We now believe that the game is over. LK-99 is not a superconductor

https://twitter.com/condensed_the/status/1688747919866814464

by m101 • 3 years ago

57 81 3 years ago

twitter.com

fdgjgbdfhgb• 3 years ago

https://nitter.net/condensed_the/status/1688747919866814464

santiagobasulto• 3 years ago

Question for the smart HN community:

If it's proven that LK-99 is NOT a superconductor, will still have any "real use"? Or it's going to be completely worthless. Is it "dihcotomic"? Either it's a superconductor and it's helpful for humanity, or it's not and it's completely worthless. Or being "enough" good of a conductor might have applications as well?

Thanks!

seewhydee2• 3 years ago

Contrary to the linked tweet, there's some reason to think its diagmagnetism is pretty interesting. It might be the second most diamagnetic non-superconductive material known. Why this may happen may keep condensed matter physicists entertained for a while. Very little chance of direct technologicalapplications for the foreseeable future, though.

taylodl• 3 years ago

Very little chance of direct technologicalapplications for the foreseeable future, though.

Which means it's worthless. Remember, oil was "worthless" too when it was first discovered...

hackerlight• 3 years ago

If this were true, would CMTC word the tweet like this:

Enquiring minds want to know: Is diamagnetism not interesting? The answer is that NO, diamagnetism is NOT interesting, many materials (e.g. Pb, Cu, P going into LK99) are diamagnetic. It is a run of the mill property. (There are more results, but CMTC cannot divulge them yet.)

mg• 3 years ago

If LK-99 turns out to be a hoax, would it be the one with the biggest media attention ever?

sebzim4500• 3 years ago

Maybe but I doubt it's an intentional hoax. It's much more likely to be a mistake.

nisegami3• 3 years ago

To use a word like hoax would require at least some hint of the authors falsifying data or intentionally misrepresenting things. LK-99 is still very magnetically interesting even if it is not a superconductor. Interpreting those interesting behaviors is where things seem to have gone wrong.

fredoralive• 3 years ago

Social media attention perhaps? Mainstream media doesn't seem to have been paying much attention, and generally rather cautious over the whole thing.

bigbacaloa2• 3 years ago

Nothing compared to cold fusion

hnlmorg• 3 years ago

That was my immediate thought too. That was an interesting time to be alive.

fullstackchris• 3 years ago

Definitely not. This definitely sounds like recency bias. I'll bet 9/10 of your non hacker / engineering family/friends don't even know what LK-99 is. I know thats the case for me at least.

eythian• 3 years ago

Not a hoax but from memory a very premature announcement of results was that one from NASA about evidence of biological processes in a Mars rock.

https://www.amnh.org/learn-teach/curriculum-collections/cosm...

jacquesm• 3 years ago

'hoax' is a very expensive word.

he0001• 3 years ago

First time I ever heard of it. A quick search and the majority of news articles are skeptical. Who hyped it?

lodovic• 3 years ago

In the late eighties, Fleischmann & Pons claimed to have invented room-temperature nuclear fusion. Now that was a media circus.

cfcf14• 3 years ago

Was fun while it lasted! Will be interesting watching the internal story of the original lab unfold as it all becomes public eventually.

calderknight2• 3 years ago

Just because a Twitter said it's over doesn't mean it's over. Prediction markets still think there's a ~1/5 chance of it being legit.

doitLP• 3 years ago

Can you share which markets your following?

ranting-moth• 3 years ago

No it wasn't. Things like this (or at least the dubious media frenzy around this) erode public's trust in science.

alexmolas4• 3 years ago

Science is like that. The problem is not with science or with this material not being super-conducting. The problem is with how science is explained in media. Failing to test hypothesis is a critical step in the scientific method.

gus_massa• 3 years ago

It's important that public understand the difference between a preprint in arXiv, a paper in a serious peer review journal and the truth.

We've seen a lot of miracle cures during the covid-19 epidemic where all the support was a bunch of preprints (and some of the preprints were horrible, I read a few of them to write angry comments in HN).

A paper in a serious peer review journal (if possible/relevant preregistered and with a randomized controlled group) is much better evidence, but it still can be wrong.

tetrep• 3 years ago

Uhhhhh, as trustworthy as the source may or may not be (I have no idea who controls that account), I feel like such strong statements should directly reference strong evidence. I don't see any evidence supplied, only a very strong statement:

With a great deal of sadness, we now believe that the game is over. LK99 is NOT a superconductor, not even at room temperatures (or at very low temperatures). It is a very highly resistive poor quality material. Period. No point in fighting with the truth. Data have spoken.

What data?????

nisegami3• 3 years ago

This study https://arxiv.org/abs/2308.03110

bena• 3 years ago

What data is there that it is?

Why is not the initial claim a strong statement? And if the strong evidence supplied is the method to reproduce and no one can reproduce, then that should be evidence that their evidence is lacking and therefore their original claim is suspect.

Until someone can reliably reproduce the claims of LK99, it remains speculation.

carbotaniuman• 3 years ago

There's a study by the authors? I mean if they just said that I was a hoax by the authors that'd be one thing, but they did specifically mention the data has spoken so...

ajross3• 3 years ago

I feel like such strong statements should directly reference strong evidence

That's not the way the burden of proof goes! Consider "Fluoride Toothpaste is not a Superconductor".

What you want is conspiracy logic: assume something interesting is probably true based on weak evidence (a handful of videos on twitter seems like table stakes in this particular controversy), and then when people deny it you demand that it "should directly reference strong evidence".

tmpX7dMeXU• 3 years ago

This is a naive view of the burden of proof. The reality is that anyone that actually cares already knows the situation: we are waiting on reproductions. This Tweet pretty clearly implies that there’s been some sort of new insight. That’s the obvious and intended plain language effect it’s having. Ham-fistedly applying “burden of proof!” Is just being tone deaf.

peterdsharpe• 3 years ago

There is a difference between saying "We believe LK-99 is NOT a superconductor" and "We do not believe LK-99 is a superconductor". The former is a hypothesis, the latter is a rejection of a hypothesis. The latter is really just expressing a return to an agnostic base state. Hence, the former requires evidence, and the latter is the null hypothesis.

thumbuddy2• 3 years ago

Probably not accounts trying to tip the market. Pay no attention to social media these days. Pay only slight attention to scientific articles. Pay more attention to preprints knowing they are preprints.

Cthulhu_2• 3 years ago

Scroll up a little; it's the last ~tweet~ X in a thread of more scienticious ~tweets~ exes.

sshine• 3 years ago

Now that twitter became X, if you're lacking a better verb instead of tweet:

  excrete

twtxthrow• 3 years ago

Twitter no longer provides context unless you're logged in. You can currently view a single tweet if directly linked, but not the surrounding thread or replies.

cassianoleal• 3 years ago

There's nothing to scroll to. Nothing above, nothing below. Probably because I don't have an account.

prof-dr-ir• 3 years ago

You may not have seen it but the tweet is part of a thread. The thread mentions exactly the data you ask for.

And, you may not have seen it but the account is that of the condensed matter theory center at the university of Maryland. The people working there are at https://www.physics.umd.edu/cmtc/people.html .

stathibus• 3 years ago

The UMD folks are some of the best in the business.

politelemon2• 3 years ago

I can't see anything on Twitter these days except for the single comment itself. The thread and replies have disappeared.

brmgb• 3 years ago

Anyone has a link to some communication from the university of Maryland which is not written by a teenager? They must be one if they spent time trying to reproduce the material.

bowsamic• 3 years ago

This Twitter account has been raging about “normies speculating on science” since the beginning

hunta2097• 3 years ago

This is a better link (I hate linking to twitter these days):

https://uk.unofficialbird.com/condensed_the/status/168874791...

lamontcg5• 3 years ago

I feel like such strong statements should directly reference strong evidence.

They did link the strong evidence upthread:

https://arxiv.org/abs/2308.03110

To conclude, we have observed a semiconductor-like, non-superconducting electric property in our LK-99-like synthetic samples, along with diamagnetic and soft-ferromagnetic properties arising from supposedly different phases of the mixed product. Our results suggest that one needs to be cautious when interpreting half-levitation observations as evidence for net levitating forces (and, further, as evidence for the Meissner effect). The presence of ferromagnetism in a Pb-Cu-P-O system is somewhat unexpected, as we are not aware of previous reports of materials with related properties. The presence of a flat-bandlike electronic structure in Pb10−xCux(PO4)6O, as revealed in a recent calculation [14, 18], might be able to give rise to such spontaneous ferromagnetism, which warrants further investigation.

So, they replicated the "half levitation" effect and found it had nothing to do with superconductivity. Little chunks of it have ferromagnetic and diamagnetic properties along with it being a semiconductor. Weird, but no evidence at all of superconductivity.

Doesn't explain the videos of fully levitating samples, but those are easily faked and none of them have been very plausible and could just be attention seeking or attempts to manipulate stock markets.

Still should get replicated and those questions that the arxiv preprint raise should really get investigated and answered, but it pretty strongly looks like we're investigating a novel semiconductor now, not a superconductor.

andai• 3 years ago

In previous threads I read that this material is very tricky to make, that nobody has succeeded in making a pure sample, and therefore we should expect many negative results and that they don't necessarily mean anything conclusive.

nisegami3• 3 years ago

What's different here is that this sample is exhibiting some of the properties that a successful sample would, indicating that this is not an outright dud. They also seem to have an explanation for why/how they might observe those properties but not superconductivity.

This is in contrast to someone claiming their sample did not exhibit any of the properties of LK-99 at all.

lifthrasiir• 3 years ago

But that's not enough, because this sample alone doesn't explain the extreme variability of other samples. This conclusion is only possible under the assumption that all other samples are bad or incorrectly measured---a highly unlikely event.

In particular they were needlessly critical of Southeast University before [1], which reported the increasing resistance up to ~230 K, then a sudden drop til ~255 K, then back to the normalish curve. I previously criticised that the purported "zero resistance" below ~110 K is misleading, while I was unsure about the drop, but at least it does show the completely opposite trend to the PKU result and CMTC should have explained (or refuted) this as well.

[1] https://twitter.com/condensed_the/status/1686895266329174016

alexmolas4• 3 years ago

It is a very highly resistive poor quality material. Period. No point in fighting with the truth. Data have spoken.

The way this phrase is worded is weird in my opinion. It sounds more like a political statement rather than a scientific one.

harrid2• 3 years ago

This isn't the first unprofessional message from that Twitter account during the lk99 saga. Their biased tone makes them untrustworthy. Even more than anime girl et al

lamontcg5• 3 years ago

They're citing a study from the International Center for Quantum Materials at Peking University in Beijing (which has several Alumni from the Condensed Matter Theory Center at U of Maryland which is the twitter account) which goes into the matter in some depth and finds that chunks of the material are ferromagnetic and some chunks are diamagnetic and the whole thing is a semiconductor. They also replicate the half-levitation effect from the original video and which some people have replicated:

https://arxiv.org/pdf/2308.03110.pdf

The twitter account may have had a biased tone because they're actual experts and qualified to have a strong opinion.

Cthulhu_2• 3 years ago

It's a tweet, the more carefully worded stuff is in scientific papers. I don't mind. The scientists can be colloquial on twitter if they're formal in the papers, like how pop science can turn "we have detected these wavelengths in a handful of photons from this point in space" into "EXTRATERRESTRIAL LIFE DISCOVERED IN BLUE GOLDILOCKS ZONE EXOPLANET"

JoeAltmaier3• 3 years ago

Is somebody trying to manipulate the market? With random unsupported tweets? Good luck with that.

thumbuddy2• 3 years ago

It's surprisingly effective...

gerikson2• 3 years ago

What market?

JoeAltmaier3• 3 years ago

e.g. https://finance.yahoo.com/quote/AMSC

Which is indeed down today

bigbacaloa2• 3 years ago

https://arxiv.org/abs/2308.03110

JaneLovesDotNet• 3 years ago

I wonder if there's been a scientific study that tries to correlate the tone of a statement, with its reliability.

My gut feel is that such emotionally charged statements are likely inversely correlated with accuracy.

I'm surprised this is the twitter account of a reputable organization.

skc• 3 years ago

This whole saga has still been thoroughly exhilarating and compelling. The sort of stuff that in the past might have nudged young people into the sciences.

Rather than being deflated, I want more of this.

bhouston• 3 years ago

The prediction markets still give a 25% chance of it being an SC at room temperature?

https://manifold.markets/QuantumObserver/will-the-lk99-room-...

This other prediction market only gives it a 5% chance of turning out:

https://www.metaculus.com/questions/18090/room-temp-supercon...

IF the game is over, shouldn't arbitrage be possible between these various markets? I guess the timeline is very long for these bets and time is opportunity.

simplyskeptic• 3 years ago

the prediction markets? why don't we just flip coins over it, that sounds scientific as well!

tarsinge• 3 years ago

Markets are just the average sentiment of a mass of greedy people trying to make a buck, there is no inherent prediction power.

CyberDildonics• 3 years ago

The prediction markets still give a 25% chance of it being an SC at room temperature?

Prediction markets are just uninformed gambling? They don't mean anything if the money is from people with low information? Don't rely on a prediction market to predict validity of a supposed scientific breakthrough?

selestify• 3 years ago

They don't mean anything if the money is from people with low information?

Why wouldn’t that incentivize someone with high information to come in and make a quick buck?

unpopularopp• 3 years ago

The whole LK99 saga reminds me to, not surprisingly, another korean story

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

OscarCunningham• 3 years ago

I've been using the prediction market https://manifold.markets/QuantumObserver/will-the-lk99-room-... as a way to track consensus opinion without having the expertise myself. It's currently near 20%, down from 30% in the last day. So we're not quite at the 'game over' phase.

hooande• 3 years ago

I think this was overall positive as a social phenomenon. It did not result in a superconductor future, but it got a lot of people interested in science and practical experiments. The biggest cost was several labs doing work they wouldn't have done otherwise. And that seems fairly minor when compared to the cultural exposure that their work received.

It's unfortunate that it probably won't work out. But this was fun. Good story, good experience.

out_of_protocol• 3 years ago

ever heard of Russell's teapot https://en.wikipedia.org/wiki/Russell%27s_teapot ?

LK99 is more like broad area than very specific substance

awwkaw• 3 years ago

What really annoys me is that we have not seen a single reproduction of LK-99 yet.

A lot of the arxiv papers will measure PXRD. Then they will say stuff like "the position of the peaks is almost identical" (https://arxiv.org/pdf/2308.03110.pdf) (emphasis is mine).

Anyone who knows anything about diffraction knows that almost identical means different.

The original paper specified that LK-99 requires a 0.48% contraction of the unit cell volume. if you are off by a small fraction (either from over- or under-doping) the sample is not LK-99. it is something different.

so far all "reproduction" papers have stated that they created the wrong material, then gone on to show that it does not behave as a superconductor.

I'm not saying that LK-99 is definitely a room temperature superconductor, only that I have not seen a single reproduction attempt actually report the same unit cell parameters as reported by the original paper. Thus not a single reproduction attempt has thus far reproduced LK-99.

We now believe that the game is over. LK-99 is not a superconductor

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