[HN Gopher] Superconductor news: What's claimed, and how strong ...
___________________________________________________________________
Superconductor news: What's claimed, and how strong the evidence
seems to be
Author : etiam
Score : 1152 points
Date : 2023-07-26 17:46 UTC (1 days ago)
(HTM) web link (www.science.org)
(TXT) w3m dump (www.science.org)
| carabiner wrote:
| Researcher on reddit thinks it's probably spurious measurement
| artifacts, not superconductivity:
|
| > I would say they are not faking it, but instead they just don't
| understand what they are looking at. Based on what measurements
| they are doing, as well as how they are doing them, they do not
| have a good understanding of the standard processes to
| characterise a superconductor. Also, based on their
| analysis/discussion, they do not have scientific knowledge of the
| background theory. In review of these two papers, it's terrible
| science, not something malicious (as has been seen before in RT
| superconductivity work...). Even if these claims turn out to be
| true, it's still terrible science, and that's my main criticism.
| Either way, these types of claims are not uncommon, see for
| example this paper from a few years ago which went nowhere.
| https://doi.org/10.48550/arXiv.1807.08572
|
| https://www.reddit.com/r/worldnews/comments/159g2k4/comment/...
| macromaniac wrote:
| He doesn't provide an actual counterargument,he just says he
| doesn't like the data without explaining why.
|
| His earlier comment that graphite can do the same thing is
| untrue afaict. Graphite can repel the magnetic field but it
| would slide off, this is why in diamagnetic experiments
| multiple magnets are used to keep it in place. In the video it
| doesnt seem to be sliding anywhere, so imo the video is not
| showing diamagnetism.
|
| https://sciencecast.org/casts/suc384jly50n
|
| Edit: Actually, now I'm not so sure, it does seem like it's
| held in place by one corner which is always pointing towards
| the outside of the magnet, so maybe it is just diamagnetism. If
| anyone has some pyrolytic carbon and wants to try it out?
|
| Edit2: 99% of YouTube videos on diamagnetism have multiple
| magnets, the only one I could find that has diamagnetism on one
| pole magnets shows it not working:
|
| https://youtu.be/D-tW8_SRW3g
|
| I think it's more than just pyrolytic carbon
| mhh__ wrote:
| Intuition shouldn't be considered harmful.
| whatshisface wrote:
| It is clearly resting on the magnet. I don't know the
| mechanics off the top of my head, but that is enough
| mechanical constraint for a pair of permanent magnets to
| levitate.
| willis936 wrote:
| It isn't. Permanent magnets would be unstable. This would
| have to be a diamagnetic or superconducting material.
| IshKebab wrote:
| It is, depending on how big the contact patch is. But
| does look pretty small in this video and it doesn't
| really behave like a permanent magnet would.
| [deleted]
| sockaddr wrote:
| I'm not convinced it's levitating in the video, imagine a
| magnetic field strong enough to partially lift the fleck
| but also a patch of the fleck contacting the magnet with
| enough friction to keep it from sliding away.
| jeepers6 wrote:
| Superdiamagnetism occurs primarily in superconductors.
|
| Reminder that flux-pinned levitation only occurs when
| superconductors are cooled from above to below their
| critical temperature while in a local magnetic field.
|
| The researchers probably didn't heat up their big sample
| above the critical temperature in air as that could have
| mechanically destroyed it. It was already chipped almost
| in two.
| mitthrowaway2 wrote:
| > Reminder that flux-pinned levitation only occurs when
| superconductors are cooled from above to below their
| critical temperature while in a local magnetic field.
|
| Casual demonstrations of levitating superconductors
| involve first submerging the superconducting material in
| a (non-magnetized) tub of LN2, and then moving it onto a
| magnetic track. For example,
| https://www.youtube.com/watch?v=X5EoUD-BIss
| jeepers6 wrote:
| That's true, surprising to hear that the YBCO SC in that
| video is only 30um think.
| weberer wrote:
| >He doesn't provide an actual counterargument,he just says he
| doesn't like the data without explaining why.
|
| Welcome to Reddit
| FlawedReformer wrote:
| One of the authors explains in this article:
| https://www.newscientist.com/article/2384782-room-
| temperatur...
|
| > However, only one edge of the flat, coin-like material
| fully levitates, while the other seems to stay in contact
| with the magnet. Kim says this is due to the sample being
| imperfect, which means that only some part of it becomes
| superconductive and exhibits the Meissner effect.
| floxy wrote:
| >so maybe it is just diamagnetism.
|
| Superconducting levitation is just due to the perfect
| diamagnetism of the superconductor, right?
|
| https://en.wikipedia.org/wiki/Superdiamagnetism
| hatsunearu wrote:
| https://www.kci.go.kr/kciportal/ci/sereArticleSearch/ciSereA...
|
| This one's in Korean but there are some plots here that I think
| several people said were missing.
| hackernewds wrote:
| The redditors response seem to be generic, where is the counter
| evidence, and proof of their authority?
| throwaw1yyy wrote:
| [flagged]
| hatchling wrote:
| Agreed on reddit being terrible. What is "strong alpha"
| though?
| bhouston wrote:
| It is from finance:
| https://www.investopedia.com/terms/a/alpha.asp
| pnut wrote:
| Possibly they mean people with reliably high signal to
| noise ratio, analogous to the investment term
| https://www.investopedia.com/terms/a/alpha.asp ?
| hatsunearu wrote:
| I'm not a materials scientist but an electronics guy.
|
| > 1b) shows the resistivity at some unknown temperature. They
| are applying current and measuring no potential drop. Just
| what? First, state the temperature, next measure it as a
| function of temperature. At the critical temperature the
| resistance drops to zero. All they have shown is that the
| contact inputting the current is probably disconnected...
|
| this does not pass the sniff test for me. I explained on reddit
| myself why I think it doesn't make sense.
|
| The only way that could work is if they just straight up
| fabricated everything, and in that case all bets are off.
|
| I can't comment about the others since I don't know enough
| about it. Considering 1b) makes no sense with a modicum of
| knowledge, I really doubt the veracity of the rest.
| stu255 wrote:
| You realise two of the authors (Lee and Kim) discovered this
| in 1999 (hence LK-99), and only published this paper after a
| huge fall out within the research team?
|
| This isn't 1 experiment. This is 20 years of research leaking
| because of a fight over credit.
| foven wrote:
| Agreed, this looks bogus. Some suspicious points:
|
| In the first paper, they claim to measure zero resistance (on a
| scale of microvolts), but are very careful not to show full RvT
| curves - in the second paper, we can still see significant
| changes below Tc where they include more complete curves. How
| can the resistance change significantly in the superconducting
| (zero resistance) state? We can actually see significant noise
| in paper 1 fig. 1c in the ohmic state and it even appears to
| behave as an insulator at 0 field (increasing resistance with
| decreasing temperature), but a metal with applied field.
| There's something wrong with the measurement.
|
| 400 K is an odd choice for your superconducting temperature,
| and just so happens to be the top end of what an MPMS system
| can measure so is not completely random. Surely it makes sense
| to measure significantly above this with one of the oven
| attachments, verify these results with collaborators at other
| labs even.
|
| 10 Gauss is an extremely small field to use for a ZFC-FC
| measurement and again if their superconducting Tc is at or
| above 400K they need higher temperature data to show anything
| about the phase transition.
|
| The claim that they have measured the density of states is
| completely unjustified - not even a citation. I don't know how
| you can believe that to be the case.
|
| And in general the presentation both of the data and the paper
| itself is poor - if you just made a groundbreaking discovery
| like this, wouldn't you care?
| zarzavat wrote:
| > if you just made a groundbreaking discovery like this,
| wouldn't you care?
|
| Hell no! If I had made a discovery of similar magnitude I
| would have done exactly what they've done: push out a rough
| preprint ASAP to reserve my Nobel prize, then take a deep
| breath, relax and take my time dotting 'i's and crossing 't's
| for the real paper in Nature.
|
| That doesn't mean they're correct, but there's nothing
| inherently suspicious about the way this has unfolded.
| stu255 wrote:
| Exactly, they have made a very big claim and made it very
| easy to replicate / falsify. It takes a few days to produce
| this stuff.
|
| Their paper is weak on data / results.
|
| This is exactly what you would do if your team genuinely
| believed you had discovered something monumental.
|
| In poker terms they are "all in" and they want to get
| called.
|
| That's why it is so interesting. If they had posted lots of
| extreme results but it needed $10m to replicate then I
| would be thinking "fraud". It would look like a bluff.
| meroes wrote:
| The motivations for fakery are too high.
| foven wrote:
| As I mentioned in my above post, they have really dodgy
| data. Ideally, with something like this, you would have
| collaborators to verify alongside you as joint co-
| authors. I think something people underestimate if how
| easy to replicate samples are - crystal growth is
| difficult, and impurities are important. It is unlikely
| anyone will produce exactly the same sample only
| something close based on the process they've given.
|
| In realistic terms it seems they're grabbing for the
| prestige without the foundation of crossing their ts. Bad
| science like this shouldn't be encouraged. It's likely
| there's not very many groups growing the same material
| system so they have the time to spare. A paper like this
| wouldn't be on the arxiv at all if they were 100% sure
| because they would go straight for the nature publication
| and take the time to do more follow-up papers while they
| can.
|
| Edit: to be clear as well, a lot of people are
| underestimating the time it takes to reproduce a growth
| even with a manuscript telling you how to do it. People
| always leave out steps and oversimplify. There is a lot
| of extra characterization that takes time to double check
| you have the right material that lines up with what they
| have here. Only the direct competitors actually already
| growing this material can do it in a few days.
| peteradio wrote:
| I think the politicking of the situation could explain
| why there was minimal involvement of outside
| collaborators.
| nazgulnarsil wrote:
| excellent point that the noise should raise probability of
| measurement/set-up/equipment issues
| LargeTomato wrote:
| >I would say they are not faking it, but instead they just
| don't understand what they are looking at
|
| What? How do they get funding and lab space if they can't read
| their own measurements? Something is fishy here.
| sanxiyn wrote:
| They in fact could not get funding and the research is funded
| by investment money. They explicitly thank their investors at
| the end.
| tomjakubowski wrote:
| What do you mean? Is it one of the other papers? I see
| this:
|
| _Funding: This research was mainly supported by Quantum
| Energy Research Centre, Inc. and was also partially
| supported by Basic Science Research Program through the
| National Research Foundation of Korea (NRF) funded by the
| Ministry of Education(2019R111A1A01059675) and Young-Wan
| Kwon is supported by a Korea University Grant._
|
| I don't know, either: what's the difference between
| receiving funding for research and taking investment money
| for it? Are you talking about public vs private funding?
| TheBigSalad wrote:
| What is finding?
| mikeyouse wrote:
| From what I understand, this group wasn't actually funded to
| look for superconductors but instead for materials to aid in
| quantum nanoscience - so the claim isn't that they don't know
| how to read their instruments but rather that they aren't
| well-versed enough in superconductor research to
| appropriately design/test for the phenomenon.
| aqme28 wrote:
| I'm curious how those page 3 I/V figures are just spurious
| measurement artifacts. They seem very clearly to be evidence of
| high temp superconductivity
| _0ffh wrote:
| >> they do not have scientific knowledge of the background
| theory
|
| One of the co-authors of the 6-author-paper, Hyun-Tak Kim, is
| at least answering questions about superconductor theory on
| Quora starting five years ago, whatever that counts for.
|
| He states there "I am studying the MIT mechanism in strongly
| correlated systems, the high-Tc mechanism in cuprate
| superconductors, the MIT devices, and quantum transistors.".
|
| https://www.quora.com/profile/Hyun-Tak-Kim?share=1
| fluidcruft wrote:
| Another interesting comment by that redditor
| https://www.reddit.com/r/technology/comments/159jojs/comment...
| [deleted]
| WaffleIronMaker wrote:
| Another interesting analysis from that post:
|
| > So, to clarify for my nonexpert brain, if this were a
| superconductor and their measurements were accurate:
|
| > Fig 5 means the sample must be completely pure to be a
| superconductor
|
| > The rest of the paper indicates the sample must have
| impurities.
|
| > So it's pretty safe to say that either it's not a
| superconductor or their measurements are wrong (or most likely
| both). Since they never got it to the critical temperature and
| showed the full Meissner effect, if the measurements are wrong
| it's fair to say they don't have evidence for superconductivity
| anyway, just diamagnetism, which isn't really that big a deal
|
| https://www.reddit.com/r/worldnews/comments/159g2k4/comment/...
| btilly wrote:
| The paper that I'm seeing only has 4 figures.
|
| In any case, the need for impurities would not itself
| surprise. Having controlled amounts of impurities is called
| "doping", it is well-known from studying semiconductors and
| other high temperature superconductors that the amount of
| doping can have a huge impact on a substance's properties.
|
| See https://physicsworld.com/a/the-ups-and-downs-of-doping/
| for verification of this point.
| tux3 wrote:
| This is the second, slightly cleaner paper with more
| figures:
| https://arxiv.org/ftp/arxiv/papers/2307/2307.12037.pdf
| tigershark wrote:
| As far as I understand there is no real explanation for the
| measurements and the video demonstrating the Meissner effect
| apart from faking it. The Reddit thread that you posted alleges
| that they were faking the video by super-cooling a non-room
| temperature superconductor for example. Do you have proof that
| they actually are so crazy to fake a certain Nobel prize when
| their research can be verified in a short time? From my side I
| will wait a week or two for the reproduction from other labs.
| You can continue spreading your reddit-based opinions until
| then.
| TillE wrote:
| All the amateur debunking just smells like the usual
| confidently incorrect contrarianism, which is always popular
| on sites like Reddit.
|
| There's just way too much going on for this to be a sloppy
| mistake. It's either real or a fraud, and in both cases the
| alleged errors aren't particularly important.
| Freedom2 wrote:
| > sites like Reddit.
|
| I'm glad this site doesn't partake in incorrect
| contrarianism.
| honkycat wrote:
| I've been saying for years we are one "future technology" away
| from savings our asses from our world collapsing.
|
| Here is hoping this is that breakthrough.
| Evidlo wrote:
| Maybe post-scarcity countries will have more time to focus on
| fighting for land and less need for maintaining good relations
| with others.
| keenmaster wrote:
| With tons of cheap energy, you can make better use of the
| land you have. The entirety of humanity can technically fit
| in Southern California. I'm imagining a swarm of construction
| robots running on dirt cheap power, excavating land and
| building beautiful AI-designed mid-rise apartments in all
| directions. Scarcity, what's that? And once we have bonkers
| amounts of power, like from fusion, we can trivially extend
| cities out into the sea by adding to the landmass (though
| this won't account for a majority of the scarcity reducing
| effect).
| MrPatan wrote:
| The moment they push the sample and it "turns and snaps" into the
| magnet in this video:
|
| https://sciencecast.org/casts/suc384jly50n
|
| makes it look like a diamagnetically levitating piece of graphite
| moving over multiple magnets in this video:
|
| https://www.youtube.com/watch?v=D-tW8_SRW3g
|
| Why am I wrong? I want to believe!
| Tade0 wrote:
| My suspicion as well. If in the original video the researcher
| is holding a Neodymium magnet, then at this size it already has
| lethal magnetic power - or at least enough to make one lose
| fingers with improper handling.
| Vox_Leone wrote:
| A passing thought: with [post pandemic] AI and superconductivity
| breakthroughs [case verified], 2023 turned out to be a hell of a
| year. Will be remembered.
| The_Double wrote:
| The strangest thing to me is that apparently this material has
| been developed years ago, the video of a piece floating was
| uploaded 3 months ago, and apparently it's easy to produce more
| samples, but the papers still reads like they have been thrown
| together in less than a week. (English might not be their first
| language, but the presentation of the figures is also poor) And
| it also seems like they haven't spent that time by doing high
| quality experiments. Surely if you have found a magic material
| that can change the world you would spend more effort than this
| on doing experiments and publishing a good paper as soon as
| possible.
|
| The low quality video and poorly presented graphs are reminiscent
| of Victor Ninov's fraud.
| jahnu wrote:
| I read somewhere once that deliberately poor quality graphs are
| sometimes used so that readers cannot extract the precise
| values from them. This could be to obscure fake or real data.
| tomtom1337 wrote:
| This is true, but from personal experience, academics are
| terrible at including high quality images. My colleague would
| screenshot an image from some visualisation software and
| paste it in to her paper in MS Word. Then that image would
| get copied or screenshotted into a different word document,
| and so on, and the quality would deteriorate.
| earthboundkid wrote:
| My wife is an academic and I often see her screenshoting to
| move an image from one document to another. Seems like a UI
| failure that the system can't detect this use case and move
| high quality backing images through the clipboard.
| jimkoen wrote:
| MacOS went full circle here at least with regards to
| text: In the new MacOS versions, if you screenshot text
| there's automatic OCR, so when you receive a screenshot
| of some text, you can copy it again!
|
| It's non-trivial to implement that for something like
| SVG's, but if UI developers had anticipated this use
| case, we might have gotten a remedy with the introduction
| of raster graphics.
| hackeraccount wrote:
| It seems weird because it's a big leap but big leaps do happen.
|
| If it is a misrepresentation I'd be curious about the back
| story. I mean, even if it's not been knowingly done it will
| presumably seriously hurt the careers of the people involved;
| if it is knowingly I assume it will be "find a job in another
| field" kind of thing.
|
| How could you suspect it wouldn't come out if it's knowingly?
| If un-knowingly how could you make an amazing claim like this
| without being absolutely sure of what's going on? If it's a
| "rush to publish" type thing - why wouldn't you make a big
| point of that in the paper (i.e. load it with caveats to the
| brim)? Plus this comment makes it sounds like it's been sat on
| for at least what seems to me like a fair amount of time.
|
| All the options seem implausible but at the end of the day one
| of them must be the case. For the sake of everyone I'm pulling
| that it is what it says on the tin.
| archepyx wrote:
| Another comment from a well informed source on the topic:
| https://nitter.net/condensed_the/status/1684255515944034304
|
| Also, on the sentences in the manuscripts trying to explain the
| effect: I think that is wild guess at best. The measurement
| results done in the manuscripts probably can be taken at at face
| value (at least until there is a reproduction). Whether they
| really indicate superconductivity or something else that looks
| like it in some of the aspects is then a different question.
| thepasswordis wrote:
| It's probably better to link to the original, not this mirror:
| https://twitter.com/condensed_the/status/1684255515944034304
| MikeBVaughn wrote:
| The replies don't load for me in this one.
| cmrdporcupine wrote:
| Twitter is not a publicly available resource, not part of the
| open web: Its URLs are semi-private and require an account to
| fully read and they should not be posted here on HN.
|
| For almost two weeks they were fully locked, and now one can
| only see the original post and not the thread, and all
| browsing is locked out.
| diabolo96 wrote:
| Nitter is an alternative front-end that allow you to view the
| tweet and the response while Twitter only only to view the
| attached tweet only. So in fact , it's better that he used
| nitter rather than the "original"
| floxy wrote:
| Lots of people are saying there should be a quick turnaround time
| here for trying the replication. I wonder how much it would cost
| to try and replicate this, in materials, labor costs, and vacuum
| furnace time/costs. My naive thought is that that labs in general
| aren't just going to drop everything to try an replicate every
| instance of someone declaring they've discovered room temperature
| superconductivity. Seems more like a "there's a lull in paying
| work, so hey, why don't some of you junior technicians try this
| out" thing? Anyone have insight into this? I suppose a university
| lab might have more leeway here to try out spur of the moment
| experiments? Maybe this is a "I'm personally interested in this
| and I'll work in the evenings to test it out, instead of on
| company/university time"? Or are the authors high profile enough
| in the community that it meets a certain threshold of credibility
| that it seems more worthwhile than the average?
| overnight5349 wrote:
| The synthesis outlined in the paper takes about 90 hours, but
| basically all of it is just waiting for the material to bake in
| a furnace.
|
| I'd expect some lab out there to report a result by the end of
| the week. The synthesis really is super simple, just grinding
| powders together and baking in a furnace. Granted, the final
| product has to be baked under vacuum, but that's not super
| difficult to achieve. The authors sealed the material in a
| quartz tube and baked in a standard furnace.
| nharada wrote:
| Under a week of work to publish potentially the highest impact
| paper of your PhD (especially if you're first)? I'm guessing
| most students would take that chance.
| soligern wrote:
| I'm sure this is on Applied Science's (a YouTube channel)
| radar. He recently went on a deep dive on making YBCO
| superconductors so it's right up his alley.
| pzber wrote:
| Would love to see Ben Krasnow from Applied Science try to
| replicate this!
| jeepers6 wrote:
| https://nitter.net/BenKrasnow/status/1684431462643437569#m
| 7373737373 wrote:
| A livestream of this would be awesome
| BurningFrog wrote:
| Just testing the samples already made in an independent
| laboratory would be replication enough!
| refulgentis wrote:
| Not much, see article (~1 day), or article + thread from
| yesterday. https://news.ycombinator.com/item?id=36864624
|
| I don't think, at least generally, work is as rigid as
| indicated. At least at white collar jobs, and especially a
| research lab, and most especially a university research lab.
| floxy wrote:
| $10, $100, $1,000? 1 hour, 10 hours of labor?
| marcosdumay wrote:
| If you have the equipment, some $100s on consumables, some
| 10 hours of labor, and some 60 hours of waiting.
| abibibo wrote:
| From what I recall of the original paper, 1-2 hours of actual
| labor with equipment and reagents many labs already have on
| hand--although it required 24-48hours in the furnace at each
| step which is the only reason for the delay and why the article
| author mentions we should see results tomorrow. So, trivial
| enough most people in similar labs already spent more time
| discussing the implications than actual labor/investment to
| replicate.
| yreg wrote:
| If it really is as easy as you say then surely every YouTuber
| with a metal furnace dropped everything to make that 100M
| view video.
| willis936 wrote:
| I'm hoping they are. I want to watch them this weekend.
| yreg wrote:
| Finally found someone who's liveblogging it:
| https://nitter.net/andrewmccalip
| nneonneo wrote:
| Fleischmann and Pons' famous cold fusion result was announced
| on March 23 1989 and a spate of replication attempts followed
| in the ensuing weeks; by April 30 1989, the NYT ran an article
| calling cold fusion dead due to the large number of reported
| negative reproduction attempts.
|
| Scientists can move far quicker than you expect, and a positive
| or negative replication of this superconductor claim should be
| a very easy publication to grab. It would definitely be worth
| alloting a few weeks of grad student time to replicating this
| ASAP to get that publication.
| m463 wrote:
| The fact that there are other (competing?) scientists doing
| superconductor research suggests there will be organized
| attempts to verify it.
|
| That said, I remember reading about shockley having ideas
| about the transistor that he only fessed up to as his other
| more open collaborators started understanding the phenomenon.
| scarmig wrote:
| It's a reasonable enough paper, and replicating should be
| pretty easy (an undergrad could do it). Because the
| implications are so massive if true, people are going to jump
| on it.
|
| From the linked article:
|
| > You can bet that furnaces in solid-state materials labs
| around the world have been cooking yesterday and today to try
| to reproduce its synthesis and the properties, and we should be
| hearing about the results of these experiments very soon. The
| first samples should be coming out of the quartz vessels. .
| .sometime tomorrow, perhaps? Depends on what was available
| around the lab!
| floxy wrote:
| Yes, that quote from the article makes it seem like everyone
| is dropping everything and jumping right on it. I'm wondering
| how likely that is we'll find out this Friday vs. in the next
| couple of months, as people get around to it.
| kadoban wrote:
| It's an easy thing to attempt to replicate, and it's
| probably _the_ single biggest goal in a particular field of
| science in at least decades.
|
| It's impossible that at least some people didn't drop
| everything to try it.
| bluGill wrote:
| That depends on how easy it is to replicate, and if it is
| true. If it is easy (the 24 hour in the furnace is really
| long enough for everything to get to temperature - 10
| minutes is enough in ideal cases) then we will get lots of
| success Tomorrow. If it is hard, well we will get a lot of
| failures, but a few will try again an in a month as they
| refine technique will report a success.
|
| If it is false we may never get a final report, just
| everyone gives up on reproducing it. (though with the hype
| we may see it like cold fusion were a few not very good
| researchers keep it alive via badly done experiments).
|
| Only time will tell.
| scarmig wrote:
| Friday is more plausible than a couple months. If the radio
| silence ends up extending well-into next week, people are
| having trouble replicating and want to cross their ts
| before calling it out as fraud.
| pfdietz wrote:
| I think if it isn't replicated by tomorrow, it's dead.
| bawolff wrote:
| If i make an analogy to p=np.
|
| If someone claimed to have a complex proof, i dont think people
| would stop and drop everything.
|
| If someone claimed to have a constructive solution to p=np,
| claimed to have implemented it, and put the code on github -
| yeah i think lots of people would drop everything to run it and
| see if it works.
|
| Im not a physicist, but maybe with the relative ease on making
| this material (according to other comments) it is more like the
| second situation.
| hatsunearu wrote:
| For real; the original paper is kinda shitty in terms of data
| presentation, and there's _significant_ value to make a
| follow up paper to create data and try to get your name out
| there.
| distortionfield wrote:
| The author of the paper apparently says it wasn't supposed
| to be leaked and that it needs more work, but he stands by
| his results and will assist anyone trying to replicate,
| which sounds pretty steadfast to me.
| techdragon wrote:
| They have patents... this is the sensible approach to
| take with your intellectual property well defended.
| Between the patents and the published paper establishing
| his role and thus Nobel eligibility...
|
| At this point assisting anybody who wants to help prove
| him correct (and I know that I'm making the assumption
| that he genuinely believes he has made what he claims in
| the paper with the mechanisms and methodology as
| outlined) will just help secure get rich faster and make
| his Nobel prize even more secure.
|
| Polycrystaline materials are kinda finicky so more
| samples helps eliminate the error bars. So obviously why
| didn't they do heaps of samples and have a longer paper?
| ... Money! They got funding for quantum physics based
| sensor/detector research and this appears to have been a
| happy accident, so naturally they kept their heads down,
| got their patents (they have multiple patents each of
| which costs money) and did a little bit more work to be
| absolutely sure, then as soon as it was smart, they
| published their results and are now going to let the
| entire world excitedly double check their results...
| because the results if true, are fucking awesome...
|
| Of course the world wants to replicate this, no one wants
| to be waiting for someone else to confirm a breakthrough
| this big... I bet there's even some corporate labs doing
| a little work on replication too, so some smart managers
| in various industries can factor room temperature
| superconducting materials into their designs and future
| plans sooner, because otherwise their competitors might
| be! (Obviously there's not going to be a lot of this
| since most companies don't have internal science groups
| but the Lockheed-Martins of the world, the Daewoos, the
| Mitsubishi Heavy Industries, the Ratheons ... I'd be
| surprised if they didn't already have someone somewhere
| in the world who is still currently making batches and
| putting them into furnaces because the material is cheap
| and you can get a lot more certainty from additional
| samples if your are prepared to pay for the work. I'd be
| dammed sure someone at General Dynamics is making some
| because it would massively help them convince the US Navy
| to give them more funding to continue work on railguns!
| marcosdumay wrote:
| It doesn't require the kind of equipment that you have to
| justify to accountants and run at full capacity. And while the
| reactants are things that I believe most labs won't have at
| hand, they are the kind of thing anybody can buy on the web to
| arrive this week.
|
| Whether people will stop what they are doing to verify it is
| literally a matter of people stopping what they are doing.
| University labs are usually quick on that.
| mataslauzadis wrote:
| One of the elements used here is phosphorus (P) which is
| regulated by the DEA in the United States, and can't just be
| purchased online
| ckemere wrote:
| Probably ATF, not DEA. DEA regulates controlled substances.
| ATF regulates explosives.
| hackeraccount wrote:
| Wonder element phosphorus can be used for both!
| techdragon wrote:
| Seriously... elemental phosphorus is controlled by the DEA?
| The ATF I could maybe understand but the DEA... that's just
| whacky.
| toast0 wrote:
| If you are at a materials science or physics lab, it can't
| be difficult to get.
| TillE wrote:
| Hell, Sigma Aldrich will sell you LSD. Established labs
| have no trouble with lightly restricted drug precursors,
| they've done all the paperwork.
| JumpCrisscross wrote:
| > _One of the elements used here is phosphorus (P) which is
| regulated by the DEA_
|
| I would have figured ATF. What drug can you synthesize with
| phosphorus? (EDIT: Apparently meth [1].)
|
| [1] https://www.federalregister.gov/documents/2000/09/25/00
| -2455...
| [deleted]
| light_hue_1 wrote:
| > My naive thought is that that labs in general aren't just
| going to drop everything to try an replicate every instance of
| someone declaring they've discovered room temperature
| superconductivity. Seems more like a "there's a lull in paying
| work, so hey, why don't some of you junior technicians try this
| out" thing? Anyone have insight into this?
|
| Labs all over the world are dropping everything to replicate
| this. It's simple self interest.
|
| It only takes 2-3 days and the people involved in the paper are
| credible.
|
| If it's real, your lab would be at the forefront of the biggest
| revolution since the transistor. If it's real, there will be
| hundreds of papers on the topic by next year. Your lab could be
| the one to discover a variant that can carry more current, that
| could have patent on the material of the future power grid. The
| papers that provide the basics for how this works and the data
| that everyone will be using will get 100k+ citations in a few
| years. The PhD students that become experts in this will be in
| high demand everywhere.
| KingLancelot wrote:
| [dead]
| fortysixdegrees wrote:
| This is going to mess up RoHS
|
| https://en.wikipedia.org/wiki/Restriction_of_Hazardous_Subst...
| bawolff wrote:
| There is already a bunch of exceptions for lead, if this is
| useful with no alternatives they would probably just add more
| exceptions.
| cperciva wrote:
| Not necessarily. The "strained crystal" approach probably
| extends to other elements; mixing Pb and Cu works well since
| there's a large difference in their sizes, but rare earths
| might work just as well as Pb.
| NoMoreNicksLeft wrote:
| Can we get those in volumes necessary to do high voltage
| lines though?
| amluto wrote:
| REBCO tape is just starting to be available in volume, and
| I don't think availability is raw materials is even close
| to being a limiting factor.
| varjag wrote:
| RoHS has a number of exceptions. Ambient temp/pressure
| superconductivity will absolutely be excepted too.
| seventytwo wrote:
| Nope, sorry. The EU is probably just gonna pass on RT
| superconductors. /s
| xeonmc wrote:
| See? Brexit was a good idea after all ;)
| konschubert wrote:
| I mean, they are trying to take a pass on AI... I wouldn't
| put it past us.
| [deleted]
| ajuc wrote:
| Lead-acid batteries are mostly lead and legal. I'm sure they
| will make this legal too.
| Exuma wrote:
| So where do we stay up to date with whether it's valid or not.
| mrandish wrote:
| TFA notes that it should be quick to replicate and it's
| definitely gotten enough attention. If the right lab has the
| needed materials readily available, I expect we'll start seeing
| credible people posting excited tweets implying initial
| confirmation as soon as Friday afternoon/evening (assuming it
| replicates on the first go). If we don't see anything by the
| end of next week I'd guess that either it's not replicating or,
| at minimum, it's more finicky than it first appears.
| TigeriusKirk wrote:
| This site will no doubt have the reports in either direction on
| the front page.
| p1mrx wrote:
| https://polymarket.com/event/is-the-room-temp-superconductor...
| graphs the sentiment over time.
| Ajedi32 wrote:
| Slightly more pessimistic than I was expecting given the
| amount of hype this has generated. Though I guess for
| something this groundbreaking a 25% chance that it's real is
| pretty newsworthy.
| amai wrote:
| "I am not enough of a solid-state physicist to judge this
| proposal,..."
|
| I stopped reading after this confession of the author. So this
| text is just as good as a opinion of some other random guy.
| danpalmer wrote:
| I'm not a JavaScript developer, but I can tell if a JS dev is
| bullshitting or if they know their stuff.
|
| The author has enough relevant experience to be able to safely
| conclude a similar thing. They are honest that they won't spot
| minor issues, but my takeaway from this article is that the
| original paper authors are not cowboys or bullshitters, and
| they have a chance at a real finding, subject to regular
| research bugs.
|
| That's good enough to be worth an article!
| gus_massa wrote:
| The articles about chemistry of this author are very good. I
| studied a specialty in Chemistry in secondary school (12-18),
| so I can evaluate most of them but the details are usually
| above my level. When posted here his post get good comments and
| I upvote most (all) of his stories.
|
| His conclusions here are similar to the hivemind opinion in the
| first post https://news.ycombinator.com/item?id=36864624 My
| takeaway is:
|
| 1) It must be confirmed. (And if confirmed it's huge.)
|
| 2) The method to make the material are very easy (if you have a
| good lab)
|
| For me, this post confirm that the chemistry part makes sense.
| Perhaps there was something weird abut the composition of the
| ceramic. Perhaps about the method to make it? If he says that
| it looks fine, for me it's a nice confirmation that it makes
| sense.
|
| The explanation of the effect using "quantum wells" is more
| strange. I feel it's suspicious and that it will be explained
| in a different way in the future. Anyway, I'm neither an expert
| in superconductivity, so I may be wrong. I don't know his
| opinion about the "quantum wells" but I guess he also is not an
| expert in that field to evaluate it.
|
| Superconductivity is a field where the experimental results
| usually arrive long before the theoretical ones, so _assuming
| this is new material is true_ , it is possible that we get a
| lot of new materials in the next 10 years and a good
| theoretical explanation in 50 years.
| algo_trader wrote:
| > (as well as an obvious instant Nobel prize).
|
| South Korea has been waiting for a (real, STEM) Nobel prize for
| decades.
|
| These guys will be worshipped as gods if they deliver
| mrandish wrote:
| South Korea: "We've developed reliable superconducting
| electricity."
|
| North Korea: "We're still working on reliable electricity."
| worik wrote:
| > (real, STEM) Nobel prize
|
| Ouch.
| [deleted]
| nemo44x wrote:
| > These guys will be worshipped as gods if they deliver
|
| And rightfully so. Humanity is moved by great people and these
| would be great people. We would build monuments to them to
| symbolize their importance.
| optimalsolver wrote:
| >(real, STEM) Nobel prize
|
| Alfred Nobel would probably find this characterization very
| ironic.
| carabiner wrote:
| I'd bet the country would be transformed by this. SK
| universities (SNU, KAIST) would rocket in reputation for solid
| state physics research. Massive money inflows to the country
| from production of the material. Deep down I think most of us
| realize that this will probably turn out to be nothing.
| dougmwne wrote:
| It's nothing unless it turns out to be something.
|
| I'll draw an analogy to the LLMs and diffusion models that
| have lately rocked the computer world. These things are
| straight up science fiction. I would have said computers
| would have never been capable of art and poetry. It was all
| fantasy until it was suddenly reality.
|
| We'll probably know if this can be replicated relatively
| soon. And if it can it will kick off a whole new branch of
| materials science and begin a multi-year race to
| commercialization.
|
| We are facing gigantic challenges in energy and climate. We
| need the win, so my fingers are crossed.
| dinvlad wrote:
| LLMs were/are massively overhyped though. Like it's not
| even close to the sort of transformation they promised.
| Neat tech yes, world-changing solution to all of our
| problems? Very hardly, unless a very significant effort is
| spent (and yet undiscovered tech invented) to eliminate all
| of its significant practical problems.
|
| Academics (and similarly venture startup founders) like to
| sort of jump to conclusions along the lines of "discovery
| was the hardest part - now this thing could enable ... in
| the next X years" at the end of a paper. And then people
| spend many decades to actually reduce this to practice. So
| 90% of work belongs to applications, not technology in on
| itself.
| anonylizard wrote:
| Its already overturned the entire art world.
|
| 1.2 years ago if you claimed that an AI will just come
| out and make artists mass panic you would be laughed at.
| Now art is somehow just 'solved'. Progress is continuous
| and massive from Midjourney v1 -> v5
| dinvlad wrote:
| Well, that's exactly what I'm talking about - new
| unproven tech that created more problems that it solved.
| It didn't "solve" art since that is meaningless without a
| human artist. Instead, it stole popular concepts and is
| regurgitating it without any originality or thought put
| into it, and then used "instead" of real artistical works
| by those who don't really understand art, but just need
| "content".
|
| In other words, merely copying/reproducing something is
| emphatically not art.
|
| The same thing happened with traditional (painting) art
| and photography - the latter didn't really replace it but
| just supplanted it in the areas where one wasn't really
| looking for art but for mere reproduction of reality. And
| then over time, photography itself has evolved into art,
| since people have learned how to channel their inner self
| through it, and aimed at quality instead of "quantity"
| (and unlike the former, the latter by itself became
| trivial). I don't see the same happening with generative
| models quite yet (heck, they didn't really replace
| photography either!)
| chasd00 wrote:
| Dude I'm right there with you, fingers crossed!
| CBarkleyU wrote:
| >"real nobel price" "maths"
|
| psht, as if
| nemo44x wrote:
| Apparently the 2 main guys, Kim and Lee have been working on this
| since 1999 and hence the name "LK-99". They worked on other
| things in industry over the years with this on the back burner
| and a few years ago received some funding to pursue this. Kwon
| was brought in to babysit essentially.
|
| At this point they were able to isolate the material but it took
| a few years to figure out how to produce it reliable. They bring
| in HyunTak who has Western ties and has a respectable reputation
| being a well known physical chemist.
|
| They file patents in 2022 and 2023 and some in the group are
| nervous that because the process is so simple they'll get
| scooped. Spies, etc.
|
| HyunTak wants to do more work before publishing but Kwon just
| goes ahead and published the paper with him, Lee, and Kim as the
| authors. HyunTak gets word of this and publishes his paper with
| him, Lee, and Kim and some others later that day.
|
| I think because of this, it is real. Infighting over credits and
| the fact that HyunTak is extremely respectable.
| 9991 wrote:
| Right
| tux3 wrote:
| New scientist got a reply from the authors and a few other
| experts: https://www.newscientist.com/article/2384782-room-
| temperatur...
|
| >Kim has only co-authored one of the arXiv papers, while the
| other is authored by his colleagues at the Quantum Energy
| Research Centre in South Korea, some of whom also applied for a
| patent on LK-99 in August 2022.
|
| >Both papers present similar measurements, however Kim says that
| the second paper contains "many defects" and was uploaded to
| arXiv without his permission. In that paper, the work is
| described as opening a "new era for humankind".
|
| >Other experts that New Scientist consulted were similarly
| sceptical about the results and the data produced. Some raised
| concern that some of the results could be explained by errors in
| experimental procedure combined with imperfections in the LK-99
| sample.
| antimatter15 wrote:
| Seems interesting that there appears to have been a patent
| application for LK-99 (https://patents.google.com/patent/KR2023
| 0030188A/en?oq=WO202...) filed two years ago in August 2021 (a
| year earlier than the article suggests).
|
| If true, it seems wild to sit on this kind of discovery for
| over two years.
|
| Update: Seems like there might be even more history given the
| name LK-99 apparently comes from the names of its discoverers
| Dr. Lee and Dr. Kim, and the year of its discovery, 1999
| (https://kr.linkedin.com/in/ji-hoon-kim-03508b80).
| yreg wrote:
| Naive question: is that the original content of the
| application from 2021, or could it have been updated later?
| Is it the same material as LK-99 in the published paper?
| nazgulnarsil wrote:
| quick googling appears to indicate that it was produced in
| trace amounts as a consequence of other experiments at that
| time and only was investigated in and of itself in larger
| amounts more recently? Awaiting more info from better
| informed people.
| tigershark wrote:
| "Both papers present similar measurements"
|
| I'm not a physicist expert of superconductors, although I've
| followed quite closely that field since the '90s. But if the
| measurements are similar and correct and if the video of lk-99
| levitating above a magnet demonstrating the Meissner effect is
| not fake, I don't really have an alternative explanation to
| account for all of that. I guess that we'll see what happens in
| the next week or two. This is too high stakes to take longer
| than that for a so easily reproducible experiment.
| abrichr wrote:
| > the video of lk-99 levitating above a magnet demonstrating
| the Meissner effect
|
| Can you please provide a link?
|
| Edit: found it https://sciencecast.org/casts/suc384jly50n
| drexlspivey wrote:
| This guy is live tweeting his attempt to reproduce
| https://twitter.com/andrewmccalip/status/1684433849781202944
| justinclift wrote:
| Seems to be a single post?
| Thrymr wrote:
| Because X (sigh) doesn't show replies in public (if not
| logged in) anymore.
| justinclift wrote:
| Ahhh. Thanks. :)
|
| Yeah, I can't be bothered logging in.
| codethief wrote:
| There you go: https://nitter.net/andrewmccalip/status/168
| 4433849781202944
| justinclift wrote:
| Fantastic, thank you. :)
| hackerting wrote:
| You have to login to view the thread. The new Twitter
| made it super confusing, I guess the UX designers are all
| gone at this point at X
| nazgulnarsil wrote:
| It has been proposed that alternative mechanisms besides SC
| can create diamagnetic effects. I think we're waiting on more
| informed updates because the people with the competence to
| comment on this are probably _working furiously in a lab
| right now_ rather than commenting.
|
| edit: useful comment elsethread by macromaniac on
| plausibility of diamagnetic effects
| hinkley wrote:
| Is that, "I never meant to publish this," or is that, "It was a
| rough draft that I hadn't edited for accuracy or tone and fuck
| Steve for uploading it."
| bglazer wrote:
| I'm guessing the second. Nothing in the interview suggests
| that he doesn't stand behind the data. Sounds like he's
| taking a wait and see approach and it's a very good sign that
| he's offering to help other researchers try to replicate
| elfbargpt wrote:
| I really think this could be in-fighting for the third Nobel
| prize spot (if it turns out to be legitimate). I pointed this
| out in another comment, but the first two authors are the the
| LK-99 material namesake and will likely always be the first
| two authors.
|
| "YW Kwon" published the first paper with himself as the 3rd
| author, and "HT Kim" published the second paper a few hours
| later with himself as the 3rd author.
|
| Pretty interesting drama if that's the case. May indicate
| neither paper was ready, but that they all think the result
| is legitimate.
| DarmokJalad1701 wrote:
| Without paywall: https://archive.is/Lve8I
| scarmig wrote:
| One odd thing that I've not seen any discussion on: the reported
| heat capacity of LK-99 decreases above 250K, which is pretty
| atypical. Has there been any commentary on that?
| groestl wrote:
| > Has there been any commentary on that?
|
| German, but nevertheless: http://blog.fefe.de/?ts=9a3f8740
|
| "I work in the field [...] we don't believe a word of this.
| [...] The data set in Fig. 4(b) is also a treat. It is VERY
| unusual when the heat capacity decreases again at high
| temperatures. This can happen at low temperatures, but not at
| high temperatures. [...] My personal assumption is that the
| authors measured an insulator, so no current flow and therefore
| no voltage occurred (4-point measurement). This would look like
| a superconductor. But if you then turn up the current (i.e. the
| applied voltage), breakdowns may occur and a current begins to
| flow. That would explain the sharp increase."
| scarmig wrote:
| Nice find.
| distortionfield wrote:
| Not really, it's just more speculation about the
| experiment. It's worth as much as anyone else's salt about
| the matter.
| fh973 wrote:
| It's from a guy of the Max Planck Institute for Solid
| State Research.
| nemo44x wrote:
| He sounds rather bitter and arrogant. He basically just
| called them idiots. As if none of the researchers would
| have noticed the measurement error. Perhaps he's right -
| we'll know in a few days I assume. I do hope they are
| right though not only because it would be a huge leap but
| also because I'd love to see this guys reaction.
| xdennis wrote:
| > He sounds rather bitter and arrogant.
|
| That might be your interpretation of it. I think the
| Germans would call it being straightforward.
| groestl wrote:
| It's a cultural thing, we tend to spare the buns from the
| sandwich feedback ;)
| stu255 wrote:
| Lee and Kim have been working on this stuff for a long
| time. They published prematurely after major falling out
| within their institute.
|
| This isn't 1 experiment as the Germans seem to think.
| There are multiple papers, patents, etc.
|
| The main focus of these papers has been to make huge
| claims and make replication very easy. They are "all in"
| and they want others to call.
|
| If they were bluffing they would be heavy on results and
| light/secretive on how to make the stuff (trade secret,
| etc).
|
| That's why there are 2x papers published within 3 hours,
| both with different authors, and you have one author
| telling New Scientist he did not approve of a paper
| naming him as an author.
| top_sigrid wrote:
| Came here to mention this. Here is a full deepl translation
| of the post, for those who are interested (in the above
| linked post of a blog the blog author recites a mail from one
| of his readers):
|
| "I work in the field and we discussed the preprint a bit in
| the research group this morning. In a nutshell, we don't
| believe a word of it: Fig. 1(a) and (c) are
| implausible. Normally, this sort of thing looks like this.
| Note the gradual increase at low currents, this effect is
| especially expected for magnetic fields. Also
| Fig. 1(d) cannot be correct. At Tc ~ 400K the Meissner effect
| would displace a much stronger field than 10 Oe = 1 mT. I.e.
| the distinction between FC (field cooled) and ZFC (zero-field
| cooled) should not be so pronounced. It should look more like
| this.
|
| What the authors might mean is that they are outside the
| Meissner range, which can occur at higher magnetic fields
| (keyword: Type II superconductors). This then looks like
| this.
|
| But in this case the temperature dependence does not agree at
| all with the critical currents of Fig. 1(a) and (c).
|
| And also that ALL values in Fig. 1(d) are negative is
| extremely unusual, but this could perhaps be argued.
| The data set in Fig. 4(b) is also a treat. It is VERY unusual
| to see the heat capacity decrease again at high temperatures.
| This can happen at low temperatures, but rather not at high
| temperatures. I know the described experimental
| setup / cryostat very well. There is no reasonable reason why
| the authors did not measure at higher temperatures to show
| that the behavior above Tc ~ 400K is significantly different.
| E.g. a temperature dependence of the resistance would have
| been mandatory. In general, the paper is very
| poorly written. The data are not adequately discussed, the
| explanations are poor, and the papers cited are rather, shall
| we say, meager. This does not inspire confidence in what the
| authors have measured and want to have seen there.
| My personal guess is that the authors measured an insulator,
| accordingly no current flowed, and thus no voltage occurred
| (4-point measurement). Then it looks like a superconductor.
| But if you then turn up the current (i.e. the applied
| voltage), there may be breakdowns and a current starts to
| flow. This would explain the sudden increase."
| RyanAdamas wrote:
| Wow, that's pretty damning. Good one.
| jeepers6 wrote:
| "Damning" is the wrong word here. "Damning" would be "oh,
| look, the researchers forgot that the plot showing zero
| voltage also shows current dropping to zero. They're
| clearly measuring a bad contact."
|
| But the papers don't show that. There's no obvious
| contradiction unless you make some big assumptions.
| singularity2001 wrote:
| OP works in the field and provides good arguments. You
| can translate the full blog post.
| amluto wrote:
| A 4-point measurement of an insulator would show zero
| current, as far as I know.
|
| A more plausible idea IMO is that it could be a 4-point
| measurement of a highly inhomogeneous sample. If the current
| probes make contact with conductive parts of the sample, and
| there is a conductive path between them, but one or both
| voltage probes are not contacting the conductive path, then
| the voltage measurement would be garbage and potentially
| zero.
|
| I don't think this is much of a problem when measuring
| conventional conductors (you don't need a particularly _good_
| contact, which is much of the point), but a lot of
| superconductors are oddball materials where, under conditions
| where they fail to superconduct, they barely conduct at all.
|
| So maybe the sample has a conducting phase and an insulating
| phase?
| BizarroLand wrote:
| Wouldn't it be odd for an amalgam of lead and copper to be
| non-conductive?
|
| I know they were formed from sulfur compounds, but the
| production process should have eliminated those compounds,
| and the final forming is done in a vacuum so there
| shouldn't be any oxide generation to form non-conductive
| barriers.
|
| I don't know much about the process but shouldn't they be
| testing resistance in a superconductor?
| scentoni wrote:
| It's not an amalgam (that means a mercury alloy) or any
| metallic alloy. It's an oxide (more complicated than that
| but there's more oxygen atoms than metal atoms).
| BizarroLand wrote:
| Amalgam can also mean, "A mixture or combination of
| different things" such as "an amalgam of musical genres"
| or "an amalgam of unsavory dog food flavors", which,
| since we aren't talking about mercury at all, nor are we
| talking about any form of dentistry, should have be
| evident and deducible from the context.
|
| https://www.oxfordlearnersdictionaries.com/definition/eng
| lis...
|
| And we very much are talking about an alloy, which is a
| "metallic substance composed of two or more elements"
|
| https://www.britannica.com/technology/alloy
|
| Lead is a metal. Copper is a metal, a combination of 2
| metals is an alloy.
|
| However, you are right, I did overlook that the compound
| is an oxide, my bad.
| singularity2001 wrote:
| A 4-point measurement of an insulator would show zero
| current, as far as I know.
|
| The blog post suggests it might be electrical breakdown of
| the material at a certain voltage
| [deleted]
| floxy wrote:
| Since it is apparently expected that the material is almost
| trivial to synthesize, I'm wondering why the original group
| hasn't tried to get an outside independent source to verify one
| of their samples before dropping this on the arXiv? Is there some
| other internal reason/pressure to release this now? Like they've
| tried to be in stealth mode for the two years since applying for
| the patent, but risks of leaks are growing, and now they are
| rushed? Or maybe they have had some independent outside
| confirmation, but I guess you don't need to share it if you know
| you've got the goods, and are confident that everyone will be
| able to reproduce it in short order. Otherwise, I'd think I'd be
| trying to have 100 samples queued up for anyone who wants to
| verify.
| sanxiyn wrote:
| As far as I can tell, https://arxiv.org/abs/2307.12008 is the
| paper by the original group and
| https://arxiv.org/abs/2307.12037 is the paper they wrote with
| an outsider. Their chosen independent outsider is Hyun-Tak Kim.
| wenyuanyu wrote:
| Exactly opposite, they needed to drop this on arXiv first to
| stake their claim before anyone else. It's open for everyone to
| test out now, so if it's legit, we'll know soon. Also, it's a
| smart move if they're worried about leaks, now they're in
| control of the news.
| elfbargpt wrote:
| One interesting thing I saw pointed out on twitter: both of the
| published papers have "Lee" and "JH Kim" as the first two authors
| (LK-99 material namesake).
|
| The first paper was published by YW Kwon with himself as the
| third author. The second paper was published a few hours later by
| Hyun-Tak Kim with _himself_ as the third author. As others have
| pointed out there can only be 3 names on the ticket for a nobel
| prize.
|
| To me this might indicate that they all think the result is
| potentially nobel-worthy, and also that the papers may not be as
| complete / rigorous as they should have been due to this drama /
| race to publish (YW Kwon published without permission to get his
| name out there, forcing Hyun-Tak to push his out a few hours
| later)
| Koiwai wrote:
| If this is true, I think the nobel prize committee would
| happily make an exception for them.
| dustypotato wrote:
| The K-Drama I'd like to follow :)
| mitthrowaway2 wrote:
| If this is real, it's worth a nobel in both physics _and_
| chemistry, so there are plenty of accolades to go around!
| obblekk wrote:
| The researchers definitely believe it's real - they're fighting
| over who gets credit (hence the double paper publication).
|
| Only a few days left until replications should start pouring
| in...
| jonplackett wrote:
| If this material does just what they say it does, what would it
| revolutionise?
|
| Or as the article talks about, is this just a pointer at other
| possibilities that would be the real game changers?
| soligern wrote:
| I'm just thinking aloud here but would this enable actual
| perpetual motion machines? For instance, wouldn't the pushback
| from the quantum locked superconductor be an infinite source of
| energy?
| m4x wrote:
| In the same way that the pushback from the earth you're
| standing on is an infinite source of energy
| soligern wrote:
| It isn't though. You can use gravity to apply the weight to
| the superconductor and the pushback would be against
| gravity.
| p1mrx wrote:
| You can also hang a weight on a spring. Neither helps you
| override the laws of thermodynamics.
| p1mrx wrote:
| > wouldn't [x] be an infinite source of energy?
|
| In general, the answer to this question is "no."
| tamimio wrote:
| I would build a drone that levitates indefinitely.. for a
| starter.
| m463 wrote:
| but not above 400 feet.
| tamimio wrote:
| And doesn't exceed 25kg.. at least per the silly TC
| regulations here in Canada.
| terafo wrote:
| Can you explain this part?
| [deleted]
| m463 wrote:
| like parking tickets for supercars... :)
|
| FAA says even superconducting superdrones can't go over
| 400 feet.
| terafo wrote:
| And can you also explain "indefinite levitation" to me?
| IIRC you can do some levitation over metallic surfaces or
| magnets, but that would require power, wouldn't it?
| m463 wrote:
| not qualified to explain the levitation, seems to be some
| sort of self-stabilizing magnetic field due to zero-
| resistance current.
|
| But there is plenty of magnetic levitation right now
| without power:
|
| https://www.amazon.com/dp/B01N2Z9QAP
|
| also, balloons.
| neltnerb wrote:
| I mean, it depends a lot on how ductile a final product is.
| High temperature superconducting "wire" took a long time to
| become realistic. If you somehow made a ductile and inexpensive
| wire out of it then it's going to be everywhere (and lead
| poison everyone for generations, but that's progress for you).
|
| Of course if you can make wire out of it, I wonder how much
| smaller your fusion reactor can get?
|
| There are a lot of applications for even a thin film, consider
| spray coating a resonant cavity with it.
|
| I'm sure there is a way to improve almost anything you could
| think about if you start talking about making CPUs with lower
| heat dissipation, perhaps enabling 3D designs and much more
| efficient computing... [edit: obviously there is a limit from
| literally the entropy in computing and transistors are most of
| that, I wonder if the superconductor is a good thermal
| conductor...]
|
| I'm sure there are at least 222 startups that have some idea
| they're pitching right now ;-)
| elihu wrote:
| I think it'd be valuable for anything that conducts
| electricity, and where resistive losses are significant or
| where strong electromagnets are desired.
|
| So, long distance electricity transmission, motors, generators,
| MRI machines and magnetic confinement nuclear fusion reactors
| for example.
|
| That said, the material as synthesized might not be very good
| for some particular application. The current handling capacity
| might not be good enough, or it might not be physically strong
| enough to use as motor windings.
|
| I don't know enough to do the comparison, but I'd be curious
| how this new material holds up when compared to copper or
| aluminum wire in terms of current capacity, weight, strength,
| and cost of materials. One of the big reasons for skepticism
| about humanity's prospects for converting to a non-fossil-fuel
| based energy system is that there just isn't enough of the
| important metal resources to build all the
| batteries/EVs/transmission lines/solar panels/windmills we
| need. I myself am skeptical of the skeptics because I think the
| resource bottlenecks are overstated and there are usually
| acceptable workarounds, but I do think copper is going to be in
| very high demand over then next several decades. If we have a
| good, cheap copper alternative then that solves that problem.
| (It also introduces another, as we would then have to deal with
| enormous quantities of lead-based cabling.)
| carabiner wrote:
| Video games will be more realistic.
| mitthrowaway2 wrote:
| ... In the sense that reality will become more like it is in
| video games?
| RC_ITR wrote:
| A lot of people are talking about very cool practical use
| cases, but I'm here just thinking 'all of our trains could
| float, wouldn't that be neat?' [0]
|
| [0]https://en.wikipedia.org/wiki/SCMaglev
| scarmig wrote:
| I'm excited about the ball bearings.
| XorNot wrote:
| New era of sound proofing too: RT superconductors and
| neodyminium magnets levitating your inner-room separate
| from the building.
| bick_nyers wrote:
| Finally I'll be able to get some good sleep!
| Vecr wrote:
| How much would that reduce sound if they were quantum
| locked?
| Fordec wrote:
| In the immediate short term, the power level supported is too
| low for the real shiny applications that everyone talks about.
|
| But the main one that is screaming at me for this technology
| sitting in front of us is SQUID sensors and RF antennas that
| will operate in the lower power range of the potential
| applications spectrum.
| hatsunearu wrote:
| how does superconductivity benefit RF antennas?
|
| AFAIK loss at AC still occurs with superconductors because
| the dielectric loss through the materials still exists.
| floxy wrote:
| https://en.wikipedia.org/wiki/Superconducting_radio_frequen
| c...
| superkuh wrote:
| Search "superdirective superconducting antenna". With
| normal conductors the directivity of an antenna depends on
| how many wavelengths it spans; the summation of the
| currents over the effective aperture. With superconducting
| materials you can exploit the weirdness in current
| distribution to make very directional antennas that are
| _small_ relative to the wavelength.
|
| It could be a game changer for making efficient directional
| small receive antennas. Normally electrically small
| antennas are just super inefficient but it's made up for
| either on the transmit side (like with high power AM radio)
| or with most of the gain coming from some low noise
| amplifier (like small UHF wireless devices).
| carabiner wrote:
| Could we get high speed satellite internet on a
| cellphone?
| superkuh wrote:
| Probably not. It will make the really small really
| inefficient antennas stuck in things like 2-5x better.
| But they still won't be outperforming full size resonant
| non-superconducting antenna.
| TedDoesntTalk wrote:
| > what would it revolutionise?
|
| "Human sacrifice! Dogs and cats living together! Mass
| hysteria!" --Venkman
| local_issues wrote:
| Fusion.
| [deleted]
| lofatdairy wrote:
| MRIs would be another revolutionized field. Cooling is a big
| size constraint and cost driver. You would still need a large
| amount of power if you want to have clinical scans at 3T or 5T,
| though, but in wealthy countries the number of MRI machines
| would for sure proliferate and it would probably become more
| routine. Low-resource environment deployments may become a tad
| more feasible, to be honest the power requirements will still
| probably be too high, but at least you wouldn't need an always-
| on source.
| gene-h wrote:
| As far as I can tell the critical field, the maximum magnetic
| field it can withstand before turning into a regular conductor,
| is relatively low at 0.3 Tesla. In superconductors like YBCO,
| it's often more than 100 T. If critical field cannot be
| increased this will limit applications.
|
| Near term may be useful for devices which take advantage of
| quantum effects such as Superconducting QUantum interference
| devices or SQUIDs.
|
| Use in microelectronics may be possible, but is likely quite
| difficult. Making complicated structures out of this material
| will require radically new microelectronic manufacturing
| processes. HTSC microelectronics don't exist as far as I can
| tell.
|
| If critical field can be improved things get interesting. If it
| can be increased to that of known HTSCs at liquid nitrogen
| temperatures(critical field scales with temperature), that's
| interesting because this material should be cheaper.
|
| If it can be increased moderately at room temperature, there is
| the potential for it replacing rare earth magnets because the
| material should be cheaper.
| foven wrote:
| 0.3 T is pretty insignificant for everyday use - you need
| some pretty big coils carrying around 10 A to produce that
| sort of field. For something like this, the benefit would be
| in just making wires out of it for driving currents without
| loss of power (no resistance, no heating). Think big bulky
| overhead wires - but it's all moot if the material isn't a
| superconductor.
| spaceman_2020 wrote:
| Well for starters, you would never have to hear that awful fan
| noise from your computer :)
| syntaxing wrote:
| There's a ton of electromagnets that are super cooled (like
| single digit K cold) so that it can maintain a large magnetic
| field. While this is only the first step, pretty much any
| application that does something similar can be replaced with
| this room temperature super conductive material.
|
| Not only products would be impacted but experiments too,
| particularly particle experiments. All colliders need some sort
| of ridiculous magnetic field which uses a close loop helium
| chiller.
|
| Long term wise, anything that uses electromagnetic fields would
| be impacted, like motors and generators. You in theory can get
| stupidly efficient motors (99%+) motors with super conductors.
| flangola7 wrote:
| Explosive weapons chargeable to any yield. Take a loop of
| superconductor charged to the desired current, then warm it
| beyond its critical point, dumping the electrical energy into
| immediate heat. A 120mm tank shell is in the 10s of Kilowatt-
| hours. No more special chemicals, just this lead based super
| conductor and 20 minutes on an EV fast charger. Don't forget to
| take it off the charger!
| ska wrote:
| Lots of systems with bulky and expensive cooling (think MRI
| scanners, e.g.) could become vastly more accessible.
|
| Wildly improved efficiency on some sensors, antenna, motors,
| etc.
| hovering_nox wrote:
| Here's a few from the top of my head:
|
| - A global power net. No solar power during the night? Just
| produce it on the other side of the planet.
|
| - A superconducting computer. Less resistance when pushing bits
| around = 500x less power consumption.
|
| - A Superconducting magnetic battery. Store power indefinitely
| with high efficiency.
| scarmig wrote:
| Most power loss in a computer comes from MOSFETs, not
| resistive loss. Which isn't to say that RTP superconductors
| wouldn't open up wild new possibilities.
|
| ETA: wrong
| hovering_nox wrote:
| _Much of the power consumed, and heat dissipated, by
| conventional processors comes from moving information
| between logic elements rather than the actual logic
| operations. Because superconductors have zero electrical
| resistance, little energy is required to move bits within
| the processor._
|
| https://en.wikipedia.org/wiki/Superconducting_computing#Fun
| d...
| ummonk wrote:
| That statement in Wikipedia is flat out wrong and notably
| isn't citing any source.
| amelius wrote:
| Incorrect.
|
| https://www.ti.com/lit/an/scaa035b/scaa035b.pdf
|
| This document explains it well. (The resistance of the
| interconnect is not even mentioned as a significant
| component of power consumption.)
| XorNot wrote:
| You can synthesize superconducting FETs though: https://l
| ink.springer.com/chapter/10.1007/978-94-011-1918-4_...
|
| Obviously this isn't much benefit since the vast majority
| of applications can't be liquid nitrogen cooled (and
| computing has followed "what consumers will buy" on
| progress).
|
| That changes substantially if superconductors will keep
| working when put in my pocket.
| hatsunearu wrote:
| I don't think this is true. Most of the power is dissipated
| in the metal interconnect.
| bick_nyers wrote:
| Not only less power consumption on Computers but a 100x
| improvement in clock speeds, a 500GHz CPU would be absolutely
| insane.
|
| Whether or not we can manufacture/shrink the superconductor
| circuits enough to be competitive with semiconductors is
| another question, but my naive interpretation is that if you
| can make the superconductor circuits 100x larger than a
| silicon circuit, it is still going to have significant
| advantages.
| jimkoen wrote:
| > A global power net. No solar power during the night? Just
| produce it on the other side of the planet.
|
| This sounds like it has interesting ramifications for global
| politics. At the beginning of the Ukraine war, one major
| lever the Russian government had was to enable blackouts in
| Ukraine. Makes you wonder how a global power network could
| work in light of international conflict.
| pyrale wrote:
| If yesterday's comments were correct, you can strike the
| power transport and storage use cases, as this material has a
| pretty low electric current density.
| SkyBelow wrote:
| Wouldn't less power loss not just mean lower power
| consumption, but the ability to run it at higher speeds while
| keeping the same cooling technology we current have?
| bick_nyers wrote:
| Even faster. That is to say, even faster than a
| semiconductor CPU that didn't generate any heat whatsoever
| (or was cooled with liquid helium).
|
| Assuming of course it is possible to shrink the
| superconductor circuits down to the same size of the
| semiconductor counterpart.
| wcerfgba wrote:
| If this is real, what are the
| consequences/impacts/implications/applications? I don't know
| anything about superconductors!
| MayeulC wrote:
| Well, There are countless comments addressing this, but
| possibly more on the earlier thread
| https://news.ycombinator.com/item?id=36864624
| mmastrac wrote:
| This is an extremely useful summarization of the original paper.
|
| > The authors believe that the modified/strained structure of
| their material creates a large number of "quantum wells" between
| particular lead atoms and the adjacent oxygens of the phosphate
| groups bound to them, in effect making a two-dimensional
| "electron gas". They propose that electron tunneling between
| these quantum wells, which are between 3.7 and 6.5 Angstroms
| apart, is the superconducting mechanism. I am not enough of a
| solid-state physicist to judge this proposal, but the authors are
| making a detailed mechanistic claim that is subject to
| experimental proof, which is very good to see, and and they
| adduce a good deal of data to back it up (x-ray diffraction, EPR,
| and more). And they demonstrate the behaviors that a
| superconductor should have, such as the Meissner effect
| (expulsion of a magnetic field), sudden resistivity changes at a
| critical temperature (bizarrely high though that is in this
| case), current-voltage (I-V) plots at different temperatures and
| under different magnetic field strengths, etc. If these data
| reproduce, the superconductivity of this material seems beyond
| doubt.
| cma wrote:
| > sudden resistivity changes at a critical temperature
| (bizarrely high though that is in this case)
|
| How high? Just wondering if it might eventually be possible to
| use it in some power/clocking distribution layers of a
| semiconductor chip without bulky cooling.
| jacquesm wrote:
| 127C!
| elihu wrote:
| That's a good idea. Honestly, I find it pretty amazing that
| modern CPUs don't just instantly turn into a puddle of molten
| metal as soon as you turn them on.
|
| The critical temperature is 127 C, as the other commenter
| mentioned. That seems like it's high enough to be useful in a
| computer CPU.
|
| I suppose there might also be applications for power
| distribution in a data center. You might use a few large,
| high-efficiency low voltage DC power supplies to supply the
| whole site instead of hundreds or thousands of individual
| power supplies if electrical resistance in cables was less of
| an issue. (I think this sort of thing is done now, but more
| at the rack level, since long cable runs cause losses.) You
| might even use 1V power instead of 5V or 12V.
|
| (Granted, superconducting materials don't have unlimited
| current capacity, and bad things happen if you exceed the
| limit.)
| axiomaticdoubts wrote:
| The critical temperature is not 127 C. They did not
| actually measure the critical temperature. They just said
| it's _at least_ 400 K (~127 C), probably because that was
| the maximum temperature the equipment they used could
| measure.
| pjc50 wrote:
| > Just wondering if it might eventually be possible to use it
| in some power/clocking distribution layers of a semiconductor
| chip
|
| There's an additional obstacle factor here which is that the
| material has to (a) be "sputterable" onto the surface, which
| may rule out things with fancy crystal requirements, and (b)
| not adversely react with the rest of the chip, which is why
| coppper is ruled out (!) and chips use aluminium for metal
| layers.
| cma wrote:
| Copper replaced aluminum some time ago (starting ~1997)
| regardless because of the resistivity, and they just had to
| find different barrier materials to prevent
| electromigration and overcome other issues.
| AndrewKemendo wrote:
| Totally agree. This is science at it's best, with maximum
| skepticism (and a dash of hope), in front of our eyes!
|
| Even better, it's a HUGE claim that is going to show how
| epistemology in science works (reproduction!!)
| akjssdk wrote:
| I don't think the actual proposed superconductivity mechanism
| is the relevant part of this paper. It is much easier to prove
| that this is superconducting than to prove why. And in a sense
| it is a bit less relevant. Although developing a working theory
| for room temperature is also probably worth a Nobel prize, so I
| am willing to bet some theorists are also running to their
| blackboards as we speak.
| glenstein wrote:
| >I don't think the actual proposed superconductivity
| mechanism is the relevant part of this paper. It is much
| easier to prove that this is superconducting than to prove
| why.
|
| As another commenter has pointed out, the proposal of a new
| mechanism seems to be extraordinary and novel, and could lead
| to an explosion of new research, so it does indeed seem to be
| "relevant" on its merits.
|
| I also don't see this as a case of the "why" being left
| unexplained. In the history of superconducting it has indeed
| been the case that new cocktails have led to
| superconductivity without the underlying why being
| understood. But the commenter that you're responding to
| quotes part of the paper that shows an awfully specific
| mechanism.
|
| I understand the sense in which there can be a "why" that
| remains to be explained in certain circumstances, even when
| you have a mechanism. Who do monarch butterflies have the
| black and orange pattern on their wings? There's a cause and
| effect answer but there's also a "why" answer. But with
| superconductivity, the mechanism _is_ the why, unless I 'm
| misunderstanding here. If other forms of superconductivity
| rely on other mechanisms, there isn't going to be a general
| why connecting this case to the other cases, but nor is there
| anything left unexplained just by explaining the "why" of
| this case by explaining it's extraordinary mechanism.
| ethn wrote:
| They made a synthetic a priori prediction proven by
| experiment. In science, that's the strongest type of claim.
| seeknotfind wrote:
| You might also say it's the only type of claim science
| recognizes. Though, whatever or how strong a claim is, the
| question is how important is what is proven and will it
| lead to real superconductive materials.
| throwawaymaths wrote:
| The strongest type of claim is when an a priori claim is
| called absurd, someone goes to make observations to
| disprove it and comes back convinced of your theory.
| aaron695 wrote:
| [dead]
| fnordpiglet wrote:
| I'm not entirely sure that's true. A posit in the paper is
| this is a novel super conducting mechanism and as such if the
| mechanism is true it's totally unexplored. That leaves open a
| huge field of new research. That's certainly a relevant part
| of the paper. Super conductivity at room temperature is an
| amazing breakthrough alone, but if it was with a clever tweak
| with an existing well established technique that would be the
| end of the story. The fact it's an entirely new technique
| opens a world unexplored and indicates a pathway to even more
| amazing discoveries to be had (and funding for entire
| generations of physicists).
| glenstein wrote:
| Right. The mechanism itself seems extraordinary. And it
| seems like that mechanism is exactly the "why", the
| commenter is claiming is more important.
|
| Moreover, you can have more than one thing about a paper be
| the "relevant" thing.
| Terr_ wrote:
| > I don't think the actual proposed superconductivity
| mechanism is the relevant part of this paper.
|
| Plus even if the proposed-mechanism is incorrect and even if
| the effect is not strong enough for practical engineering...
| There's value in a "real" (if weak) superconductor which is
| both easy to fabricate and easy to run tests on.
|
| It could become a starting-point for dozens of other tweaked
| formulations, enabling all sorts of not-so-expensive
| experiments and fresh data about how different parameters
| lead to different electromagnetic outcomes.
| local_issues wrote:
| Ding ding ding! We still don't know how bikes work, we have a
| pretty good but incomplete model for lift on airplanes, and
| no one has the faintest why Tylenol works.
|
| We should figure that out! But we can definitely keep using
| all the applications until then. (Except for Tylenol, we keep
| learning how bad that stuff is)
|
| EDIT: It won't let me post more, so here's the answers to
| responses.
|
| For sure!
|
| https://www.cbc.ca/news/science/science-of-cycling-still-
| mys...
|
| http://www3.eng.cam.ac.uk/~hemh1/gyrobike.htm
|
| https://www.newscientist.com/article/mg22730370-400-how-
| does...
|
| It's a fun little fact. We know a ton about BUILDING bikes,
| which is a more useful tool anyway
| intrasight wrote:
| We don't know how photosynthesis works but we know a ton
| about GROWING things. And life as we know it depends on
| photosynthesis.
| MVissers wrote:
| I thought we had a pretty good understanding of this up
| until the molecular and electron level.
|
| Am I missing something?
| dotnet00 wrote:
| How photosynthesis works at a cell machinery level is
| high school level biology.
| ummonk wrote:
| Nonsense. There's nothing incomplete about our model for
| lift on airplanes.
| aeternum wrote:
| Oh really, so why do the Navier-Stokes equations work?
| ummonk wrote:
| If you're asking how to apply the Navier-Stokes
| equations: apply boundary conditions
|
| If you're asking how to derive the Navier-Stokes
| equations, use continuum / conservation principles.
| dkqmduems wrote:
| Conservation of momentum?
| bandrami wrote:
| There's no _a priori_ reason conservation of momentum
| would apply; for that matter in 0-angle-of-attack
| aviation it doesn 't.
|
| Maybe to put it differently, the "Newtonian" model of
| flight comes out of _assuming_ CoM applies, which we know
| isn 't universally true.
|
| EDITING: of course it always "applies" in the sense that
| there is a definable system in which total momentum will
| be unchanged, the point being that there is no guarantee
| that's a system in which the plane gets lift greater than
| its weight
| coderenegade wrote:
| A symmetrical airfoil at zero angle of attack doesn't
| generate lift because it doesn't turn the fluid. A non
| symmetrical airfoil will generate lift even at zero AOA
| because air has viscosity and the lack of symmetry causes
| it to turn around the shape. When you bend fluid flow,
| COM comes into play.
| [deleted]
| [deleted]
| mthomasmw wrote:
| Do you have a link handy for "we don't know how bikes work"
| ?
| hatsunearu wrote:
| Yeah, that's complete crap. Bike dynamics is well
| researched and the instability and stability mechanisms
| are numerous but well understood.
| hughw wrote:
| e.g. _What keeps bicycles balanced with or without a
| rider is still an active area of research, and even the
| seemingly basic idea that, for a bicycle to be self-
| stable, it needs to turn the handlebars into the fall,
| has not yet been proven._
|
| [*]https://ciechanow.ski/bicycle/
| IshKebab wrote:
| "Active area of research" is quite different to "we don't
| know how they work".
|
| We know how they work. We might not have _fully
| characterised the stability conditions_ , but that's not
| the same thing.
| babypuncher wrote:
| I think their point still stands, even if "we don't know
| how bikes work" is a flowery exaggeration.
| IshKebab wrote:
| But then we don't know how anything works...
| DonHopkins wrote:
| Yet we still have Insane Clown Posse refrigerator
| magnets.
|
| https://www.insaneclownpossemerch.com/collections/insane-
| clo...
|
| Scientists Try To Teach ICP Fans How Fucking Magnets Work
|
| https://metalinjection.net/av/scientists-teach-icp-fans-
| fuck...
| babypuncher wrote:
| But their point is we don't need a 100% complete
| scientific understanding of something in order to
| engineer it into something cool or useful.
| IshKebab wrote:
| That is true, but it's still incorrect to say we don't
| understand how bicycles work.
| hughw wrote:
| Cmon, man
| salty_biscuits wrote:
| You can write out the equations of motion for a bicycle
| that will very accurately predict the dynamics. You can
| put these equations into a numerical simulation and
| predict motion very accurately. You can change the
| parameters of the model and do simulations with high
| confidence. Just because there isn't some neat little
| equation that says exactly what each parameter change is
| going to do (without doing the simulation) doesn't mean
| that we don't understand bicycle physics. It's a silly
| line of reasoning. Those articles are hyperbolic.
| ddalex wrote:
| You are contradicting yourself:
|
| > You can write out the equations of motion for a bicycle
|
| > there isn't some neat little equation that says exactly
| what each parameter change is going to do
|
| I mean, if you have the equations you can see what each
| parameter is doing !
| salty_biscuits wrote:
| Algebraic versus differential if that wasn't clear
| jerf wrote:
| Something smaller than may help you grasp this idea:
| https://www.youtube.com/watch?v=5nW3nJhBHL0
|
| There are things we can characterize to any desired
| degree of accuracy but that e don't get cute little
| equations out of... and some of those things are so
| simple they've been staring you in the face since middle
| school and you just didn't ever notice their absence from
| your formula sheets.
|
| This is not the exact same situation being described but
| it's a similar thing. Being able to put a complex system
| into a computer and arbitrarily manipulate it still
| doesn't mean we can extract some simple explanation.
|
| On the other end of the scale, see all the AIs coming
| out. They're 100% computer artifacts with theoretically
| no mystery in them whatsoever... but they're just tables
| of billions of opaque numbers and doing anything with the
| numbers beyond just running them is amazingly difficult.
| prasadjoglekar wrote:
| [flagged]
| post-it wrote:
| I'm not super interested in watching Joe Rogan and RFK,
| is there a particular bit where they talk about bikes?
| CSMastermind wrote:
| There's nothing about bicycles in the video he linked.
| post-it wrote:
| A classic Freudian clip.
| mensetmanusman wrote:
| Amazing choice of word. Always check your clipboard links
| before pushing send.
| Guthur wrote:
| Is it RFKs voice? I find it a little difficult to listen
| to as well.
| riversflow wrote:
| I think that is the wrong link?
| hinkley wrote:
| As a bit of an aside, most people don't know how bicycle
| wheels work. There's a whole section in
| https://en.wikipedia.org/wiki/The_Bicycle_Wheel that
| talks about how they actually work. It's not tension at
| the top, it's compression on the bottom.
| denimnerd42 wrote:
| what do you mean it's not tension at the top? did you
| misspeak? bicycle spokes are solely under tensile forces.
| they can't support compressive forces at all. i'm a
| hobbyist wheel builder and a once upon a time
| professional bicycle mechanic during hs & college.
|
| if you want to test this take nearly all the pretension
| out of your spokes and sit on your bike. feel which ones
| are taught and which ones are completely loose. or just
| go to walmart. those bikes hardly have any pretension in
| their wheels.
| hinkley wrote:
| That book I linked has another name, "the wheel building
| bible". Jobst Brandt earned an obituary in Bicycling
| magazine including quotes from his friend Tom Ritchey
| (one of the original mountain bike makers). Jobst was a
| bike fanatic and a mechanical engineer.
|
| Bike spokes are not loose, they're under substantial
| tension. Bolts, I just learned a couple weeks ago, work
| in the opposite way. A tightened bolt compresses the two
| pieces of metal together, and when you tug on them, the
| bolt doesn't stretch more. The tension instead first
| cancels out some of the compressive force on the two
| pieces of metal, before the bolt ever feels more load.
|
| Conversely, all the spokes on the wheel are under
| tension. When you put the wheel on a surface and push
| down, the compression cancels out some of the tension on
| the bottom of the wheel. Cancel out all of the tension,
| and the wheel turns into a potato chip if you don't
| reload it exactly, perfectly on axis. IIRC, none of the
| prior models or theories for how a spoked wheel works
| could adequately explain how potato chipping happens. His
| does.
|
| I used his book to build half a dozen wheels or so and
| the information it contained to fix many more.
| denimnerd42 wrote:
| i own the book.. and also The Art of Wheelbuilding - Gerd
| Schraner
|
| of course in a properly built wheel usually all the spoke
| are under tension...
|
| i was just demonstrating the fact that the spokes on the
| upper half of the wheel are supporting the hub and are
| under greater tension than the bottom ones, the spokes on
| the bottom half of the wheel should remain in tension,
| but only through the fact that they are already under
| tension applied during the building of the wheel.
|
| the fact that the wheel works by tension of the spokes
| becomes obviously apparent when you start to remove the
| pretension and then the spokes will feel loose on the
| bottom half. of course you'd never want to ride a wheel
| like that because it will quickly become out of true..
| just like a walmart wheel.
| hinkley wrote:
| I think one of us needs to reread that book, because he
| emphatically denies that tension at the top of the wheel
| increases. It's tension at the bottom that decreases.
|
| > of course in a properly built wheel usually all the
| spoke are under tension...
|
| No, a properly built wheel all of the spokes are always
| under enough tension you can bounce a penny off them.
| Always.
| denimnerd42 wrote:
| no. you're assuming the rim has no deflection which is
| untrue. if you build a rim out of schedule 80 steel pipe
| then yea. but 300-400-500g rims on high performance bikes
| do not act like that. the spokes are constantly loading
| and unloading tension as they bash through rocks and over
| jumps. the point is that the pretension on the wheel
| needs to be high enough the spokes do not loosen too much
| under these forces. if they do in fact loosen too much
| the nipples will begin to loosen and unwind and the wheel
| will become out of balance.
| hinkley wrote:
| I'm not assuming the rim has no deflection. What makes
| you think that.
|
| Anyway, this sums it up pretty well. Someone has a longer
| memory than I:
|
| https://news.ycombinator.com/item?id=36891231
|
| If you're talking about twisted spokes unwinding, you
| don't have to reach zero load for that to happen. You
| just need to reduce the load enough so the rotational
| force overcomes friction. Tension will also try to unwind
| a screw as well. But the thread pitch on spokes is very
| fine, which lessens that force. If you build spokes like
| wood screws we would have problems and that has nothing
| to do with reaching 0 newtons.
|
| You can release a lot of those tensions by squeezing the
| spokes mid build. Just don't wait until they're too tight
| to do it. I had a pulse in my rear wheel that probably
| came from doing that wrong the first time. Unless it was
| a factory defect, I must have overtensioned and warped a
| brand new Mavic aero rim ever so slightly. Expensive
| lesson, but it could have been worse.
| [deleted]
| bradyd wrote:
| They even make spokes that are rope
|
| https://berdspokes.com/pages/technology
| hinkley wrote:
| I wonder if those have less or more breakin issues
| compared to spokes. With a spoke you have to reset the
| angle of the bend to the shortest distance between the
| hub and the rim. But with cables they have to settle in
| along their entire length.
|
| Doesn't change the answer. They're still compressing.
| They're just pretensioned.
| wiredfool wrote:
| There's a lot more creep early on, which is compensated
| for by a staged tensioning over the course of a few days.
| They may require the spoke holes in the hub to be
| radiused, which can be a warranty issue between you and
| the hub manufacturer. Windup is controlled by a flat on
| the small bit of spoke used for threads.
|
| They're ok (i.e., made it through Tour Divide with no
| issues), done well they're certainly better than badly
| done steel spokes, but it's not clear if the best builds
| are better than the best steel builds.
| denimnerd42 wrote:
| you sound highly confused, what is compressing? the rim?
| the spoke?
| hinkley wrote:
| You need to reread Brandt.
|
| There are two situations when you can push on a string.
| One is when it's frozen, and the other when it's
| tensioned. How do you unload a bow string? You push it
| off the notches.
| denimnerd42 wrote:
| bro. you're wrong. just build a bicycle wheel some time.
| it becomes very obvious how they work as you take it
| through the various stages of tensioning.
| hinkley wrote:
| Why do you think someone would talk about Brandt's work
| if they hadn't used it?
|
| I've built more than half a dozen bicycle wheels. My set,
| my spare that my brother road (into the ground - my first
| set and practically the only problematic ones, but he
| road over bumps without getting out of the saddle), a set
| my dad commissioned from me, and a pair that he had me
| build for a friend. All by age 17.
|
| I then worked as a mechanic for two summers of college. I
| was never the fastest, but if we had a customer we could
| not afford to disappoint, I or the senior mechanic got
| the job because my repairs did not come back.
|
| I saved three or four wheels that would have been scrap
| by unwinding the spokes halfway and building it back up
| again like a wheel build. Only added an extra ten or
| fifteen minutes but it works a charm. When a good
| customer comes in on Wednesday before an out of town bike
| ride you can't afford to fuck it up. I think I only built
| a couple professionally, and usually singles. That's a
| lot of labor and few will pay.
| wiredfool wrote:
| This dialogue is reminiscent of rec.bycycles.tech
| arguments with Jobst, ca 1993.
|
| A bike wheel is a linear elastic system, that can be
| thought of as a superposition of a uniformly set of
| tensioned spokes as one state, and a set of spokes in
| compression in the loaded zone (bottom of the wheel) as
| the other state. So long as the superposition of the two
| states obeys the limiting conditions (i.e. spokes in
| tension) they can be analysed separately.
|
| The size of the loaded zone is related to the relative
| stiffness of the spokes (axial) and the rim (bending),
| and can be calculated using beam on elastic foundation
| methods. For typical rim/spoke combinations, this is
| approximately 4 spokes.
|
| Outside of the loaded zone, spoke tensions essentially
| don't change.
| hinkley wrote:
| And thread. Thereby proving my point: Almost nobody knows
| how bicycle wheels actually work.
| IshKebab wrote:
| Nah they both understand it. One of them is just arguing
| to show off.
| sslayer wrote:
| The real winner will be who comes up with application for
| LK-99 to improve bicycles
| hinkley wrote:
| Electric bicycles baby.
| denimnerd42 wrote:
| Well. I wish we could sit in front of a bicycle wheel and
| discuss it. Because I have a feeling we are shooting
| arrows at different targets. As a mountain biker I'm more
| interested in what happens when an extreme amount of load
| is applied to the wheel, not the model with assumptions
| applied. Definitely a difficult concept to discuss with
| only text. Anyways.. glad to have a good discussion with
| you about bicycle wheels. Don't find many people like
| you. :)
| hinkley wrote:
| I think I would have been a mechanical engineer if I were
| born 20 years earlier or 20 years later. Software was
| just new and shiny enough and it let me build things with
| my mind, at a time when I believed I was clumsy (I
| actually have always had excellent fine motor skills,
| it's macro motor control I lagged behind in). One of my
| better friends in college was an ME. Learned all sorts of
| things about metal fatigue and oddly enough picosecond
| lasers from him.
|
| I don't know if I found Lego or Lego found me, but I
| definitely think in terms of shapes. I was past my
| midlife crisis before I realized that I don't have a
| large working memory (smaller than average in fact) it's
| just that I've been doing mind palaces without pictures
| since I was very small. When I'm thinking of large
| computer systems I'm essentially thinking of them as
| physics problems.
|
| I really should figure out space to have a bike again. I
| never rode when I lived in Seattle (Seattle drivers are
| nuts) but I don't live there anymore and I need to catch
| up on 20 years of tech.
| wiredfool wrote:
| I think you're both in violent agreement using different
| terms.
|
| You're looking at the macro "It's all in tension"
| (superposition of two states) and hinkley is looking at
| the "bottom is a compressive change" (dynamic portion of
| the load).
|
| What I'm not clear of is if you think that the upper
| spokes change tension between the unloaded case and the
| plain gravity load case (force on hub down, ground on rim
| up at the bottom), or if you expect the top half spokes
| to increase and the bottom half to decrease in tension. I
| think this is what hinkley thinks you think.
| hinkley wrote:
| That was indeed my interpretation of that half of the
| conversation. That they were claiming that the axle is
| suspended (tension increases with downforce) by the
| spokes above the midline of the circle, which is what
| Brandt vehemently contended was false.
| hinkley wrote:
| Hey do you happen to recall, did Brandt prove this theory
| with a tensiometer or did I just hallucinate that?
| wiredfool wrote:
| Pretty sure he did, but I don't have r.b.t. archives. He
| was definitely a proponent of them, preferred a specific
| brand/style, and would have easily been able to do the
| experiment.
| matsemann wrote:
| Not to appeal to authority, but I wrote my thesis on
| bicycle wheels. You got it the wrong way around.
| hinkley wrote:
| And have you read Brandt's work?
|
| https://news.ycombinator.com/item?id=36891231
|
| The world is full of papers that are wrong. Including
| maybe the one this whole thread is about. It's okay, it
| happens. Science doesn't find right or wrong, though a
| lot of people think so. It finds more wrong and less
| wrong.
| SkyBelow wrote:
| I'm assuming they mean the balance mechanism, and
| specifically what allows us to balance. How much is it
| the rider shifting their weight, how much is micro
| steering adjusts as we move forward, how much is the
| gyroscopic forces of the wheels, how much of it has to do
| with the angle of the handle bars to the wheel verse the
| center of weight.
|
| That said, I'm guessing this one is well understood by
| experts, but more complex than someone would assume at
| first glance, and many who have some understanding likely
| have an incorrect or at least incomplete understanding of
| how balancing works.
| reaperman wrote:
| We have self-balancing bicycles. We clearly know it well
| enough to replace the human with a computerized machine.
|
| Maybe we don't know how humans use the bicycle but we
| know how bicycles balance, we can write programs to
| balance them physically.
|
| 0: https://youtu.be/Ya7iacmVjUM
|
| 1: https://youtu.be/2Z67NkvXIF4
| acters wrote:
| You are correct, a lot of forces are canceling out on the
| long term(instead of instantaneously) it can easily be
| manipulated into increasing periods of unbalance in one
| direction until a point is reached then a separate
| mechanism is used to force it to a balanced state.
| Conservation of energy is always in effect. Gyroscope
| effects that bike wheels can be added with other separate
| gyroscopes. Thus, a self righting bike. The effect called
| precession is understood well enough.
|
| How a human is able to manipulate it is simply by using
| the force of gravity from shifting their weight(moving
| the center of gravity). However, the movement of the
| center of gravity has to be perpendicular to the wheels
| axle. The steeper the angle of attack the wheel has to
| the ground, there will need to be an exponential increase
| in distance to move the center of gravity. Once the wheel
| is parallel to the ground, there will be an undefined
| distance needed to move the center of gravity.
| BizarroLand wrote:
| I wonder what learning the specific system by which bikes
| are balanced would teach us about the world or human
| beings?
|
| It's such a banal thing to be so fascinating.
| hinkley wrote:
| We don't know until we know.
|
| The smart phone is the culmination of understanding a
| million facts about materials sciences (applied and
| theoretical), some of which were obvious, some of which
| were non-obvious. Starting from a transistor you could
| see from across the room down to ones you can't even see
| with a magnifying glass.
| doctorwho42 wrote:
| It's the reason I got a degree in physics, if you have
| good professors - discussions like this cause you to
| break down the problem quite quickly in your head in a
| working model. Think force diagrams, but with a ton more
| math backing it up.
|
| I actually find the ice skate a better example than a
| bike. We have all the physics solved for bikes, it's a
| complicated system but so is everything in motion. Hence
| we assume a spherical cow for the sake of the problem.
|
| But ice skates... Now that's a funky one. Why do ice
| skates works? Ice skates aren't sharp bladed, they
| actually have flats. Ice is not slippery, it's when
| something is on ice in between our shoes and the ice that
| cause it to be slippery. Some people think it's the
| localized pressure of the blade that causes ice to
| locally melt. Hard to really wrap your head around. But
| it works :)
| jibe wrote:
| _Ice skates aren 't sharp bladed_
|
| Not sure how you meant that, but ice skates are sharp.
| Each edge of the blade is sharpened by grinding a hollow
| out of the center.
|
| https://weekendwarriorshockey.com/how-sharp-should-my-
| skates...
| ezconnect wrote:
| I thought it was not just about ice skating but the
| question of why is ice very slippery is the hard part to
| explain.
| SkyBelow wrote:
| >We have all the physics solved for bikes, it's a
| complicated system but so is everything in motion. Hence
| we assume a spherical cow for the sake of the problem.
|
| This depends upon the question one is trying to answer.
| If one is trying to create a bicycle that can self
| balance, that involves considering different factors
| compared to trying to determine why certain injuries
| result in a person losing the ability to balance on a
| bicycle while others do not. Is the focus the bicycle or
| the human?
| dllthomas wrote:
| Do we know whether the mechanism was proposed before or after
| observing the results? If they found the material because of
| the theory, then I think it's very relevant.
| gus_massa wrote:
| Somewhat similar compounds are superconductors, so it's
| possible that a wrong theory gave them a lucky hint to
| modify an old superconductor into the new superconductor.
| beowulfey wrote:
| Someone who speaks Korean may have to go through the
| original paper. It is LK-99 though; I wonder if they tried
| 99 other combinations first!
| stu255 wrote:
| No,
|
| Lee and Kim first discovered the material in 1999 and
| have spent 20 years doing other things in between getting
| help to figure out how to isolate LK-99 and reproduce the
| correct grain structure.
|
| They eventually got a world class physical chemist, Kwon.
|
| There is now a huge bust up within the team, hence the
| muddled race to publish and claim credit.
| beowulfey wrote:
| Ahh that makes sense. I was wondering what was going on
| with the two papers and thought it might be something
| like that too. Thanks for the extra details.
| scarmig wrote:
| Yeah. BCS was proposed a half century after the first
| conventional superconductor was discovered, and even today we
| don't have a convincing mechanism for "regular" high-Tc
| superconductors. But if it superconducts, it superconducts,
| and research into the how is useful but not a blocker to
| using it.
| bluGill wrote:
| That depends. If it super conducts, but it isn't useful in
| the real world, then we will be waiting for theory to -
| hopefully - give us some insight into how to improve things
| to useful.
|
| This only can carry a small amount of current. I'm not sure
| how to figure out what small means (numbers are given in
| the article if you know how to use them!), but if the
| losses using regular wire are less than the energy needed
| to make this stuff then it isn't useful.
|
| This is made out of lead. Even if it is useful for
| transmission, the difficulty of working safely with lead in
| a factory may mean it is impractical. Or it make leach lead
| into the real world making it not safe to deploy.
|
| There are probably other ways this can turn into a "it
| works but isn't practical" thing that would force us to
| wait for theory (or luck!) to point to something better.
| What I wrote above is what I can think of in a couple
| minutes. Only time will tell though, I hope it works out.
| phyzome wrote:
| Unfortunately, most companies seem to have little
| compunction about exposing workers, consumers, or the
| environment to toxic materials. The use of lead is not in
| any way a blocker, for better or worse.
| OfferFun6595 wrote:
| It seems a 50/50 situation so long as the lead is able to
| get the products most companies don't seem to bother a
| lot about the risks of this exposure
| pzber wrote:
| 250 milliamps still sounds great for use in antennas.
| reaperman wrote:
| > If it super conducts, but it isn't useful in the real
| world, then we will be waiting for theory to - hopefully
| - give us some insight into how to improve things to
| useful. This only can carry a small amount of current.
|
| Thank you for this.
|
| > This is made out of lead. Even if it is useful for
| transmission, the difficulty of working safely with lead
| in a factory may mean it is impractical.
|
| Have you been to a hardware store lately? A huge amount
| of pipe fittings for gas and non-potable water are made
| from lead. Factories don't find it hard to work with
| lead. It might be inadvisable but it's not hard.
|
| We can argue about the "working safely" part, but in
| terms of "does this make it impractical?" the answer
| seems to be no under the current global regulatory
| environment.
| beepbopboopp wrote:
| [flagged]
| mlyle wrote:
| Nah. We have a reasonable understanding of fluids. It's
| just that the two things we say as simple explanations
| (the plane pushes air downwards causing an equal and
| opposite reaction to push the plane up; faster flow on
| top of the wing "sucks the plane upwards") are both only
| partial truths.
|
| Sometimes you get arguments between partisans for each of
| these two simplified explanations, but really both are
| bogus.
| cooper_ganglia wrote:
| In the Vsauce video "Do Chairs Exist?" (I highly
| recommend it!), Michael talks about the concept of
| vagueness and how defining boundaries can lead to
| paradoxes. While it was primarily dealing with an
| ontological perspective, the linguistic perspective of a
| particular line has always stood out to me. Perhaps it
| makes a bit more sense in context of the full 40-minute
| video, but it is:
|
| >"Composites are causally redundant. Believing in chairs
| is like believing that, while yes, the burning gas from
| my stove completely describes why the water in a pot
| boils, there's ALSO a magical invisible substance called
| boil-o that comes out of my stove that does the same
| thing as the flame at the same time, and if there was no
| boil-o, the flame would warm the water just the same, but
| there IS boil-o... Chairs are no more real than boil-o.
| Composites over-determine what happens in the world."
|
| Like your example with lift and fluid dynamics, simple
| explanations like "plane pushes air downwards" or "faster
| flow sucks the plane upwards" might be insufficient, but
| they're at least useful to the layman. It also reminds me
| of how Richard Feynman answered the question, "What is
| the feeling between 2 attracted magnets?" by explaining
| that it would be impossible to give a complete answer.
| Feynman pointed out that when you ask why two magnets
| attract each other, there are different levels of
| understanding depending on your background knowledge. For
| someone with no knowledge of physics, the simple
| explanation would be the existence of a magnetic force
| causing the attraction. However, delving deeper into the
| question raises complexities that can be challenging to
| explain.
|
| Feynman highlighted the difficulty of answering "why"
| questions in general. Explaining magnetic attraction in
| terms of something else that we are more familiar with,
| like rubber bands, would be misleading and circular, as
| it ultimately comes down to electrical and magnetic
| forces. He acknowledged that some aspects of the natural
| world may need to be accepted as fundamental elements
| without a more profound explanation.
|
| This is echoed in the Vsauce video, where defining
| boundaries and attempting to explain everything can lead
| to paradoxes and vagueness. The concept of "boil-o"
| illustrates how composites, like chairs, can over-
| determine what happens in the world and our own
| perception, making their actual explanation even more
| elusive.
| didgeoridoo wrote:
| I've never understood how this battle could possibly
| persist, considering that _planes can fly upside-down_.
| The fact that Bernoulli's Principle creates a low-
| pressure zone on the top of the aerofoil just gives you
| laminar flow at higher angles of attack.
|
| It really isn't that mysterious, unless you insist that
| only a single physical law is allowed to come into play.
| mlyle wrote:
| > I've never understood how this battle could possibly
| persist, considering that planes can fly upside-down.
|
| That's orthogonal. Planes flying upside down still have
| air flowing faster over the new "top" of the wing than
| the bottom.
|
| Though, a common misunderstanding is that air must be
| taking the same "time" to go over the top and the bottom.
| This is not true.
|
| You can build a pretty good mental model of flight with
| either simplified mechanism, but you end up
| underestimating performance by a fair bit.
| blagie wrote:
| > You can build a pretty good mental model of flight with
| either simplified mechanism, but you end up
| underestimating performance by a fair bit.
|
| I've never hear of a good mental model built on
| Bernoulli's Principle. They are either:
|
| - Wrong
|
| - Give no intuition
|
| The key question is /why/ air moves faster on one side,
| and once you get away from the misconception of same
| time, I've never heard an intuitive argument.
|
| Redirecting air down:
|
| - makes complete sense
|
| - can be demonstrated by sticking your hand out the
| window of a car
|
| - works with flat airfoils (sails, kites, etc.), and
| explains those well too
|
| And the shape of the wing comes in from wanting the
| leading edge parallel to incoming airflow, and the other
| edge parallel to outgoing airflow. On a sail, I can
| adjust the shape. On a steel wing, I can't much, so I
| make a shape which works across different angles of
| attack.
|
| All of the other mechanisms, you can gradually work in
| from there to get accurate models. Toss in air moving to
| the low-pressure area, and having momentum, and you get
| why helicopters are less efficient than planes, as well
| as vortex shedding. It all builds up.
|
| As a corollary, Bernoulli tells you where air moves
| faster, but that follows from lift. Not the other way
| around. At least in any model which fits the human brain.
| ddalex wrote:
| Why are you benchmarking models to human intuition? If
| you apply the same reasoning to quantum mechanics you'll
| have a bad time.
|
| I'm sure models can accurately compute how much of the
| wing lift comes from the suction effect on the top of the
| wing versus the push on the bottom of the wing.
| blagie wrote:
| Because it's literally what I'm responding to:
|
| "You can build a pretty good mental model of flight with
| either simplified mechanism"
|
| For computational models, neither of these are great
| starting points. When I last looked, finite element
| methods were where the action was.
|
| And if you don't apply the same to quantum -- looking for
| intuition -- you'll have a bad time. Quantum computing
| algorithms came from human insight.
| Linosaurus wrote:
| > The key question is /why/ air moves faster on one side,
| and once you get away from the misconception of same
| time, I've never heard an intuitive argument.
|
| Since the air follows a curved surface instead of
| straight ahead, you could perhaps apply your intuition
| for centrifugal force. Momentum sort of pulls the air
| away from the surface.
|
| I'm not even sure this explanation is wrong.
| blagie wrote:
| That's interesting.
|
| Counterpoint: A wing with the opposite curvature would
| work too, just much less efficiently. Your explanation
| has an element of truth, but an element of untruth. It'd
| take more analysis to tease them apart.
| cornel_io wrote:
| We 100% know why airplanes of every shape and size stay
| aloft, and can calculate lift/drag extremely accurately
| based on the geometry of the plane and the airflow, in
| both steady state and much worse conditions. We have
| great approximations for steady state that make perfect
| sense and simplify the situation greatly and make it more
| understandable without simulation, even if they gloss
| over some details.
|
| Where are you getting this terrible information that we
| don't know how flight works? Have you ever talked to
| literally anyone who has worked in aeronautical
| engineering, or even studied the basics of fluid
| dynamics?
| VagabundoP wrote:
| Yeah, but what about Bumblebees.
|
| Yeah, didn't think so. ;)
| MattPalmer1086 wrote:
| They figured that one out too... Something to do with
| vortices...
| VagabundoP wrote:
| Yeah I was being sarcastic. Forgot the /s. :(
| littlestymaar wrote:
| > This is made out of lead. Even if it is useful for
| transmission, the difficulty of working safely with lead
| in a factory may mean it is impractical. Or it make leach
| lead into the real world making it not safe to deploy.
|
| Lead is still routinely used in many applications today,
| either in metallic form, from ICE car batteries, to
| fishing or hunting gear, or as chemical compound in
| different kinds of glass. And the same can be said about
| other heavy metals like Cadmium or Mercury. Industries
| also routinely work with much more nasty things than
| lead, so it really doesn't sound like a show-stopper.
| scythe wrote:
| In particular, lead is still extremely common in
| radiation shielding, possibly because the drop in demand
| for other applications made it so cheap. Lead-lined
| drywall is the default approach for setting up a
| radiography, fluoroscopy or CT suite.
| thayne wrote:
| > possibly because the drop in demand for other
| applications made it so cheap
|
| Maybe a little bit. But I think it is more that it is a
| material with heavy atomic nuclei and high density, and
| thus effective at blocking radiation. And it is also
| relatively cheap.
| scythe wrote:
| Lead is absurdly cheap. One dollar a pound! Cheaper than
| much more common metals like aluminum or magnesium. So I
| diagnose a low demand.
|
| They used to talk about using barium cement but it just
| can't compete, price-wise.
| shirleyquirk wrote:
| It may not come as a complete surprise that the economics
| of metals are more complex.
|
| Aluminium, was so expensive until the Hall/(that other
| guy) process was developed, that it was used for
| jewellery [1].
|
| Even today it's expensive and difficult to reduce Al ore
| to metal, which is a supply side problem.
|
| [1]https://www.bellandbird.com/products/aluminum-bangle
| rob74 wrote:
| TIL! Aluminium is an extremely useful metal, but I would
| never have thought it would be used for jewelry - I mean,
| it's not enough for the metal to be expensive, it also
| has to look and feel desirable, which soft and dull
| Aluminium definitely doesn't. If you have ever held
| Aluminium cutlery in your hand, it just feels cheap
| compared to stainless steel (not to mention silver).
| bluGill wrote:
| Today it isn't used for jewelry. 200 years ago it was -
| not so much to wear, but to show off that you were rich
| enough to afford it. Only royalty could afford things
| made out of aluminum.
| stu255 wrote:
| 75% of aluminium supply is from recycling aluminium
| products.
|
| The economy sort of has a "working capital" quantum of
| aluminium which also grows steadily from aluminium
| mining.
|
| Lots of metals have very different and complex supply
| structures and thus completely different $$$ / volume
| curves for their supply.
|
| Understanding the $$$ / volume curve of commodities is
| not something that is commonly considered when people try
| and predict the future. Mining a billion tonnes of
| Aluminium from an asteroid for example and safely landing
| it on Earth can never be profitable because the $$$ /
| volume curve for Aluminium is $0.00 at billion tonne
| volume.
| rob74 wrote:
| Now I'm curious where that recycled aluminium is coming
| from? My guess would be mostly from airplanes and
| beverage cans...
| tonyarkles wrote:
| Engine blocks too. If you go to a scrap yard though
| you'll be pretty amazed at all of the stuff they've got
| collected and sorted. Metal recycling (compared to, say,
| electronics recycling or plastic recycling) has a very
| clear economic model and financial incentives. If you're
| demolishing a building or scrapping old machinery it will
| cost significantly less to recycle the metal (because you
| get paid decently by the pound) than to take it to a
| landfill (where you pay by the pound instead).
| et2o wrote:
| I believe that most of the lead used today is a by-
| product or co-product of mining other more valuable
| metals like Zinc and silver. Lead is quite abundant in
| the Earth's crust and found in easy to access deposits.
|
| I think >80% of the current industrial use of lead is for
| batteries. It's probably still in the top ten most mined
| metals by dollar value and definitely by mass.
| salty_biscuits wrote:
| The mineral containing Zinc is called Sphalerite, which
| is based on a greek etymology for "deciever" because it
| commonly occurs with Galena (which has Lead and Silver)
| and looks similar.
| EdwardDiego wrote:
| As a young fella, I carried a lot of that lead-lined
| drywall, it's (obviously) really heavy, and expensive so
| you got yelled at a lot if you damaged the edges,
| couldn't just trim it off like normal drywall.
| burtonator wrote:
| I want ONE breakthrough like this in my lifetime. Something
| completely game changing.
| doctorwho42 wrote:
| Live to see SPARC turn on, there are some pretty smart people
| with models actually showing it breaking Q>3. Turns out the
| hardest part about productive fusion is the sustained high
| compression, and HTC tape really helps increase the
| compression by a large amount. (See their 20 Tesla test at
| the start of the pandemic)
| [deleted]
| kaashif wrote:
| Meanwhile as someone who had to deal with writing code for
| Solaris and using Sun's compiler, I think I've achieved my
| goal by seeing my last SPARC turn _off_!
|
| But yeah, nuclear fusion is cool.
| Helmut10001 wrote:
| Just want to mention for others: The first result for SPARC
| on google is SPARC (Scalable Processor Architecture),
| whereas SPARC (tokamak) [1] is what relates to Q>3.
|
| [1]: https://en.wikipedia.org/wiki/SPARC_(tokamak)
| dgroshev wrote:
| It would be great though if they stopped sponsoring the war
| in Ukraine. Yes it's unfortunate that their main HTS tape
| supplier is Russian, but pretending that it's not and just
| ignoring the issue (or obscuring the supply chain through
| that Japanese middleman) is pretty immoral.
| stu255 wrote:
| Neutron damage is the real filter for fusion.
| arcadi7 wrote:
| Short answer: talk about quantum wells in this context is
| meaningless .
| jpmattia wrote:
| > _They propose that electron tunneling between these quantum
| wells, which are between 3.7 and 6.5 Angstroms apart, is the
| superconducting mechanism._
|
| That is a very strange explanation. As someone who has done a
| decent amount of solid-state physics work, I would expect the
| explanation to involve a mechanism for pairing of electrons.
| Mere tunneling between quantum wells has been a staple since
| the "metamaterials" of the 80s and 90s.
|
| That said, the measured curves do not lie, and I haven't kept
| up with the field. So I'm all ears (and very much hoping the
| superconducting revolution is upon us!)
| dexwiz wrote:
| Are you referring to a Cooper pair?
| aqme28 wrote:
| Yeah, that's the generally used explanation for
| superconductivity
| xeonmc wrote:
| Would it be accurate to describe it as "lattice
| peristalsis"?
| aqme28 wrote:
| That's sort of the proposed mechanism for Cooper pairs
| forming, but I don't think I'd call Cooper pairs
| themselves "lattice peristalsis"
| [deleted]
| 8bitsrule wrote:
| >(SF readers will recall that one such material was a big plot
| point in Larry Niven's Ringworld).
|
| Even the one with (as he put it) 'the mistakes in it' !!
| rohan_ wrote:
| What do the "super forecasters" have to say about this? Was this
| predicted on prediction markets? Was the assumption of this tech
| existing already factored into prediction models?
| hcks wrote:
| Prediction markets say this will probably not replicate (and
| imo even overestimate the probability of replication)
| treme wrote:
| link? interested in this wager
| pallas_athena wrote:
| https://polymarket.com/event/is-the-room-temp-
| superconductor...
| shusaku wrote:
| ~20% of a ground breaking discovery is actually a good
| week in my view!
| amelius wrote:
| Can we just send some current through it and see if it heats up?
| jake_D wrote:
| 1. In the video, they push the disc with a pen until it rolls
| over. They repeat it multiple times. It it were superconductive
| they could just position it in space without laying it on the
| magnets first.
|
| 2. The disc is not hovering.
|
| 3. The disc is damaged; one edge is thicker/heavier than the
| other. Thus causes the rolling. Notice that the heavier part
| always stays on the magnet. It it were superconductive they would
| be able use a uniform disc.
|
| I call BS.
| blablabla123 wrote:
| With a "regular" magnetic field you cannot even do this, it
| would roll over continuously. At least one point needs to be
| actually fixed. Also if I remember correctly it's mentioned
| that not the whole probe is superconductive but just part of
| it.
| jake_D wrote:
| It would not roll over continuously as it's affected by
| gravity as well. The heaviest part is at the bottom.
|
| And if it's not completely superconductive, what stops it
| from not being completely magnetic? For all we know, only the
| thin part could be magnetic, being repelled from the magnet
| below.
| pbj1968 wrote:
| Korean scientists are known for making a lot of bold and
| unreproducible claims.
| simmanian wrote:
| I see a few comments saying this can also be used to "solve"
| climate change, but I am trying to understand the how. Do people
| mean that the world will have less carbon footprint overall
| because everything will be much more efficient?
| XorNot wrote:
| https://en.wikipedia.org/wiki/Superconducting_magnetic_energ...
|
| You build a big inductor, and because it's superconducting
| current just goes round and round. At room temperature you have
| no refrigeration losses, you can build more just as fast as you
| can kick out superconductor. It would be 100% efficient, have 0
| self-discharge, and enormous power capacity and infinite power
| cycles.
| NeoTar wrote:
| I think it may be that electrical power could be generated in
| places where (carbon free) energy production can be abundant
| but consumption is low (e.g. Solar power in the Sahara desert)
| and then transported with almost no losses to sites of high
| energy consumption (e.g. the cities of North Africa and
| Europe).
| BizarroLand wrote:
| North America could be powered with a small section of Nevada
| being covered in Solar Panels, given a theoretical
| transmission loss of only a few percent from one side of the
| country to the next. Bolster that with windmills and
| hydroelectric and that would be that for the next 30 years.
|
| Electricity would be cheaper and more plentiful than water in
| many areas.
| AlexAndScripts wrote:
| A version with higher current would allow us to link the
| world's electricity networks with zero energy loss. That would
| allow us to build out solar panels in a ring around the
| equator, and it would be fine that it was night in some places
| - because we could get power from the panels on the other side
| of the world.
| pshc wrote:
| Even if we replaced all fossil fuels overnight we still
| wouldn't have "solved" climate change--the damage we have done
| is locked in for the long term. We need active mitigation to
| restore Arctic ice, de-acidify the oceans, save coral reefs,
| bring back old weather patterns, etc.
| t3estabc wrote:
| [dead]
| ck2 wrote:
| Oooh fresh Derek Lowe, awesome
|
| Enough of all the UFO nonsense, this is what matters for the
| future
|
| > _If these data reproduce, the superconductivity of this
| material seems beyond doubt._
|
| > _Another welcome feature is that their procedure for preparing
| LK-99 seems quite straightforward. You can bet that furnaces in
| solid-state materials labs around the world have been cooking
| yesterday and today to try to reproduce its synthesis and the
| properties, and we should be hearing about the results of these
| experiments very soon._
| Helmut10001 wrote:
| For those like me that know nothing of superconductivity, I found
| this [1] entry quite helpful to assess the impact, particularly:
|
| > At atmospheric pressure the temperature record is still held by
| cuprates, which have demonstrated superconductivity at
| temperatures as high as 138 K (-135 degC).
|
| [1]: https://en.wikipedia.org/wiki/Room-
| temperature_superconducto...
| curiousObject wrote:
| While we're waiting for experimenters to reproduce this, it's
| worth comparing this amazing announcement to the Cold Fusion
| affair of 1989[1]
|
| It's notable that the first publications about attempts to
| reproduce the Cold Fusion experiment all reported _positive_
| results.
|
| It's probably because experimenters who got negative results
| decided they might have done something wrong so they kept trying,
| and delayed, and they did not publish until later.
|
| Those early reports of positive results were largely retracted
| within a few weeks.
|
| [1] https://en.wikipedia.org/wiki/Cold_fusion
| selestify wrote:
| Why did those early experimenters report positive reports? Did
| they inadvertently do something wrong themselves that looked
| like cold fusion?
| wolfram74 wrote:
| Small effect sizes make it easy to confuse noise for positive
| results. Throw into it the very strong desire to see the
| thing work, and, well, even the best of us are only human.
| curiousObject wrote:
| > Did they inadvertently do something wrong themselves that
| looked like cold fusion?
|
| Yes, probably
|
| This blog talks about some of the many pitfalls that could
| mislead researchers:
| https://coldfusionblog.net/2019/03/13/the-case-against-
| cold-...
|
| Some of the errors are very subtle. It's not surprising that
| mistakes were made
| segfaultbuserr wrote:
| It was a great blog, it was a lot of fun when I found it.
|
| The summary was basically that, designing a reliable
| calorimetry equipment and experiment suitable for use in
| Fleischmann-like experiments is just uniquely challenging,
| it remained an unsolved problem even decades after the
| initial fiasco. The whole experiment setup is inherently
| error-prone. I found it was pretty interesting.
|
| One researcher P.J. King who recently attempted a
| replication [1] commented online [2] that:
|
| > _We observed the claimed heat effect, both in magnitude
| and duration, in our parallel __control__ cells. This
| indicates a calibration error in the apparatus. One little
| known fact about these electro-chemical cell experiments is
| that they are run for a week or more before the effect is
| observed. Typically, calibration is conducted over a few
| hours and is done both before an experimental run and
| intermittently during it, to re-check thermal stability._
|
| > _We submit that this approach to calibration is
| inadequate for establishing a calorimeter's propensity for
| heat artifacts. Stability over time periods longer than the
| experiment should be demonstrated in order to minimize the
| possibility of misinterpreting the fluctuations that we
| observed as "excess heat" events._
|
| > _Consequently, we contend that all claims of anomalous
| heat in LENR experiments using electro-chemical cells that
| do not exhibit thermal stability on a time period longer
| than the time duration of the experiment itself must be
| thrown out. As the majority of research over the past 30
| years has not demonstrated this kind of calibration
| stability, that eliminates most of the effort in this
| field. You can read more about our work on the ReResearch
| LLC website._
|
| > _That is not to say that we know everything about hot
| fusion in the solid state or how quantum mechanical
| interactions might impact fusion reactivity. There is much
| still to be discovered. But these electro-chemical LENR
| heat experiments are noise, not signal._
|
| [1] Guffey, Mason J., Yang Tang, and P.J. King. 2016.
| "Attempted Replication of Excess Heat in the Letts Dual-
| Laser Experiment." Journal of Condensed Matter Nuclear
| Science 20 (1): 1-28.
|
| [2] https://www.youtube.com/watch?v=ZbzcYQVrTxQ&lc=UgzFM3zS
| 0QyP5...
| mcguire wrote:
| IIRC, there were two groups of groups working on it (the
| process was simple enough that a description from the press
| conference was enough to get started):
|
| * people looking for fusion neutrons, who did not have much
| experience with the finickiness of neutron detectors and who
| reported seeing them when they were getting experimental
| errors, and
|
| * people looking for excess heat, which was simply inherently
| difficult to measure accurately.
|
| On the other hand, there wasn't a publication delay for the
| negative reports; within a week the groups started talking to
| each other and realized they weren't unique in not finding
| anything.
| mcguire wrote:
| Gary Taubes's _Bad Science: The Short Life and Weird Times
| of Cold Fusion_ is pretty good.
| kvetching wrote:
| The guys at Falcon Space said they were working on trying to
| reproduce it today - they said they have everything they need.
| This is their channel https://www.youtube.com/@FalconSpace
| where you can learn more about them
| zeronullempty wrote:
| [flagged]
| m463 wrote:
| I remember being interested enough to suspend disbelief for a
| little while with rossi's e-cat:
|
| https://en.wikipedia.org/wiki/Energy_Catalyzer
|
| nothing happened, of course, but the idea of an elegant energy
| source was so seductive.
| gus_massa wrote:
| The experiments with the e-cat were measuring temperatures
| and estimating heat flow of the hot air flowing arround the
| device. That's too difficult to do acurately.
|
| If you see a report of a groundbreaking experiment that only
| measure the heat of the air, you can safely press the "meh"
| button.
| dtgriscom wrote:
| I miss Cold Fusion. What a wonderful idea. It's a shame reality
| didn't cooperate.
| perihelions wrote:
| Another example of this was Millikan's determination of the
| fundamental electric charge (of one electron). The first,
| famous experiment had a major error; and subsequently everyone
| who independently replicated the experiment, for two decades,
| came up with the same error, in the same direction. The people
| whose experiments got the _correct_ value probably self-
| selected themselves out of publishing it.
|
| https://en.wikipedia.org/wiki/Oil_drop_experiment?useskin=ve...
| ( _" Millikan's experiment as an example of psychological
| effects in scientific methodology"_)
| IX-103 wrote:
| It is interesting to note that while the error was in the
| same direction, the magnitude of the error decreased in
| subsequent studies. No one expects to get exactly the same
| result, so there was room for variation towards the true
| result.
| Analemma_ wrote:
| Room-temperature superconductors have so many urgent
| commercial uses that if this fake, I doubt the error will
| persist for that long. There's too much at stake.
| cryptonector wrote:
| Boiling-water-temperature superconductors. Pinch me, it
| feels like a dream.
| mrguyorama wrote:
| There's also probably a hundred labs skipping over
| replication completely to try and beat someone else out on
| a random permutation of these materials and methods and
| hoping to get lucky.
| gus_massa wrote:
| Yes, "replication" in this experiments usualy means
| foloeing the oficial recipe and many small variants.
|
| Publishing an exact reproduction is difficult, but a new
| record a few degrees hotter is easy. (And even another
| variant with a lower temperature and more tolerance for
| current or magnetic field can be published with the right
| text.)
| jacquesm wrote:
| > but a new record a few degrees hotter is easy
|
| Assuming one exists. Assuming it is real.
| gus_massa wrote:
| Yep. Easier to publish, assuming it exist and you can
| find it.
| lolc wrote:
| I can't see why they'd skip replication given the
| uncertain status of the original process. They'd try to
| replicate as closely as possible, confirm they have a
| superconducting material, then they'd branch out from
| their established process. Starting from a variation
| means they don't know whether it doesn't work because of
| the variation or because it doesn't work at all.
| curiousObject wrote:
| That's not unreasonable, but the high-risk, high-reward
| approach would be to let researchers elsewhere do basic
| verification, while you try to leap a step ahead of them
| by going directly to derivative variations.
|
| Abandon the work if nobody can replicate LK-99 within a
| few weeks and you haven't really lost out badly.
| stu255 wrote:
| I hear some very clever labs can do more than one thing
| at a time.
| fbarred wrote:
| If this is real, what about this discovery that made it happen
| now?
|
| Is it a case that some technology is now available that unlocked
| this? Or is this trying something and seeing if it works?
|
| Could this discovery have been made 10-20 years ago?
| jeepers6 wrote:
| COVID.
| terafo wrote:
| It could've been made not only 10-20 years ago, but, probably
| even 100-200 years ago(sure about 20th century, not really sure
| about 19th).
| RyanAdamas wrote:
| What if the team itself did create LK-99 that is a
| superconductor, but they aren't able to reproduce it and only
| have the sample left that works. Hence, they aren't able to make
| more of it to prove their success, but rather decided to release
| the paper and method so that others can try to reproduce it.
| Given the amount of interest, they could put hundreds of labs to
| work trying to recreate what they themselves can't, hoping
| someone will find what they found and have an actual process for
| doing so?
|
| Is that even possible?
| PawgerZ wrote:
| I have never worked with super conductors, but I did talk with
| people who have and read every comment on hacker news. From
| what I can gather, people already make YBCO superconductors in
| their garage, and this doesn't seem much different in
| difficulty. Many people have said that it's simple enough that
| they expect youtube tutorials on how to make it in a week or
| two.
| MVissers wrote:
| The most likely explanation based on the authors in the two
| articles is infighting, where one researcher decides to publish
| an uncomplete manuscript with his name as the third author.
|
| He's omitted from the second author.
|
| I do believe they believe they have something nobel-prize
| worthy.
|
| They offered to help with replication in other labs, which is a
| good sign.
|
| Could still be measurement error, we just need to wait until it
| gets replicated.
| mromanuk wrote:
| How long does it take to get a replication? I would love to
| follow up this kind of news, directly from a the researchers
| doing the work. Is there anyone to follow on twitter to keep
| posted on this?
| valine wrote:
| I believe it needs a minimum of 48 hours in the furnace. If
| labs started right away after the paper hit Arxiv we should
| be hearing about results soon.
| [deleted]
| eig wrote:
| This video (https://sciencecast.org/casts/suc384jly50n) showing
| the Meissner effect should be the easiest to replicate: just send
| a sample to another lab and put it over a large magnet.
|
| As far as I know, the only explanations for this occurring is
| room temp superconductivity, or a strong diamagnetism (which
| would also be very cool to see)!
| ortusdux wrote:
| That video reminds me of the way pyrolytic graphite floats on
| strong magnets.
|
| https://scitoys.com/scitoys/scitoys/magnets/pyrolytic_graphi...
|
| https://youtu.be/Wk3seHNmNs8
| zbobet2012 wrote:
| As far as I am aware you need multiple magnets to make this
| happen, just one will cause it to "fall" off. In the video
| it's just one magnet, and it doesn't try to "slide" away when
| it's moved past the edge of the magnet. That's a strong
| indicator of quantum locking.
|
| I am not an expert in this field though.
|
| https://www.imagesco.com/magnetism/graphite-levitation-
| kit.h...
|
| https://scitoys.com/scitoys/scitoys/magnets/pyrolytic_graphi.
| ..
| SiempreViernes wrote:
| They don't show the actual field of the big metallic
| cylinder, so you can't rule out a situation as shown at the
| start of this video: https://youtu.be/D-tW8_SRW3g where two
| identically looking objects are revealed to have very
| different magnetic fields.
|
| Whether it makes sense to say the multipole magnet is
| "multiple magnets" is a philosophical debate in itself.
| littlestymaar wrote:
| The common point being that it levitates, at room temperature
| (so no cryogenic fumes on the video), but that's exactly what
| you'd expect from a room-temperature SC... The big difference
| between your graphite video and the one from yesterday is
| that the later doesn't move, whereas the former never rests.
| XorNot wrote:
| The problem with the video we see is that the sample never
| actually levitates - one side is touching the magnet. So a
| regular diamagnetic material, with enough weight on one
| side, would display the same effect.
|
| In this video shortly after this moment you see something
| _very_ similar looking with pyrolytic carbon:
| https://youtu.be/VC3r9-OaWes?t=133
| eig wrote:
| Yep, that's strong diamagnetism.
| scythe wrote:
| It's true that pyrolytic graphite does this, but it's also
| worth noting that pyrolytic graphite is one of a _very few_
| materials that has such a strong conventional diamagnetism:
| the list includes pyrolytic graphite and metallic bismuth and
| ends there. I have actually searched the literature for such
| materials on a few occasions simply because they seem like
| they would make a fun decoration, and PG (and "highly
| oriented" PG) is pretty much the only one (bismuth is too
| dense).
| mitthrowaway2 wrote:
| Definitely. Discovering another material besides pyrolytic
| graphite that exhibits strong enough diamagnetism to
| levitate wouldn't get your name in the history books like
| room-temperature superconductivity would, but it would
| already be a major career-making discovery, with at least
| enough commercial value to launch a niche company. It would
| be very strange to tarnish your reputation with fraudulent,
| easily-refuted claims of superconductivity if you've
| already achieved such a breakthrough.
| soligern wrote:
| I don't know enough about this but shouldn't the entire
| superconductor be floating above the magnet? Why is one part
| still attached (or maybe attracted) to the magnet?
| NegativeLatency wrote:
| Contamination/impurities or something else in it that's not
| superconducting?
| soligern wrote:
| A strange exposition video then, I would try to remove the
| part that wasn't superconducting (the part touching the
| magnet) before I released this. A completely floating piece
| of this superconductor would remove literally all doubt.
| xeonmc wrote:
| You say to do WHAT to the best piece of sample they
| synthesized?
| XorNot wrote:
| Scope of the claim. This is world changing. Shoot the
| first video, then get the dremel/pliers and cut that
| large bit off. It would be worth it, because if this
| works at all, then it's vital to prove it. We'd be having
| a very different discussion if that small piece was
| umabiguously floating and remaining locked in place.
| yreg wrote:
| > it's vital to prove it [asap]
|
| Is it? What do they care if it takes other labs a week to
| reproduce?
| Filligree wrote:
| But you don't understand, people are being skeptics on
| the internet.
| petsfed wrote:
| Based on what I'm hearing, it sounds like they weren't able
| to produce a macroscopic ingot of the stuff, so it seems
| likely _to me_ that the superconducting part is up at the end
| there. However, without further explanation, I 'm disinclined
| to take that video (fantastic as it seems) to be conclusive
| evidence of anything.
| rsfern wrote:
| The original preprint mentions bulk samples, but I'm not
| sure what size they were. I would guess at least a few
| millimeters scale, but really bulk just mostly means "not a
| thin film"
| petsfed wrote:
| As an undergrad I helped with research on quasars, where
| reasonable precision was solar mass orders of magnitude
| and tens of parsecs, and the periodic table was Hydrogen,
| Helium, and "metals". Then I switched to condensed matter
| physics for grad school, where "bulk" meant "a scale
| visible to the naked eye under very good conditions".
|
| The dichotomy makes me laugh.
| t3estabc wrote:
| [dead]
| JacobAldridge wrote:
| I'm reminded of the paper, just over 10 years ago, that reporting
| measuring neutrinos travelling faster than the speed of light.
|
| When published, the authors made it clear: this is probably
| wrong, but we can't see where we made a mistake ... so what if
| we're right and just upended relativity theory?
|
| That was turned out to be a measuring error [1]. This one may be
| the same, though the lead authors publishing two versions of the
| paper - one with only 3 names, ostensibly because the Nobel Prize
| can only be awarded to a maximum of 3 people - suggests less
| modesty and vulnerability on their behalf.
|
| I hope they're right though!
|
| [1] https://www.nature.com/articles/nature.2012.10099
| willis936 wrote:
| I don't see the similarities. This upends zero theories. I see
| similarities in the long line of "STP superconductors for real
| this time!" claims, but not findings that contradict current
| physical models.
| bhaak wrote:
| Isn't it that this would upend zero theories because we don't
| have any that satisfyingly explains superconductivity?
| lIl-IIIl wrote:
| I thought of that too, but the difference is that faster than
| light travel is impossible according to our understanding of
| physics, but nothing says that room temperature superconductors
| are impossible.
| [deleted]
| thepaulthomson wrote:
| Can't wait to be flying my car to work
| ryzvonusef wrote:
| https://twitter.com/alexkaplan0/status/1684622263339884544
| > I have bad news. I am growing increasingly convinced that LK-99
| is simply diamagnetic, rather than superconducting. It lines up
| well with existing evidence (susceptibility, levitation, lack of
| heat capacity singularity, etc.)
|
| https://twitter.com/alexkaplan0/status/1684622265403465728
| > Discovering a new diamagnet is cool, but .... obviously way
| less cool
|
| ____
|
| reminded me of this asianometry video on a similar much hyped
| korean breakthrough in biology, and the sad aftereffects of it
|
| https://www.youtube.com/watch?v=c0MMtKMTjoU
| nimish wrote:
| Given the ingredients have known semiconducting properties one
| would think they'd run it through the wringer to expel any doubts
| as to its superconducting properties. 2DEGs and such at room temp
| are common, GaN transistors do it and they have well known
| temperature dependent resistance characteristics.
|
| The semiconductor characterization people at any fab could really
| get to the bottom of this.
| 1-6 wrote:
| Is it Lee or Kim? LeeKim-99
| jeepers6 wrote:
| They were working on this as far back as 1999.
| iceflinger wrote:
| "this stuff is claimed to superconduct all the way up to room
| temperature and indeed up past the boiling point of water. Its
| critical temperature is said to be 127C"
|
| Would this have implications about possible efficient methods of
| converting heat back into electricity? Or even just more ways of
| harnessing heat energy in general. I'm imagining heat pumps built
| with superconductors could be a critical part of mitigating
| climate change, but I'm far from a scientist and barely
| understand the physics here.
| ayakang31415 wrote:
| No, it just means that the material conducts electricity
| without losing almost any energy through heat at that critical
| temperature. Heat itself is a process of energy transfer (heat
| itself is not energy which many people fail to recognize if
| they haven't studied thermodynamics thoroughly).
| etiam wrote:
| Thoroughly upvoted and discussed "The first room-temperature
| ambient-pressure superconductor?"
| https://news.ycombinator.com/item?id=36864624 has barely fallen
| to second page yet, but as the topic is of exceptional interest,
| and under development, and Lowe's commentary is usually welcome
| and well received on HN, maybe some duplication can be justified
| in this case?
| yreg wrote:
| I would welcome a new thread to be honest since it's very
| difficult to find the new comments in this one.
| orblivion wrote:
| So what kinds of cool stuff could be built with a room
| temperature superconductor? Better levitating trains?
| [deleted]
| ianmcgowan wrote:
| From the article,
|
| "Who knows what could come out of that? Robust high-current-
| density room-temperature superconductors are right out of
| science fiction (SF readers will recall that one such material
| was a big plot point in Larry Niven's Ringworld). Electrical
| generation and transmission, antennas, power storage, magnet
| applications (including things like fusion power plants),
| electric motors and basically everything that runs on
| electricity would be affected. We could stop throwing away so
| much generated power on heating up the wires that deliver it,
| for starters."
| [deleted]
| swader999 wrote:
| Nuclear fusion much easier, quantum computing, lossless
| electricity transmission, insane batteries. Dirt cheap MRIs,
| Basically welcome to the Jetsons. Much easier to mitigate
| climate change to the point where we can just deal with it.
| krastanov wrote:
| Room temperature superconductivity does not help with quantum
| computing. The transmons or atoms or ions need to be cold so
| that they do not get "flipped", not because of the need for
| superconductors.
| bick_nyers wrote:
| Do quantum computers not have a need for strong magnetic
| fields? Or is the magnetic field requirement weak enough
| that it can be serviced by non-superconducting magnets?
| sudosysgen wrote:
| The computer needs to be super cold anyways so you might
| as well use a regular superconductor.
| NotYourLawyer wrote:
| This would only solve one of the more minor problems with
| fusion. And what would it do for batteries?
| willis936 wrote:
| The challenge of fusion is a collection minor problems that
| add up to machines that are unviable for our current level
| of industrial output. Eliminating one of the three key
| plant systems (cryo, vacuum, and heating) is not a
| molehill, especially when it is the second highest user of
| power (after heating).
| p_l wrote:
| Battery grid storage would be dead in the water, as we
| already use Superconducting Magnetic Energy Storage for
| grid stability and ultra-clean power in certain industries
| - except suddenly a huge chunk of issues involved in making
| large power SMES will disappear.
|
| They won't replace portable batteries soon, but room
| temperature superconducting will greatly increase
| efficiency in all areas of electricity, including higher
| power motors (the efficiency gains are good enough that
| superconducting motors and generators have been attempted
| despite needing supercooling). Also, a simple SMES could
| easily buffer future BEV truck charging station despite
| projected 1MW connection per charging truck.
| m463 wrote:
| I wonder if it would really mean a different sort of
| battery maybe like a super capacitor that doesn't
| discharge.
| [deleted]
| CyberDildonics wrote:
| _Nuclear fusion, quantum computing, insane batteries_
|
| Why do you think any of these are true?
| simmanian wrote:
| How would this make climate change easier to deal with?
| Because it would make everything that much more efficient?
| I'm honestly trying to understand the implications.
| swader999 wrote:
| Batteries and nuclear fusion. With easy energy, you can
| pull the carbon out of the air.
| BWStearns wrote:
| Long distance power transmission suffers losses from
| resistance. Superconductors don't suffer losses. With
| superconductors you could stick a giant wind farm in the
| ocean and cover the Sahara in solar panels. Run
| distribution lines from there to everywhere else and pretty
| much call it a day on the planet's power needs. (lots of
| things glossed over, not the least of which are social and
| geopolitical but you get the idea)
| nate_martin wrote:
| It takes energy to remove carbon from the atmosphere. With
| abundant energy from fusion you could just remove the
| carbon added by humans.
| hatsunearu wrote:
| The last line of the paper says this discovery will lead to a
| new age of humanity, and they aren't joking.
| willis936 wrote:
| Lead is used in many places. You should avoid checking what
| battery is in your ICE vehicle.
|
| What matters is how lead is handled. With hope, mankind will
| never lead a generation the way burning millions of gallons
| of leaded fuel did. Certainly no use of a lead superconductor
| could hope to accomplish that level of damage.
| kube-system wrote:
| This is a leading example of how homographs can lead us
| astray.
| hatsunearu wrote:
| I think you replied to the wrong parent?
| tamimio wrote:
| ??
| ChuckMcM wrote:
| Raise your hand if you contacted Aldritch about the two pre-
| cursor materials :-)
|
| This is an excellent summary and like Derek I have high hopes
| (but low expectations) that by the end of this week we'll see
| some tentative confirmation. This stuff isn't particularly hard
| (or expensive!) to make so that should really make for
| interesting news and some very fun products if it is proven out.
| hcks wrote:
| Don't waste your time, it'll be disproved 10 times before your
| reactants get delivered.
| kstrauser wrote:
| By whom, if no one orders the ingredients to run the tests?
| hatsunearu wrote:
| Presumably there are some labs with a very large spice
| cabinet.
| mitthrowaway2 wrote:
| Do handle these carefully, powdered lead oxide is no joke!
| techdragon wrote:
| Good luck with your samples and in the very least it should be
| good fun to play a small part in the replication of results. If
| documented well enough you might even wind up in a meta-study
| some day.
|
| The bigger the impact the more of a splash it will make in
| _social contexts_ consequently we see a lot of blatant and
| cautious naysayers with various explanations and individual
| explanations for the logic of their refutation.
|
| But it's If it's shocking enough, groundbreaking enough, anyone
| with the expertise to try will do so either to see if it's
| right instead of waiting around for someone else to do it and
| write it up and publish it, or to prove that it's not and for
| something this big at least, give BobbyBrocolli a new possible
| video topic to consider.
| seventytwo wrote:
| Fingers crossed!
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