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LK-99 isn’t a superconductor

nature.com

651–660 of 754 posts

Re: LK-99 isn’t a superconductor

#652

Earlier quoted context omitted.

Amen. When someone does the math and adds up the winners and losers in all this, one clear winner will be this video from Asianometry, entitled The History of Superconductors (Before LK-99)[1]. It only lightly touched on LK-99 itself, but did an excellent job going through the actual science-based history of superconductors, covering in particular detail previous hype waves. A major point is that the YBCO superconduc…

REBCO is revolutionizing fusion reactors. Several companies are using it to build tokamaks with the same performance as ITER, but in a tenth the size. REBCO supports stronger magnetic fields, and conveniently, tokamak output scales with the fourth power of magnetic field strength.

> same performance as ITER, but in a tenth the size

So instead of being 400 times the volume of a PWR with the same gross power output, they're just 40 times the volume. It's no panacea to the economic challenges facing fusion.

The other way to get high volumetric power density is go with a configuration of higher beta, the ratio of plasma pressure to magnetic pressure (fusion power at a given magnetic field scales as beta^2). Helion isn't using superconductors at all.

Re: LK-99 isn’t a superconductor

#653

Earlier quoted context omitted.

It's not over yet, at least not definitively. Nature Magazine like every other source so far is basing its comments on the attempted replications using the leaked paper. It's considered fairly certain at this point that the paper was incomplete/not enough to duplicate the material. The full paper with the original samples were reportedly sent to Korea University of Science and Technology for examination. That lab gro…

Of course there's some sour grapes in Nature's article, as arxiv.org has had the best exposure it's likely to get in years. The more that publish there, the fewer who publish behind firewalls, etc. For starters, Nature's reprints are hellishly expensive.

And Nature is still trying to whitewash its own reputation for publishing a very high visibility paper on superconduction that they had to retract.

Re: LK-99 isn’t a superconductor

#654

It’s disappointing news but the excitement and amount of replication on this paper was pretty fun to witness and experience. To me the most interesting part was everyone talking about potential consequences, uses, the order of magnitude improvements we’d see in certain costs or areas. Pumps, MRIs, power grids, chips, etc. Great reminder what materials science can do to some underlying economics.

While I was very skeptical of the base claims of LK99 (extrodinary evidence required), I did sort of fall a little bit for the hype of what this kind of material could be used for. Mostly in terms of computer clock rates and used in batteries. Turns out what seemed intuitive at first was mostly wrong. But then that is what happens a lot in various fields. Something that seems obvious isn't done because those that act…

I'd settle for regular evidence: a nice paper from a reputable lab that replicates the findings of the original team. Extraordinary evidence would be required for non standard model physics or aliens or something like that.

Re: LK-99 isn’t a superconductor

#655

Earlier quoted context omitted.

Amen. When someone does the math and adds up the winners and losers in all this, one clear winner will be this video from Asianometry, entitled The History of Superconductors (Before LK-99)[1]. It only lightly touched on LK-99 itself, but did an excellent job going through the actual science-based history of superconductors, covering in particular detail previous hype waves. A major point is that the YBCO superconduc…

REBCO is revolutionizing fusion reactors. Several companies are using it to build tokamaks with the same performance as ITER, but in a tenth the size. REBCO supports stronger magnetic fields, and conveniently, tokamak output scales with the fourth power of magnetic field strength.

REBCO was a bigger deal for fusion than LK99 would have been. We can't make tokamaks smaller, the magnetic forces would rip them apart.

Re: LK-99 isn’t a superconductor

#656

Earlier quoted context omitted.

> transmission lines are already pretty efficient and we already choose less efficient materials for cost You're correct, and this highlights a problem I often see in discussions: "efficiency" just is a measure of benefit/cost. Without knowing the units of benefit and cost, people aren't making meaningful statements when they say "efficient". The important efficiency of transmission lines is capacity per dollar, not…

This is an absolutely disingenuous point that compares the cost of full-economy-of-scale tech to literal one off R&D prototypes. Maybe new technology made in a lab can one day scale up and compete against current low-cost high-scale solutions. Crazy idea, I know. However, trying to artificially limit all discussion about R&D and future tech by claiming "it's more expensive than fully scaled solutions" has got to be f…

Still isn't going to work.

>material requiring lab crystallization

How are you going to string a crystals between towers? The material properties are all wrong for this application.

Re: LK-99 isn’t a superconductor

#657

Earlier quoted context omitted.

> transmission lines are already pretty efficient and we already choose less efficient materials for cost You're correct, and this highlights a problem I often see in discussions: "efficiency" just is a measure of benefit/cost. Without knowing the units of benefit and cost, people aren't making meaningful statements when they say "efficient". The important efficiency of transmission lines is capacity per dollar, not…

This is an absolutely disingenuous point that compares the cost of full-economy-of-scale tech to literal one off R&D prototypes. Maybe new technology made in a lab can one day scale up and compete against current low-cost high-scale solutions. Crazy idea, I know. However, trying to artificially limit all discussion about R&D and future tech by claiming "it's more expensive than fully scaled solutions" has got to be f…

No, switching from raw aluminium to an obscure synthesised compound is not going to be worth it for a few % efficieny gain. We've had centuries of "scale up" with copper and it's still not worth it.

Re: LK-99 isn’t a superconductor

#658
post #412

Earlier quoted context omitted.

Am not the author of that comment, but the fact that comes to mind is that aluminum is used for virtually all transmission and distribution lines - for price reasons - even though copper has better conductivity. If we did discover a room-temperature superconductor, I suspect it would be a while before the cost to produce it in the bulk quantities required for electrical transmission are economically attractive compar…

> it would be a while before the cost to produce it in the bulk quantities required for electrical transmission are economically attractive compared to what’s already available. Note that there is no guarantee that that would ever happen. Electrical resistance is not the only thing you need for something to be an economically efficient power line. While superconductors are by definition excellent in terms of electric…

In theory, we could have had a much better power grid with more transmission. The reasons we don't have nothing to do with the price of aluminium, or the resistive losses of it. It's just difficult to build large-scale infrastructure. Transmission projects typically spend longer in court than actually building them. Superconductors would not change a thing, unless it changed that.

Re: LK-99 isn’t a superconductor

#659

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…

No, this was just bad science from the beginning. I've done experimental physics research and the way this team published their results and how sloppy everything looked is definitely not how science should happen, it's just a great way to ruin your reputation as a scientist (which the original authors thoroughly did). Every PhD student learns to e.g. include proof that an observed effect is not caused by a different…

I don’t think you got my point. I didn’t say their science was well done. I said science worked the way it’s supposed to work. Science can’t depend on everyone being flawless or above board, being unbiased, etc. the entire process - end to end - is built around the idea that we are all flawed, but through collaboration and rigor, we can see past the flaws to some deeper truth. That’s a collective effort. It’s perhaps easier when everything is done really really well. But it’s more impressive when everything is off the rails.

Re: LK-99 isn’t a superconductor

#660

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…

Wow, so in the end you still think science is going to save us? We're completely ignoring science every single day when we go about our thoroughly unsustainable lives. We only like science when it gives us more (like LK-99). We ignore it otherwise. There is no reason to believe science will give us anything more apart from simply wanting it to be true.

I don’t know if anything will save us. I don’t know that’s the job of science regardless. But I believe when science works, it’s amazing and starkly so in a world of so much broken.
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