical comments about the editing and misuse of terminology, and naturally those are not the fault of the commenters. Albeit /. does beat most all other news sites and the likes of Youtube in regards to the level of intelligence in its comment sections.

        I guess I just can't tell if the rising cynicism here matches the degrading quality of editing.
        • by radtea ( 464814 ) on Wednesday October 19, 2011 @02:52PM (#37766174)

          I guess I just can't tell if the rising cynicism here matches the degrading quality of editing.

          They go hand in hand, in part because of the number of ignorant people responding to this story saying "WOW THAT IS SO AMAZING!", which just announces that they have somehow managed to preserve their ignorance of this effect for long enough to be old enough to post on /. but are still posting on /. It makes those of us who have an actual interest in science and technology feel like this isn't really the place we should be.

          As well as presenting an 80-year-old effect that has been a stock benchtop demonstration for 20 years as something "new" and "exciting", the marketers (not scientists or engineers) behind this have added the word "quantum" to it, which is so obviously catering to the ignorant it is just sad. I've even seen this described as using "quantum superconductors", which nicely distinguishes them from all the classical superconductors out there...

          • So where can a person go for real information and/or actual thinking on any topic? Even the best posters on /. appear to me to be mostly posturing, with nobody actually learning anything from the discussion.

            • by radtea ( 464814 )

              So where can a person go for real information and/or actual thinking on any topic?

              I've been casting around for a while on this question and nothing jumps out. arstechnica is kind of ok, but often gets facts completely wrong and their editorial "explanations" frequently read as if they are written by someone who either lacks understanding of the subject or the audience--they often confuse me, and I'm a physicist with eclectic research experience. Bad Astronomy is also OK.

              The basic problem, I think, is that the number of technically knowledgeable people on the Web stays roughly constant

              • The basic problem, I think, is that the number of technically knowledgeable people on the Web stays roughly constant (the number of STEM grads in the US has been flat for 25 years, for example) but the total number of people is still increasing.

                I think its probably worse than constant for English language sites, because a large percentage of those people prefer Chinese sites and/or do not have interests outside their own research area.

          • Maybe it's just me, but I think you read the summary wrong. Sure, levitation, quantum levitation, whatever. If it gets someone with a passing interest in science to check it out and say, "Hey, that's cool!", isn't that a good thing? The point is, it doesn't say that it's brand new. Maybe they could have mentioned that it builds upon 80 year old observations, but the part that is new is that they've discovered either how to, or that they can, lock the orientation of the superconductor.
          • by Sabriel ( 134364 )

            So, eighty years ago, we knew about using imperfections in superconductors to pin them within a magnetic field as opposed to simply floating them above it?

    • All technical typos and misleading whatever aside, and aside from all the hawking about how this has already existed or this is not new blah blah blah....THIS SHIT IS STILL FUCKING AMAZING. GET OVER YOURSELVES.

      YEAH! What he said!!!

  • Why the "quantum"???? can anybody explain?
    • Re:Why?! (Score:4, Informative)

      by Carnildo ( 712617 ) on Wednesday October 19, 2011 @02:40PM (#37765992) Homepage Journal

      Using "quantum" in the description makes it sound like a cool new discovery, rather than simply a demonstration of magnetic levitation [wikipedia.org] using the Meissner effect [wikipedia.org] and flux pinning [wikipedia.org].

      • Using "quantum" in the description makes it sound like a cool new discovery

        I don't get this about people. Quantum mechanics was worked out at around the same time we were figuring out airplanes. I don't see people stopping dead in their tracks and staring slack-jawed into the sky whenever a jet flies overhead. But you can always baffle people by throwing a "quantum" in there.

        Quantum means "comes in little chunks." OH MY GOD, THE WORLD COMES IN LITTLE CHUNKS?! THAT'S UTTERLY UNBELIEVABLE."

        You guys need a b

        • by Fauxbo ( 1393095 )

          Much like Jets, Quantum Mechanics are very interesting when up close and personal.

          Seeing a Jet fly by 100 feet above your head will make me star slack-jawed into the sky, and think man that is big and flying... weird.

          I do have a full understanding of the science behind flight and some of the science behind Quantum Mechanics (saying a full understanding would be lying, it's still freaky to think about)

          Seeing this up close and personal is neat, that's all.

        • "I think I can safely say that nobody understands quantum mechanics." - Richard Feynman

          There lies the difference. No reputable scientist would have said that about aircraft anytime in the last 75 years.

  • Better video. (Score:5, Informative)

    by Ecuador ( 740021 ) on Wednesday October 19, 2011 @02:26PM (#37765758) Homepage

    Try this longer video instead. [youtube.com] It has construction details, explanations, double levitation etc.

    Also, "semiconductor"? Jeez, that is a lame mistake even by Slashdot standards!

  • this has been demonstrated before. now, would the entire track with puck locked in flux in a track weigh the same as the sum of the entire track + the puck not locked in flux in a track? if no, THAT would be news.
  • by Dunbal ( 464142 ) * on Wednesday October 19, 2011 @02:28PM (#37765796)

    Might someday we see high speed trains that will be 'impossible' to tip over

    Yeah, because tipping over is the major concern with high speed trains. Who writes this stuff?

    • Not CmdrTaco. Just sayin'.

    • Might someday we see high speed trains that will be 'impossible' to tip over

      Yeah, because tipping over is the major concern with high speed trains. Who writes this stuff?

      Any train using a metal rail system regardless of speed, can derail and tip, because once derailed there is no force to elevate the carriage itself. It's not especially hard to damage a track to that point either. And think of earthquake zones where a majority of high speed trains are used. Think of losing speed while on a banked incline. Meanwhile parking a magnet powerful enough to fatally shove a 200 ton locomotive off a bridge would probably be noticed driving around...

      I suspect it is far more viable an

  • I love living in the future.

  • When this video first made the rounds on Fark and elsewhere [lawrenceperson.com].

    By the way, here's a longer video with more explanation of how it works. [lawrenceperson.com]

  • This is the first bit of science I've seen that could plausibly be turned into one of the staples of SciFi, the tractor beam. How long before they have one that can move the (levitating) puck at a distance?
  • Superconductors have been there for ages. I remember being shown levitation like this in high school. The article doesn't seem to mention the actual discovery.

  • We did essentially this in my high school physics class in 1987.

    • Excatly! Even the superconductor itself is YBCuO, which has been well known since 1986. It's the first "Type 2" superconductor to have been discovered. Back then things were going so fast that many people thought a room-temperature superconductor was going to be discovered within a reasonable amount of time. So it is indeed sad that 25 years later, we've basically made no real progress.
      • Excatly! Even the superconductor itself is YBCuO, which has been well known since 1986. It's the first "Type 2" superconductor to have been discovered.

        It may be the first high-temperature superconductor discovered. Type II superconductors go back to the 1930s. (I worked with Nb3Sn samples when I had a summer job at Gulf General Atomic in 1969.)

  • Nice piece of non-physically driven motion (after initial nudge). No physical wear if the pieces don't touch each other.

    If that puck were in a complete vacuum in a supercooled chamber I wonder how long that puck would rotate?

    • I was thinking this might make a pretty cool magnetic bearing, if the cooling could be sorted - flywheel energy storage springs to mind.
  • There are a ton of posts going on about how it's just the "Meissner effect", the researchers aren't claiming that is something new, they are claiming they have built the first track that uses the Meissner effect for levitation and can lock the magnetic field to angle the object.

    "Researchers at the school of physics and astronomy at Tel Aviv University have created a track around which a superconductor can float, thanks to the phenomenon of “quantum levitation“.

    This levitation effect is explained

  • One step closer to being able to play WipeOut! for reals... http://www.youtube.com/watch?v=iHlHitIc7pY [youtube.com]
  • by Skylax ( 1129403 ) on Wednesday October 19, 2011 @03:54PM (#37767036)
    every physics student gets a demonstration of this effect in his solid state physics lecture. But usually the superconductor is rather small and is put into a small matchbox type car to drive it around a track. Here they used a relatively large and bulky superconducting disk, so the orientation locking is more visible. Although not new, it never gets old and I'm always fascinated by it. Just don't use the word "discovery" here!
    • Hey, there's another thread today that claims non-Newtonian fluids have just been discovered...

      rj

    • by Anonymous Coward

      Maybe it was a discovery for that researcher the same way America was a discovery for European people. Congratulation you discovered something many people already knew about.

  • That he's handling that superchilled hockeypuck so easily. You'd think a superconductor would suck all the heat out of your fingertips while at the same time becoming too hot to remain a superconductor.

    I've known about that effect for ages but I haven't ever seen a live video of it, so I still find it to be reasonably nifty. I'll be much more impressed when you can do it with a room temperature hockey puck, though.

  • by strack ( 1051390 )
    now a room temprature superconductor. *that* would be news.
  • This effect is well known and has been since somebody named Meissner wrote a paper about it in 1933. In 1986, I attended a public lecture at Caltech by Richard Feynman on the "Meissner Effect," which was accompanied by a video starring (surprise) a frozen hockey puck. It was mildly interesting at the time, but that was a quarter century ago -- to see the same effect treated like it is something strange and new is just sad. Science should be about discovery, not showmanship. Looking at you Sagan, Feynman

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