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Quantum levitation and quantum locking applications

  1. Aug 22, 2012 #1
    Hello Everyone,

    I'm brand new to the forum as a poster, although I have been quietly reading the very interesting discussions going on here for a while! I'm hoping to slowly emerge from the shadows and start posting myself. Whilst I am by no means an expert in Physics, I do love the subject and try to learn as much as I can on my own.

    (I appologize if this is not the correct place to post this thread!)

    I was recently watching a talk on TED.com about quantum locking and quantum levitation (video here: http://www.ted.com/talks/boaz_almog_levitates_a_superconductor.html ).

    The talk demonstrates quantum locking and quantum levitation, by floating a superconductor disk (0.5 microns thick and ~7.6cm in diameter) on top of a magnetic track.

    Despite the fact that the science represented was clearly not the latest, it is however supposed to inform a lot of people about the potential for this technology.

    There are a few things in the video that have been bugging me for the last couple of days. The speaker states that a 2mm thick and ~7.6cm diameter disk can support 1000kg (the weight of a small car). However in his demonstration he is able to change the orientation and direction of the disk very easily with his hand. If this is how easy it is to disturb the system, I can't help think that any amount of weight placed on the disk, whether its my toe, or a small car would send it toppling downward. We can't change Newton's Third Law after all.

    So what would it take to create a stable system, aside from keeping the material cool enough to maintain its superconducting properties? Is simply increasing the magnetic field strength to satisfty Newtons law enough to increase stability and the addition of weight to the disk? is it as simple as that with quantum locking?

    Is this demonstration pure hype? Or is there potential for this quantum locking effect to support and propel heavy loads, similar to magnetic levitation trains for example?
  2. jcsd
  3. Aug 22, 2012 #2


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    I do not know how the involved forces scale with the thickness of the magnet, but if they scale linearly, 2mm <-> 1000kg correspond to 0.5┬Ám <-> 250g or (on earth) 2.5N. It is easy to get forces of 2.5N by hand.
  4. Feb 10, 2014 #3
    Is it possible to levitate a superconductor using Earth's magnetic field?

    how come he was touching the superconductor which was at supercool temperatures with bare hands ?
  5. Feb 10, 2014 #4


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    Please don't post new questions in old threads.
    I don't think there is a superconductor light enough for that.

    You can touch very cold (or very hot) things if you do it quick enough. You can even pour liquid nitrogen over your hands, as long as the contact time is very short. The superconductor could have an isolating sheet of ice around it, so the surface is not as cold as the actual superconductor.
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