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

Successful room temperature ambient-pressure magnetic levitation of LK-99

arxiv.org

Post reply on HN
Print view View original

911–920 of 1001 posts

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#911

Post by hackerlight »

anigbrowl wrote: post #781
softwaredoug wrote: post #705

I no nothing about superconductors. And have been largely ignoring this until it seemed more certain. Can someone ELI5 why this matters? What does it enable technologically? Flying cars? Fusion reactors? Magic fix for global warming?

Conventional conductors have resistance, so when you run electrical current through them they heat up; this is why laptops and desktops have fans to cool the chips, why phones get hot and so on. Superconductors transmit energy without resistance, so the heating problem goes away and the energy costs of running the device go way, way down. Basically you can pump more through smaller wires without worrying about them m…

> energy costs of running the device go way, way down

By how much?

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#912

Post by danielheath »

happytiger wrote: post #901
Al-Khwarizmi wrote: post #798

Earlier quoted context omitted.

This is a quite biased view. As a non-Chinese scientist, I can attest that there is intense pressure to publish as many papers as possible pretty much everywhere , and this leads to a problem of bad research across the world. China may be among the worst offenders in this respect, but the particular thing the OP is asking about doesn't strike me as a Chinese-specific thing at all. I see non-Chinese scientists rushing…

China publishes more science research with fabricated peer-review than everyone else put together https://qz.com/978037/china-publishes-more-science-research-... I respectfully submit that you may be providing an anecdotal experience. It’s so bad that China’s courts have called for the death penalty for scientific fraud. https://www.statnews.com/2017/06/23/china-death-penalty-rese... Goodness me.

“More than everyone else together” is meaningless without considering the relevant population sizes (in this case, the relevant population is “number of researchers producing papers”).

If China has half the worlds academics-writing-papers, one would _expect_ them to be responsible for half the fabricated ones.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#913

Post by hackerlight »

erlich wrote: post #702
anonylizard wrote: post #666

Earlier quoted context omitted.

NYT actually is the only newspaper outside of Korea to get into contact with the authors, and received an exclusive video from the professor. Go to their science section. Now it isn't top news, but when it is confirmed, it'll be front page news on every western newspaper.

This furthers my point. They even got an exclusive and still run Trump stuff.

Yeah sure, but you're singling out them as if it's not the case with every mainstream media outlet. We already know that this type of story isn't what drives revenue and that's why it's not on the front page.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#914

Post by chiph »

mk_stjames wrote: post #735

This is obviously a quickly produced paper to get the finding out but.... I find there to be so much missing and so many things poorly worded or posed about their process that would have taken zero time to expound upon, it's infuriating. "All the reactions are carried out under 10^-2 Pa" OK, I know they mean 10^-2 of vacuum. But why not say that? "10^-2 Pa" isn't enough. Was this a full vacuum oven? Done in sealed qu…

Or they are holding the details of their process close to their chest, in anticipation of a lucrative spin-off.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#915

Post by salty_biscuits »

dotancohen wrote: post #907
Sharlin wrote: post #876

Earlier quoted context omitted.

Magnetic force scales as 1/r^3, not 1/r^2 like gravity. That's why your standard issue fridge magnet measurably attracts stuff only from a very close distance, but when it does, it easily counters the gravitational attraction of the entire planet¹. This 1/r^3 relationship can be derived easily enough by integrating, but essentially it's because magnets are dipoles and the farther away you are, the smaller the apparen…

> Magnetic force scales as 1/r^3, not 1/r^2 like gravity The magnetic force and gravity are two of the four fundamental forces, no? The others being the strong and weak nuclear force? At what rate do those two scale at?

If you are really close to one pole of a magnet and far away from the other then the force scales like 1/r^2, it is in the far field under the influence of both poles of the magnet that it scales like 1/r^3. Electrostatics scales like 1/r^2 (because you fet isolated charges). The other two are a complicated story.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#916

Post by salty_biscuits »

dmix wrote: post #771
mk_stjames wrote: post #735

This is obviously a quickly produced paper to get the finding out but.... I find there to be so much missing and so many things poorly worded or posed about their process that would have taken zero time to expound upon, it's infuriating. "All the reactions are carried out under 10^-2 Pa" OK, I know they mean 10^-2 of vacuum. But why not say that? "10^-2 Pa" isn't enough. Was this a full vacuum oven? Done in sealed qu…

What personal benefit does this gain someone to publish it so quickly? Is it just social media attention?

It's just a preprint. I appreciate the fast update of progress on a new development. Just don't give it the same weight as a peer reviewed piece.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#917

Post by lottin »

smolder wrote: post #863
lottin wrote: post #313

Earlier quoted context omitted.

> 6. World recognition to manage resources globally Do you mean communism?

Communism is one model of government among many. Do YOU think that intelligent management of global resources requires communism? Is the United nations a commune because the member countries cooperate in some way? Isn't there an area between "independent actors acting selfishly" and "communism"? I don't think they were implying communism. Which is good, because IME people on this forum can't have honest discussion or…

> Do YOU think that intelligent management of global resources requires communism?

I think a CENTRALISED management of the world's natural resources would require communism.

Decentralised management is what we have now.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#918

Post by hanniabu »

chiph wrote: post #914
mk_stjames wrote: post #735

This is obviously a quickly produced paper to get the finding out but.... I find there to be so much missing and so many things poorly worded or posed about their process that would have taken zero time to expound upon, it's infuriating. "All the reactions are carried out under 10^-2 Pa" OK, I know they mean 10^-2 of vacuum. But why not say that? "10^-2 Pa" isn't enough. Was this a full vacuum oven? Done in sealed qu…

Or they are holding the details of their process close to their chest, in anticipation of a lucrative spin-off.

A breakthrough of this kind should be illegal to patent

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#919

Post by lifthrasiir »

bunniez wrote: post #859
lifthrasiir wrote: post #384

So what the heck has happened with LK-99 really? (Disclaimer: I'm no physicist nor chemist, but I have co-written a report on three LK-99 papers [1] and am tracking the Twitter discussion as much as I can. I also got some help from knowledgable friends---much thanks for proof-reading.) It turned out that LK folks were not talking about some stupid shit. Specifically they were one of the last believers of long-forgott…

It's Chwe/Choi, not Chair.

"Chair" is a preferred transliteration for this particular person. It is a very uncommon ("Choi" is the single preferred name), but still plausible one.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#920

Post by lifthrasiir »

lifthrasiir wrote: post #384

So what the heck has happened with LK-99 really? (Disclaimer: I'm no physicist nor chemist, but I have co-written a report on three LK-99 papers [1] and am tracking the Twitter discussion as much as I can. I also got some help from knowledgable friends---much thanks for proof-reading.) It turned out that LK folks were not talking about some stupid shit. Specifically they were one of the last believers of long-forgott…

This post has now accumulated some substantial updates, which should not change the conclusion but fix possible misreadings and inaccuracies. Please refer to the HackMD post for the latest version.
Post reply on HN