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

arxiv.org

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

#871

Post by ta1243 »

concordDance wrote: post #406
scarmig wrote: post #15

Earlier quoted context omitted.

The paper shows a clear phase transition to diamagnetism as the material is cooled. That would be seen in superconductors and not in regular diamagnetic materials. I'm not aware of any that have that kind of phase transition. Though since we're in weird territory here, it's important to note some weird non-superconductor behavior that's beyond regular diamagnetism might be going on as an alternative explanation. But…

> this pushes my odds above 50% for the first time. Time for you to make some money then? :D https://polymarket.com/event/is-the-room-temp-superconductor...

The sensible thing would be to bet against it - as shown by xkcd

Did that site predate https://xkcd.com/955/ or was it inspired by it?

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

#872

Post by [deleted] »

Cosi1125 wrote: post #737
nwiswell wrote: post #345

Earlier quoted context omitted.

As I read this list, the rhythm to We Didn't Start the Fire spontaneously started playing in my head. Sorry not sorry if I just subjected you to the same.

Auctions, GPS, Postage stamp, video games, Public key cryptography, Shipping containers. iPhone, pencil, Clocks and contraceptive pill, Passports, batteries, Banking, antibiotics. Double entry book-keeping, Canned food, air conditioning, Razors, solar cells, Sanitary towels. Retirement, printing press And the Haeber-Bosch process Infant formula, Exchangeable parts. Light bulb, concrete, Sewing machine, spreadsheet, S…

[deleted]

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

#873

Post by bglazer »

kevstev wrote: post #760
mrtksn wrote: post #470

Earlier quoted context omitted.

Things also tend to be invented at about the same time at different places. I wonder if there are other people who were this close to invent it but just couldn't get it right.

Last year I read The Double Helix and The Code Breaker within a few months of each other, and what really stood out to me is that while we celebrate the first person who discovers something, in reality there were several teams all racing to the finish line, and were sometimes days or only even hours behind in presenting their findings. Yet only one team gets the accolades and their names in textbooks, the others are…

Another example that might be of interest is the use of neural networks in Monte Carlo Tree Search. In 2017 there were two papers published showing how effective the combination of NN’s and MCTS are for planning in board games.

One is an algorithm called ExIT published by Anthony et al, it showed excellent performance on a somewhat obscure board game called Hex. The authors using a typical academic lab setup to achieve this. It has a very impressive 300ish citations.

The other paper is AlphaGo, which has about 10k citations and a Netflix documentary. There are some algorithmic differences that probably make AlphaGo strictly better than ExIT but the big difference seems to mostly be that one group had like a thousand GPUs for a month.

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

#874

Post by skeaker »

Smoosh wrote: post #280
holtkam2 wrote: post #274

Earlier quoted context omitted.

1. Cure for aging 2. AGI exists and ends up being somehow, unexpectedly easy to control 3. Russia / China / North Korea eventually become democratic Some of the “good” black swans at the top of my mind…

I'm unsure if we want people living forever. While disease, illness, and senility are terrible things, as soon as people can live forever we will have eternal dictatorships (or people trying for it) as well as other questions of perpetual inequality. "Death renders all equal".

I have never liked this mentality in discussions around immortality that essentially boil down to "I would die if it meant people I don't like can die too." "A bad actor living for a long time would make our quality of life lower" is usually the given reasoning, but do you know what quality-of-life rock bottom is? It's being dead! Once you are dead there is absolutely no good to ever happen to you ever again! And the counter for this is then usually "well what if I like being dead," which is great for you, but I and many many others happen to very much dislike the idea, and your stance would drag us down with you.

That's all without even mentioning other benefits like cumulative knowledge of multiple lifespans being contained in one person allowing for new scientific breakthroughs.

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

#875

Post by bsmith89 »

mitthrowaway2 wrote: post #814
kevstev wrote: post #760

Earlier quoted context omitted.

Last year I read The Double Helix and The Code Breaker within a few months of each other, and what really stood out to me is that while we celebrate the first person who discovers something, in reality there were several teams all racing to the finish line, and were sometimes days or only even hours behind in presenting their findings. Yet only one team gets the accolades and their names in textbooks, the others are…

Two independent research groups, one from Japan and one from the US, simultaneously published their discovery of the NdFeB magnet in the same issue of the same journal.

I don't know this particular story, but — FWIW — it's common for different teams working in the same field to be aware of each other's manuscripts and impending submissions. When two teams are about to submit papers with the same discovery, they'll often work with an editor to put it in the same journal issue.

By coordinating a simultaneous publication they can get extra publicity for the discovery, both get the first-mover advantage in citations (both papers get cited by everyone), and also get breathing room to be fully rigorous and write the best possible paper.

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

#876

Post by Sharlin »

pmontra wrote: post #870
Roritharr wrote: post #593

The Varda Team just posted a really high-resolution video of the diamagnetism: https://twitter.com/andrewmccalip/status/1687405505604734978

Noob question: if whatever is happening is strong enough to raise one of the ends of the sample, why doesn't raise both? After all gravitation is many order of magnitudes weaker than electromagnetism. Did they calibrate the setup to closely match the gravitational force on the sample? Why not push a little more and make it fly up the the cap of the container?

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 apparent distance between the poles and the "more neutral" the magnet looks like.

Anyway, that's why there's an equilibrium distance where the forces balance. But superconductors also exhibit a very strange phenomenon called flux pinning [1] where a levitating object is held in place by magnetic field lines and you can even turn the whole thing upside down and it still levitates even though the forces don't cancel each other out anymore!

[1] https://en.wikipedia.org/wiki/Flux_pinning

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¹ To be fair, "the entire planet" is also around 6000 km away, calculation-wise, but still!

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

#877

Post by sheepscreek »

light_hue_1 wrote: post #807
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…

It's not biased, it's a fact. I see it all the time as PC/AC/reviwer/etc. There is deluge of terrible papers from China that are just a mess, below any imaginable standard. Ones that labs in the EU/US/Russia/Japan/etc. don't put out. Yes, everyone has to publish, and there are bad papers out there, but the volume and low quality from China is unmatched.

> It's not biased, it's a fact. I see it all the time as PC/AC/reviwer/etc.

Let's agree this is anecdotal at best, and move on. Facts need data to back them up. There's no data or links to research in this post.

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

#878

Post by mrguyorama »

simias wrote: post #763
someplaceguy wrote: post #141

Earlier quoted context omitted.

It would have been more convincing if you had given real past examples rather than speculative future ones :) Although I'm pretty sure there are plenty that many people can think of, so it doesn't really detract much from your point.

It's perhaps not as life-changing as some of the sibling replies but one thing that has really amazed me over the past few decades is how much lighting has progressed. When I was a kid in the 90's I already enjoyed electricity and electronics and I would play with those low power incandescent lightbulbs powered by 9V batteries. They would generate a lot of heat and very little light, to the point that it wasn't easy…

I like to point this out in relation to Star Trek. In TNG, they had tablet computers, replicators, teleportation, voice command, all these things that we consider future magic or current awesome technology. And then an away team goes down to the surface and pulls out a flashlight using an incandescent bulb that can barely be seen.

LEDs are genuinely revolutionary in a way everyone just kind of overlooks.

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

#879

Post by jamiek88 »

regularfry wrote: post #762
jacquesm wrote: post #688

Earlier quoted context omitted.

There would be some massive deprecation at the CERN and ITER sites.

You've got me wondering how much cheaper ITER actually gets if you don't need the magnets to be cryogenic.

What about colliders too?

Imagine large hadron collider without cooling!

We could have the unimaginably huge hadron collider!

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

#880

Post by samstave »

samstave wrote: post #335

This is ELI5 stupid Q: What may be the benefit of running a sequence of "coils" or whatever the Loops may be comprised of such that the N/S to whatever polarity positions are required, could be an LK-99 then a super cooled, then an LK-99 etc... If it was in a toroidal spiral (everyone things of the trajectories as linear, but toroidals spirals are most efficient) you could have hybrid tracks - where maybe a linear la…

What is we made coroidal spirals over a ferrit but in alternating polatities

but we can control.

I a m talking out my butt - thus a toiroidal wrapp where by the torioidal spin in induced trough a mecury spinning magnetic slurry... as basically a spinned slurry ......

But that just me...

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