5 ms·

Hang on, wouldn't a sliver of any magnetic material behave like this within a moving magnetic field? This replication is a fail, yes?

jeron 3y ago
From the paper about the replication, they cast strong doubts on the original paper and consider it a fail
drexlspivey 3y ago
Both polarities repel the material, a normal magnetic material would attract the second time
marshray 3y ago
Neither lead nor copper are what we would normally consider a "magnetic material" like iron. That it interacts strongly with a magnetic field shows that a big change in the material, consistent with superconductivity, has occurred. Quantum level effects are newly appearing in the macroscopic world, and that's always interesting.
- Melatonic 3y ago
  Could this not also have a big use case outside of superconductivity? Decellerators or accelerators for maglev trains or similar?
  - marshray 3y ago
    Oh, definintely! Most materials are diamagnetic, but only very weakly so. I think that a new room-temperature material that was so strongly diamagnetic that it could lift the weight of its own volume in lead probably would bring some interesting new applications.
    - crooked-v 3y ago
      For example, anything with a bearing in it used in an application where it's safe to have a strong permanent magnet.
soligern 3y ago
No, it’s repelled by both poles.
nomel 3y ago
A magnetic material would orient itself to the magnet, and then move towards the magnet, not get "stuck" in its fields.
- nomel 3y ago
  Is this somehow incorrect? Getting "stuck" in a magnetic field is called "Flux pinning", which is what we're seeing here, from what I understand: https://en.wikipedia.org/wiki/Flux_pinning https://en.wikipedia.org/wiki/Flux_pinning Magnetic material can't do this. They're attracted. As some of the videos have shown, with large magnets placed next to the samples, they are not attracted.
verytrivial 3y ago
My question was on the money after all -- this appears to have been the property being exhibited. Presumably the downvoter was a co-author.

jeron 3y ago

From the paper about the replication, they cast strong doubts on the original paper and consider it a fail

drexlspivey 3y ago

Both polarities repel the material, a normal magnetic material would attract the second time

marshray 3y ago

Neither lead nor copper are what we would normally consider a "magnetic material" like iron. That it interacts strongly with a magnetic field shows that a big change in the material, consistent with superconductivity, has occurred. Quantum level effects are newly appearing in the macroscopic world, and that's always interesting.

Melatonic 3y ago
Could this not also have a big use case outside of superconductivity? Decellerators or accelerators for maglev trains or similar?
- marshray 3y ago
  Oh, definintely! Most materials are diamagnetic, but only very weakly so. I think that a new room-temperature material that was so strongly diamagnetic that it could lift the weight of its own volume in lead probably would bring some interesting new applications.
  - crooked-v 3y ago
    For example, anything with a bearing in it used in an application where it's safe to have a strong permanent magnet.

soligern 3y ago

No, it’s repelled by both poles.

nomel 3y ago

A magnetic material would orient itself to the magnet, and then move towards the magnet, not get "stuck" in its fields.

nomel 3y ago
Is this somehow incorrect? Getting "stuck" in a magnetic field is called "Flux pinning", which is what we're seeing here, from what I understand: https://en.wikipedia.org/wiki/Flux_pinning https://en.wikipedia.org/wiki/Flux_pinning Magnetic material can't do this. They're attracted. As some of the videos have shown, with large magnets placed next to the samples, they are not attracted.

verytrivial 3y ago

My question was on the money after all -- this appears to have been the property being exhibited. Presumably the downvoter was a co-author.