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Origin of correlated isolated flat bands in LK99

arxiv.org

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Re: Origin of correlated isolated flat bands in LK99

#151

Post by akasakahakada »

fpordeig wrote: post #145
akasakahakada wrote: post #96

Earlier quoted context omitted.

Not an expert but it just happen that my lab is full of DFT folks so I heard a lot about those everyweek. As people above already answered the questions, I gonna talk some extras. 1. Computation cost is large. 1 compute task for a small scale ~100 atoms last about 3 days to 1 week on supercomputer. 2. Search space is hugh. For each composition you can have different atomic (or crystal) structure. And here we are talk…

This looks similar to the protein folding problem. Maybe an AlphaFold-like approach could work?

We exactly considering this since this year. But there are some major problems that cannot be solved in short term.

Inorganic crystal structure database (and there is one database literally this name) is way smaller than what we have for proteins. Also by nature, Transformer is hardly useful for crystals because the crystal is repetitive. You don't throw the same sequence over and over to transformer and hope it will work like magic.

My current understanding is that Graph Neural Network is perfect for this job because graph can exactly describe this kind of repetitive nature of crystal.

Re: Origin of correlated isolated flat bands in LK99

#152

Post by calf »

yinser wrote: post #76
elfbargpt wrote: post #17

Earlier quoted context omitted.

Can anyone explain what this means in relation to the ability to synthesize it in superconducting form? Is there a way to force the Cu to the correct site? Or is looking for a new material with similar properties the way forward

I’m currently in a Twitter space with some accounts who know more about this process and this question was answered a few minutes ago. To summarize: no one has yet found a way to “steer” which sites get Cu and which ones don’t. This paper simultaneously makes LK-99 look like the real deal but also points out there may be more, or much more work, to reliably direct the replacement. Someone in the space said “if you fi…

If some third party scoops a more reliable process that would seem unfortunate for the original group.

Re: Origin of correlated isolated flat bands in LK99

#153

Post by regularfry »

aitchnyu wrote: post #121
yetihehe wrote: post #115

Earlier quoted context omitted.

If using that flip-flop, whole processor will be closer to 100ghz (typically there are multiple transistors which need to stabilise before you have a result of computation). But probably those superconductors could enable even faster transistors and maybe we could get 1THz processors.

Like IDE ribbon cables gave way to sleek SATA cables, we could have another parallel to serial transition from silicon multicore crap to superconducting single core.

We'll get superconducting multicore because as a first step everyone will just map what they already know to the new space. Which is fun.

Re: Origin of correlated isolated flat bands in LK99

#154

Post by regularfry »

jacquesm wrote: post #141
synaesthesisx wrote: post #108

Something incredible to note: it took around 5 years from when the transistor was first developed, to when it started to get integrated into consumer goods. LK-99 appears promising (and at the very least, may lead to other tangentially interesting discoveries), and if this is “it”, we could see commercial applications far sooner, especially if the synthesis is relatively straightforward. We couldn’t be on a more exci…

But that first contact point transistor, even if it degraded rapidly actually worked, the challenges were to package it properly and to make it smaller and more reliable. This stuff, assuming it is all true is more at the level of the first inkling that semiconductor diodes might be a thing. We still have to reach that transistor stage (which would mean we an expensive way to manufacture a small stretch of usable con…

If it has superconducting grains but isn't superconducting in bulk, is it likely that those grains could be separated, oriented, and combined to make a bulk superconductor?

Because I can guess how you'd go about doing the first bit: crush it, put a magnet under it, and scrape off any bits that float...

Re: Origin of correlated isolated flat bands in LK99

#155

Post by regularfry »

0xB31B1B wrote: post #127
wiz21c wrote: post #124

Dumb question: why all the fuss ? I have checked a bit on the web but I fail to grasp the practical consequences of it (I mean if LK99 is the thing)). Could someone explain what could be done with that material ? For example, if we can transport electricity with a super conductor over long dsitances (1000 of kms), then what happens ? Is it just an incremental progress or is it a huge breakthrough ? (I am not much tra…

Huge breakthrough. Energy efficiency is just one gain. This also potentially unlocks major gains in quantum computing, fusion energy, tradition computer chip design allowing another 30 years of moore’s law, batteries with zero energy loss leading to ultra dense batteries and electric aviation

Unfortunately the problem with electric aviation isn't the storage tech. Although having superconductors around would make the ground infrastructure nicer, if the current density limit works out.

Re: Origin of correlated isolated flat bands in LK99

#156

Post by fennecfoxy »

Blackthorn wrote: post #120
dtx1 wrote: post #60

Earlier quoted context omitted.

> generating tonal effects that can't really be replicated. Seems my headphones can replicate it judging from hearing the audio. Am I missing something?

Well, it's the creation rather than the playback that's important, but you aren't really missing anything. It's not like the various waveshaping functionality of those aren't documented, they're entirely reproducible in software.

This is why most "audiophile" stuff is redundant in my mind, a lot of people seem to act like valves have some sort of magic that we cannot profile and just reproduce in software.

But then again there's nothing wrong with people romanticising stuff as long as it's more "valves are cool because they're retro and nostalgic" over "valves are cool because they're objectively better".

Re: Origin of correlated isolated flat bands in LK99

#157

Post by dtx1 »

jacquesm wrote: post #125
aitchnyu wrote: post #121

Earlier quoted context omitted.

Like IDE ribbon cables gave way to sleek SATA cables, we could have another parallel to serial transition from silicon multicore crap to superconducting single core.

No, you'll get superconducting multicore because all that will happen is that the bloat will expand to consume the new cycle budget. This has already happened many times.

I'm looking forward to Chromium version 4201337 needing 20% of my 1Thz CPU to render simple text.

Re: Origin of correlated isolated flat bands in LK99

#158

Post by delfinom »

npunt wrote: post #13
caesil wrote: post #7

Out of curiosity, since this seems like a real inflection point toward trending in that direction, if it becomes increasingly likely that LK-99 or similar material is indeed a high-TC superconductor, what will savvy people be positioning themselves to do? What are good investments? What companies will be started, or what will existing companies be pivoting toward?

> What are good investments? Open-ended research grants to anyone with moderate training in experimental science to just throw shit against the wall and try every last possible combination of something, without concern for 'publish or perish' or jockeying for status in academia. Lets get our smartest and most dedicated technical people back in labs rather than off making CRUD apps for 10x academic wages. If this disc…

I would imagine a lot of discoveries in chemistry that humanity has made were _lucky_ over the course of history.

Re: Origin of correlated isolated flat bands in LK99

#159

Post by [deleted] »

WhereIsTheTruth wrote: post #109
dtx1 wrote: post #3

Even if LK99 turns out to be a dud, it's proven that there's a great need and great opportunity for more direct communication from scientist on their experiments via the internet. Live Stream of the Synthesis, Twitter Threads giving life updates of different teams, etc.

I disagree, what you are asking would just be a way to siphon information, and encourage that kind of rush behavior Korea should protect its students and their work a little more if they want their own TSMC, Texas Instruments of Korea doesn't sound right

[deleted]

Re: Origin of correlated isolated flat bands in LK99

#160

Post by delfinom »

dtx1 wrote: post #3

Even if LK99 turns out to be a dud, it's proven that there's a great need and great opportunity for more direct communication from scientist on their experiments via the internet. Live Stream of the Synthesis, Twitter Threads giving life updates of different teams, etc.

You just sound like you have a social media addiction, particularly to dopamine hits.

Not everyone is addicted nor has the personality to start becoming livestreamers over some experiments.

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