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A room-temperature superconductor? New developments

science.org

621–630 of 821 posts

Re: A room-temperature superconductor? New developments

#621
post #390

Earlier quoted context omitted.

Hang on, wouldn't a sliver of any magnetic material behave like this within a moving magnetic field? This replication is a fail, yes?

A magnetic material would orient itself to the magnet, and then move towards the magnet, not get "stuck" in its fields.

Is this somehow incorrect?

Getting "stuck" in a magnetic field is called "Flux pinning", which is what we're seeing here, from what I understand: https://en.wikipedia.org/wiki/Flux_pinning

Magnetic material can't do this. They're attracted. As some of the videos have shown, with large magnets placed next to the samples, they are not attracted.

Re: A room-temperature superconductor? New developments

#622
post #550

Earlier quoted context omitted.

There is a theory that with room temperature superconductors you could use an inductor for practical energy storage.

what are the practicalities of storing enormous magnetic fields and then collapsing them to draw power? that seems...not obviously a good idea.

Well, exactly. While there is a way of getting some of the stored energy as an controlled power, most of the failure modes of such a thing leads to uncontrolled release of the stored energy, manifested by the whole thing just somewhat instantaneously turning into very hot gas.

Re: A room-temperature superconductor? New developments

#623

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…

>The ramifications of the inflection point we are currently at is mind boggling.

No joshing, I just got done posting this on facebook: "If this is practical it will change the world like the transistor; maybe more."

Re: A room-temperature superconductor? New developments

#624
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

Nah, the GP is just completely out of reality. We won't see lossless transmission in a very long time, and no place where an aluminum cable is too expensive today will become viable because something a million times more expensive is 9% more efficient. Batteries won't see a revolution because of this, there's simply no reason for them to (but they are currently in a revolution, and there are more to come). AC storage…

[deleted]

Re: A room-temperature superconductor? New developments

#625
post #516

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.

> CPU heat output is limited by the resistance of the semiconductors.

Technically true but not applicable... Super conducting CPUs already exist (at below room temp), and they don't use semiconductors. They don't have an exact transistor equivalent but use digital logic circuits such as Quantum Flux Parametron (QFP) and rapid single flux quantum (RSFQ), which are comprised of Josephson Junctions [0] which are made from the same super conducting material. Relying on quantum effects of a gap between two conductors rather than specific material properties.

So while it is true that CMOS are limited by the resistance of both the conductor interconnects AND the semiconductors. Super conducting circuits only appear to need a conductor... There are other drawbacks, such as larger feature sizes due to the nature of super conducting materials, and QFP and RSFQ might be more complex? but this is potentially offset by huge advantages: zero resistance buys not only power efficiency and minimum heat generation (as required by landauer limit), but also allows circuits to be driven at a higher clock, so far demonstrated to 770GHz for one CPU [1]

[0] https://en.wikipedia.org/wiki/Josephson_effect

[1] https://spectrum.ieee.org/superconductor-logic-goes-lowpower

Re: A room-temperature superconductor? New developments

#626
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

Nah, the GP is just completely out of reality. We won't see lossless transmission in a very long time, and no place where an aluminum cable is too expensive today will become viable because something a million times more expensive is 9% more efficient. Batteries won't see a revolution because of this, there's simply no reason for them to (but they are currently in a revolution, and there are more to come). AC storage…

>This won't replace metal layers in CPU for a really long time. Superconductors are hard enough to make, CPUs are absurdly hard to make, and the wins on power savings aren't very large. If people make superconducting chips, it will be ones where the superconductors do active switching, what is much farther away and can enable much faster CPUs too.

I would've thought the main wins would've been reduced heat generation. Like you said, power savings would be negligible. But at the data center scale I'd imagine that reduced heat would result in reduced air conditioning power costs. And potentially with thermal constraints removed, it would allow for more compact packaging per server as well.

Like you said though, I doubt it would happen any time soon.

Re: A room-temperature superconductor? New developments

#627

Earlier quoted context omitted.

It might even all come fast enough to save us from climate change (But I'm not getting my hopes up)

we already know how to stop climate change: actually stop burning shit and deploy existing technologies quickly. the problem is lack of will, not lack of technology. corollary: anyone trying to say we need fancy new technologies like fusion/superconductores/supercapacitors isn't actually very interested in stopping climate change.

There are much more effective ways to geo-engineer earths climate. Their problem is the politics that surround all the options. Sooner or later we won't have other options.

Re: A room-temperature superconductor? New developments

#628
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

Nah, the GP is just completely out of reality. We won't see lossless transmission in a very long time, and no place where an aluminum cable is too expensive today will become viable because something a million times more expensive is 9% more efficient. Batteries won't see a revolution because of this, there's simply no reason for them to (but they are currently in a revolution, and there are more to come). AC storage…

> something a million times more expensive

Lanarkite and copper phosphide aren't expensive, other than the government controls on red phosphorous (because it can be used to make meth).

Re: A room-temperature superconductor? New developments

#629
post #497

Earlier quoted context omitted.

> 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.

"Hoverboards don't work on water!!"... or any non-magnetic surface :)

Re: A room-temperature superconductor? New developments

#630

Earlier quoted context omitted.

Timelines matter. The BS will either return the millions in a couple years or it won't. Basic research may return much more, but your best case is still many years before you gets results. The risk is actually higher with basic research than for BS as well - the pet rock earned money and there are plenty of other examples of stupid things working well quickly. Basic research in fusion hasn't returned anything yet eve…

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.

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