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A room-temperature superconductor? New developments

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Re: A room-temperature superconductor? New developments

#471

Post by floxy »

_yb2s wrote: post #189
elfbargpt wrote: post #77

Earlier quoted context omitted.

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.

I don't get the "disappointment" with USA scientists in this thread not having yet published a replication. There has only been one weekday since the LK-99 revelation came to light. Have some patience. The analysis from this article is a publication from Berkeley National Lab that has already come out, and Argonne National Lab has announced they have synthesized the material as of yesterday and will release results f…

>There has only been one weekday since the LK-99 revelation

The original paper drop was July 22nd.

https://arxiv.org/abs/2307.12037

Re: A room-temperature superconductor? New developments

#472

Post by tigershark »

derefr wrote: post #453
armarr wrote: post #446

Earlier quoted context omitted.

Sure, it would make the wiring smaller and more efficient. But I also don't see how it would help in the chemical energy transfer to charge the battery.

What I was trying to say is, with some battery chemistries, the current (heh) limiting step for charging speed is the wiring into, and of, the battery, rather than the safe reaction speed of the battery chemistry itself. We could safely "crank the chemistry" by an order-of-magnitude or more if we could get the desired current into the battery without the wires+electrodes conducting undue amounts of heat into the elec…

No, it’s not. It’s the chemical reaction the limit. In li-ion for example you will create dendrites when charging/discharging too fast or too deep. This is the cause of the relatively short cycle life.

Re: A room-temperature superconductor? New developments

#473

Post by jacquesm »

empath-nirvana wrote: post #466
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…

> Much faster with no heat to burn your lap. Computation inherently creates heat, that's not something that superconductors will change.

This is repeated over and over again but that's only a very small fraction of the kind of power that a computer uses. By the time you're talking about reversible computing all the low hanging fruit has been plucked and there are much, much bigger sources of loss. The biggest one impacted by superconductivity if (and that's a really big if) it can be used for the interconnect layers ('metal') in a chip and for the circuit traces outside of the chip that you can cut the charge and discharge time for the gates of the transistors in the chip down to a minimum. This in turn changes the power consumption of the chip because the transistor is either 'on' or 'off' and spends much less time on the transition in between where it is more of a resistor than a switch.

So it isn't determined whether or not it will be changed but it could be.

Re: A room-temperature superconductor? New developments

#474

Post by westurner »

empath-nirvana wrote: post #466
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…

> Much faster with no heat to burn your lap. Computation inherently creates heat, that's not something that superconductors will change.

Flipping a bit from 1 to 0 releases heat (because you can't just drop the 1 onto the negative/ground)

Resistance in non-super- conductors wastes electricity as heat.

From "Thermodynamics of Computation Wiki" (2018) https://news.ycombinator.com/item?id=18146854 :

> "Quantum knowledge cools computers: New understanding of entropy" (2011) https://www.sciencedaily.com/releases/2011/06/110601134300.h...

>> The new study revisits Landauer's principle for cases when the values of the bits to be deleted may be known. (with QC)

Re: A room-temperature superconductor? New developments

#475

Post by taberiand »

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…

It might even all come fast enough to save us from climate change

(But I'm not getting my hopes up)

Re: A room-temperature superconductor? New developments

#476

Post by sorokod »

bluGill wrote: post #397
javajosh wrote: post #198

Earlier quoted context omitted.

Good idea! They wouldn't have been able to do any applications without a voltaic cell, and it would have been a novelty. Like gunpowder in ancient China.

The Chinese invented cannons about the time they invented gun power. However by coincidence their forts used stone walls thick enough to resist cannon fire and so it was not really better than the various catapult systems they also had (which also couldn't breach their fort walls). https://acoup.blog/2021/12/17/collections-fortification-part... Goes into this in more detail for a couple paragraphs.

Shooting in steep trajectory, howitzer style, would still be valuable.

Re: A room-temperature superconductor? New developments

#477

Post by mikro »

empath-nirvana wrote: post #466
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…

> Much faster with no heat to burn your lap. Computation inherently creates heat, that's not something that superconductors will change.

https://en.wikipedia.org/wiki/Landauer%27s_principle

The heat can be reduced by factor of a billion or so.

Re: A room-temperature superconductor? New developments

#478

Post by jacquesm »

derefr wrote: post #432
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

Resistance is what makes things hot, and heat is what makes dumping huge amounts of charge current into batteries a bad idea. No resistance → no heat → no need to charge with low current†. Another way to say it is that, with a superconducting wire, you can make the wire as thin as you want and still pass the same amount of current through it, without melting the wire. Picture using a USB-C cable to charge your car. †…

> you can make the wire as thin as you want

No, superconductors have a specific current above which they stop superconducting so you will want to stay away from that limit. This particular superconductor has been presented with a very low Ic (150 mA in the original paper0 which would not make it particularly useful in such applications but future iterations (assuming it is all true) may improve on that (they should otherwise we have the equivalent of a superconducting straw).

Re: A room-temperature superconductor? New developments

#479

Post by wilg »

lolinder wrote: post #398
wilg wrote: post #276

Earlier quoted context omitted.

Genuinely a laugh-out-loud take on mainstream science reporting.

I took it as saying "they usually jump in too early, so this is a refreshing change of pace."

Oh yes, you’re right, I think I read it too quickly.

Re: A room-temperature superconductor? New developments

#480

Post by floxy »

0xDEF wrote: post #260
fallingknife wrote: post #49

Earlier quoted context omitted.

Why are they all from China? Why are they able to replicate so much faster than US labs?

Because there has literally only been 2-3 weekdays since the LK-99 revelation. Do you expect American and European scientists to work during weekends?

The original paper dropped July 22nd:

https://arxiv.org/abs/2307.12037

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