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The first room-temperature ambient-pressure superconductor?

arxiv.org

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Re: The first room-temperature ambient-pressure superconductor?

#331

Post by howmayiannoyyou »

whatshisface wrote: post #262
amluto wrote: post #145

Earlier quoted context omitted.

The actual picture of (poor) levitation in the paper you linked is pretty compelling. This isn’t a complex, noisy measurement showing something that’s related to superconductivity — this is a magnet and a supposed superconductor repelling each other. As far as I know, that’s possible with permanent magnets (and it would be weird, but not impossible, if the group instead synthesized a novel ferromagnet and didn’t noti…

Believe it or not, the levitation effect can be found in non-superconducting materials with a high diamagnetic constant such as pyrolytic carbon. Induced magnetic fields are created by "effective currents," which can occur in zero-resistance systems that are not called superconductors (because they can't conduct across a significant distance, only around a tiny loop) like molecular or atomic orbitals. https://en.wiki…

Diamagnetism was my first reaction when I saw lead, and the addition of copper makes me think eddy current reactivity.

Re: The first room-temperature ambient-pressure superconductor?

#332

Post by whiskeytuesday »

distortionfield wrote: post #254
carabiner wrote: post #159

Earlier quoted context omitted.

Ya no shit. Desperation makes people do dumb things.

You think this team would jeopardize their reputations by faking this data with such easily verifiable and thus refutable claims?

I mean that's almost exactly what happened with cold fusion, not faking so much as convincing yourself. What's the Feynman quote? "The first rule is do not fool yourself and you're the easiest person to fool" - something like that anyway.

Re: The first room-temperature ambient-pressure superconductor?

#333

Post by MayeulC »

littlestymaar wrote: post #237
MayeulC wrote: post #184

Earlier quoted context omitted.

That also means that electrons flow unimpeded from one side to the other. Great for energy transmission (though you can't put too much current, superconductivity breaks down under strong fields). Great for fast circuits, such as CPUs, that don't waste energy just transmitting data. Great for storing energy (in principle) by just making a loop and let current flow indefinitely. Related, great for building powerful mag…

> This one contains lead, which is a non-starter for a lot of applications due to its toxicity. We've been using cadmium-based batteries for ages despite Cadmium being even more toxic than lead, and are still using lead batteries in ICE cars AFAIK. Lead toxicity isn't really a problem unless you burn it, deliver water through it or you put it on paint that end up in kids' mouth…

I agree that it can still be used in a lot of applications, but this would probably restrict its use in everyday items, such as over-the-counter magnetic bearings,long-distance transmission lines, or consumer electronics (RoHS).

Lead batteries for cars are a bit special, as the whole supply chain goes both ways for recycling, while batteries are rather self-contained and not usually exposed to harsh environments.

Though I suspect you are right in the end, as it's a matter of judging the risk vs reward, I wouldn't be surprised if other materials with a similar structure end up performing similarly.

Pb is also quite hard to use in integrated circuits, as far as I know. I am no material scientist, but it could be due to its low melting point or tendency to contaminate other metals.

Re: The first room-temperature ambient-pressure superconductor?

#334

Post by marcosdumay »

sudosysgen wrote: post #155
mitthrowaway2 wrote: post #144

Earlier quoted context omitted.

It probably wouldn't greatly affect the heat generation in a PC, unless the transistors could themselves be replaced with some superconducting alternative. Harnessing the efficiency from that would probably require that the computer be designed as a reversible computer. It would be its own research avenue.

Unfortunately, as soon as you actually use the result of the computation in any kind of practical manner as an output, you break reversibility, though you could make the heat production happen away from the computation.

The idea of reversible computing is that if you only add heat in a few instructions, you can have a much more economical computer. And magnetronics is a good candidate for implementing this, so yeah, computers that use a lot less power are an application too.

Re: The first room-temperature ambient-pressure superconductor?

#335

Post by fluidcruft »

Kirby64 wrote: post #139
traverseda wrote: post #82

Earlier quoted context omitted.

Superconductors are basically perfectly conductive wire. Wires that transfer 100% of power over arbitrary distances and that don't heat up. Obviously there are limits, you can't put arbitrary power over a hair thin filament but as long as you're under that limit you get perfect efficiency. MRI machines can be made a lot simpler as you no longer need to use liquid nitrogen to cool the superconductors. MRI machines cou…

A note about MRI machines: they use liquid helium, not liquid nitrogen. LN2 isn't cold enough. Being able to eliminate liquid helium would be huge, as helium is scarse and quite expensive. Its roughly 10x the cost of LN2 and only going to get more expensive.

They use both liquid helium and liquid nitrogen. The nitrogen is used to cool the helium. On MRI scanners that have come to market in the last few years, helium volume has been reduced at least 100x and is now only a few liters (i.e. previously >1000L and requiring frequent top off to <1L and requiring refill only after emergency/full power loss).

Re: The first room-temperature ambient-pressure superconductor?

#336

Post by hinkley »

alsaaro wrote: post #41
slashdev wrote: post #21

This is an unreviewed preprint coming out of South Korea. If it’s reproducible it would be the biggest scientific discovery of the last hundred years. It will literally reshape the world. However, the most likely thing is they made a mistake and the paper will be withdrawn. But imagine if it’s true.

They claim to have observed the Meisner effect, quantum locking unique to superconductors, a pretty big signal, so more likely fraud than a mistake.

I haven't touched much physics since college. Could the Meisner effect be observed in a material that is not superconducting? Or would that be new physics if it were the case?

I suppose that would be a useful material even if it couldn't be used for high current applications.

Re: The first room-temperature ambient-pressure superconductor?

#337

Post by sudosysgen »

lilgreenland wrote: post #280
skunkworker wrote: post #185

https://www.youtube.com/watch?v=EtVjGWpbE7k This is an unlisted video of the LK-99 film (purportedly)

Isn't this how copper already works without superconductivity? https://www.youtube.com/watch?v=sENgdSF8ppA

Only temporarily. After a fraction of a second the dampening isn't strong enough anymore to prevent the two from entering into contact.

Re: The first room-temperature ambient-pressure superconductor?

#338

Post by aden1ne »

Maxion wrote: post #117
Mizza wrote: post #88

Earlier quoted context omitted.

Sounds like you've got a very interesting weekend project coming up!

The synthesis section honestly looks very simple, I would assume a simple ceramic kiln could be used? You just need PbO, PbSO4, Cu, and P powders.

The powdered lead seems like something you need to be careful with tho. Quite toxic.

Re: The first room-temperature ambient-pressure superconductor?

#339

Post by guerrilla »

floxy wrote: post #217
CamperBob2 wrote: post #152

Earlier quoted context omitted.

The recipe in the paper is so simple that it's giving me Pons-Fleischmann vibes. It reads more like an entry from an alchemist's journal, reproducible with chemicals and equipment you could buy on eBay or Amazon. So, yeah: big if true.

I wonder if anyone has tried to contact one of the authors to confirm the paper is legitimate (i.e. someone isn't spoofing the author's names in order to create chaos).

Good thinking. I'm guessing journalists lurk here so we'll probably find out soon enough.

Re: The first room-temperature ambient-pressure superconductor?

#340

Post by post-it »

carabiner wrote: post #312
inasio wrote: post #239

Earlier quoted context omitted.

One obvious application: your family doctor will have an MRI machine in her office, same for all physio clinics

What are the failure modes for a superconductor MRI? Could it cause a resonance cascade?

Sign me up, I'd like to be one of the biped critters with giant mouths on their stomachs. Short pipeline, very efficient.
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