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LK-99 isn’t a superconductor

nature.com

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Re: LK-99 isn’t a superconductor

#631

Post by yetihehe »

RF_Savage wrote: post #592
dgoldstein0 wrote: post #519

Earlier quoted context omitted.

And gold too. Very expensive to build anything sizable out of it

Gold (2.44x10-8 Ω•m) is worse than copper (1.68x10-8 Ω•m), but better than aluminium (2.82x10-8 Ω•m). It does have excellent anti-corrosion properties. I wonder what kinds of alloys we will see in the potential future with asteroid mining and thus comparatively cheap gold. Imagine replacing lead with gold in industrial applications. Or the stainless steels with a gold component in them.

Probably the most useful mtal from asteroid mining will be platinum for use in catalysts.

Re: LK-99 isn’t a superconductor

#632

Post by usrbinbash »

goodbyesf wrote: post #481
usrbinbash wrote: post #39

One of the good things that came out of this whole story: A very public demonstration, transported through mass and even social media channels, how empiricism and the principle of falsification work, and why they are the only known reliable process for generating knowledge.

> how empiricism and the principle of falsification work, and why they are the only known reliable process for generating knowledge. Only? Math, logic, arts, etc aren't knowledge? What this episode has shown is that people don't know what they are talking about. Especially the ones cheerleading on the science's side.

> Only? Math, logic

Math and logic are as much subjected to falsification as physics or biology. Mathematicians write proofs, and their peers try to find flaws in them.

> arts, etc aren't knowledge?

I am obviously talking about scientific knowledge, and in that regard: No, they aren't. The study of art can be scientific, and is as subjected to empiricism and falsification as everything else. Art in itself however isn't.

If humanity forgot all the works of Mozart and Schubert, it would be a very sad day, but society would still function. If humanity forgot how to make steel, or had to rediscover the fourier transformation, we would have a problem.

Re: LK-99 isn’t a superconductor

#633

Post by hardlianotion »

Cthulhu_ wrote: post #627
hunson_abadeer wrote: post #378

Earlier quoted context omitted.

This is precisely what put me off in these discussions. Not the idea that we might have found a room-temperature superconductor - that part was exciting. It's the part where people confidently talked about its applications without realizing that they probably wouldn't revolutionize CPU performance (Josephson junctions don't seem to work well as non-cryogenic temperatures for reasons unrelated to superconductivity), p…

This is the curse of popular science websites hyping things up; most people, present company included, have no idea what the scientific language means - be it superconductivity, LHC results, or astronomic spectrography. So popular science wraps it in a "what you could do with it. maybe. possibly." Or what it means. And commenters have latched onto it, but a lot is said with an air of confidence, of just-so. "Oh uh, s…

Funny you should mention the solar connectors and electricity interconnections. There is a Morocco -> UK interconnector project that is underway right now.

https://xlinks.co/morocco-uk-power-project/

Re: LK-99 isn’t a superconductor

#634

Post by usrbinbash »

Dylan16807 wrote: post #468
usrbinbash wrote: post #415

Earlier quoted context omitted.

> Cheap doesn't mean free Means cheap enough to be mass produced, and available. > But most importantly, the power grid doesn't lose all that much to resistance Laws of scaling, even a small percentage of power lost to resistence is a hige overall loss, the avoidance of which is desirable. And as I said, this is only the simplest example.

> Means cheap enough to be mass produced, and available. But so are all our existing cables. > Laws of scaling, even a small percentage of power lost to resistence is a hige overall loss, the avoidance of which is desirable. We could cut those losses right now by making the existing cables thicker. But we don't. Even a cheap superconductor might not be used at all in electrical grids, because the benefit isn't worth…

>We could cut those losses right now by making the existing cables thicker. But we don't.

If we could make cables superconducting simply by making them thicker, we wouldn't need superconductors.

> What are the better examples?

Microelectronics for a start. Resistence bleeds heat, heat buildup limits designs. A novel superconducting materials would allow us to make more efficient chips.

As for further examples: https://en.wikipedia.org/wiki/Technological_applications_of_...

Re: LK-99 isn’t a superconductor

#635

Post by usrbinbash »

Dylan16807 wrote: post #470
usrbinbash wrote: post #421

Earlier quoted context omitted.

> 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…

Costs are not just money. There is an environmental cost to making and installing things. Spending the same amount of money on green power generation would probably help the biosphere much more. > making eg. solar farms in remote locations suddenly feasible We can already get losses down to a couple percent per thousand kilometers. Those farms are already feasible.

> We can already get losses down to a couple percent per thousand kilometers.

Yes, and if we could squeeze down these couple percent to a <1%, the same farm would be even better.

Re: LK-99 isn’t a superconductor

#636

Post by magicalhippo »

KSteffensen wrote: post #610
hunson_abadeer wrote: post #378

Earlier quoted context omitted.

This is precisely what put me off in these discussions. Not the idea that we might have found a room-temperature superconductor - that part was exciting. It's the part where people confidently talked about its applications without realizing that they probably wouldn't revolutionize CPU performance (Josephson junctions don't seem to work well as non-cryogenic temperatures for reasons unrelated to superconductivity), p…

A large part of the energy loss in electronics happens in switch-mode Buck-Boost DC-DC converters, as I understand it mainly due to internal resistance in the components used and due to the magnetic field not being directed enough to transfer 100% power between two inductors. Would a cheap room temperature superconductor bring any benefits here?

For "normal" DC-DC converters it's the losses in the semiconductor switches and diodes that dominate[1], unless cheap inductors or capacitors are used.

High-efficiency DC-DC converters often use a resonant tank circuit[1], which supports high-frequency operation and zero-current or zero-volt switching, which together significantly reduces switching losses.

In such a circuit I imagine superconducting inductors/transformers and superconducting capacitors could be beneficial to improving efficiency further.

Keep in mind though that resonant DC-DC converters can reach 98% (or higher) efficiency already[3] with current tech.

[1]: https://www.analog.com/en/technical-articles/an-efficiency-p...

[2]: https://www.monolithicpower.com/understanding-llc-operation-...

[3]: https://ietresearch.onlinelibrary.wiley.com/doi/10.1049/iet-... (random example)

Re: LK-99 isn’t a superconductor

#637

Post by AltruisticGapHN »

I think the positive take here is "an unusually swift resolution of a high-profile puzzle".

So it sounds like the leak was in fact a positive and that overall rewarding people with nobel prizes is detrimental to science.

edit: it's OK to make mistakes. If science focused on EXPERIMENTING instead of trying to be the arbiter of truth on how the world is, we'd progress much farther. Maybe there is a reason why it seems physics has been stuck for the past 50+ years... maybe it is a shift in culture, driven social media, the fear of being wrong, of being shamed by the collective, of using the improper labels, etc. that is holding everyone back.

Re: LK-99 isn’t a superconductor

#638

Post by challenger-derp »

seewhydee wrote: post #538
samhuk wrote: post #197

> When copper oxide superconductors were discovered in 1986, researchers leapt to probe their properties. But nearly four decades later, there is still debate over the material’s superconducting mechanism, says Vishik. Efforts to explain LK-99 came readily. To me, the interesting take-away is that, right at the end. All too often we see peer-review as this slow, inching, excruciating process, particularly in social s…

That German lab should sell LK-99 crystals. I wouldn't mind buying a souvenir for this whole episode!

I'd like to second this. Bonus points if a magnet were included so that the sample could be "levitated" over it. This is definitely a kind of novelty gift suitable for science-y and geeky friends.

Re: LK-99 isn’t a superconductor

#640

Post by kergonath »

SamBam wrote: post #506
elihu wrote: post #434

Earlier quoted context omitted.

Aluminum vs copper is a good example. Another is that we already do use superconducting transmission lines in a few places. We could do more of that, but presumably it's expensive to install and/or maintain otherwise we'd be using it everywhere. I'm not sure what the longest or highest capacity superconducting links currently in existence are.

That have to be kept cool with liquid nitrogen, so it would have to be pretty darn short.

High-temperature ones can be cooler with liquid nitrogen. Standard ones, the ones most commonly used, require liquid helium.
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