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Superconductor news: What’s claimed, and how strong the evidence seems to be

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Re: Superconductor news: What’s claimed, and how strong the evidence seems to be

#171

Post by jeepers6 »

willis936 wrote: post #139
whatshisface wrote: post #119

Earlier quoted context omitted.

It is clearly resting on the magnet. I don't know the mechanics off the top of my head, but that is enough mechanical constraint for a pair of permanent magnets to levitate.

It isn't. Permanent magnets would be unstable. This would have to be a diamagnetic or superconducting material.

Superdiamagnetism occurs primarily in superconductors.

Reminder that flux-pinned levitation only occurs when superconductors are cooled from above to below their critical temperature while in a local magnetic field.

The researchers probably didn’t heat up their big sample above the critical temperature in air as that could have mechanically destroyed it. It was already chipped almost in two.

Re: Superconductor news: What’s claimed, and how strong the evidence seems to be

#172

Post by XorNot »

littlestymaar wrote: post #147
ortusdux wrote: post #87

Earlier quoted context omitted.

That video reminds me of the way pyrolytic graphite floats on strong magnets. https://scitoys.com/scitoys/scitoys/magnets/pyrolytic_graphi... https://youtu.be/Wk3seHNmNs8

The common point being that it levitates, at room temperature (so no cryogenic fumes on the video), but that's exactly what you'd expect from a room-temperature SC… The big difference between your graphite video and the one from yesterday is that the later doesn't move, whereas the former never rests.

The problem with the video we see is that the sample never actually levitates - one side is touching the magnet. So a regular diamagnetic material, with enough weight on one side, would display the same effect.

In this video shortly after this moment you see something very similar looking with pyrolytic carbon: https://youtu.be/VC3r9-OaWes?t=133

Re: Superconductor news: What’s claimed, and how strong the evidence seems to be

#174

Post by DarmokJalad1701 »

tux3 wrote: post #137

New scientist got a reply from the authors and a few other experts: https://www.newscientist.com/article/2384782-room-temperatur... >Kim has only co-authored one of the arXiv papers, while the other is authored by his colleagues at the Quantum Energy Research Centre in South Korea, some of whom also applied for a patent on LK-99 in August 2022. >Both papers present similar measurements, however Kim says that the seco…

Without paywall: https://archive.is/Lve8I

Re: Superconductor news: What’s claimed, and how strong the evidence seems to be

#175

Post by XorNot »

xeonmc wrote: post #120
soligern wrote: post #66

Earlier quoted context omitted.

A strange exposition video then, I would try to remove the part that wasn’t superconducting (the part touching the magnet) before I released this. A completely floating piece of this superconductor would remove literally all doubt.

You say to do WHAT to the best piece of sample they synthesized?

Scope of the claim. This is world changing. Shoot the first video, then get the dremel/pliers and cut that large bit off. It would be worth it, because if this works at all, then it's vital to prove it. We'd be having a very different discussion if that small piece was umabiguously floating and remaining locked in place.

Re: Superconductor news: What’s claimed, and how strong the evidence seems to be

#176

Post by tigershark »

carabiner wrote: post #92

Researcher on reddit thinks it's probably spurious measurement artifacts, not superconductivity: > I would say they are not faking it, but instead they just don’t understand what they are looking at. Based on what measurements they are doing, as well as how they are doing them, they do not have a good understanding of the standard processes to characterise a superconductor. Also, based on their analysis/discussion, t…

As far as I understand there is no real explanation for the measurements and the video demonstrating the Meissner effect apart from faking it. The Reddit thread that you posted alleges that they were faking the video by super-cooling a non-room temperature superconductor for example. Do you have proof that they actually are so crazy to fake a certain Nobel prize when their research can be verified in a short time? From my side I will wait a week or two for the reproduction from other labs. You can continue spreading your reddit-based opinions until then.

Re: Superconductor news: What’s claimed, and how strong the evidence seems to be

#177

Post by XorNot »

simmanian wrote: post #169

I see a few comments saying this can also be used to "solve" climate change, but I am trying to understand the how. Do people mean that the world will have less carbon footprint overall because everything will be much more efficient?

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

You build a big inductor, and because it's superconducting current just goes round and round. At room temperature you have no refrigeration losses, you can build more just as fast as you can kick out superconductor. It would be 100% efficient, have 0 self-discharge, and enormous power capacity and infinite power cycles.

Re: Superconductor news: What’s claimed, and how strong the evidence seems to be

#178

Post by NeoTar »

simmanian wrote: post #169

I see a few comments saying this can also be used to "solve" climate change, but I am trying to understand the how. Do people mean that the world will have less carbon footprint overall because everything will be much more efficient?

I think it may be that electrical power could be generated in places where (carbon free) energy production can be abundant but consumption is low (e.g. Solar power in the Sahara desert) and then transported with almost no losses to sites of high energy consumption (e.g. the cities of North Africa and Europe).

Re: Superconductor news: What’s claimed, and how strong the evidence seems to be

#179

Post by mitthrowaway2 »

jeepers6 wrote: post #171
willis936 wrote: post #139

Earlier quoted context omitted.

It isn't. Permanent magnets would be unstable. This would have to be a diamagnetic or superconducting material.

Superdiamagnetism occurs primarily in superconductors. Reminder that flux-pinned levitation only occurs when superconductors are cooled from above to below their critical temperature while in a local magnetic field. The researchers probably didn’t heat up their big sample above the critical temperature in air as that could have mechanically destroyed it. It was already chipped almost in two.

> Reminder that flux-pinned levitation only occurs when superconductors are cooled from above to below their critical temperature while in a local magnetic field.

Casual demonstrations of levitating superconductors involve first submerging the superconducting material in a (non-magnetized) tub of LN2, and then moving it onto a magnetic track. For example, https://www.youtube.com/watch?v=X5EoUD-BIss

Re: Superconductor news: What’s claimed, and how strong the evidence seems to be

#180

Post by TillE »

tigershark wrote: post #176
carabiner wrote: post #92

Researcher on reddit thinks it's probably spurious measurement artifacts, not superconductivity: > I would say they are not faking it, but instead they just don’t understand what they are looking at. Based on what measurements they are doing, as well as how they are doing them, they do not have a good understanding of the standard processes to characterise a superconductor. Also, based on their analysis/discussion, t…

As far as I understand there is no real explanation for the measurements and the video demonstrating the Meissner effect apart from faking it. The Reddit thread that you posted alleges that they were faking the video by super-cooling a non-room temperature superconductor for example. Do you have proof that they actually are so crazy to fake a certain Nobel prize when their research can be verified in a short time? Fr…

All the amateur debunking just smells like the usual confidently incorrect contrarianism, which is always popular on sites like Reddit.

There's just way too much going on for this to be a sloppy mistake. It's either real or a fraud, and in both cases the alleged errors aren't particularly important.

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