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Successful room temperature ambient-pressure magnetic levitation of LK-99

arxiv.org

11–20 of 1001 posts

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#11
post #2

Wow, is this it? Is this the confirmation?

I believe there’s no way to stably suspend an object on permanent magnetic fields, so if this is stable and doesn’t fall down then it’s hard to argue superconductivity isn’t involved.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#12
post #6

Seems to be the same one that had a video a couple of days ago https://news.ycombinator.com/item?id=36953396 Back then, many asked if this was superconduction or merely diamagnetism. Does the new paper shine any light on this question?

The exact same video URL (https://www.bilibili.com/video/BV14p4y1V7kS/) is linked to in this article. There doesn't seem to be anything new here.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#14
It’s a breath of fresh air reading about actual revolutionary science happening.

The deluge of news about non-replicable results, fabricated data, overhyped press releases from both academia and industry had become really depressing. For once after a long time it’s the real deal.

Even if this is not a RT superconductor, it’s now evident that the original authors didn’t cheat and are not crackpots as initially suspected by most.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#15
post #6

Seems to be the same one that had a video a couple of days ago https://news.ycombinator.com/item?id=36953396 Back then, many asked if this was superconduction or merely diamagnetism. Does the new paper shine any light on this question?

The paper shows a clear phase transition to diamagnetism as the material is cooled. That would be seen in superconductors and not in regular diamagnetic materials. I'm not aware of any that have that kind of phase transition. Though since we're in weird territory here, it's important to note some weird non-superconductor behavior that's beyond regular diamagnetism might be going on as an alternative explanation. But it is weird.

ETA: also, in the presence of a magnetic field, that transition temperature decreases. That's pretty huge. Unless this paper is fraudulent, I take this as the biggest positive evidence so far that something besides simple diamagnetism is going on. And, cards on table, with the assumption that the paper is not fraudulent, this pushes my odds above 50% for the first time.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#16

It’s a breath of fresh air reading about actual revolutionary science happening. The deluge of news about non-replicable results, fabricated data, overhyped press releases from both academia and industry had become really depressing. For once after a long time it’s the real deal. Even if this is not a RT superconductor, it’s now evident that the original authors didn’t cheat and are not crackpots as initially suspect…

Agreed. It's felt like so many of the technological marvels have either happened quietly (e.g. the reductions in chip size) or in the past (e.g. all the physics breakthroughs of the 1900s). Like ChatGPT, this seems to have the characteristics of being both accessible and completely novel.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#17
post #11
post #2

Wow, is this it? Is this the confirmation?

I believe there’s no way to stably suspend an object on permanent magnetic fields, so if this is stable and doesn’t fall down then it’s hard to argue superconductivity isn’t involved.

[dead]

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#18

It’s a breath of fresh air reading about actual revolutionary science happening. The deluge of news about non-replicable results, fabricated data, overhyped press releases from both academia and industry had become really depressing. For once after a long time it’s the real deal. Even if this is not a RT superconductor, it’s now evident that the original authors didn’t cheat and are not crackpots as initially suspect…

Agreed. It's felt like so many of the technological marvels have either happened quietly (e.g. the reductions in chip size) or in the past (e.g. all the physics breakthroughs of the 1900s). Like ChatGPT, this seems to have the characteristics of being both accessible and completely novel.

I feel like the host of “in 30 years we would have X” made 40 years ago are suddenly manifesting.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#19
post #11
post #2

Wow, is this it? Is this the confirmation?

I believe there’s no way to stably suspend an object on permanent magnetic fields, so if this is stable and doesn’t fall down then it’s hard to argue superconductivity isn’t involved.

https://en.wikipedia.org/wiki/Diamagnetism

https://en.wikipedia.org/wiki/Earnshaw%27s_theorem

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#20
post #6

Seems to be the same one that had a video a couple of days ago https://news.ycombinator.com/item?id=36953396 Back then, many asked if this was superconduction or merely diamagnetism. Does the new paper shine any light on this question?

Yes, in two forms:

First it shows a temperature graph vs moment, as they heat it it loses the diamagnetism around the temperature LK99 is said to be superconducting.

Second only a superconductor will have net-zero field, which means "stable" levitation. In the video they approach the sample with the magnet and flip it while the piece is mostly "in place". A regular diamagnet generates a external field that "follows" the field applied so it would likely move sideways, that is why to "levitate in place" a diamagnet people normally use a Halbach array.

EDIT: A Halback array is made alternating the poles N-S of the magnet, so that forces of repulsion created by the diamagnet cancel. This is why you will see people using multiple magnets when levitating pyrolytic graphite.

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