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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?

#581

Post by lilgreenland »

lilgreenland wrote: post #272
solarmist wrote: post #263

Earlier quoted context omitted.

The effect is weak, but seeing that it behaves the same by flipping the magnet means that it can't be a standard magnet like we're used to seeing. (If I understood some of the other comments correctly). Other comments. https://news.ycombinator.com/item?id=36867758

Copper does this already. It's not like ferromagnets. https://www.youtube.com/watch?v=sENgdSF8ppA

Well after seeing the second video I'm pretty convinced it's superconductive or a good scam. The effect was probably just not strong enough in the first video.

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

#582

Post by achr2 »

tinco wrote: post #488
ahlCVA wrote: post #313

Earlier quoted context omitted.

This seems to be the corresponding video (linked in the associated media tab on arXiv): https://sciencecast.org/casts/suc384jly50n

Is there an alternative explanation possible for the video? Couldn't it just be a magnetized piece of ferrite that is magnetized in a weird way causing it to lift up like that on a strong magnet?

Pyrolytic graphite looks exactly like this and behaves in exactly this way (without being superconducting) as long as one side is anchored. With a careful array of magnetic poles, graphite will levitate at room temperatures.

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

#583

Post by PBnFlash »

achr2 wrote: post #573

This is almost certainly a sham. I had hopes before watching the videos, but the only effects shown are normal paramagnetism (from the copper substrate) and diamagnetism (pyrolytic graphite).

I thought the same thing, if these "sister" papers being posted are real these are not convincing results.

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

#584

Post by arjvik »

ChadNauseam wrote: post #579
arjvik wrote: post #517

Earlier quoted context omitted.

Say we use this (or any other) superconductor to build an AND gate. Assume one input is zero, so the information of the other input is lost. I assume the energy lost as heat occurs due to the "current" going into the and gate having "nowhere else to go" other than to dissapate as heat? If that's the case, simply redesigning our logic gates to have as many outputs as they have inputs, with some of these outputs feedin…

> I assume the energy lost as heat occurs due to the "current" going into the and gate having "nowhere else to go" other than to dissapate as heat? Not quite, it's a thermodynamic principle that applies to any way you could possibly compute AND. Basically, the laws of physics are reversible, so your computation must be reversible too. There are 4 possible inputs to an AND gate, so to be reversible there must be 4 pos…

I think we're talking about the same thing, but I explained it absolutely terribly.

If we "dump the other output" back into the power source, such as the battery, does that solve the problem of not implicitly dumping it into the environment? Or is it still destroying information?

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

#587

Post by jacquesm »

Turskarama wrote: post #574
jacquesm wrote: post #546

Earlier quoted context omitted.

There are plenty of commercial applications of hydrogen fuel cells though. The biggest issue has been pretty much a constant over the time since it has been invented: keeping the membranes free from impurities is hard. But there are all kinds of transportation devices using hydrogen in production today.

Sure, but the point is that they hardly caused a revolution in energy storage. If fuel cells didn't exist, for the average person life would be exactly the same. Revolutionary tech does change normal peoples lives, and sometimes very rapidly, but a lot of stuff that looks revolutionary just kind of never works out. I'd say nuclear power is probably the prime example of this. It was supposed to bring us electricity to…

Fuel cells are just another transformer like the dynamo, or any kind of motor. They turn one kind of energy into another and in the context of hydrogen (which you could produce out of water using electricity as a means of storing energy) it serves to reverse the storage step. This is nice to have but just like nuclear power it's a variation on stuff that we already have, it is at best a quantitative change (and hopefully an improvement).

Room temperature / ambient pressure super conductivity is something we do not currently have. The difference between having that and not having that is a qualitative difference and hence it will enable a whole raft of applications for which we currently do not have a solution.

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

#588

Post by PBnFlash »

hatsunearu wrote: post #455

I don't have any proof of this other than "vibes", but I read through the Korean website for their research lab and I'm getting major scam vibes: https://qcentre.co.kr/ Hard to put it into words, but there's something that just doesn't feel right--I'd be very skeptical of these results.

Yeah, that and the videos people are posting are really underwhelming.

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

#589

Post by eterevsky »

ralfn wrote: post #67
eterevsky wrote: post #51

Earlier quoted context omitted.

> the biggest scientific discovery of the last hundred years I would say that electronic computers would take take the first spot for me, but I don't deny that room-temperature superconductors would be pretty close to the top.

Computers were invented long before they became invented. So that wouldn't be in the last 100 years. However unlike computers, if this idea works, it will get productized quickly.

I wrote electronic computers: a bunch of technologies like transistor and integrated circuits.

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

#590

Post by tomxor »

pezezin wrote: post #555
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.

My understanding is that modern CMOS circuits dissipate around 1 pJ (10^-12) per bit, so even if we are limited by the Landauer's principle, it would still be a 9 orders of magnitude improvement. I would surely love a CPU that uses microwatts instead of hundreds of watts.

Yup, the current dominating factor is resistance, not the Landauer limit.

Biological systems supposedly operate at about one order of magnitude above the Landauer limit [0], i.e this is completely practical and has been happening before we even made computers... we probably wouldn't exist without being this efficient, imagine how much energy our cells would need to consume and emit as heat if it were similar to a CPU of today!

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5686401/

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