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

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

#151

Post by scheme271 »

superposeur wrote: post #66

Question for the cognoscenti: supposing that LK-99 superconducts with T_c = 110 K, how significant a discovery would this be? I.e., does it establish a brand new class of high-T superconductors, or is it merely one unremarkable member of a known class? Further, does it offer advantages over other high-T superconductors such as ease of fabrication or cost?

To add to the other reply, it'd be a new class especially since it would be at standard pressure. I think the current highest Tc SC at standard pressure is at much lower temperatures. Frankly, there's probably a lot that you can do with a superconductor that you can cool with liquid nitrogen even if it can't carry much current or handle high magnetic fields. Moving from liquid helium cooling to liquid nitrogen alone significantly reduces the cost and complexity of your cooling system.

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

#152

Post by scythe »

Waterluvian wrote: post #59
ramraj07 wrote: post #55

Earlier quoted context omitted.

MRI machines work using superconducting magnets as does the LHC. So you better believe it buddy.

Why do MRIs need zero resistance vs incredibly low resistance?

The current is ridiculously large and would lead to an unacceptably high power consumption and thermal expansion with the resistivity of even a good metal (copper).

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

#153

Post by wahern »

nwiswell wrote: post #132
Analemma_ wrote: post #125

Earlier quoted context omitted.

I understand why a lot of people think this, but I don't think we can say that with confidence yet. Cold fusion "replicated successfully" multiple times in the 80s too.

There are now several authentic videos of bits of rock (lead apatite) appearing to do things around magnets that they have no business doing. Maybe there's a lot of smoke and no fire, but there's videographic evidence of something weird going on.

Unfortunately, we live in the age of TikTok. Videos on their own bring no more credibility than written text; they no longer evince a substantively greater investment of resources. I'm more inclined toward the cheerleading section of the LK-99 audience, but watching the videos I realized now is a perfect opportunity to apply recalibrated B.S. detectors.

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

#154

Post by FrustratedMonky »

Analemma_ wrote: post #125
tomohelix wrote: post #89

Earlier quoted context omitted.

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.

I understand why a lot of people think this, but I don't think we can say that with confidence yet. Cold fusion "replicated successfully" multiple times in the 80s too.

Wasn't the problem with Cold Fusion that it did NOT replicate, and thus got sullied with a bad reputation, so nobody wanted to touch it.

Then decades later, it's still kind of open question. Aren't there some studies still going on, more on the down-low since it has such a bad reputation. Kind of like the super-conductor, have to keep it quiet and make really sure before publishing.

Sabine did video on Cold Fusion that was pretty interesting. https://www.youtube.com/watch?v=ZbzcYQVrTxQ

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

#155

Post by adrian_b »

tomohelix wrote: post #30

Summary of events so far: The claim: Room temp (~300K) superconductor exists and we got it! The replication attempts: The production method is so poorly documented only a fraction of the samples being made shows any interesting properties. And among those interesting ones, results varies. Very few, if any, attempt actually completely shows the entire spectrum of properties and behaviors of a true superconductor at ro…

While the production method of the original Korean authors is poorly documented, the synthesis method used for this paper is described in a very detailed way, also mentioning a few alternative steps that have been tried, but which caused failures in obtaining the desired structure.

While their synthesis method works very well for something improvised in a couple of days, it requires significant improvements, because the samples are very inhomogeneous, which greatly complicates the measurements and the interpretation of the results.

I believe that the properties of this material will not be completely elucidated until someone grows a monocrystal of it, but developing a process for this might take months, if not years.

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

#156

Post by Klaus23 »

jcranmer wrote: post #47

Looking at the key temperature-resistivity graphs, this feels like the data doesn't support the conclusion that there's a superconductor here. The temperature-resistivity graphs of superconductors I've seen all have a fairly steep cutoff--a sharp, vertical line at critical temperature. The log-scale here complicates my intuition, but what I see is a gradual transition into noise range. Also, the graphs I've seen have…

The gradual drop could be the result of a mixed sample where different parts of the material show superconductivity at different temperatures. As more of the sample becomes superconducting, the resistance will gradually decrease until a superconducting path is created between the probes and the resistance reaches zero.

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

#157

Post by jseip »

marcosdumay wrote: post #96
tomohelix wrote: post #89

Earlier quoted context omitted.

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 a…

"It's not that extraordinary."

How is that possibly true? LK-99 is already amongst the highest-temperature superconductors ever found (with that claim substantiated by at least two independent research teams as of this moment).

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

#158

Post by FrustratedMonky »

declan_roberts wrote: post #139
progrus wrote: post #124

It’s real, it works, the Navy has a linked patent from 2017. The UFOs are a PSYOP.

The Navy does have a patent for a “lead zirconate titanate” super conductor which does sound awfully similar to what’s described in LK-99. https://phys.org/news/2019-02-navy-patent-room-temperature-s...

Man. I hope it isn't. That would be sad, all this was happening, and nobody had found the old study. Surely not.

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

#159

Post by jjallen »

tomohelix wrote: post #30

Summary of events so far: The claim: Room temp (~300K) superconductor exists and we got it! The replication attempts: The production method is so poorly documented only a fraction of the samples being made shows any interesting properties. And among those interesting ones, results varies. Very few, if any, attempt actually completely shows the entire spectrum of properties and behaviors of a true superconductor at ro…

What is this supposed to be a summary of? The temperature at which this team observed zero resistivity was much much colder than room temp.

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

#160

Post by CamperBob2 »

jacquesm wrote: post #67
throwawaylinux wrote: post #64

Earlier quoted context omitted.

> Probably a lab that confirms any piece of it will get a significant share of attention and acclaim. Why is that though? They're taking a discovery that somebody else came up with, and (mostly) follow a recipe they're given. I mean if they were synthesizing a theorized substance or significantly improving its production, or measuring an effect that was previously undetectable by known instruments and experiments the…

In science the fights are so fierce because the stakes are so small...

Typically a valid comment in academia at large, but not when high-temperature superconductors are the subject of the fight. If these claims pan out, these guys may be the next Andy Viterbi or Ray Stata.
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