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LK-99 isn’t a superconductor

nature.com

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Re: LK-99 isn’t a superconductor

#701

Post by mike_d »

imiric wrote: post #448
jschveibinz wrote: post #266

Earlier quoted context omitted.

On the bright side: when people say “believe in the science,” this is exactly what they should be thinking: challenge. This whole process has been super healthy and similar challenges are important and needed for everything published, not just this particular research area. I might be out in left field, but I read so often that researchers are running out of ideas. What’s wrong with getting a PhD for challenging some…

> This whole process has been super healthy Has it, though? The South Korean paper claimed to have found "The First Room-Temperature Ambient-Pressure Superconductor". It took a month for researchers around the world to essentially debunk this. Science works by peer review, yes, but that should have never been a claim to begin with. They were blinded by excitement of the results and eager to publish the paper, instead…

> The South Korean paper claimed

As I understand it the paper was a leaked preprint. Which means they didn't "claim" anything, but were distributing it to get peer review and feedback before publishing.

Re: LK-99 isn’t a superconductor

#702

Post by barbegal »

So I can understand how having a phase change causes the material to have a critical temperature but why does it also have a critical current and a critical magnetic field. A simple phase change material wouldn't have a variable critical temperature dependent on current?

Re: LK-99 isn’t a superconductor

#703

Post by breuleux »

usrbinbash wrote: post #421
breuleux wrote: post #127

Earlier quoted context omitted.

> Imagine a power-grid that no longer loses power to electrical resistence in the wires. From what I can see the power loss is in the 8-15% range. It'd be awesome to save that, but it's not game changing, and you have to take into account the cost of replacing the wires.

> It'd be awesome to save that, but it's not game changing An 8-15% increase in available electricity without any new power plants built isn't game changing? The ability to transport power over longer distances, making eg. solar farms in remote locations suddenly feasible projects isn't game changing? > and you have to take into account the cost of replacing the wires No I really don't have to, as we, as a species, s…

> The ability to suddenly boost the efficiency of our electrical grids by 8-15% would not solely solve the problems our species currently causes for itself, but it would help a ton.

That's far from clear. If our grids are 8-15% more efficient and the cost of electricity falls accordingly, it will boost demand and we may end up needing more power plants than we otherwise would have. If the goal is to reduce the consumption of a resource, making its consumption more efficient is often counterproductive (see [1,2,3]). Granted, if the alternative is burning fossil fuel then it's a good thing! But once electricity becomes more economical than fossil fuels for all uses, making it even cheaper is not going to help the biosphere. And I think that's probably going to happen before we have a room temperature superconductor that can be used in power transmission.

[1] https://en.wikipedia.org/wiki/Jevons_paradox

[2] https://en.wikipedia.org/wiki/Khazzoom%E2%80%93Brookes_postu...

[3] https://en.wikipedia.org/wiki/Rebound_effect_(conservation)

Re: LK-99 isn’t a superconductor

#704

Post by sigmoid10 »

pininja wrote: post #694
sorenjan wrote: post #237

Sixty Symbols released a video about this yesterday, and in it professor Philip Moriarty is less than impressed with the whole ordeal. I haven't been paying attention, I'm too jaded and skeptical and assumed from the start that there was something wrong and much hype about nothing. Bad Science and Room Temperature Superconductors - Sixty Symbols: https://www.youtube.com/watch?v=zl-AgmoZ5mo

As Philip points out, Sabine Hossenfelder’s quick summary on LK-99 2 weeks ago punched large holes into this whole thing in less than 5 minutes. I wish media outlets presented skeptic viewpoints instead of just hype.. but that doesn’t sell. LK99 - A new room temperature superconductor? https://youtu.be/RjzL9cS3VW8

Hossenfelder is just a cynic that critizises more or less everything that isn't her own work. She even tried to discredit LIGO a few years ago - not even using her own insight but merely by paraphrasing what a Danish group thought they had seen as error. This issue has been resolved since then and the Danes just misunderstood parts of the original paper.

Re: LK-99 isn’t a superconductor

#705

Post by selimthegrim »

jimmySixDOF wrote: post #208
vecter wrote: post #14

In their preprint, the Korean authors note one particular temperature at which LK-99’s showed a tenfold drop in resistivity, from about 0.02 ohms per centimetre to 0.002 ohms per cm. “They were very precise about it. 104.8ºC,” says Prashant Jain, a chemist at the University of Illinois Urbana–Champaign. “I was like, wait a minute, I know this temperature.” The reaction that synthesizes LK-99 uses an unbalanced recipe…

Iris, the fabled ethnicly Russian LK99 Homebrewer with the Catgirl Girlfriend, is not convinced : - "70% CuS impurity" are you sure you didn't grab the Chalcocite by accident? - There's no significant CuS in samples prepared at 925°C. There cannot be. - I tried forcefully introducing sulfide into pbo, it just. Doesn't work. Even at 600°C. PbS reduces lead in 2 PbO to 3Pb, leaving as SO2. https://twitter.com/iris_IGB/…

"ethnically Soviet" she insisted IIRC

Re: LK-99 isn’t a superconductor

#706

Post by aslfjiasf »

onion2k wrote: post #607
vietvu wrote: post #542

Earlier quoted context omitted.

When I told my wife about this, all she replied was how it's gonna be monopolized by big countries/big tech and our third world country like ours will never use it. It's a point, but well human need to push the limit, no matter what.

When I told my wife about this, all she replied was how it's gonna be monopolized by big countries/big tech and our third world country like ours will never use it. The materials and hardware required to make LK-99 are within the reach of a high school. It's really simple and doesn't require anything more than a very hot oven (hotter than a domestic one, but still very common). If it'd turned out to be a real superco…

I'm not sure about that. So many people had hard time synthesizing LK-99, and the original researchers said that even for themselves only 1 out of 10 attempts to create a material succeeded.

The pure LK-99 crystals pictured in the article were obtained using more advanced technique: "Unlike previous synthesis attempts that relied on crucibles, the researchers used a technique called floating zone crystal growth that allowed them to avoid introducing sulfur into the reaction, eliminating the Cu2S impurities."

But I agree that if there's money to be made, it will be available world wide quickly.

Re: LK-99 isn’t a superconductor

#707

Post by Galacta7 »

SilasX wrote: post #116
earthboundkid wrote: post #60

Earlier quoted context omitted.

The real superconductors were the friends we made along the way.

"Don't you guys get it? We did find a room-temperature superconductor! It was us -- conducting teamwork , with no resistance." Sitcom's live studio audience: "Awwwwwww!"

(Or more likely) Live audience: "Ohmmmmmm!"

Re: LK-99 isn’t a superconductor

#708

Post by jboy55 »

EthanHeilman wrote: post #697
jboy55 wrote: post #696

Earlier quoted context omitted.

I felt a similar way with the news of the fusion 'breakthrough' around 6 months ago. "Fusion power is here! All we need to do is engineering!". They achieved this fusion by creating a container of material that produced massive amounts of xrays when it was bombarded by a high powered laser. These xrays caused another container's surface to ablate at such a rate it compressed its interior to the point that fusion was…

> They achieved this fusion by creating a container of material that produced massive amounts of xrays when it was bombarded by a high powered laser. These xrays caused another container's surface to ablate at such a rate it compressed its interior to the point that fusion was achieved. You are telling me that a US weapons lab just announced a successful path to a laser triggered pure fusion bomb? Yikes! Not actually…

I think the most efficient means of delivering so much xrays that kilograms of material can fuse is with the primary stage of an hbomb, which is just an implosion fission bomb. I wouldn't be too worried about this test creating a new weapon.

However... In the early 80s, the SDI initiative aimed to have orbiting satellites that utilized x-ray lasers to shoot down incoming warheads. The theory of these were you had h-bombs in orbit, with long cylinders of a material that would amplify the x-rays from the bomb. You'd point these at the incoming warheads and trigger the bomb and (chefs kiss) you have beams of xrays that would destroy warheads.

One of the major reasons this was skuttled, was that the test they used to find a material they thought amplified xrays was flawed (see below).

With the test-ban treaty, they weren't able to test any other materials. Now we have a facility that tests materials to amplify x-rays...

Sidenote: The test was, explode a bomb in a tunnel, shut the tunnel down with explosives to trap the shockwave, then use the xrays to test materials to withstand x-rays as well as amplify them. Teller thought they had seen amplification and sold the military on the satellite idea. Another scientist, thought it was a secondary thermal effect on Oxygen. There is an interesting story about the back and forth, and the pressure to have another scientist lose his credentials for disagreeing with Teller, that is a good follow on to the Oppenheimer story. https://en.wikipedia.org/wiki/Project_Excalibur

Re: LK-99 isn’t a superconductor

#709

Post by svara »

fnordpiglet wrote: post #546

I think it’s a fairly interesting story over all, and it feels like exactly how science should happen. We are humans and easily deluded. We fall easily for things we wish to be true. The fascinating story behind LK99 is incredibly human - including the rushing a preprint out to secure a noble prize by one of the researchers who was being excluded. The fascinating part to me was the fact engineers and scientists could…

A lot of people, myself included, are disappointed about how "science happened" here and absolutely don't share the view that it should be like this.

You're right that the system ultimately worked.

But doing things "well" isn't just to win some aesthetics contest. It's essential precisely because, due to all our human flaws, it's too easy to delude yourself by doing sloppy work.

In this case, doing sloppy work has won the authors international fame and attention -- an insult to all those who do their experiments properly.

The LK-99 authors probably didn't do themselves any favors in the long run, but it is easy to think of examples where sloppy work leads to some quick social media wins, but the topic is not as sexy so ultimately isn't scrutinized in the same way.

Social media clout is already playing a role in hiring decisions, and social media is only becoming more important. If they haven't already done so, it's just a matter of time before funding agencies factor it into their decisions.

Performative show science designed to wow a mass public is exactly what we don't need.

These things actually require real, deep study, talent, and tens of thousands of hours of hard work to do and assess properly. The people doing that need to be able to do their work in peace without needing to pander to crowds.

Re: LK-99 isn’t a superconductor

#710

Post by kergonath »

benj111 wrote: post #683
kergonath wrote: post #666

Earlier quoted context omitted.

Aluminium and copper in cables are crystals. The crystal bit is not the problem.

I'm not sure of the correct scientific language here. As far as I'm aware this is a brittle /inflexible material so my point about the mechanical properties still stands. And when people refer to growing crystals, that generally refers to a particular kind of crystal. Ive never heard of anyone growing aluminium crystals, except if it's a compound, and then you get a crystal like we think of when we say crystals.

> As far as I'm aware this is a brittle /inflexible material so my point about the mechanical properties still stands.

Yes. You want them to be ductile (malleable, or that can be deformed permanently in less-technical language). Although they could also be flexible (meaning that they can deform, but go back to their natural shape if we stop applying a force), as in the case of fibre optics cables, which are actually not crystals but quite brittle.

The interesting twist is that a solid pretty much has to be a crystal to be malleable. Almost all the metals you can think of are in their crystalline state.

> And when people refer to growing crystals, that generally refers to a particular kind of crystal.

I don’t know. From my experience people equate crystals with shiny things without really thinking about it. But this is HN, and we should try to be a bit better than a random person on the street. After all, most people don’t know a web browser from an OS, but I would be ridiculed if I make that confusion here.

It is a wonderful community where you are almost certain to discuss with some experts in pretty much any given field, it is a great opportunity to learn and grow.

> Ive never heard of anyone growing aluminium crystals

If you’ve seen solid aluminium, then you’ve seen it as a crystal. It is pretty much impossible with common techniques to get non-crystalline solid aluminium.

> except if it's a compound, and then you get a crystal like we think of when we say crystals.

That’s the thing, I don’t know what you think of when you say “crystal”. In actual fact, a crystal is a state of condensed matter in which atoms or ions are aligned in a 3-dimensional pattern that can be replicated to fill the space. In the case of aluminium, you can actually see how the atoms are arranged in a periodic way in articles such as this one (figure 3): https://www.researchgate.net/publication/323423565_Anomalous... . There are many other examples, and it is absolutely fascinating. We have the tools to count atoms and see the structure of the material!

And it is undoubtedly a crystal.

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