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Electronic Structure of LK-99

arxiv.org

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Re: Electronic Structure of LK-99

#331

Post by gizmondo »

Mistletoe wrote: post #316
aqme28 wrote: post #258

Earlier quoted context omitted.

What makes this hype "manufactured"? I've been very hyped as well ever since I read the arxiv.

Well it isn’t peer reviewed for one. I don’t think people that are a little skeptical are being negative they are just being realistic. We’ve experienced things like this before and some of the hallmarks of the ones that let us down are there in this one. https://en.wikipedia.org/wiki/Pathological_science

It has been peer reviewed - lots of scientists reviewed the paper, found various problems, some are trying to replicate it with varying success so far, some are looking for theoretical explanation. This is the essence of science, not sending it to some journal that just mails the article to the small subset of the same scientists and gather their replies.

https://en.wikipedia.org/wiki/Cargo_cult

Re: Electronic Structure of LK-99

#332

Post by computerfriend »

samhuk wrote: post #282

My ultimate take-away about LK-99 since the start has been that, even if it doesn't turn out to be a holy-grail or whatever, the novel ideas behind the material are incredibly interesting. The idea of causing tiny (~0.5%) crystal lattice shrinkage with cuprate percolation is a really interesting idea. So far, only huge pressures or very low temperatures (i.e. Physics) have been used to cause that shrinkage, therefore…

Physicists were by no means holding the chemists back. Condensed matter is full of chemists, it's the point at which the two subjects meet.

Re: Electronic Structure of LK-99

#333

Post by samhuk »

jhrmnn wrote: post #314
samhuk wrote: post #282

My ultimate take-away about LK-99 since the start has been that, even if it doesn't turn out to be a holy-grail or whatever, the novel ideas behind the material are incredibly interesting. The idea of causing tiny (~0.5%) crystal lattice shrinkage with cuprate percolation is a really interesting idea. So far, only huge pressures or very low temperatures (i.e. Physics) have been used to cause that shrinkage, therefore…

Condensed matter physics and materials chemistry certainly become inseparable in certain areas

Indeed. The separation between "Chemistry" and "Physics" completely breaks down when you start dealing with electron behaviours.

I've actually got a little tin-foil-hat pet theory that Chemistry is slowly dying as it approaches "completion" of its roots (macroscopic phenomena of matter), and is gradually being subsumed by Physics. To at least a silly layman like me, lots of bleeding-edge Chemistry nowadays reads like your average Physics, e.g. doing quantum simulations for protein folding, superconductors, etc.

I'm probably just being silly though, right?

Re: Electronic Structure of LK-99

#334

Post by mensetmanusman »

jpmattia wrote: post #117
bluecoconut wrote: post #93

Earlier quoted context omitted.

To be honest, this is a hunch thing more than a I can teach and explain it thing. To me it's just "a lot of the same stories" that are told about cuprates, and less of a "I can explain the mechanism". Roughly, one of the "properties" that shows up with these materials is that the 3d orbitals of coper atoms are involved in forming the bands near the fermi level. Couple that with the fun story of Cu electron configurat…

> To me it's just "a lot of the same stories" that are told about cuprates, and less of a "I can explain the mechanism". Fair enough, and thanks for the readout. I realized after posting I essentially demanded an explanation as to why the cuprates are high-Tc, which is probably its own Nobel prize.

The internet is one of those places where if you are wrong, someone might well write a Nobel-worthy response just to win the argument.

https://www.wired.com/story/how-an-anonymous-4chan-post-help...

Re: Electronic Structure of LK-99

#335

Post by groby_b »

itsoktocry wrote: post #320
groby_b wrote: post #49

Earlier quoted context omitted.

Emotionally, it was horrible. Societally, it was depressing to see that we'll never be able to tackle any true large problems, we can't even agree on wearing a piece of paper to protect fellow humans. But scientifically? Yeah, I'll go with "exciting". The field seemed to move at a tremendous speed, or at least that's how it looked to me as an outsider. Sequencing within less than a week, extremely rapid movement on t…

> But scientifically? Yeah, I'll go with "exciting". The field seemed to move at a tremendous speed, or at least that's how it looked to me as an outsider. The practical science may have been exciting. Unfortunately "The Science" has been forever tainted thanks to secrets, tight-lips, mis-direction and "just trust us". I think Covid was a net-negative for science.

You're referring to politics. The science was pretty clear the entire time.

Re: Electronic Structure of LK-99

#336

Post by mensetmanusman »

weinzierl wrote: post #238
bluecoconut wrote: post #12

I got my PhD studying band structure of high-tc superconductors (experimentalist, ARPES). These Cu d-d interactions right at the fermi energy give me huge hope. Feels very familiar to other superconductors (re: all the cuprates). (Note: I specifically worked in a lab that was measuring a lot of the d-wave character / gap-energies of various superconductors) All in all, I'm now much more bullish on LK-99 being real su…

This is probably a very stupid question, but why is simply measuring resistance not enough to conclusively prove that it is a superconductor. I mean, isn't zero resistance the defining property?

Because materials interfaces create weird effects.

You would use metals as your leads and create Josephson-junctions-like interfaces.

Basically the abrupt change in electron mobility across materials can cause knock on effects that dominate what you are trying to measure.

Interfacial engineering is one term in materials science that implements best practices for dealing with such challenges.

Re: Electronic Structure of LK-99

#337

Post by sterlind »

yetihehe wrote: post #287
xorbax wrote: post #286

Earlier quoted context omitted.

I think I'd ask you what I'd ask L/K - why do you think it works? They're experimentalists: they didn't find the material from first principles, they appear to have made it and decided to continue. So did you make the engine and notice it's efficiency, or did you find it using first principles where no one else did?

> So did you make the engine and notice it's efficiency, or did you find it using first principles where no one else did? I found it from first principles, I still don't know why no one else thought about it, but it requires sort of splitting and reversing a normal stirling engine inside-out. Since then I've found several attempts at going in that directions which I took, but no one connected all those pieces yet as…

why can't that someone be you? if you've saved up enough for a home with a garage, can't you further save another $10k?

Re: Electronic Structure of LK-99

#338

Post by mensetmanusman »

samhuk wrote: post #333
jhrmnn wrote: post #314

Earlier quoted context omitted.

Condensed matter physics and materials chemistry certainly become inseparable in certain areas

Indeed. The separation between "Chemistry" and "Physics" completely breaks down when you start dealing with electron behaviours. I've actually got a little tin-foil-hat pet theory that Chemistry is slowly dying as it approaches "completion" of its roots (macroscopic phenomena of matter), and is gradually being subsumed by Physics. To at least a silly layman like me, lots of bleeding-edge Chemistry nowadays reads like…

Chemistry has a ton of unsolved problems that are almost unbounded. The big fun one is trying to create the complete graph network of useful chemical reactions so that we can find paths of higher efficiency when making certain molecules.

This compute hard problem will take the world’s chemist to collaborate on a large scale because they don’t have a great database built yet that can enable this.

Re: Electronic Structure of LK-99

#339

Post by objektif »

selimthegrim wrote: post #317
objektif wrote: post #315

Earlier quoted context omitted.

This is the one from the all infamous University of Maryland correct? lol.

They may have been throwing a bit of shade around lately but they are by and large reputable scientists barring whatever SDS’s past MA announcement involvement was. It’s more than just him there.

I do not (almost everyone else too) associate "reputable scientist" with University of Maryland. So they should show a bit of humility.

Re: Electronic Structure of LK-99

#340

Post by NotYourLawyer »

dylan604 wrote: post #78
NotYourLawyer wrote: post #59

Earlier quoted context omitted.

And together, these two phenomena have just sucked all the energy out of the crypto excitation mode.

You think all of the news about crypto fraud might have a chilling effect on the excitation?

Nope.
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