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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

#391

Post by Dylan16807 »

nindalf wrote: post #381
Dylan16807 wrote: post #372

Earlier quoted context omitted.

That's just a list of good inventions. GPS, disposable razor, many of these are not impactful enough to be "black swan but good". And things like clocks and batteries were slowly refined over many, many years, so they don't fit either.

Respectfully, you don’t know what you’re talking about if you think GPS “isn’t impactful enough”. Don’t fall into the trap of reacting with “meh” to everything. Maybe you just don’t know? Maybe you don’t realise how much modern life depends on say, the Haeber-Bosch process or the shipping container? “Oh it’s just a metal box”, a person who doesn’t understand it might say.

> Respectfully, you don’t know what you’re talking about if you think GPS “isn’t impactful enough”.

How informative of you.

GPS does things better but we can do generally the same things without it.

Don't think about what would happen if we ripped out all GPS functionality overnight, think about what would happen if we had a decade to implement replacements.

The loss of accuracy wouldn't be that important.

> the Haeber-Bosch proces

That one's pretty great, it's probably worth including.

> or the shipping container? “Oh it’s just a metal box”, a person who doesn’t understand it might say.

Hmm, focus on cargo ships and you can see a pretty rapid revolution, but in a wider lens maybe it was more of a broad evolution. I'm not sure.

But my point was that the list was too long, not that it didn't have any valid examples.

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

#392

Post by hinkley »

scarmig wrote: post #48
bilsbie wrote: post #39

Earlier quoted context omitted.

What temperature?

326K (+127 deg F) and 340K (+152 deg F) for their less and more pure samples respectively. And, yes, if it's a superconductor as we understand them, that's the temperature at which it would have zero resistance as well.

So that’s within the range of off the shelf cooling equipment to maintain superconductivity.

Any speculation if that’s consumer, commercial, or industrial off-the-shelf?

Sounds like we may be talking running an MRI off of a mini split system.

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

#393

Post by andbberger »

rvcdbn wrote: post #333
ChuckMcM wrote: post #129

For those experiencing this type of "black swan, but good" event for the first time, it is helpful to recognize that the human tendency to believe that all future "big events" will be dystopian downers, is statistically unsound. For a while I've kept a list of the things that could be "good" swan events, but to be fair I didn't have "room temperature superconductor on that list" :-) Other things that could happen: 1)…

There is an anthropic line of reasoning over Everettian branch universes where you can actually expect these types of highly unlikely events to happen more often than chance alone would predict if they promote futures with more Born-rule weighted observer-moments.

nonsense.

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

#394

Post by arketyp »

nindalf wrote: post #381
Dylan16807 wrote: post #372

Earlier quoted context omitted.

That's just a list of good inventions. GPS, disposable razor, many of these are not impactful enough to be "black swan but good". And things like clocks and batteries were slowly refined over many, many years, so they don't fit either.

Respectfully, you don’t know what you’re talking about if you think GPS “isn’t impactful enough”. Don’t fall into the trap of reacting with “meh” to everything. Maybe you just don’t know? Maybe you don’t realise how much modern life depends on say, the Haeber-Bosch process or the shipping container? “Oh it’s just a metal box”, a person who doesn’t understand it might say.

Is it a black swan though? I can imagine something like GPS was envisioned well before the first satellites were even launched into orbit. Note, I'm not disputing you. This got me thinking about the nature of invention and discovery.

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

#395

Post by XorNot »

ETH_start wrote: post #334
ChuckMcM wrote: post #129

For those experiencing this type of "black swan, but good" event for the first time, it is helpful to recognize that the human tendency to believe that all future "big events" will be dystopian downers, is statistically unsound. For a while I've kept a list of the things that could be "good" swan events, but to be fair I didn't have "room temperature superconductor on that list" :-) Other things that could happen: 1)…

Excellent insight and perspective. > 2) Commercially viable fusion energy. Will change a lot of things. How would that be any better than commercially viable fission breeder reactors (which seem far closer to reality than commercially viable fusion energy)?

Mostly public perception (annoyingly): people are still going to have a go at being anti-nuclear about it, but building a fusion power reactor is going to have a lot more public cultural cachet to draw upon then fission. We've got a generation of science fiction who's core message is "fusion power solved all the problems".

Though there are genuine advantages: for as radioactive as the interior of a fusion reactor may get, if you cut power it'll just sit there safely doing nothing. No decay heat, no potential isotopes to leak - maybe a puff of tritium gas - but that's it. It is a technology that has a perfect control loop for safety because it can't self-sustain at all.

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

#397

Post by s1artibartfast »

amrocha wrote: post #338
s1artibartfast wrote: post #330

Earlier quoted context omitted.

It would be the opposite. Nobody with develop technology to utilize it because there are no protections. No MRI, No Fusion, ect.

Bullshit, science isn't driven by patents or funded by private industry.

doing just about anything with science is.

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

#398

Post by shrx »

ben_w wrote: post #374
Smoosh wrote: post #280

Earlier quoted context omitted.

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".

Eternal youth != immortality; given accidental and deliberate injuries and deaths, the "half life" (feels wrong in this context) is about 1000 years. As for dictators: it's not like guillotines stop working. What will keep dictators (if eternally young, or their offspring if not) in power forever is competent and obedient AI manning the police and army.

Source on the half life number?

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

#400

Post by urinotherapist »

ben_w wrote: post #368
urinotherapist wrote: post #337

Earlier quoted context omitted.

Commercially viable fusion can be achieved with commercially viable source of muons: https://en.wikipedia.org/wiki/Muon-catalyzed_fusion https://link.springer.com/article/10.1007/s00016-009-0006-9 https://www.annualreviews.org/doi/pdf/10.1146/annurev.ns.39.... http://large.stanford.edu/courses/2016/ph241/yoon1/ https://www.chemeurope.com/en/encyclopedia/Muon-catalyzed_fu...

Slightly harder than I remembered: > Even if muons were absolutely stable, each muon could catalyze, on average, only about 100 d-t fusions before sticking to an alpha particle, which is only about one-fifth the number of muon catalyzed d–t fusions needed for break-even, where as much thermal energy is generated as electrical energy is consumed to produce the muons in the first place, according to Jackson's rough est…

> More recent measurements seem to point to more encouraging values for the α-sticking probability, finding the α-sticking probability to be about 0.5% (or perhaps even about 0.4% or 0.3%), which could mean as many as about 200 (or perhaps even about 250 or about 333) muon-catalyzed d-t fusions per muon.[29][30] Indeed, the team led by Steven E. Jones achieved 150 d-t fusions per muon (average) at the Los Alamos Meson Physics Facility.[31] Unfortunately, 200 (or 250 or even 333) muon-catalyzed d-t fusions per muon are still not quite enough even to reach "break-even," where as much thermal energy is generated (or output) as the electrical energy that was used up (or input) to make the muon in the first place. This means, of course, that not nearly enough thermal energy is generated thereby to be able to convert the thermal energy released into more useful electrical energy, and to have any electrical energy left over to sell to the commercial electrical power "grid." The conversion efficiency from thermal energy to electrical energy is only about 40% or so. Also, some not inconsiderable fraction of that electrical energy (hopefully not all of it) would have to be "recycled" (used up in deuteron particle accelerators, for example) to make more muons to keep the muon-catalyzed d-t nuclear fusion fires burning night and day.[32] The best recent estimated guess of the electrical "energy cost" per muon is about 6 GeV (billion electron Volts), using deuterons that are accelerated to have kinetic energies of about 800 MeV per nucleon, with accelerators that are (coincidentally) about 40% efficient at taking electrical energy from the Alternating Current (AC) mains (the plugs in the wall) and accelerating the deuterons using this electrical energy.

Yep, it's challenging. Maybe this rate can be improved by applying alternating voltage to reactor. Muons are charged particles, so they can be accelerated further. (Just idea)

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