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A room-temperature superconductor? New developments

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Re: A room-temperature superconductor? New developments

#491

Post by foven »

badman2001 wrote: post #171

the dft results are definitely interesting, but i note that with the caveat that my background is in experimental condensed matter physics for materials like this and not theoretical, my understanding is that the dominant feature of the conclusions (the flat bands) is a necessary but not sufficient condition for superconductivity in the way the authors describe. again, in experimental condensed matter physics it's ac…

Something that I find hard to understand is why there is superconductivity without cooper pairs; granted my understanding is related to more traditional superconductors and I'm not really very knowledgeable about the cutting edge high-Tc stuff.

Re: A room-temperature superconductor? New developments

#492

Post by ThisIsMyAltFace »

_yb2s wrote: post #384
dirtyid wrote: post #329

Earlier quoted context omitted.

Varies by field but last few years PRC been reaching parity to topping various science and innovation indexes, PRC institutions also breaking global top100 and general trend of moving up rankings. TLDR is PRC science exploded after mid 2010s - lag effect from academic reform in 00s. Biotech/bioeconomy a outlier though - just got elevated to strategic sector with 500b usd investment in last year's 5 year plan, so expe…

I’ll take what you are saying at face value, but point out that academic career pipelines are slow- it’s often about 15 years to go from college freshman to starting out as a “young” PI in the USA. If what you are saying is true, it will still be another 5+ years before we start seeing top students that stayed in China publishing as PIs. Edit: Which lines up with what you said at the top of your post.

> I’ll take what you are saying at face value

Given this poster's history, I would not do that

Re: A room-temperature superconductor? New developments

#493

Post by klysm »

baq wrote: post #444
klysm wrote: post #422

Earlier quoted context omitted.

> Batteries that don't take any time to recharge Huh? Is this actually a thing that this enables? I don't initially see how

It’s a zero resistance wire. Build a loop and pump electrons in. Need them back? Connect an off-ramp. There are limits how much you can pump into it, it isn’t magic… but it almost is actually. https://en.m.wikipedia.org/wiki/Superconducting_magnetic_ene...

But the current density limit makes that not super effective right?

Re: A room-temperature superconductor? New developments

#494

Post by bagels »

nemof wrote: post #46
delfinom wrote: post #22

Earlier quoted context omitted.

Can't tell if it's a troll by having a video clip of a video clip

here's the original video, i assume the twitter user didn't know how to download or deeplink to it so they screen recorded it. https://vdn3.vzuu.com/HD/7d42236a-3065-11ee-a787-7e9db7aa394...

Access denied

Re: A room-temperature superconductor? New developments

#495

Post by boppo1 »

LASR wrote: post #203
hanniabu wrote: post #126

Earlier quoted context omitted.

Would a room-temp superconductor make it feasible to cover desert regions with solar panels and transport the electricity long distances?

Yes it makes it more feasible. But even with superconductors, you still need to build out the long-distance grids. With ceramics, manufacturing that much powerline might be the challenge. With the maximum current density reported for this material, you might need a huge x-sectional area. You still have to worry about batteries. Unless if you place equal numbers of panels separated by 120° meridians for example. And t…

>You still have to worry about batteries.

I keep hearing mixed things about superconductors being useful for energy storage.

Re: A room-temperature superconductor? New developments

#496

Post by fsh »

derefr wrote: post #451
postmodest wrote: post #442

Earlier quoted context omitted.

Wouldn't the battery itself still have resistance? Or is the superconducting material itself a battery?

Depends. A single battery cell would have nontrivial resistance, yes. But a big bank of batteries, like are in an EV? Very hard to give them enough current to heat them up. Most of the "heat problem" is from the bottlenecked current path into the car; once you fan out across all the individual cells, each individual cell isn't receiving much current. And a bank of supercapacitors? You could charge it effectively inst…

The current is limited by what the battery chemistry can take, not by the cables. This is why the first 80% can be charged quite fast in modern EVs, and the last 20% are really slow.

Re: A room-temperature superconductor? New developments

#497

Post by jerf »

zepearl wrote: post #487
jtchang wrote: post #418

The ramifications of the inflection point we are currently at is mind boggling. I had a hard time explaining this last night but we may very well be witnessing the beginnings of a technological transformation era much like when the p-n junction was invented. From the 1940s standpoint it would be hard to envision all we had today. - Lossless transport of energy - Batteries that don't take any time to recharge - Faster…

> Can I have my flying car now? Let's not forget the flying skateboard of the film "Back to the future". I loved it in the film and it's a dream that I still have today - I'm now almost 50 years old so I would probably crash and get killed by using it, but I would still give it a try :)

Unfortunately, while you can indeed build hoverboards with superconductors and they do work, you still need a magnetic surface for it to ride over. I don't believe generalized hoverboards that will work on all surfaces like BttF are possible.

Re: A room-temperature superconductor? New developments

#498

Post by marshray »

rvnx wrote: post #308
marshray wrote: post #288

Earlier quoted context omitted.

Over a handheld neodymium magnet. None of the videos have yet shown complete 'levitation', they all have a corner on the surface. But still, not behavior that anyone has ever seen from lead before.

But couldn't it just be a magnet ? I don't understand how it's a proof. You can already do what is in the video (and even better), with for example, pyrolitic carbon ? https://en.wikipedia.org/wiki/Pyrolytic_carbon

Lead weighs a lot more than pyrolytic carbon.

Re: A room-temperature superconductor? New developments

#499

Post by PBnFlash »

thorncorona wrote: post #469
Melatonic wrote: post #462

Earlier quoted context omitted.

That is.....kind of a huge limitation of the technology lol. Still very cool but less hype

I believe the implication is that LK-99 is basically a demonstration of an entire class of materials which should have room-temp superconduction properties. IE we can enumerate through the entire class and find the ones with the properties we want.

There is no reason to assume that even if it's real.

In fact, the tight tolerances of this seem to indicate the opposite.

Re: A room-temperature superconductor? New developments

#500

Post by nicechianti »

jtchang wrote: post #418

The ramifications of the inflection point we are currently at is mind boggling. I had a hard time explaining this last night but we may very well be witnessing the beginnings of a technological transformation era much like when the p-n junction was invented. From the 1940s standpoint it would be hard to envision all we had today. - Lossless transport of energy - Batteries that don't take any time to recharge - Faster…

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