Quantum levitation (locking) 3mm thick disk could carry 1000kg small car claim I watched this TED presentation: http://www.ted.com/talks/boaz_almog_levitates_a_superconductor.html
It is about superconductivity and quantum levitation. It tells that super-thin, three-inch disk can levitate something 70,000 times its own weight.
In exact terms, presentation @9:40 says: 3mm thick disk could carry 1000kg small car.
And author says "I can hold small car in my hand".
Is he implying that if holds superconducting wafer with a car locked in using Meissner effect he will not feel weight of a car on his hand?
 A: Sadly the Meissner effect can't be used as an anti-gravity device. If you lay under the magnet and put the 3mm superconducting disk and car on top you would indeed be squished.
The presenter does use the words "in my hand", but I suspect this is just poor phrasing and I'm sure he is not suggesting he could lift a car in one hand using a superconducting disk. What he means is simply that the repulsion between the magnet and the superconducting disk is so strong that you would need to press with a force of 1000kg to push the disk into contact with the magnet. That force is of course transmitted to whatever is underneath the magnet e.g. a squished physicist.
A: The Title of the video is misleading. What Boaz Almog is demonstrating is not at all levitation. The disk is not pushed away from the magnet, and it does not levitate. It is fixed or trapped in the magnetic field, by an effect refered to as "Quantum Locking" or "Flux Pinning". This can be demonstrated by locking the disk in space underneath the magnet, which works just as well. If the magnet was pushing, – and so 'levitating' – the disk, it would be a force acting upon the disk to neutralize the gravitational pull from earth, and it would not be possible to fix the disk under the magnet (it would fall down to earth).
The disc is essentially a very thin superconductor. Superconductors will expel magnetic fields from within, but in this case, where the superconductor is so thin, millions (or billions) of single magnetic strands penetrates the disk, allowing for the disk to be locked in place at various distances and angles from the magnet.
The disk is able to carry the cooling material put on top of it (and can carry 70.000 times it's own weight), but to scale the disk up wouldn't simply be a matter of making it thicker (I believe the magnetic strands would no longer penetrate the superconductor). Maybe this can be achieved by layering many super thin discs?
Anyway, say that the experiment could be scaled up, to carry a car, then no, the person underneath would not be crushed – no more than you're crushed by a bridge, walking under it, as it's fixed in place. And you wouldn't really "lift the car" with the hand - no more than you're lifting a bridge, by placing you hand under it pressing up. You can't lift it, and if the experiment had been scaled up to this level, you would also not be able to displace the locked super conductor (with or without a car on it) with the strength of your arm.
This video visualizes this pretty well:
http://www.youtube.com/watch?v=Ws6AAhTw7RA
If the superconducter is not so thin, you get another effect, where the superconducter can be 'trapped' at a fixed distance to the magnet, as seen here:
http://www.youtube.com/watch?v=Z4XEQVnIFmQ
A: I highly doubt, that a superconductor can support 70,000 times its own weight.
In fact, the force generated to "levitate" the disc is equal to the weight of the superconductor.
These properties are attributed to a magnet, which a superconductor is not.
