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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

#601

Post by httpz »

mrtksn wrote: post #470
pjungwir wrote: post #207

The last week reminds me of the story of Bardeen & Brattain's invention of the transistor (e.g. in The Idea Factory ). It barely worked and heaven forbid you bump the table. There was even a third slighted figure who wanted credit. Part of me wants to be skeptical but OTOH if it's hard to reproduce that seems totally normal. How exciting that some other people have got it working now.

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.

Apparently the theory behind LK-99 was inspired by the studies from Eastern European scientists. However, after the Soviet collapse, the study was lost.

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

#602

Post by DoctorOetker »

DoctorOetker wrote: post #580

On the following suppositions: 1: Superconductivity becomes widely confirmed 2: Reproducibility remains microscopic Imagine a game of rolling a collection of n dice (normal 6 sided), where the player wins if all N dice are 4 or higher (probability 1/2 for a single dice). Then the probability of a lucky roll is P = (½)ⁿ So the smaller the collection of dice the more likely a lucky roll becomes. Consider a hypothetical…

Consider the work of C. V. Boys.

https://en.wikipedia.org/wiki/C._V._Boys

Especially: "On the Production, Properties, and some suggested Uses of the Finest Threads." 1887

https://zenodo.org/record/1431517/files/article.pdf

This is a very entertaining read, and highly recommended.

He produced extremely fine threads of glass, quartz, etc. finer than the visible light diffraction limit. (Which he would use to construct sensitive torsion balances)

He was inspired by Peles Hair. (Volcanoes grow hair too...). He first describes electro-spinning and its limitations (uncontrolled growth of hair which mattes together).

How did he do it? He used a miniature crossbow, modified so he could trigger it by foot pedal, leaving his hands free to work.

He would first produce a small thin section by more conventional means, glue one end to a fine dart or arrow (a piece of straw really).

In the next sentence "blowpipe" is not a launching device, but a device to heat a small sample to a high temperature.

Then he would use a blowpipe and melt the piece of say quartz until a bead forms, at which point he would trigger the cross bow.

As the arrow of straw shot away it draws the bead of melt to a long fine thread.

Perhaps this can be modernized to vacuum or inert atmosphere, melt the quasi LK-99 sample until it beads, then shoot away. Rewind the resulting thread and re-anneal any non-superconductive segments.

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

#603

Post by baq »

p-e-w wrote: post #592
dwighttk wrote: post #589

If you believe it there’s money to be made https://polymarket.com/event/is-the-room-temp-superconductor...

This is the only website I actually trust to give me an accurate picture of where we stand on LK-99. As long as the blue line doesn't cross the red one, I won't believe in it. Money talks, bullshit walks.

it's a 100% sentiment driven market. wouldn't put too much weight on it.

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

#604

Post by ant6n »

cthalupa wrote: post #199
HeartStrings wrote: post #166

Earlier quoted context omitted.

Is this actually true?

Yes and no. There's no possible way to have a superconductor be an actual hoverboard out in the broader world - the magnetic field of the earth is just nowhere near strong enough. You can make specialized areas where it would work, though. It's even been done already with LN2 cooled superconductors - https://www.theverge.com/2015/8/4/9091951/lexus-hoverboard-v... SC could help enable nearly lossless transmission over…

The superconducting transmission line doesn’t need big towers, a clear path, a direct path or a shortest path.

It’ll be more like a thick pipe, perhaps buried.

Much easier it get a right of way, less environmental impact, less paperwork, less time to build.

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

#605

Post by jacquesm »

XorNot wrote: post #408
hwillis wrote: post #383

Earlier quoted context omitted.

You can't get CT scans very often, because they hit you with large doses of ionizing radiation. Ultrasounds are low-resolution spotlights; you shine them at a particular spot to diagnose something specific. With this you could get an MRI at your annual checkup. You could diagnose all number of diseases like that, not to mention 95% of cancers. Each year your scan is automatically compared to the previous year, and an…

> We might eventually transition away from AC power entirely. This is actually a really good point I hadn't fully considered, but it's right: the primary reason we use high voltage anywhere is because it minimizes resistive losses (and the reason we use AC is because it's easy to transform between voltages). But most of the stuff in my home doesn't need high voltage - it's all running at 5V or 12V. Or it's a motor wh…

It's interesting to see how many assumptions about our world are underpinned by the lack of superconducting material. That also immediately gives you an idea of how transformative (heh.) room temperature superconductors would be.

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

#606

Post by dwighttk »

p-e-w wrote: post #592
dwighttk wrote: post #589

If you believe it there’s money to be made https://polymarket.com/event/is-the-room-temp-superconductor...

This is the only website I actually trust to give me an accurate picture of where we stand on LK-99. As long as the blue line doesn't cross the red one, I won't believe in it. Money talks, bullshit walks.

What happened on July 31 to make the market briefly flip?

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

#607

Post by djoldman »

Any process chemists here care to comment on this synthesis? I'm craving more information from these papers on the synthesis: weights, sources, purities, and powder sizing of precursors, models of ovens, glass details, etc. etc.

When there's clearly big and important differences between everyone's outputs using the "method similar to that reported by Sukbae Lee et al." then it's important to know every detail!

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

#610

Post by drtgh »

appplication wrote: post #205
Keyframe wrote: post #167

Earlier quoted context omitted.

Almost instant battery charging for example.

Do you mean replacement of chemical batteries for superconducting ones?

if he means that, I do not see it happening so easily,

Energy storage in a superconductor is done in the form of magnetic field, a superconducting induction coil (SMES), whose density of energy storage per kilogram is highly inferior to a capacitor and a supercapacitor, which stores energy in the form electric fields, and whose density of energy storage per Kg in turn is very inferior to chemical batteries.

The magnetic fields are charged and released quicker in inductors than in capacitors (and than in chemical batteries), also the material have a longer life, and the rate of self-discharge is sightly inferior in superconducting inductors, nevertheless the density per kilogram -and to administrate such sudden energy release- limits very much the applications.

If LK99 becomes true, and is improved much (as the electrical current in the paper is limited to milliamperes range), at middle term I don't think on it happening.

If at future is achieved superconducting through nanowires, with inferior weight to batteries, may be, but in a car for example would need the added weight of metallic "magnetic shields" for health security.

IMHO, I don't see it beyond stationary applications.

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