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A room-temperature superconductor? New developments

science.org

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Re: A room-temperature superconductor? New developments

#801

Earlier quoted context omitted.

What should the headline be? "South Korean scientists claim room temperature superconductivity again! Are they lying like their last paper? Let's celebrate!"

"Potential superconductor breakthrough sends national labs scrambling"

Nature published their last big superconductor claim and then had to retract it. Publications getting burned by these folks makes them understandably reluctant to get worked up again.

Re: A room-temperature superconductor? New developments

#802
post #497

Earlier quoted context omitted.

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 :)

[deleted]

Re: A room-temperature superconductor? New developments

#803
post #700

Earlier quoted context omitted.

breakthroughs since fire more important than the transistor probably include cooking, agriculture, the wheel, metallurgy, glass, ceramics, the heat engine, mechanisms in general (with things like pulleys, hydraulics, screws, and gears), construction cement (originally lime), math, writing, optics, electricity, chemistry (including things like distillation, the atomic theory, and recrystallization), plumbing, carpentr…

The mass-energy equivalence and how it led to the discovery of nuclear fission/fusion and how to control/cause explosive atomic chain reactions was probably one of the most impactful technologies of all time, in a literal sense.

maybe, but it's not yet in the same league as math, writing, cooking, sewing, and electricity, in terms of its effects on human life

i mean all five of those were probably prerequisites for it?

maybe if the humans build torchships or nuclear-powered starships, or convert the electric grid to mostly nuclear, i'd agree, but those all seem far in the future

Re: A room-temperature superconductor? New developments

#804
post #803

Earlier quoted context omitted.

The mass-energy equivalence and how it led to the discovery of nuclear fission/fusion and how to control/cause explosive atomic chain reactions was probably one of the most impactful technologies of all time, in a literal sense.

maybe, but it's not yet in the same league as math, writing, cooking, sewing, and electricity, in terms of its effects on human life i mean all five of those were probably prerequisites for it? maybe if the humans build torchships or nuclear-powered starships, or convert the electric grid to mostly nuclear, i'd agree, but those all seem far in the future

I'm curious: why sewing in particular? As opposed to say spinning or weaving or knitting?

Re: A room-temperature superconductor? New developments

#805
post #797

Earlier quoted context omitted.

> people do sometimes steal paper to recycle it > they are the cartoneros, because what their carts are usually piled high with is cardboard, cartón Paper, or coardboard? It's unclear whether you're referring to cardboard as paper, because after your assertion the only thing possibly linked to it in the rest of the comment is your references to cardboard. Cardboard is not paper. They share base components, but referr…

mostly cartoneros recycle what the biz refers to as corrugated fiberboard, which most people call cardboard in english. it's made of paper and glue there are different kinds of paper, which require different recycling streams; cartoneros will accept some others but not all your talk about 'losing the thread' makes me think you are playing some kind of game where the objective is not to find out what the truth is but…

> refers to as corrugated fiberboard, which most people call cardboard in english. it's made of paper and glue ... there are different kinds of paper

Isn't that exactly the point I just made? I'm confused as to why you're restating it. In English nobody is going to mistake someone that makes a statement about "paper" as talking about "cardboard", whether they're referring to corrugated fiberboard or plain fiberboard (which are both often referred to as cardboard depending on whether the context is arts, crafts or something else).

> your talk about 'losing the thread' makes me think you are playing some kind of game where the objective is not to find out what the truth is but to sound convincing even if what you are saying is false

If you look at my original comment, what I said about paper is purely an example to illustrate that commonly recycled doesn't necessarily mean worth supporting harvesting for base materials. Many other things go into that assessment (such as whether the base material can be easily separated from other materials and how its cost to transport affect any possible profit that might motivate people to do so.

That you refuted that example by using an entirely different material seems to either be a non-sequitur or misguided. While presented as a counterpoint, it doesn't really seem to affect the claim I was making at all.

That is what I meant by it lost the thread. It didn't really add to the conversation at hand usefully in the way it was presented. If it was presented as an interesting factoid about recycling and cardboard, which is related to paper, that would be one thing, and I would fully support it. But as to whether it means something that can be/is recycled will be scavenged for profit in all cases, I don't think it really says anything one way or the other, and that was what I was trying to convey.

If you're trying to say that paper itself as what any native English speaker would assume we're talking about if they read it, and not just cardboard, is also profitable to recycle and people collect and turn that in for profit then please clarify that point. Otherwise, while an interesting fact, and I'm happy to now know it, I'm not sure it actually affects what I was trying to communicate originally in any way.

Re: A room-temperature superconductor? New developments

#806

Earlier quoted context omitted.

> so far demonstrated to 770GHz for one CPU That's not a CPU, it's a simple circuit. From the article, "Simple superconducting logic circuits have been shown to operate at speeds of up to 770 gigahertz." Exotic semiconductor transistors can switch that fast, record being over 800GHz I think. Regular transistors of the type in your phone can probably do around 200-300GHz. Not to say there could not be revolutionary de…

I doubt that regular cellphone transistor can _switch_ at 200Ghz; their GBW might be in that range, but for reliable switching you need clock frequency at most 1/10 of GBW

They can, as calculated by switching delays of simple circuits like inverters and NANDs (so simpler than a FO4).

Actually it's probably more like 200 than 300, I haven't seen 3nm models but transistors are still getting faster.

Re: A room-temperature superconductor? New developments

#807
post #768

Earlier quoted context omitted.

We’re not talking about charging existing batteries but superconductors where you just “trap” large amounts of electricity in the superconductor for future use.

Unfortunately magnets put forces on themselves, which means you’re limited to storing up to about as much energy as it would take to break the thing making the field; or, to put it another way, it’s about the same range of energy densities as springs or rubber bands. Earlier discussion: https://news.ycombinator.com/item?id=36954783

Does that mean you would get equal(but probably insanely more dangerous) performance with a giant miles long spring instead of the proposed superconducting loops?

Re: A room-temperature superconductor? New developments

#808

Earlier quoted context omitted.

> CPU heat output is limited by the resistance of the semiconductors. Can't superconductor help here?

Only a little, one big limitation in chips is RC wire delays (the distributed capacitance along a wire needs to be charged/discharged for a signal change to pass) - due to edge effects capacitance doesn't scale with the area of the wire - but R does (inversely so wires have gotten slower) - so as chips have got denser wires have not got faster at the same rate, when I first started building chips we mostly only cared…

I'm surprised anyone is even trying that hard to make faster CPUs anymore, now that they're already so fast. You'd think everything would be done by GPUs or dedicated accelerators by now. Especially when so much of the internet is pretty much just serving video files.

But yet there's still so much that could be accelerated even with current hardware, but isn't.

Re: A room-temperature superconductor? New developments

#809
post #803

Earlier quoted context omitted.

The mass-energy equivalence and how it led to the discovery of nuclear fission/fusion and how to control/cause explosive atomic chain reactions was probably one of the most impactful technologies of all time, in a literal sense.

maybe, but it's not yet in the same league as math, writing, cooking, sewing, and electricity, in terms of its effects on human life i mean all five of those were probably prerequisites for it? maybe if the humans build torchships or nuclear-powered starships, or convert the electric grid to mostly nuclear, i'd agree, but those all seem far in the future

Yes, I did mention "one of"

Re: A room-temperature superconductor? New developments

#810
post #772

Earlier quoted context omitted.

Because there's more to life than money. For King and Country.

"King" and "Country" sound like paying taxes and dying in a war for profit, i.e., someone else's priorities, no thanks. Betterment of human existence, preservation of habitable environment, etc, those are bigger than the self.

It's a saying referring to having pride in the nation you live in. Make your country's status in the world just a tiny bit higher. Win a Nobel Prize for your country. Win the Olympics for your country. The US is not big on collectivism and that's okay. Other countries do things differently.
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