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Levitating a superconductor on a Mobius strip

In the video the superconductor levitates upside down, how is it possible when the gravity and acting downward and by definition superconductor repels the magnetic field.

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The point not mentioned in the video is the fact that the flux vortices from the magnets (if strong enough) can penetrate in quantum flux lines and attach inside type-2 superconductors and pin them at fixed distance from the magnets. This is called flux pinning. Pinning points are stable because of tiny impurities or defects in the crystal of the superconductor. This explains why even though the Meissner effect is always repulsive (in spite of the direction of the induced current inside the superconductor), it can still hold the SC beneath the magnet.

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  • $\begingroup$ +1 I'm out of my league on this subject , but I think the video is designed to get kids to go "wow" at physics, and the actual lectures to kids are very good. $\endgroup$ – user108787 Aug 25 '16 at 20:43
  • $\begingroup$ @Gary That's the correct answer indeed: the vortices do not repel the magnetic field, they let it penetrate inside the superconductor. The lines of magnetic flux then make a kind of cage around the superconductor, which do not care whether the superconductor is above or below the magnet. See en.wikipedia.org/wiki/Flux_pinning for instance for more details. $\endgroup$ – FraSchelle Aug 27 '16 at 9:55
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He tells you how, on the video, at 7 minutes onwards. When gravity tries to pull the superconductor downwards, the slight movement sets up electrical currents which create a magnetic field in the superconductor, allowing the neodymium magnets to "grab" onto the superconductor.

He does not mention the Meisner effect, please just watch the video again, from 7 mins onwards

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