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The first room-temperature ambient-pressure superconductor?

arxiv.org

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Re: The first room-temperature ambient-pressure superconductor?

#821

Post by klyrs »

tomxor wrote: post #799
nick__m wrote: post #506

Earlier quoted context omitted.

Superconductivity is not enough for a cpu that doesn't generate heat, you would need a cpu built of reversible logic gate. Thermodynamics requires that when you destroy a bit of information you generate at least 2.9×10−21 J. It's the Landauer's principle.

It turns out that some people are already combining this principle by making adiabatic superconductor microchips! https://spectrum.ieee.org/new-superconductor-microprocessor-... I don't think this actually affects the high level opcodes, i.e it's transparent, so long as the circuit implementing them somehow performs charge recovery, the high level programming can still appear to be irreversible (I don't want to think…

Reversible logic is fun, but the memory requirements get intense. You need enough storage to retain every intermediate value used in a computation. If you have a 1GHz 64-bit processor and it does an hour-long computation, you need to store the entire 29TB history of its intermediates... and then spend an hour unwinding it!

But currently, the adiabatic chips has a bigger issue with getting to zero: their control circuitry is a bank of AWGs, each burning probably hundreds of watts at room temperature. They ideally don't produce heat in the cold zone, which is great for the cryogenic system, but if we have room temperature superconductors, that's suddenly moot.

Re: The first room-temperature ambient-pressure superconductor?

#822

Post by CamperBob2 »

legi0nary wrote: post #816
h0l0cube wrote: post #538

Earlier quoted context omitted.

> numerous self-serving decisions And much of the cost of nuclear is hedging against these decisions, whether by profit-seeking or the tyranny of a totalitarian state

No? Not really? International standards exist

Unfortunately they have a point, in that there is no ISO or DIN standard that covers a plant that has been rigged with explosives by invading barbarians.

The solution isn't to abandon nuclear power, but to make it very costly for aggressors to meddle with it. E.g., deploy UN forces to the plant at the first sign of trouble.

Re: The first room-temperature ambient-pressure superconductor?

#823

Post by beambot »

jacquesm wrote: post #456
andreiklochko wrote: post #389

Guys, even if everything in this paper is true, the material as it is might have limited applications. From what they show, the critical field and critical current seem very low. 2500 Oe is like 0.25 Tesla. Even REBCO at 77K is >1T. And 2500 Oe is not even at critical temperature but much lower. From skimming through the article I couldn't find the sample size of the current measurement to get the critical current de…

This is a dancing pig. The thing to appreciate is not how well it dances but that it dances at all .

Riff on this: When your product is a monkey reciting Shakespeare while standing on a box in Central Park, you don't start by building the box.

Re: The first room-temperature ambient-pressure superconductor?

#824

Post by hinkley »

Jolter wrote: post #715
hinkley wrote: post #307

Earlier quoted context omitted.

What do you suppose the odds are that there's a Tin-based compound instead of lead based? (Which would effectively make a bizarre form of brass a superconductor)

Bronze, right? Brass is copper and zink.

I swear I typed bronze…

Re: The first room-temperature ambient-pressure superconductor?

#825

Post by qnleigh »

carabiner wrote: post #671

Read this comment thread from SC researchers: https://www.reddit.com/r/worldnews/comments/159g2k4/comment/... Lots of problems with the paper, they claim. It is not up to the standards of current SC research. One of them says Dias's work shows more merit than this.

His criticism of figure 1b doesn't seem reasonable to me, given that the are resistance measurements in 1a and 1c that show zero resistance coming and going in roughly the expected way as a function of temperature and magnetic field. Unlikely that the connections would break and reconnect in just the right way.

Nevertheless I'm still quite skeptical.

Re: The first room-temperature ambient-pressure superconductor?

#826

Post by meindnoch »

weard_beard wrote: post #576
meindnoch wrote: post #309

Ah, I see, they decided to start leaking some of the alien stuff they recovered from UFO crash sites in the 50s.

Only the bits that fix climate change (better batteries, lossless transmission)

Yeah. The Greys gave permission to fix the planet, but anti-gravity won't be released until humanity becomes peaceful.

Re: The first room-temperature ambient-pressure superconductor?

#827

Post by A_D_E_P_T »

Ajedi32 wrote: post #800
giarc wrote: post #789

Earlier quoted context omitted.

Those are two I see mentioned the most often (MRI and maglevs). To be honest though, those are great things to improve (especially the MRI), however, the amount of hype in this thread and on the internet tells me there must be more than just improved MRI and better trains....

I think a big part of the reason there's so much hype around this is that room temperatures superconductors have long been a famous, almost legendary undiscovered material in popsci. Theoretically possible, but with no proof that any such material actually exists. But now not only is this paper claiming that such a material exists, but also that they made some, and it's easy to manufacture and works at temperatures w…

> Theoretically possible, but with no proof that any such material actually exists.

I wouldn't say that it was necessarily "theoretically possible," for there has never been, and there still isn't, a grand theory of how any given material's atomic/crystalline structure relates to superconductivity. In other words, with no theory of material superconductivity, it was never quite clear what's possible and what isn't. With this new material, though, we might get a lot closer to a working model, if nothing else.

Re: The first room-temperature ambient-pressure superconductor?

#828

Post by ClumsyPilot »

jacquesm wrote: post #756
ClumsyPilot wrote: post #755

Earlier quoted context omitted.

> superconductors ... have the potential to change the world in ways that would be hard to even imagine. Such as? I do not see how superconductors help with the challenges of Climate Change, food insecurity or danger of nuclear war. What will be the change for the average Joe? Maybe a better electric car?

Energy storage and distribution alone can affect all three of your examples and they are very trivial ones. Then there is medicine, possibly a better shot at fusion and so on. Better electric cars are at the bottom of my wish list (because they're still cars). But yes, those too (much lighter but more powerful motors means you can do away with the drive train completely and it would also allow you to get rid of the b…

okay, could you be more spesific - what kind of improvement can we expect in storage? Is the improvement measurable - like will I be able to buy more kilowathours of storage per dollar?

Re: The first room-temperature ambient-pressure superconductor?

#829

Post by floxy »

lucubratory wrote: post #616
arnaudsm wrote: post #289

Exciting paper. I hope this won't be the same scenario as the other team that claimed a room-temperature superconductor in 2020 and was later proven to be a fraud. https://www.nature.com/articles/d41586-023-02401-2

The other team had a very complex to evaluate claim about the specific data indicating superconductivity, and the methodology required a lot of pressure and was quite difficult to replicate (and ultimately, of course, impossible, as the results were false). The claims in this case are very simple to understand and very consistent with superconductivity, demonstrated on a macro scale at normal pressures and temperatur…

>If it's true, people will have replicated this within a couple of weeks, which would be mostly sourcing materials.

I wonder how much it would cost to try and replicate this, in materials, labor costs, and vacuum furnace time/costs. My naive guess is that that labs in general aren't just going to drop everything to try an replicate every instance of someone declaring they've discovered room temperature superconductivity. Seems more like a "there's a lull in paying work, so hey, why don't some of you junior technicians try this out" thing? Anyone have insight into this? I suppose a university lab might have more leeway here to try out spur of the moment experiments? Maybe this is a "I'm personally interested in this and I'll work in the evenings to test it out, instead of on company/university time"?

Re: The first room-temperature ambient-pressure superconductor?

#830

Post by amatecha »

amatecha wrote: post #353
JumpCrisscross wrote: post #341

Earlier quoted context omitted.

> the use of lead would restrict the use cases Most people aren't licking the insides of their computer processors, fusion reactors, radio telescopes and MRIs.

It's more about producing toxic waste and contaminating the environment - no one's licking the solder joints in their electronics either, but you still have to use lead-free solder. For instance in EU, https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A... Canada, https://www.canada.ca/en/health-canada/services/environmenta... USA, https://www.epa.gov/lead/learn-about-lead

Why is this being downvoted into oblivion? It's a completely valid, good-faith point explaining why lead has restrictions on its uses other than "someone might lick it"... It would be nice if people actually responded and vocalized their disagreement or described the flaws in my reasoning, rather than just suppressing my message.
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