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Successful room temperature ambient-pressure magnetic levitation of LK-99

arxiv.org

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Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#421

Post by austinwade »

WhereIsTheTruth wrote: post #250
nafey wrote: post #209

Earlier quoted context omitted.

This is a South Korean breakthrough

I am not stupid, I know that However, take a look at this: https://en.wikipedia.org/wiki/LK-99#Replication_attempts 0 from both the EU and the US Getting downvoted over this speaks volume ;)

I would assume that many US labs are also attempting to replicate it, but are just not as public as the wikipedia listed attempts. Also US government agencies/labs are probably working around the clock to make and test this stuff but in secrecy.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#422

Post by andbberger »

hwillis wrote: post #383
nocoder wrote: post #139

I get the idea of superconductivity at room temperature in theory. But I don't have enough knowledge to understand in real terms, how will the world change if this is true?

You can't get CT scans very often, because they hit you with large doses of ionizing radiation. Ultrasounds are low-resolution spotlights; you shine them at a particular spot to diagnose something specific. With this you could get an MRI at your annual checkup. You could diagnose all number of diseases like that, not to mention 95% of cancers. Each year your scan is automatically compared to the previous year, and an…

we could do annual scans with current tech. the fundamental limitation of MRI is proton relaxation time, which limits the sampling rate. the path to reducing scan time and thus cost is to use a more sophisticated reconstruction method to reduce the number of required samples. this is being worked on.

i don't have any data here, but I am dubious that a room temperature superconductor will bring down the price of MRI machines. a room temp superconductor only saves you a dewar, about $50k of liquid helium and a cryocooler. you still have to build the rest of the MRI, which is an _extraordinarily_ sensitive instrument

> Fires, particularly house fires would become less common as wires simply stop conducting when they are overloaded.

depends how sharp the phase transition is.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#423

Post by dataflow »

anovikov wrote: post #385
nindalf wrote: post #267

Earlier quoted context omitted.

Auctions, sanitary towels, retirement, banking, disposable razor, sewing machine, canned food, interchangeable parts, antibiotics, solar cells, postage stamp, light bulb, pencil, air conditioning, insurance, dwarf wheat, spreadsheet, cold chain, double entry book-keeping, S-bend, infant formula, clocks, public key cryptography, passports, batteries, printing press, video games, GPS, contraceptive pill, shipping conta…

Passports are not a good invention. They are a dystopian evil we grew to take for granted and even see as something that exists for our own benefit. Before WWI there were no passports and no need for them. Those were Good Old Days that are not coming back. It's weird to see some people seeing some kind of benefit in them.

It's not like we would have free roaming in the modern age if passports weren't a thing. People would still face travel restrictions, they'd just be more nonstandard and unpredictable.

Consider how the days before passports also lacked air travel available to the masses. Even cars has only just started to become commonplace. I don't see how you could possibly have travel that is so cheap, quick, and accessible to such a large population without some way to control who is coming and leaving your country? Especially with how we're quickly making different parts of the planet inhospitable, and given how rapidly populations have risen compared to a century ago.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#424

Post by ayende »

rvnx wrote: post #257
TheSpiceIsLife wrote: post #150

Earlier quoted context omitted.

Nuclear weapons. There hasn’t been a full scale war between major powers since.

350K+ reported casualties just in a year sounds already much https://www.reuters.com/world/europe/ukraine-war-already-wit...

To give some context, Battle of the Somme, lasted 4 months, total casualties: 1m+.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#425

Post by MrYellowP »

dclowd9901 wrote: post #286
nindalf wrote: post #267

Earlier quoted context omitted.

Auctions, sanitary towels, retirement, banking, disposable razor, sewing machine, canned food, interchangeable parts, antibiotics, solar cells, postage stamp, light bulb, pencil, air conditioning, insurance, dwarf wheat, spreadsheet, cold chain, double entry book-keeping, S-bend, infant formula, clocks, public key cryptography, passports, batteries, printing press, video games, GPS, contraceptive pill, shipping conta…

I’ll add some more: Language, standards, the internet, agriculture, glass, sunscreen, resilient rice, sterilization, human flight, spontaneous development of sentient life in the universe… When you think about it all, you start to appreciate how miraculous things actually are.

Does language really count? It emerged as noises and refined over the years. It's not something anyone invented, or even discovered. It simply came to be all by itself, until humanity reached a point where it could be formalized/standardized (idk the proper term, I'm sure you get what I mean).

Regardless ... people's ignorance is showing. Too many never think about the fact that people just 200-100 years ago would have considered modern technology magic.

Imagine showing off to one of these people:

Omfg you're speaking into a flat rectangle!

Omfg it speaks back!

Omfg it shows pictures!

Omfg that box speaks!

Omfg that box speaks and shows people!

O M F G YOU GUYS FLY EVERY DAY???

WHAT DO YOU MEAN, SYPHILIS ISN'T AN ISSUE ANYMORE??? AND THERE'S A PILL PREVENTING PREGNANCY ???????????

It's absolutely amazing.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#427

Post by hgrbrm »

httpz wrote: post #44
cypherpunks01 wrote: post #21

Why are folks trying to prove that this material is a superconductor in roundabout ways, like levitation, dimagnetism, etc? What is the reason they don't just test to see if electrical current flows without resistance? Surely there is something I am missing here.

With the current fabrication process, they're only getting a chunk with LK-99 particles sprinkled in. Since nobody yet knows how to fabricate a pure chunk of LK-99, it'll be hard to measure the true resistance of LK-99.

How do you explain the almost three orders of magnitude drop in resistance in Fig. 6d in one of the original articles ( https://arxiv.org/pdf/2307.12037.pdf ) with a few LK-99 particles sprinkled here an there? There must be a current path along which more than 99.8% of the material is in the supposed superconducting state. So the particles almost touch but not quite yet?

I think the more likely explanation is that the particles do touch each other but the interface is not superconductive. In other words, it is a polycrystalline material, and most of it is LK-99, but the grain boundaries are not a very good conductor. In conventional superconductors grain boundaries don't disrupt superconductivity because they are 3D superconductors, but in this allegedly 1D superconductor the superconducting channels in most cases don't meet at the grain boundaries, so the current has to overcome the resistance of some material that is almost an insulator.

If that is the case it will be difficult to produce a material that is macroscopically superconducting. But I hope researchers will be able to make single crystals that are large enough for resistance measurements so that finally it can be determined if this material is a superconductor or not. For practical uses the best result that can be achieved with this material may be a metal-LK-99 composite where the LK-99 particles lower the resistivity of the metal by 50-90%.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#429

Post by krisoft »

ChuckMcM wrote: post #129

For those experiencing this type of "black swan, but good" event for the first time, it is helpful to recognize that the human tendency to believe that all future "big events" will be dystopian downers, is statistically unsound. For a while I've kept a list of the things that could be "good" swan events, but to be fair I didn't have "room temperature superconductor on that list" :-) Other things that could happen: 1)…

> Fully decoding the cellular mechanism of cells allowing for the curing of any disease, repairing any genetic disorder.

Honestly that doesn’t seem likely to be a black swan event. Not because it is never going to happen, more because it won’t be an event but a slow progression.

It is more likely that as we understand more and more we will be able to cure more and more. It is not like there is some silver bullet piece of research where sudenly we have “fully decoded the celular mechanism”. Plus even if we somehow suddenly and all at once atained all that knowledge (perhaps a flying saucer takes pitty on us and beams down a whole library documenting our cells) it would take a long time while we turn that knowledge into helpfull interventions. And even that progress would be multiple generations long.

It is how becoming a black-belt martial artist is not an “event”. You don’t go from zero to that in one night. It is more of a progression where every day you are about as proficient as you were the previous one, but maybe a tiny bit better. Just applied on a whole species level.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#430

Post by dgb23 »

p1mrx wrote: post #186
HeartStrings wrote: post #166

Earlier quoted context omitted.

Is this actually true?

We would first need to build a superconducting track for the hover scooters (containing magnets) to ride on. Assuming we ever figure out how to mass produce the superconductor inexpensively. Perhaps if the track were arranged in a grid-like pattern, the scooter could use superconducting electromagnets to accelerate and steer.

Somehow I fear such large magnets might come with unwanted side effects?
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