[HN Gopher] Flux Pinning in sample of LK-99
___________________________________________________________________
Flux Pinning in sample of LK-99
Author : kochie
Score : 272 points
Date : 2023-08-05 09:55 UTC (13 hours ago)
(HTM) web link (twitter.com)
(TXT) w3m dump (twitter.com)
| eugene3306 wrote:
| Is this material safe to handle?
|
| It feels like this thing soon will start appearing all over ebay
| and aliexpress
| makeworld wrote:
| It has lead in it.
| HDThoreaun wrote:
| Lead is safe to handle, you just can't eat it.
| crote wrote:
| Handling lead tends to result on lead being on your hands,
| which has a nasty tendency to result in lead being on your
| lunch if you are not careful.
| Ancapistani wrote:
| Basic safety precautions are fine.
|
| To put it in perspective: millions of people in the US
| regularly handle ammunition and shoot firearms at indoor
| ranges. Those contain lead in many forms: the projectile
| itself, lead fulminate in the primer compounds, lead
| suspended in the air after firing, etc.
|
| You make sure to have adequate ventilation, don't touch
| your face, and wash your hands when you're done. It's
| important, yes, but not really that big a deal.
| naillo wrote:
| Would that be legal, considering they have a patent (pending)
| for it? Not denying it won't appear anyway just curious
| mensetmanusman wrote:
| It is illegal in places that have rule of law.
|
| This is to create a risk reduction mechanism for investing in
| capital to make this at scale, which will cost on the order
| of $100-500M to scale for world use through trial and error.
|
| If IP is ignored, no business will invest in the initial
| experiments due to first mover disadvantage in game theory.
| Iulioh wrote:
| >If IP is ignored, no business will invest in the initial
| experiments due to first mover disadvantage in game theory.
|
| Not if you belive that
| mensetmanusman wrote:
| This has been shown to be historically true, because
| startup costs can be tens to hundreds of million in R&D.
|
| The business that spends will have their workers
| immediately poached if they don't have IP protecting
| their initial startup costs.
| [deleted]
| TheAceOfHearts wrote:
| I'm not sure how it works, but this was the first result:
|
| > Patents are territorial and must be filed in each country
| where protection is sought.
|
| [0] https://www.stopfakes.gov/article?id=Is-My-US-Patent-
| Good-in...
| jtwaleson wrote:
| Not a patent attorney, but as far as I know: The patent is
| currently pending (as in, being evaluated to see if it will
| be granted). Once it is granted in one country it can be
| expanded to multiple countries within a couple of months,
| given that the first country is part of the Patent
| Cooperation Treaty. So if an invention is marked "patent
| pending", you know you will have the risk of being sued by
| said company at some time in the future if you copy the
| invention.
| foobarian wrote:
| I hope it is. It will be a perfect toy for little kids, right
| along the little ball magnets.
| 0xfaded wrote:
| Those magnets can be deadly to children of swallowed:
|
| https://health.ucdavis.edu/news/headlines/little-magnets-
| are...
| justicz wrote:
| The post just says the video came from BiliBili. Does anyone know
| the actual source? I want to believe but this video is
| suspicious.
| kzrdude wrote:
| To be considered a rumor
|
| > He posted on his personal social media, According to public
| information, he is an assistant engineer in the Department of
| Metallurgical Engineering and Materials of Wuhan University of
| Science and Technology, and is also a doctoral candidate at the
| school.
|
| https://nitter.net/songwenxuan6/status/1687850304803426306
| [deleted]
| est wrote:
| the source is Chinese tiktok (douyin)
|
| https://www.douyin.com/video/7263715495256378659
| phreeza wrote:
| Someone linked to this on the manifold market:
| https://imgur.io/a/AY1oaIO it does look a bit weird to me but I
| am not expert enough to tell if this could be explained by
| optical/compression effects.
| incrudible wrote:
| Looks unlike any compression artifact I have ever seen. Two
| remarkable discoveries in one video! Big, if true.
| arecurrence wrote:
| In the lk99 subreddit, a higher res video was posted
| https://www.douyin.com/video/7263715495256378659
| PUSH_AX wrote:
| Forgive me, I know little about these things, but what's the
| relationship between this phenomenon and the quantum locking seen
| in other super conducting magnets, this looks as described as
| "pinned", what would allow it to behave like the famous video of
| the magnets levitating around that circular track:
| https://youtu.be/Ws6AAhTw7RA
| marcosdumay wrote:
| Superconductors will resist moving at any direction where the
| magnetic flux gets weaker, stronger, or changes direction.
| That's why they get described as "pinned".
|
| Other diamagnets do that too, but in a decaying way that allows
| for movement. They usually rotate or move slowly sideways.
|
| No other kind of magnetism show similar behavior. They either
| attract or repel all the way in.
| incrudible wrote:
| The most likely explanation: This is a speck of dirt on a string
| filmed as an attempt to manipulate the prediction markets.
| progrus wrote:
| [flagged]
| Zetice wrote:
| As revolutionary as this stuff is, it fits within our current
| understanding of the universe, or maybe a tiny bit outside (for
| now).
|
| Intelligent interstellar aliens using unfathomable technology,
| secretly interacting with humans doesn't.
|
| What you're asserting at this point is that all of science as
| we know it is wrong, and everything we've built was just
| incredible, one-in-a-trillion fortune that any of it worked at
| all.
|
| It's like looking at a plane or a helium balloon and deciding
| gravity is wrong.
| Jevon23 wrote:
| >everything we've built was just incredible, one-in-a-
| trillion fortune that any of it worked at all.
|
| That's not how revision in science works.
|
| We know that Newtonian mechanics was wrong and incomplete,
| but at the same time, it didn't work by "luck" either.
| Zetice wrote:
| That's exactly how revision in science works; incomplete is
| wildly different from "wrong", and most of our
| understanding of science would need to be fully wrong for
| aliens to do what is claimed they can do, to the point
| where we would have needed to get impossibly lucky in order
| to have built the things we have.
| Jevon23 wrote:
| Why would, say, FTL travel being possible imply that we
| needed to be "impossibly lucky" to build the things we
| have?
|
| I'm not a physicist, but I am mathematically literate, so
| please feel free to direct me to technical sources.
| Zetice wrote:
| Because if reality works in a way that lets little green
| men fly ships across galaxies and secretly hang out with
| world leaders, then we're incredibly wrong about how the
| universe works.
|
| And the problem with just being okay with our wrongness
| is that it doesn't match up with our ability to predict
| and rely on the science to complete complex engineering
| projects.
|
| Here's a math example: it's like saying 1+1 is sometimes
| actually fleeb. Easy to imagine, but wholly destructive
| to the entire concept of math.
| Jevon23 wrote:
| >And the problem with just being okay with our wrongness
| is that it doesn't match up with our ability to predict
| and rely on the science to complete complex engineering
| projects.
|
| But a theory can be false while still being predictively
| accurate.
|
| Classical mechanics predicts that quantum tunneling
| should be impossible. But as it turns out, quantum
| tunneling is possible. So classical mechanics is false -
| or at least partially false. But classical mechanics is
| still predictively successful in a wide range of
| scenarios. So, a theory can be both false and
| predictively successful.
|
| The most natural way to explain this is to say that
| classical mechanics is an approximation of a deeper, more
| accurate theory. Similarly, our current best theories
| could be approximations of as yet unknown theories -
| theories that allow for certain phenomena that are
| currently thought to be impossible.
| Zetice wrote:
| Around the margins yes, but directionally no, a theory
| isn't this kind of wrong.
|
| There is likely an LK-99 sized gap in scientific
| knowledge, there is not likely an "aliens land on earth
| and want to hang out" sized gap.
| progrus wrote:
| Yes, and I meant to imply that the alien thing is a hoax, but
| the UFOs are real tech. Obviously. Come on!
| gpderetta wrote:
| Please. Aliens are only a cover. It is well known that the
| pentagon has had a supercomputer that reached superintelligence
| decades ago and has used to slowly tickle advanced technology
| to the masses.
| rowanG077 wrote:
| Don't kid yourself. This is only another smokescreen. In fact
| Abraham Lincoln after his stunt as a vampire hunter was able
| to seal god. They know use gods body to slowly extract
| secrets of the universe.
| progrus wrote:
| Bullshit on both. It's just a bunch of corrupt intelligence
| folks running a psyop.
| mcpackieh wrote:
| Even a breakaway civilization of ancient Atlaneans living under
| Antarctica makes more sense than aliens. Do yourself a favor
| and look up how far away other stars are, consider how many
| times astronomers have looked into space and _not_ seen aliens,
| and then ask yourself why aliens would be so good at cloaking
| themselves in space but would _ostensibly_ let themselves be
| seen on Earth itself.
|
| Spoilers: it's not Atlanteans either, it's just a big tangle of
| hoaxes and self-delusion from people who _want to believe._
| progrus wrote:
| The aliens are a hoax! Come on! How is everyone so gullible
| that _that_ is how you interpret me?
| Jevon23 wrote:
| >Do yourself a favor and look up how far away other stars
| are, consider how many times astronomers have looked into
| space and not seen aliens
|
| Exoplanets weren't confirmed to exist until 1992. Just
| sayin'.
| rvnx wrote:
| And our goggles to see far away aren't that great. We
| barely know anything about the surface of these planets.
|
| The main argument in favour of the non-existence of aliens
| are religious books.
| wredue wrote:
| We don't need to actually see the surface of a planet to
| know whether or not that planet harbours life capable of
| space travel depending how far away the planet is.
|
| Unless they took a completely different, or radically
| faster pathway to interstellar travel.
| rvnx wrote:
| https://www.freethink.com/wp-
| content/uploads/2022/09/image.p...
|
| These are pictures of exoplanets made in 2022.
|
| I doubt we really know what is going there.
|
| The best we can do is to guess the chemistry of the
| atmosphere and assume that all forms of lives require the
| same setup as on Earth.
| mcpackieh wrote:
| >The main argument in favour of the non-existence of
| aliens are religious books.
|
| Not in the slightest, that's the worst strawman against
| it (and for the record, I am an atheist, so drop this
| line of argument now before I'm forced to counter-insult
| you.) Try the Rare Earth Hypothesis. There are only 10^11
| stars in the Milky Way galaxy, you don't need to stack up
| many terms in a "Drake equation" to push the result to
| near zero in the Milky Way. The Rare Earth Hypothesis is
| consistent with all empirical observations thusfar.
|
| Furthermore, even if there were other intelligence
| species like us in our Galaxy, they would be incapable of
| reaching us just as we are incapable of reaching them. To
| believe these aliens are visiting Earth you need to
| explain why you can't see them _anywhere_ except
| ostensibly in deserts above American military facilities
| and installations for testing secret aircraft.
| Jevon23 wrote:
| >To believe these aliens are visiting Earth you need to
| explain why you can't see them anywhere except ostensibly
| in deserts above American military facilities and
| installations for testing secret aircraft.
|
| FWIW, I think this is a much stronger argument against
| the existence of aliens than "they don't fit with our
| current understanding of physics (which is known to be
| incomplete anyway)".
| progrus wrote:
| Yes, duh, the aliens are fake. Everything other than the craft
| is a hoax!
|
| I said this was like pulling teeth. Sheesh.
| BasedAnon wrote:
| [flagged]
| progrus wrote:
| Yes, yes, this person gets it. Thank you.
| ImPostingOnHN wrote:
| the actual room temperature superconductor was adrenochrome
| the whole time!
| BasedAnon wrote:
| adrenochrome? chrome? metal? you know what else is a metal?
| lead!
|
| lead apatite? appetite? hunger? hungry for... metal????
|
| i think you've cracked it
| Waterluvian wrote:
| I'd rather evoke "alchemy" if we're going to reach for the non-
| scientific magic explanations.
| progrus wrote:
| It's not magic, it's a psyop, the aliens are fake, and y'all
| are gullible fools.
| Waterluvian wrote:
| That's just magic by another name. You believe in magic to
| assuage your fears and help with a world that can feel too
| nuanced and complex. Simple answers soothe. That's
| something humans have been doing for a long, long time. If
| it helps, great!
| progrus wrote:
| https://en.m.wikipedia.org/wiki/Psychological_operations_
| (Un...
| sph wrote:
| At least in the alchemy camp we have minds like Isaac Newton.
|
| On the UFO side it's mostly hucksters and numpties commenting
| "wake up sheeple, you can see it's CGI" on ISS live stream
| videos.
| krapp wrote:
| Come on. Grusch's mom says he's a nice boy so obviously
| aliens are real.
| progrus wrote:
| Grusch is likely just an asset being manipulated. This
| guy might be involved in pushing the psyop:
|
| https://www.christophermellon.net/
| rvnx wrote:
| In the meantime there is no irrefutable proof
| [deleted]
| sohex wrote:
| [Citation needed] - What linked patent? It seems incredibly
| rude to me to dismiss decades of dedicated research this way.
| This is a human achievement, it's not right to try to take that
| away from the people who put so much work into it.
| 7thzero wrote:
| I was curious and did a patent search. This may be it:
|
| https://patents.google.com/patent/US20190348597A1/en
| (Piezoelectricity-induced High Temperature Superconductor)
| progrus wrote:
| Yeah this is referred to in the LK99 paper.
| sohex wrote:
| Where? I don't see a reference to it in either of the
| initial two papers or in the Korean journal paper.
| progrus wrote:
| [flagged]
| BasedAnon wrote:
| is it possible in theory that flux-pinning could occur without
| actually causing superconductivity? because LK-99 seems to be
| decoupling alot of properties we thought were coupled if I'm
| understanding correctly?
| jacquesm wrote:
| That would require 'new physics'. I think most of the weirdness
| stems from either (1) sample impurity, (2) an extreme form of
| that where the active bits are really tiny in a large chunk of
| inert stuff or stuff with its own electromagnetic properties or
| (3) being mistaken about it being a superconductor in the first
| place.
| traverseda wrote:
| It could be an entirely new hitherto unobserved phenomena, but
| that seems pretty unlikely. I think that having a bunch of tiny
| superconductors chunks separated by a regular conductor would
| explain a lot.
| m3kw9 wrote:
| It didn't pin, it bounces, if it was flux pinning it would not
| bounce when you push it down.
| jack_riminton wrote:
| Flux pinning doesn't mean it can withstand all forces it just
| means it will return to where it was
| traverseda wrote:
| What about those Flux pinned maglev "trains" you see on
| YouTube?
| mcpackieh wrote:
| What do you mean "what about?" them? Can you post a video
| of any of those that don't jiggle when poked?
| XorNot wrote:
| The idea of those (i.e. like this
| https://www.youtube.com/watch?v=AWojYBhvfjM&vl=en) is that
| they're an example of equi-potential behavior.
|
| The superconductor can move because it's staying at a
| consistent height.
|
| The video linked is also pretty good at showing similar
| behaviors to the sample of LK99 we see claimed in the
| video: the superconductor can wobble, shake and does return
| to it's original position (or tries to) - but it's got a
| lot more mass.
| jacquesm wrote:
| And when you change the mass of the train the height of
| levitation changes.
| traverseda wrote:
| Yeah, it's jumping back to a fixed position which isn't how I
| thought the Meissner effect worked. Since this seems to be
| posted by someone reputable though it's weird they missed that.
| bobbylarrybobby wrote:
| Flux pinning is distinct from the Meissner effect
| kochie wrote:
| That's not true. Here's a video from a few years ago [showing a
| superconductor flux
| pinning](https://www.youtube.com/watch?v=OSojjjvRCR0). You can
| see from the video it's moving around. Also if it didn't move
| when you applied a force to it that would be quite the
| immovable object.
| cbolton wrote:
| Another one that looks quite like the behavior shown here:
| https://www.youtube.com/watch?v=R2Hy6F_8n58
| m3kw9 wrote:
| Ok my bad
| [deleted]
| bhaney wrote:
| [flagged]
| satvikpendem wrote:
| I've seen people saying this on Twitter and elsewhere, where
| are we back from?
| sph wrote:
| Back to annoy us with inane Twitterisms, I reckon.
| alchemist1e9 wrote:
| It is kinda funny once you get used to it. When there is
| bad news they say "it's so over" and good news "we're so
| back". The emotional rollercoaster on LK-99 is pretty
| intense and these phrases capture that for people. I get it
| at this point.
| kzrdude wrote:
| So it's the same as the Bob Ross memes of "Ruined", then
| :)
| Werewolf255 wrote:
| X-isms
| beowulfey wrote:
| Life on twitter teeters on the edge separating intense
| excitement and horrific despair, and "we are back" means
| we've switched from one side to the other again
| _0ffh wrote:
| It's a split meme that refers to the emotional rollercoaster
| of a prolonged uncertain situation whenever news come in.
|
| Its two parts are "It's so over" when there's bad news and
| "We're so back" when there's good news.
| jacquesm wrote:
| I wished they would keep it on Twitter and elsewhere and not
| bring that crap to HN.
| joquarky wrote:
| While I agree with your sentiment, the phrase "we're back"
| is at least as old as the film (1988) Coming to America,
| probably older.
| amelius wrote:
| Can anyone explain if the specimen was found through rigorous
| research or just sheer luck?
|
| Because it is starting to seem like it's the latter.
| rowanG077 wrote:
| This is a very odd question to me. All research is essentially
| this may or may not work. That's why you test it. In a sense
| finding something cool is a very large part luck.
| sidlls wrote:
| A very large quantity of discoveries in science are a
| combination of "well, that's odd" and the "sheer luck"
| associated with the circumstances producing that statement.
|
| (This isn't a commentary on the truthfulness of the
| superconductor claims.)
| amelius wrote:
| Yes, but that doesn't answer the question ...
| mensetmanusman wrote:
| Yes it does, the answer is both, but with the caveat that
| there were people focused on rolling the dice of luck to
| search for this.
| kijin wrote:
| Does it matter? Even "rigorous" research depends on luck in
| many cases, because there are so many unknowns. Theory helps
| reduce the search space, but there are situations when a brute-
| force attack is the most efficient way to answer the all-
| important question: is this real?
| mytailorisrich wrote:
| Many things were discovered out of luck in the course of
| research.
| mcpackieh wrote:
| Trying lots of stuff for years and years until something works,
| aka rigorous research _and_ sheer luck.
| jacquesm wrote:
| Guided brute force search.
| scarmig wrote:
| There is a combinatorial number of different materials out
| there. They chose a particular small subset of them that they
| predicted might have some interesting properties and, over two
| decades, discovered one that may have those properties.
|
| Most hypotheses are wrong, and even if they turn out right it
| may well be a case of being right for the wrong reasons.
| Regardless, this is top tier research: unglamorous,
| uninstagramable drudgery guided by intellect. Sure, there's
| luck involved, but research always involves luck.
| fossuser wrote:
| No idea if accurate but there was this which is interesting:
| https://news.ycombinator.com/item?id=36996337
|
| > " Specifically they were one of the last believers of long-
| forgotten Russian theory of superconductivity, pioneered by
| Nikolay Bogolyubov. The accepted theory is entirely based on
| Cooper pairs, but this theory suggests that a sufficient
| constraint on electrons may allow superconductivity without
| actual Cooper pairs. This requires carefully positioned point
| defects in the crystalline structure, which contemporary
| scientists consider unlikely and such mode of SC was never
| formally categorized unlike type-I and type-II SC. Professor
| Tong-seek Chair (coedongsig) represented a regret about this
| status quo (in 90s, but still applies today) that this theory
| was largely forgotten without the proper assessment after the
| fall of USSR. It was also a very interesting twist that Iris
| Alexandria, "that Russian catgirl chemist", had an advisor who
| was a physicist-cum-biochemist studied this theory and as a
| result were so familiar with the theory that they were able to
| tell if replications follow the theoretical prediction."
|
| So it might be an old hypothesis brought back?
| overnight5349 wrote:
| Those two options are not mutually exclusive
| keepamovin wrote:
| What I like most about this development is that, suddenly, folks
| with "CEO " or "Founder " in their Twitter bio look uncool, while
| folks with "<hardscience>" in their twitter bio are uber cool.
|
| Note to pedants: yes yes, the Venn diagram has an intersection.
| naillo wrote:
| People with <hardscience> in their bio have always been cooler
| fHr wrote:
| facts
| malermeister wrote:
| Folks with CEO or "Founder" in their bio have always looked
| uncool imo.
| jacquesm wrote:
| I meet on average a hundred of those every year and while
| some of them are seriously uncool the majority is actually
| very impressive.
| malermeister wrote:
| They can be impressive and there's nothing wrong with being
| a founder or a CEO (I'm one, too!).
|
| Putting it into one's bio is what makes it... cringe, as
| the kids say.
| jacquesm wrote:
| It's something pretty standard for funded start-ups
| because the rest of the ecosystem that they operate in
| expects it. If it is two guys in an attic it's cringe
| (see my 'you are not the CEO article') but if you have
| picked up some funding and employ 20 people I totally get
| why you would do that.
| mmmpop wrote:
| [dead]
| shawabawa3 wrote:
| This is basically proof of room temperature superconductivity
| correct? (Of course assuming it isn't a hoax)
| pera wrote:
| This is an hoax and it's sad to see people like Sabine
| Hossenfelder falling for it so easily:
|
| - video recorder in a kitchen or living room
|
| - created by some random tiktok account
|
| - no credentials, no description
|
| - tagged "mysterious"
|
| It's hard to understand how anyone would believe this,
| specially after so many other fakes
| p-o wrote:
| Hoax is quite a strong word where there's been quite a few
| replication attempts with various degrees of success. Like
| others have said, we're not sure what this is, but it almost
| certainly isn't a hoax.
|
| As for this video, well, it's like all the other ones that
| came before it, we'll know more once we have more
| data/videos/replication attempts.
| pera wrote:
| I meant that this video is a hoax. I don't hold any
| opinions regarding LK-99.
| mr_mitm wrote:
| Some of the other videos were at least from some more or
| less reputable sources. This one appears to be anonymous,
| or am I wrong?
| Hakkin wrote:
| The source[0] seems to be the Douyin (TikTok) user Lian
| Dan Shi A Xiang [1], who also posted a different LK-99
| demonstration video[2] a few days ago that shows similar
| results to previous demonstrations by other researchers.
|
| [0] https://www.douyin.com/video/7263715495256378659
|
| [1] https://www.douyin.com/user/MS4wLjABAAAAJaTuSBArw0c6b
| K0eI9T1...
|
| [2] https://www.douyin.com/video/7262676385154583860
| mr_mitm wrote:
| Yes but what research institute are they affiliated with?
| For all I know this is an pseudonymous TikTok user who is
| good at faking videos. Why should I take this for
| anything but complete fiction?
| Hakkin wrote:
| Certainly not making any claims of the legitimacy, just
| providing the original sources. There doesn't seem to be
| any attribution besides the anonymous account.
|
| The Chinese subtitles in the first demonstration claim
| "further efforts will be made to reduce impurities", then
| the subsequent video claims "technical details will be
| published once they are properly organized and
| documented".
| fallingknife wrote:
| I see no indication that it was filmed in a kitchen or living
| room.
| fnordpiglet wrote:
| In fact I see some serious lab quality glassware in the
| background. But posting without its provenance is a weird
| for sure.
|
| IMO there's an awful lot of amateur / informal attempts
| that are promising enough that, while not convincing, are
| inspiring of hope. But I do wonder how much is fake. But
| more than a few seem to be clearly not fake, such as the
| work Varda is posting.
| oxfordmale wrote:
| No, it is not yet proof of superconductivity. It also requires
| measurements of the electric resistance as function of the
| temperature.
|
| For now LK-99 is an material that displays some of the
| superconducting properties at room temperature.
| kzrdude wrote:
| Let's use the word evidence and not proof for each part of the
| puzzle
| dmitrybrant wrote:
| Assuming everything in the video is real, the only remaining
| question is: what is the actual temperature of that sample?
|
| If all of this checks out, then it's a new era.
| Enginerrrd wrote:
| It looks convincing to my naive eyes, but how would you
| differentiate between this and diamagnetic levitation of
| something like pyrolitic graphite?
| cthalupa wrote:
| https://twitter.com/Andercot/status/1687748594563268608
| seems to indicate that simply diamagnetic levitation cannot
| create the level of stability shown in this video.
| Enginerrrd wrote:
| I don't think that's right. Diamagnetic levitation is one
| of the ways you can get around Earshaw's theorem.
|
| Funny enough this is a quote taken directly from the
| wikipedia article that Andercot linked, in the
| "loopholes" section:
|
| >Earnshaw's theorem has no exceptions for non-moving
| permanent ferromagnets. However, Earnshaw's theorem does
| not necessarily apply to moving ferromagnets,[4] certain
| electromagnetic systems, pseudo-levitation and
| diamagnetic materials. These can thus seem to be
| exceptions, though in fact they exploit the constraints
| of the theorem.
|
| ...
|
| >Diamagnetic materials are excepted because they exhibit
| only repulsion against the magnetic field, whereas the
| theorem requires materials that have both repulsion and
| attraction. An example of this is the famous levitating
| frog (see Diamagnetism).
| sudosysgen wrote:
| How can a diamagnet be stable on top of a single dipole?
| Earnshaw's criterion being invalid just means that there
| is at least one static arrangement of magnetic dipoles
| that lead to stability. However, if you have a point-like
| diamagnet resting on top of a single dipole it can't
| possibly be stable because there is no point at which it
| will have zero net force and stable higher-order
| derivatives. You need something like a bowl-shaped
| magnetic field arrangement for it to stay in a single
| point, or have the diamagnet itself be shaped something
| like a bowl over the field.
| Enginerrrd wrote:
| Yeah you bring up a good point... I don't think it can.
|
| But you CAN do it with concentric rings of magnets. Such
| magnets seem common for this exact demonstration
| actually. It doesn't look like one of those in the video
| though.
| cthalupa wrote:
| Sure enough. Which, well, makes sense, since
| superconductors are "perfect" diamagnets, so them being
| able to do it seems to necessitate that the greater class
| of diamagnets on the whole can too.
|
| The only examples I can find of stable non-superconductor
| diamagnets involved 4+ magnet arrays, though, or
| multipole magnets, e.g.
| https://phys.org/news/2014-08-diamagnetic-levitation-
| pyrolit... and not dipole configurations like this video
| seems to show.
| [deleted]
| Arn_Thor wrote:
| No, the video contains no information about its conductivity.
| jiggawatts wrote:
| Such tiny samples warm up to room temperature very quickly,
| on the order of a few seconds. In my experience, it's not
| possible to make such small pieces of YBCO superconductor
| levitate, they warm up too fast.
| topynate wrote:
| No frost on the sample either. The only way I can think of
| to fake this in camera is to make the "sample" out of a
| strong magnet, and make the "magnet" a hollow shell
| concealing a chilled piece of YBCO!
| incrudible wrote:
| You would be surprised what can be achieved with bit of
| nylon string and an appropriate camera setup. If this is
| a most groundbreaking discovery, why waste all that
| screen resolution on the backdrop?
| [deleted]
| kzrdude wrote:
| Nitter: https://nitter.net/Andercot/status/1687740396691185664
| kzrdude wrote:
| Alternative video link here, but it's in chinese so no idea if
| it gives any more information about the source:
| https://news.ycombinator.com/item?id=37010498
| [deleted]
| yorwba wrote:
| The video is watermarked Lian Dan Shi A Xiang (Alchemist
| Axiang), which is also the username of the Douyin video, so I
| think that's the closest to the original source we can get.
| (The tweet claims Bilibili as the source, but it was
| apparently a live stream and Lian Dan Shi A Xiang 's Bilibili
| account currently only has a previous video without full
| levitation. https://bilibili.com/video/BV1sM4y1H7MX )
| Kiro wrote:
| OT but why do I need to press "enable this playback" and reload
| the page to view the clip? What does it do?
| meibo wrote:
| Because they want to avoid sending your IP to Twitter if you
| aren't going to watch the video, and the way to do that
| without JS is to only render the video embed if you actually
| request it.
| [deleted]
| trashburger wrote:
| HLS is a way to serve a video in chunks over HTTP. It's how
| livestreams are implemented in most places. Twitter serves
| videos in HLS chunks, but Nitter doesn't want to proxy it to
| you because videos take a lot of bandwidth. In order to let
| you choose whether you want to connect to Twitter servers, it
| first asks you whether you want to enable playback.
| 38 wrote:
| non crap link:
|
| http://farside.link/twitter.com/andercot/status/168774039669...
| semajian wrote:
| It's hard to imagine how this could be faked short of digital
| manipulation, and it seems implausible that it would be a known
| high TC superconductor because it would warm up too fast. Absent
| the former explantation, I'm starting to believe this is real.
| Also, it's not like all the author's are unknown hacks. Hyun Tak
| Kim has about 10k citations (Google scholar, which sometimes
| combines people who have the same name though) and authored a
| paper in scientific reports which got L&K interested in
| collaborating with him. The guy seems to know superconductivity
| so I'm feeling rather optimistic about this.
| thecopy wrote:
| According to this video:
| https://twitter.com/xmal/status/1300754522218913799 it is
| possible to have stable levitation using a copper plate below
| the magnet.
|
| OP's video has two stacked metal objects - could the lower one
| possibly contain copper?
| raziel2701 wrote:
| The object that is rotating is a magnet. It's not what we're
| seeing with the flake which appears to be flux pinned.
|
| If this is fake, it's a very well-done fake. I'm feeling 60%
| sure that LK-99 is RT superconductor at this point. It has
| theoretical support now since last weekend.
| yorwba wrote:
| That one is clearly rotating. Magnetic levitation with a
| rotating field is not too difficult (you can get levitating
| flower pots as cheap novelty toys) but the sample in the new
| video appears fully static.
|
| Edit: relevant Wikipedia: https://en.wikipedia.org/wiki/Spin-
| stabilized_magnetic_levit...
| nyanpasu64 wrote:
| The video in the reply
| (https://twitter.com/xmal/status/1300794329347260417) seems
| to show levitation even when the magnet isn't rotating?
| jacquesm wrote:
| They're stacked to increase the field density.
| Qem wrote:
| > Hyun Tak Kim has about 10k citations (Google scholar, which
| sometimes combines people who have the same name though) and
| authored a paper in scientific reports which got L&K interested
| in collaborating with him.
|
| It appears he was a latecomer to the project, mostly borrowing
| his reputation to the trio of anonymous, non anglosphere native
| original authors.
| light_hue_1 wrote:
| Let's be less cynical. Nothing to do with borrowing
| reputation.
|
| The original authors have something. They don't have the
| expertise in condensed matter physics to really know what.
| They don't know how to report results and what results would
| be conclusive. Their work is simply not convincing, and if
| they were experts they would also not be convinced.
|
| That's why they brought in another collaborator who is an
| expert. But because the paper was released early it's clearly
| a mess. You can see the big quality improvement though just
| between the two drafts.
| Qem wrote:
| It's not cynism. The disagreement about authorship
| apparently was motivated by someone in the original team
| being pushed aside to open a slot for the well connected
| "10k citations" guy. It's a old problem academia still
| fails to address. See:
|
| https://journals.plos.org/plosbiology/article?id=10.1371/jo
| u...
|
| https://en.m.wikipedia.org/wiki/Neo-colonial_science
| Facemelters wrote:
| No one knows if this version of events is true
| Qem wrote:
| Indeed. But if further investigation reveals the
| situation to be what it appears to be, this would follow
| a long list of similar occurrences, the likes of Cesar
| Lattes and Jocelyn Bell.
| stavros wrote:
| > It's hard to imagine how this could be faked short of digital
| manipulation
|
| So, it's easy to imagine how this could be faked.
| marcosdumay wrote:
| I guess the point is, it can be a fabrication, it can be
| something very important, and it can't really be anything in
| between.
| ynniv wrote:
| It can easily be faked, using a technique that would destroy
| the poster's career. It's one thing to not do something to
| the letter, and another to commit blatant fraud. Most career
| academics would not burn their career for the lulz.
| stavros wrote:
| It's an anonymous video.
| ncr100 wrote:
| Alternatively, https://en.wikipedia.org/wiki/Pyrolytic_carbon
| is discussed in the Twitter thread by the OP as a possible
| explanation of "not superconductivity" . . .
| cthalupa wrote:
| Not an expert, but my understanding is that magnet
| configuration could not create a stable levitation for
| pyrolytic graphite - you need an array of magnets, e.g.
| https://arxiv.org/ftp/arxiv/papers/1010/1010.5761.pdf
|
| Doing a quick sanity check on youtube videos, every example
| I can find of it levitating involves use of magnet arrays
| as well.
| semajian wrote:
| Well, yes
| stavros wrote:
| I'm holding a small basket until one of the reputable labs
| reproduces this. Anonymous videos on Twitter are a bit too
| anonymous for me.
| pera wrote:
| Seriously? To me this looks like a chip of graphite glued to an
| invisible thread. The way the object moves is not what I would
| expect from magnetism (see second 10 for instance)
| tester457 wrote:
| This video describes quantum locking as strings going through
| a superconductor.
|
| https://youtu.be/8GY4m022tgo?t=957
| mcpackieh wrote:
| How can it _look_ like something that is ostensibly
| invisible? It 's not swinging around like a pendulum, so what
| exactly are you seeing that makes you think it _looks_ like
| an _invisible_ string?
| Cushman wrote:
| What accounts for the smooth "settling" into place after
| the last touch around 10s?
|
| I have no idea what I'm talking about, but in other flux
| pinning demonstrations the sample seems to oscillate around
| the fixed point. That smooth settling looks like some sort
| of damping, like maybe a force that increases with
| distance, like maybe spring tension.
|
| (Of course, "we have no idea" is an acceptable answer if
| that turns out to be the case.)
| mcpackieh wrote:
| Air resistance seems like a reasonable explanation for
| the dampening. Furthermore if it's not pure and only
| partially superconducting, the dampening could be due to
| magnetic fields forming eddy currents in the sample.
|
| > _(Of course, "we have no idea" is an acceptable answer
| if that turns out to be the case.)_
|
| Of course.
| Cushman wrote:
| Good hypotheses both! "We've never been able to pin
| something this size before" covers a lot of wiggle room.
| So to speak.
|
| (FWIW I'm thrilled about the _possibility_ of a rtrp drop
| this year, and I have to assume 'pera is as well. But
| this video doesn't look _just_ like flux pinning we've
| seen before. It's visibly a little different in a way
| that wants explanation. I wouldn't come out the gate
| calling it a hoax, but I'd feel better about not doing
| that if the basis for skepticism were at least
| acknowledged.)
| pera wrote:
| The thread is horizontally positioned, left to right, not
| vertically.
| gabesullice wrote:
| Finding a thread that small would be a feat of its own. I
| wonder if your eyes might be getting tricked by the
| watermark?
| mcpackieh wrote:
| But you haven't explained how it _looks_ like that. It
| _could_ be that, but it _looks_ like it 's floating. What
| is it about _the appearance of this thing_ which has you
| believing there is a string?
| incrudible wrote:
| If there is a magician on the stage, you can safely
| presume there is no actual magic involved, even though
| you do not know how exactly the trick works.
|
| For actual flux pinning, the first thing you would do is
| show what happens if you put the thing upside down. It
| should stick. Even if it does not, you would show that
| _it does not_.
| nullc wrote:
| This is what a pinned superconductor looks like. Here is a
| video I made of some YCBO over a small magnet:
| https://nt4tn.net/random/superconductor.mp4 you can see it
| settle back back when I move it with tongs (until i push hard
| enough to get it to snap into a new orientation).
|
| If I had a magnet that was much bigger than the
| superconductor it would look even more similar (less
| 'pivoty').
| jacquesm wrote:
| Excellent video, really very nice. I like it how you forced
| the flux pinning by punching a hole in the middle of the
| superconductor, that makes it all much more visible. You
| can practically visualize the fieldlines escaping through
| the middle and becoming an elastic pivot connected to the
| magnet.
| nicpottier wrote:
| Have you watched other videos of flux pinning? This sure
| looks like those to me, it's a weird phenomenon.
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