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A room-temperature superconductor? New developments

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Re: A room-temperature superconductor? New developments

#641

Post by Palpatineli »

mrtksn wrote: post #37
RandallBrown wrote: post #15

Earlier quoted context omitted.

Can someone explain how this video shows superconductivity?

[not an expert but...]It shows strong diamagnetism(being repelled by both of the poles of a magnet), which is a property of superconductors. Not necessarily a superconductor though, that’s still to be established but at least it shows that the inventors are up to something and it’s not complete fabrication.

That’s a stretch. Dias’ material has real color change under high pressure which is an expected property of superconductors but nobody would argue his paper was not complete fabrication

Re: A room-temperature superconductor? New developments

#642

Post by jojobas »

fsh wrote: post #516
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…

None of the things you listed are limited by the conductors in them. The efficiency of high voltage AC power lines is limited by capacitive coupling to ground. Battery charging is limited by the cell chemistry. CPU heat output is limited by the resistance of the semiconductors. Turns out metals (in particular copper) are already incredibly good conductors.

>The efficiency of high voltage AC power lines is limited by capacitive coupling to ground.

As often in engineering, the sweet spot is where multiple factors have ~equal contributions, so even a 50% win in one of the factors can't give you that much benefit.

For high voltage AC power lines it's Ohmic losses, corona discharge losses, and inductive losses.

Re: A room-temperature superconductor? New developments

#644

Post by sheepscreek »

fsh wrote: post #516
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…

None of the things you listed are limited by the conductors in them. The efficiency of high voltage AC power lines is limited by capacitive coupling to ground. Battery charging is limited by the cell chemistry. CPU heat output is limited by the resistance of the semiconductors. Turns out metals (in particular copper) are already incredibly good conductors.

But it is. A significant part of electronics engineering is dedicated to heat dissipation.

So what do we stand to gain?

At least a slight improvement in efficiency of transmission. And a huge improvement due to simpler heat dissipation needs.

So this might mean way faster battery charging - like 500 miles worth of charge in 5 mins. We’re mainly limited by how hot the batteries get during charging.

Re: A room-temperature superconductor? New developments

#645

Post by postmodest »

jiggawatts wrote: post #430
worldsayshi wrote: post #355

Earlier quoted context omitted.

Time to start mining asteroids.

Is this how the science fiction future we’ve all read in books becomes reality? SpaceX becomes an evil megacorp mining gold from the asteroid belt with LLM AI controlled robot slaves so that we can make hover cars using superconductors?

No no, you use the LLM AI to funnel real people into becoming Belters, then fake their communications back home with those same LLMs, then move your X HQ to Mars and oppress them from there.

...also, Elon would totally pull a Duarte....

Re: A room-temperature superconductor? New developments

#646

Post by bipop5000 »

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…

Hoverboards. I want those damn things as was prophesied by back to the future.

Re: A room-temperature superconductor? New developments

#647

Post by robot_no_421 »

whimsicalism wrote: post #523
scrlk wrote: post #392

Earlier quoted context omitted.

> I highly doubt they can preserve their pace of growth for next few decades without significant changes to the regime and liberalization. "Demographics is destiny" also comes to mind. Note how the era of "Japan Inc." during the 1980s was also the time when the post-war baby boom population were in their 30s-40s (i.e. peak productive worker population). As this cohort has aged and are now in retirement, Japan's econo…

The difference with the Japan case is that China is going to have a larger base of young, very well educated people than the US for at least the next century unless something changes dramatically with either birth rates or immigration.

China is facing severe demographic issues for the next 20-30 years due to their terribly short sighted one-child policy and their poor immigration rates. Literally the opposite of what you're saying. Where on earth did you get your facts from?

Re: A room-temperature superconductor? New developments

#648

Post by tnecniv »

I posted this elsewhere but I think it was after comments got merged in here, so sorry for the spam if you happen to see it twice:

I’m interested to know if anyone has any recommended resources on DFT or DDFT (the simulation method used here) for someone with good applied math knowledge but who is not a physicist. I have a decent working knowledge of stat mech from knowing about dynamical systems and information theory, but I am not a physicist. I’ve come across (classical) DFT before, but the tutorial papers I’ve come across get weighed down by a lot of physics jargon and notation that I don’t understand and they describe it in terms of certain physical systems that obfuscate whether I can adapt the method to problems I am interested (I think the answer is yes in my case but if I was confident I wouldn’t be asking). I could just rederive (classical) D or DDFT for my stochastic process, and that is likely the best way to learn it, but having a resource that is written more from the perspective of dynamical systems than a physicist would speed the process up quite a bit!

Re: A room-temperature superconductor? New developments

#649

Post by Karrot_Kream »

XorNot wrote: post #612
fsh wrote: post #516

Earlier quoted context omitted.

None of the things you listed are limited by the conductors in them. The efficiency of high voltage AC power lines is limited by capacitive coupling to ground. Battery charging is limited by the cell chemistry. CPU heat output is limited by the resistance of the semiconductors. Turns out metals (in particular copper) are already incredibly good conductors.

Superconducting powerlines would be able to transport DC electricity with 0% losses. To put this in context: you could put solar panels in California, and send every watt of power to Alaska or New York, while losing nothing in the transport.

The superconducting effect of LK99 seems to top out at around 150 mA / cm^2. Maybe more research will bear fruit here, but for now we're not looking at HVDC lines.

Re: A room-temperature superconductor? New developments

#650

Post by feoren »

xwdv wrote: post #482

What’s the next big tech in the tech tree after room temp superconductors?

Applied Relativity (Discover 5), then Photon/Wave Mechanics (Conquer 6), Probability Mechanics (Build 7), and Nanometallurgy (Explore 8). Once we also discover Organic Superlubricant (Conquer 7), we'll get to Matter Compression (Conquer 9).

Organic superlube!? Oh, it's great stuff! Great stuff.

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