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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

#851

Post by BizarroLand »

Dylan16807 wrote: post #372
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…

That's just a list of good inventions. GPS, disposable razor, many of these are not impactful enough to be "black swan but good". And things like clocks and batteries were slowly refined over many, many years, so they don't fit either.

I wonder if the lead acid battery or the lithium battery would be more appropriate to put on the list.

Lead acid got us from, what 1940 to 2005? Something like that? But the utility of Lithium Batteries has blown what was already a gigantic market even wider open.

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

#852

Post by [deleted] »

elfbargpt wrote: post #742

EDIT: This is probably fake. The account was just created and can't find any info online. Also the pellet returns to its starting position for some reason. Just saw another unconfirmed replication here: https://twitter.com/instsondaw/status/1687433935012139008?s=... Found their process really fascinating, apparently they create L-99 powder, sort it by meissner effect, then press the "high meissner effect" powder toge…

[deleted]

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

#853

Post by davrosthedalek »

svnt wrote: post #156
postalrat wrote: post #134

Earlier quoted context omitted.

If you can't answer the question then you won't ever understand how to measure zero resistance.

It's a limitation of the most basic approach to the problem (measuring resistance), but not a limitation of every approach (such as measuring current). You can inject a current into a superconducting coil and take measurements of the resultant magnetic field as the current circles for an indefinite period of time. I'm not able to see how this approach analogizes to water in a cup.

I don't think that works as advertised: Any measurement of the current will likely produce a magnetic field itself -- for example from the current in a Hall probe. This current will induct a small, opposite current into the superconducting coil. So the current will go down.

And even if not, what you would need is to measure the change of the field over time. This has finite resolution, so you can't distinguish no resistance from very very small resistance.

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

#854

Post by sigmar »

cthalupa wrote: post #812
elfbargpt wrote: post #742

EDIT: This is probably fake. The account was just created and can't find any info online. Also the pellet returns to its starting position for some reason. Just saw another unconfirmed replication here: https://twitter.com/instsondaw/status/1687433935012139008?s=... Found their process really fascinating, apparently they create L-99 powder, sort it by meissner effect, then press the "high meissner effect" powder toge…

The covering over the magnet is almost certainly to hide the array of electromagnets underneath. You can find a variety of electromagnet toys that will do this exact thing.

100%. Weird 3d-printed stand is a big tell. Plus the close up on the pellet that seems painted to be black. Wish people would be more skeptical of spreading this type of stuff from newly created accounts

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

#855

Post by minsc_and_boo »

jliptzin wrote: post #198
someplaceguy wrote: post #141

Earlier quoted context omitted.

It would have been more convincing if you had given real past examples rather than speculative future ones :) Although I'm pretty sure there are plenty that many people can think of, so it doesn't really detract much from your point.

Antibiotics Electricity Internal combustion engine Flight Li-Ion batteries Radio communication

Yeah, was wondering where the combustion engine came in. It revolutionized agriculture.

Also, tea making was a huge sanitary step forward.

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

#856

Post by aqme28 »

elfbargpt wrote: post #742

EDIT: This is probably fake. The account was just created and can't find any info online. Also the pellet returns to its starting position for some reason. Just saw another unconfirmed replication here: https://twitter.com/instsondaw/status/1687433935012139008?s=... Found their process really fascinating, apparently they create L-99 powder, sort it by meissner effect, then press the "high meissner effect" powder toge…

That looks and acts like pyrolitic graphite over a magnet array. If that institute weren’t also pseudonymous I’d maybe believe them a little more.

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

#857

Post by [deleted] »

gcr wrote: post #848
pineconewarrior wrote: post #783

Earlier quoted context omitted.

I tried searching this strange string of nouns but was met with some strange results. What are you referencing?

Iris Alexandra studies plants in Russia, and also dabbles in chemistry from her (home?) lab. Over this past weekend, she's been working on replicating the LK-99 results herself, heaping a bunch of lighthearted scorn in the process in typical Soviet style. It's highly entertaining, so she's gotten herself a bit of a following online. People are badmouthing her in part because she's openly plural and trans and lesbian…

[deleted]

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

#858

Post by JRKrause »

adrian_b wrote: post #447
httpz wrote: post #44

Earlier quoted context omitted.

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.

I believe that with the synthesis method proposed by the Korean team, i.e. by the chemical reaction between a certain kind of lead sulfate with copper phosphide, the chances of progress are slim. The Korean team appears to have been stuck for several years by the lack of reproducibility of this synthesis method. While it was a great discovery that has shown that this material must have some very interesting propertie…

Drawing from melt to achieve a consistent crystal orientation was my first thought as well.

Looking at the Griffin paper, the Pb(2) site is described as being 1.08eV 'more energetically favorable'. I am having trouble understanding what this means.

Years back I did MOCVD semiconductor fabrication research, I never reached a mastery of it but I am still trying to leverage that understanding here.

During growth, adatoms that incorporate into proper crystal lattice locations enter a lower energy state compared to those in imperfect locations. The energy state is lower in the sense that it requires more energy to remove them from that location. Hence careful control of temperature allows you to selectively favor incorporation into these low energy locations e.g. choose a temperature high enough to remove adatoms from 'imperfect' locations but low enough to not remove them from 'perfect' (low energy) locations.

So when the author says 'energetically favorable' am I to understand this means the Pb(2) location represents a lower energy state (i.e. more difficult to remove Cu from this location) or the opposite? Or something else entirely?

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

#859

Post by bunniez »

lifthrasiir wrote: post #384

So what the heck has happened with LK-99 really? (Disclaimer: I'm no physicist nor chemist, but I have co-written a report on three LK-99 papers [1] and am tracking the Twitter discussion as much as I can. I also got some help from knowledgable friends---much thanks for proof-reading.) It turned out that LK folks were not talking about some stupid shit. Specifically they were one of the last believers of long-forgott…

It's Chwe/Choi, not Chair.

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

#860

Post by caconym_ »

balaji1 wrote: post #265
caconym_ wrote: post #28

Earlier quoted context omitted.

I have heard people much more knowledgeable than me say that measuring true zero resistance is actually quite difficult and takes some degree of specialized equipment, especially with such small samples. That may be part of it.

so none of the previous more esoteric superconductors were ever measure for zero resistance?

I'm not sure how you're getting that from my comment.
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