Quantum Levitation

My sister won the science fair with a “frictionless puck” using CO2, two jars, and two hockey pucks. This is not that:

More here.


  1. #1 MadScientist
    October 18, 2011

    Wow … I wish I had a superconducting puck that size.

    [OT] FSF is looking for signatures on a petition to keep future PCs with UEFI Secure Boot capable of booting other systems:


  2. #2 Joshua Zelinsky
    October 18, 2011

    Apparently this isn’t the Meissner effect but something more subtle involving magnetic field lines getting “caught” in the superconductor. I don’t really understand what this means. The physics seems more complicated than the usual Meissner effect. Sure is cool though.

  3. #3 Greg Laden
    October 18, 2011

    I checked with Jim Kakalios on this just now (we were at an event) and this is a quantum phenomenon, according to him. Personally, I’m still thinking its fake, but what do I know?

  4. #4 Chris P
    October 19, 2011

    Good, quick explanation of what’s going on here: http://jtotheizzoe.tumblr.com/post/11590151866/if-this-video-doesnt-make-your-jaw-drop-you

    Flux tubes!

  5. #5 Mu
    October 19, 2011

    The most amazing part:

    Quantum Levitation

    Posted on: October 20, 2011 10:05 AM, by Greg Laden

    and we’re commenting on the 19th. Take that, Einstein.

  6. #6 Greg Laden
    October 19, 2011

    Mu: Yeah, that’s because, just for fun, I wrote this post using those new extra-fast neutrinos.

  7. #7 rob
    October 19, 2011

    i first saw this at a colloquium in the late 80’s when high Tc superconductors were first discovered. pretty cool. (ha!)

    it’s been over 20 years, and there still is no good theory about how high Tc superconductors work. then again, it took over 40 years before BCS theory described ordinary superconductivity.

    i still want a jetpack.

  8. #9 Knightly
    October 19, 2011

    Even if it’s fake, the technology they’re using to fake it seems pretty amazing itself.

    I’ve heard some controversy over whether or not it’s actually “quantum,” but that’s kind of an afterthought as far as I’m concerned. If it works and it’s replicable, they can call it what they please, so long as I get my freaking hover car.

  9. #10 glen
    October 19, 2011

    The superconductor seems to stay superconducting for longer than I would expect. Anyone have info on the type or whether there are any other tricks to how they have kept it cool?

  10. #11 Mac
    October 21, 2011

    @ glen (#10)

    To get the ‘locking’ effect they use a superconductor that is only 1 micron thick.

    That means that most of the ‘puck’ can simply be thermal insulation – so even though most of the outer part of the puck will be approaching room temperature – but the inner section of 1 micron can still be nice and chilly.

    That’s my guess anyway.


  11. #12 rob
    October 21, 2011

    at Mac #11: the “locking” effect if magnetic flux tubes getting pinned by defects in the crystal. when the superconductor superconducts, external magnetic fields are expelled. mostly. some get pinned, and cause the leveitation effect. this effect can happen with thicker crystals too. the first one i saw in the 80’s was about 3/4″ diameter and 1/4″ thick. it could levitate and hang upside down from the pinned flux.