Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Ferromagnetic half levitation of LK-99-like synthetic samples

arxiv.org

Post reply on HN
Print view View original

71–80 of 331 posts

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#71

Post by danso »

dylan604 wrote: post #44
NovaDudely wrote: post #37

Earlier quoted context omitted.

I have been very cautious on any analysis on LK99 - especially my own. I have mentioned to many people that any potential application of this stuff comes with an 'if it is real'. That IF is doing a lot of heavy lifting and it has to be emphasized. I want this to be a thing, but it doesn't matter how much you want something to be true, it actually HAS to be true. A beautiful elegant idea can be crushed by a single ugl…

[flagged]

These past two weeks, a whole bunch of people who purportedly read all the original LK-99 papers and data and understand the science, swore up and down that the superconductor breakthrough was essentially in the bag, and that we were only waiting for replication

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#72

Post by haldujai »

protastus wrote: post #26
VHRanger wrote: post #4

After reading the r/physics thread on LK-99 [1] I've cooled significantly on the matter. Basically: people who work in SC think the initial science seems very sloppy and the replication attempts don't come close to what you need to demonstrate a RT SC [1] https://www.reddit.com/r/Physics/comments/15i3h9d/lk99_megat...

The SNR of this saga is very low. A speck of something floating under a magnetic field on a blurry video is not proof of room temperature superconductivity. We've seen memes, jokes, shitposting, bravado, Soviet fan fiction, play-by-play updates from non-SMEs cooking stuff under improvised conditions. No actual resistance measurement of LK-99 with a 4 point probe. If this is real, then discoverers found this in 1999,…

Adding on to that: the researchers are from a private corporation that falsely claimed partnerships with several South Korean enterprises and universities which have all disavowed any connection, the "Quantum Energy Research Centre" website has gone private[edit: not suspicious as described in comments below] and the co-authors are apparently feuding over project direction with one of them since removed from the paper.

I know nothing about the subject matter but as a curious layperson I've been surprised a pre-print is being taken so seriously with this background and have assumed people much smarter than me interpret the physics as plausible.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#73

Post by lifthrasiir »

JohnBooty wrote: post #33

What happened to the original LK-99 samples that (allegedly) displayed SC properties? Were they just thrown in the dustbin, or what? I haven't seen that question answered or even asked anywhere, but I'm just a layman so maybe I'm not looking in the right places.

There are at least 2 samples definitely produced: one in the original videos and another in the video released by Hyun-Tak Kim via nytimes which definitely look different. It is unclear if the sample sent to KENTECH for the analysis is the first sample or a fresh one. Young-Wan Kwon is also known to have his own sample (confirmed in MML 2023 sightings), but it is unclear whether it's distinct from other samples too.

Interviews with Q-Center folks suggest that the yield is high enough to produce a handful but not large number of samples at once, so there are probably much less than 100 samples available, which might be one of the reasons they were initially hesitant to share samples to others. (There are tons of groups want to get samples, if it's unclear.)

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#74

Post by evanb »

VHRanger wrote: post #11
carabiner wrote: post #9

Earlier quoted context omitted.

People were saying the initial papers were trash in the first day of their release over a week ago, so that's ancient history and immaterial now. Same with the "replications," they're obviously insufficient when they're generating pieces the size of a pin head that can't be attached to probes. All of us are in a holding pattern waiting for some big lab like Argonne to confirm or deny its SC status.

How would you *deny* the SC status? Replications keep failing until everyone is pretty sure it's not it. Proving the absence of something is rare to see.

Cool it down until you DO see a SC transition far below room temperature.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#75

Post by InitialLastName »

dylan604 wrote: post #57
Teever wrote: post #51

Earlier quoted context omitted.

I would prefer if †his conversation wasn't derailed into one about politics.

wasn't trying to go political, but used it as an example of the evidence not fitting your theory. so it's still some what scientific.

There's a concept (presented as a contrast to "objective truth" and "subjective truth") called "intersubjective truth", which refers to ideas that are true because (and only to the extent that) a quorum of people believe they are true. Money, contracts and laws are all only words on a piece of paper in objective value. I can generate all of them myself, but unless other people start to treat them as if they are real they'll have all the power of words on paper. On the other hand, if a system arises where people believe those things are true and have value it can be used to build extraordinary things.

Political systems are full of intersubjectivity (they mostly boil down to "groups of people coordinating societal resources, with the consent of enough of the governed"), so of course politics is an arena where "enough people believe this thing" is sufficient to generate truth.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#76

Post by colordrops »

worrycue wrote: post #39
VHRanger wrote: post #11

Earlier quoted context omitted.

How would you *deny* the SC status? Replications keep failing until everyone is pretty sure it's not it. Proving the absence of something is rare to see.

> How would you deny the SC status? Maybe we should adopt the stance that it’s not a SC by default and have the people asserting that it is prove that it’s a SC.

Or even better adopt no stance on truth value and rather adopt a stance on whether there is sufficient evidence to expend further effort.

No need to guess at the truth. Just remain agnostic until you know the truth.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#77

Post by rurban »

lifthrasiir wrote: post #73
JohnBooty wrote: post #33

What happened to the original LK-99 samples that (allegedly) displayed SC properties? Were they just thrown in the dustbin, or what? I haven't seen that question answered or even asked anywhere, but I'm just a layman so maybe I'm not looking in the right places.

There are at least 2 samples definitely produced: one in the original videos and another in the video released by Hyun-Tak Kim via nytimes which definitely look different. It is unclear if the sample sent to KENTECH for the analysis is the first sample or a fresh one. Young-Wan Kwon is also known to have his own sample (confirmed in MML 2023 sightings), but it is unclear whether it's distinct from other samples too.…

If you cite Korean (or Chinese or Japanese) names, please write them correct. There is no Hyun-Tak Kim, he is called Kim Hyun-Tak. Likewise Kwon Young-Wan.

In Korean it's trivial to detect, in Chinese not so, in Japanese very hard.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#78

Post by lifthrasiir »

haldujai wrote: post #72
protastus wrote: post #26

Earlier quoted context omitted.

The SNR of this saga is very low. A speck of something floating under a magnetic field on a blurry video is not proof of room temperature superconductivity. We've seen memes, jokes, shitposting, bravado, Soviet fan fiction, play-by-play updates from non-SMEs cooking stuff under improvised conditions. No actual resistance measurement of LK-99 with a 4 point probe. If this is real, then discoverers found this in 1999,…

Adding on to that: the researchers are from a private corporation that falsely claimed partnerships with several South Korean enterprises and universities which have all disavowed any connection, the "Quantum Energy Research Centre" website has gone private[edit: not suspicious as described in comments below] and the co-authors are apparently feuding over project direction with one of them since removed from the pape…

> the "Quantum Energy Research Centre" website has gone private

In this particular case however, the website repeatedly hit the daily traffic quota before the closure. So I guess it would be no surprise that the hosting provider [1] forced them to close the website.

[1] The website itself was probably hosted by https://imweb.me/ (the parking page also supports this observation---the asset path and the admin page path matches).

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#79

Post by vbezhenar »

versteegen wrote: post #10
m3kw9 wrote: post #8

Has anyone even seen a ferromagnet stand up like that in a magnetic field?

Yes. https://nitter.net/VanGennepD/status/1688052003216261120 And this new paper finally rigorously explains away all the half-levitation videos. They can no longer be considered any evidence of SC at all.

The only evidence of superconductivity is zero resistance. When you have a coil, pump it with current and let it rest for few years. If the current is still the same, it's superconductor.

Rest are just hints.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#80

Post by hliyan »

According to this: https://twitter.com/Andercot/status/1688598313497694208

"...there is a less well-known exception to this rule called Brauenbecker extension which provides a mathematical proof that levitation is possible with a simple diamagnetic in a dipole field so long as the diamagnetic material mass is very small relative to the strength of the magnetic field."

I was very hopeful in the early days and was following the developments eagerly. Unfortunately, now I'm 99% convinced that LK99 is not a superconductor. Hopefully, what we learned from the saga and the momentum will help advanced the field a bit faster.

Post reply on HN