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Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

arxiv.org

91–100 of 389 posts

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#91

Earlier quoted context omitted.

> Worst case scenario, we got another class of high temp (warmer than liquid nitrogen but cold enough that applications are limited) superconductor but nothing revolutionary since at this point, it is pretty conclusive that there is something interesting with LK-99. I don't think that's the worst case scenario. The worst case scenario is that there is actually nothing interesting with LK-99, and everything we've seen…

You're right that this is the worst case scenario, but each interesting replication or semi-replication, even sloppy replication, or theoretical model erodes at that. Being perma-skeptic is as bad as being a perma-fanboy Anyways your memory is really short. Don't you remember how when it first came out (not even a week ago) everyone was hollering that it was fake? Inb4 "extraordinary claims...": there is no fundament…

> You're right that this is the worst case scenario, but each interesting replication or semi-replication, even sloppy replication, or theoretical model erodes at that.

Not really. The ur-example of the worst-case scenario is cold fusion, and as we were reminded by somebody [1] early on, is that the first replications of the Fleischmann–Pons experiment were actually successful to some degree. Those initial replications were later retracted when it was found that there was experimental error that could observe the same phenomenon, and other replication attempts were reporting outright failure instead of partial success.

> Anyways your memory is really short. Don't you remember how when it first came out (not even a week ago) everyone was hollering that it was fake?

Your memory is really short. The first thread was 8 days ago [2], over a week ago. I've just been perusing those comments quickly, and there's very few accusations of it being fake. The dominant sentiment is along the lines of "big, if true" or "please let it be true", and there's only a few top-level comments casting any shade on its plausibility. But the threads since the weekend have largely seemed to cast aside even the limited skepticism once opined.

[1] I'd love to credit them, but sorry, trying to dig out which comment out of several hundred splayed out across the various early threads was the one I remembered is more work than I can devote at the time. Edit: credit is https://news.ycombinator.com/item?id=36884183, thanks to segfaultbuserr for finding the link.

[2] https://news.ycombinator.com/item?id=36864624

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#92

I don’t understand the physics, but it feels like a truly zero resistance conductor would violate some law of thermodynamics or something. Is a superconductor truly zero impedence or just very very very low? Because I’m seeing a lot of these graphs with something like: “0.00001ohm” as the y-axis floor.

The electrons are always moving in some direction. What a superconductor does is "just" making an electron pull others with it, making a cascade effect that biases the movement permanently.

There is no work or state change, so no reason at all to conflict with the 2nd law of thermodynamics.

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#93

I don’t understand the physics, but it feels like a truly zero resistance conductor would violate some law of thermodynamics or something. Is a superconductor truly zero impedence or just very very very low? Because I’m seeing a lot of these graphs with something like: “0.00001ohm” as the y-axis floor.

[deleted]

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#94

Earlier quoted context omitted.

Why do MRIs need zero resistance vs incredibly low resistance?

I think it's a fair question. I guess the answer is "because we have superconductors, and no material with 'very small resistance' instead". Also note that while there is zero resistance you still have parasitic currents and general interaction with the rest of the environment. So no perpetual motion for us today!

Even a 'very small resistance' would likely be prohibitive. Pure silver for instance is an excellent conductor, but when you're talking about the last little bits it's orders of magnitude difference between that and a superconductor, and those orders of magnitude difference in resistance translate into orders of magnitude more current. So even a small resistance would cause your MRI machine to have a resolution so low as to be unusable.

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#95
post #38

Off-topic, but I admire the effort to translate the formula to Unicode characters in the title. It's not just a simple copy-paste from the article.

GPT-4 does it very well though. (Not saying OP used it, was just curious if that'd work.)

Prompt:

> Observation of zero resistance above 100∘ K in Pb10−xCux(PO4)6O

> convert this to a title, with the correct usage of unicode

Output:

> Observation of Zero Resistance Above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#96

Earlier quoted context omitted.

> Worst case scenario, we got another class of high temp (warmer than liquid nitrogen but cold enough that applications are limited) superconductor but nothing revolutionary since at this point, it is pretty conclusive that there is something interesting with LK-99. I don't think that's the worst case scenario. The worst case scenario is that there is actually nothing interesting with LK-99, and everything we've seen…

Personally, I think we are past the point of this being nothing. There have been multiple confirmations of at least something unexplained going on. Maybe all of them are wrong but honestly, that is more of an extraordinary claim than saying this is something interesting, just not a full on room temp superconductor.

It's not that extraordinary.

When people rush to replicate an experiment, everybody with a positive result has something to publish very quickly, and everybody with a negative result need a lot more time to be certain of it.

The kinds of results we are seeing are very hard to get by chance or due to bad experimental setup. But as a rule, we can't really differentiate a real thing from random noise in as little time as have passed.

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#97

Earlier quoted context omitted.

You're right that this is the worst case scenario, but each interesting replication or semi-replication, even sloppy replication, or theoretical model erodes at that. Being perma-skeptic is as bad as being a perma-fanboy Anyways your memory is really short. Don't you remember how when it first came out (not even a week ago) everyone was hollering that it was fake? Inb4 "extraordinary claims...": there is no fundament…

> You're right that this is the worst case scenario, but each interesting replication or semi-replication, even sloppy replication, or theoretical model erodes at that. Not really. The ur-example of the worst-case scenario is cold fusion, and as we were reminded by somebody [1] early on, is that the first replications of the Fleischmann–Pons experiment were actually successful to some degree. Those initial replicatio…

> I'd love to credit them, but sorry, trying to dig out which comment out of several hundred splayed out across the various early threads was the one I remembered is more work than I can devote at the time.

It was posted by curiousObject at [1]. I upvoted that thread and participated in that discussion (including adding extra information on why cold fusion experiments were inherently problematic), so I have the link.

As the submitter of the current paper, I'm cautiously optimistic based on the recent theoretical and experimental results. But I strongly agree with you that a repetition of cold fusion's initial false-positive replication "success" is a real risk.

[1] https://news.ycombinator.com/item?id=36884183

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#99
post #38

Off-topic, but I admire the effort to translate the formula to Unicode characters in the title. It's not just a simple copy-paste from the article.

GPT-4 does it very well though. (Not saying OP used it, was just curious if that'd work.) Prompt: > Observation of zero resistance above 100∘ K in Pb10−xCux(PO4)6O > convert this to a title, with the correct usage of unicode Output: > Observation of Zero Resistance Above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

Wow, I would've never thought to use ChatGPT for this. Very cool.

Re: Observation of zero resistance above 100 K in Pb₁₀₋ₓCuₓ(PO₄)₆O

#100
post #38

Off-topic, but I admire the effort to translate the formula to Unicode characters in the title. It's not just a simple copy-paste from the article.

The submitter also fixed the incorrect use of the degree symbol before K, lol.

"degrees Kelvin" is wrong? Why's that?
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