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A room-temperature superconductor? New developments

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Re: A room-temperature superconductor? New developments

#631

Post by AlotOfReading »

Veserv wrote: post #405
ASalazarMX wrote: post #305

Earlier quoted context omitted.

The force of tradition is amazing. Imagine centuries knowing how to make something that explodes violently, and using it for entertainment instead of weapons. Just like how Mesoamerican civilizations invented the wheel, but only used it on children toys and not for transportation. There were no draft animals in the region, but they didn't even make wheelbarrows. https://www.mexicolore.co.uk/aztecs/home/the-concept-of…

The Mesoamerican civilizations did not have copper, bronze, or iron metallurgy which is a prerequisite for making the metal rims needed for transportation wheels. A wooden wheel without a metal rim is too fragile for transportation. Without the wheel, humans are actually relatively comparable to other pack animals in carrying efficiency. It is the wheel that makes moving larger loads more efficient which makes it adv…

Bronze was extremely common in Mesoamerica for household goods like needles and fishhooks. Copper was also common, but mainly for ceremonial and ornamental objects like bells.

As for wooden wheels being too fragile, you can build a perfectly good wheel without metal bands. It's simply going to be heavy and annoying if you're trying to run a wagon to Oregon.

Re: A room-temperature superconductor? New developments

#632

Post by DesiLurker »

MillionOClock wrote: post #94

If it's real, how fast could we see concrete applications using this material? 5-year time frame? 10-year time frame? More?

if its real (or real even in principle as in hard to repro say 1 in 20 times) even than the immediate consequence would be a lot of investment directly flowing into the research. combining that with some AI based techniques I'd say (if the idealized material bears out predictions at room temp) within half a decade we will see good manufacturing techniques. after that its all application specific.

Re: A room-temperature superconductor? New developments

#633

Post by cogman10 »

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.

And to this point, HVDC has been slowly rising as a viable alternative beyond just undersea transmission.

A mistaken belief is that AC is more efficient than DC. What AC is is more easy to transform from one voltage to another (until somewhat recently). That makes it easier to run AC at 1 MV and then step it down to 240V for residential applications.

The cost is as AC voltage goes up, capacitive resistance increases. This is part of the reason why high voltage lines have such huge towers with the lines far apart.

An HVDC line, however, can be put underground (or water) without suffering power losses. It's voltage can go well above that of AC voltages with the only limit being how much insulation we need for the line.

Super conductors are nice, but only in the "now we can run 1 billion amps at 100V" sense to avoid the capactive resistance. Without any sort of special materials you get most of the benefits of super conductors by using HVDC. The only real downside is high voltage DC is still super dangerous. Cut the insulation and you've got something that can arc meters whereas a superconductor at lower voltages would be about the same danger as any other conductor at lower voltages.

Re: A room-temperature superconductor? New developments

#634

Post by marshray »

Melatonic wrote: post #486
marshray wrote: post #278

Earlier quoted context omitted.

Neither lead nor copper are what we would normally consider a "magnetic material" like iron. That it interacts strongly with a magnetic field shows that a big change in the material, consistent with superconductivity, has occurred. Quantum level effects are newly appearing in the macroscopic world, and that's always interesting.

Could this not also have a big use case outside of superconductivity? Decellerators or accelerators for maglev trains or similar?

Oh, definintely!

Most materials are diamagnetic, but only very weakly so.

I think that a new room-temperature material that was so strongly diamagnetic that it could lift the weight of its own volume in lead probably would bring some interesting new applications.

Re: A room-temperature superconductor? New developments

#635

Post by crooked-v »

ChrisClark wrote: post #470
jychang wrote: post #459

Earlier quoted context omitted.

> Less than 40kJ/L

Pretty sure that includes the volume of the entire cooling system needed to keep it superconducting.

The entire reason the current (possible) discovery may be revolutionary is that it doesn't need a cooling system.

Re: A room-temperature superconductor? New developments

#636

Post by dralley »

anonylizard wrote: post #630
dralley wrote: post #468

Earlier quoted context omitted.

See, the thing is, you're making an argument about how VC works, and I'm making an argument about allocation of money towards VC vs. other socially beneficial projects. I understand how VC works. I'm annoyed that - let's even take the Saudis as an example, since they fund half of Silicon Valley anyway - would rather flush their money down the drain on stupid shit than do long-term projects that may help secure their…

Saudis don't fund half of Silicon Valley. Aramco is worth 2 trillion, apple alone is worth 3 trillion. Saudis have built entire top-equipment universities out of nothing (KAUST), and hired top foreign professors, and offered generous scholarships to foreign students to fill it up. You rant about short termism, but don't seem to like doing research yourself.

This is a discussion about VC specifically, Apple isn't relevant. The Saudis are large backers of many of the largest VC firms.

Re: A room-temperature superconductor? New developments

#637

Post by sharlos201068 »

qsdf38100 wrote: post #605
tmpX7dMeXU wrote: post #596

Earlier quoted context omitted.

Who said infinite power?

It's implied by instant charging. The power would be the battery capacity divided by 0.

No one means literally zero time to charge. A couple seconds compared to minutes or hours is virtually instant for practical purposes.

Re: A room-temperature superconductor? New developments

#638

Post by zetazzed »

elfbargpt wrote: post #77
7moritz7 wrote: post #17

Earlier quoted context omitted.

I have seen three now from China alone. Plus a calculation from some respected institute from today that confirms the theory

Throughout this whole saga I've had this feeling that at the very least we can rely on China to really pursue this new development to it's logical end. It's kind of sad, but I don't think I can say the same about the US at this moment. You know for a fact China's going to JUMP on this, figure out if it works or not, and iterate.

This should be a happy moment for the way global science works! Researchers in Korea wrote a paper. American, European, and Chinese theorists in Berkeley and Shenyang analyzed the approach right away and confirmed its hypothetical viability. Now another team in Huazhong is conducting replicating experiments. All in the matter of about a week! This kind of open collaboration is helping us all go faster, and it doesn't have to become a cause for nationalism.

Re: A room-temperature superconductor? New developments

#639

Post by contravariant »

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.

Yeah at those kinds of scales I get doubtful. At those scales the electrical fields themselves begin to exert inertia on things, to the point that you could cut most power lines and they wouldn't stop catastrophically, they'd continue catastrophically (a problem that only gets worse with superconductors, as happened to CERN when they accidentally vaporised a length of superconductor that had become conductive).

It could definitely open up the road to long distance high capacity power lines, but somewhere along the line reality is going to make things difficult. It's not magic after all, just sufficiently advanced technology.

Re: A room-temperature superconductor? New developments

#640

Post by crooked-v »

marshray wrote: post #634
Melatonic wrote: post #486

Earlier quoted context omitted.

Could this not also have a big use case outside of superconductivity? Decellerators or accelerators for maglev trains or similar?

Oh, definintely! Most materials are diamagnetic, but only very weakly so. I think that a new room-temperature material that was so strongly diamagnetic that it could lift the weight of its own volume in lead probably would bring some interesting new applications.

For example, anything with a bearing in it used in an application where it's safe to have a strong permanent magnet.
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