121–130 of 389 posts
So exciting! Just FYI, the wikipedia page for LK-99 has a very useful tracking grid of replication attempts with sources: https://en.wikipedia.org/wiki/LK-99
We'll probably know for sure within the month!
This is so reminiscent of what happened after Fleischmann & Pons. Labs attempting to replicate saw this property, or that property, but never the whole, unequivocal picture. Here we have a room temperature superconductor that isn't a superconductor at room temperature. A sample that has no measured Meissner Effect at any temperature. And the authors admit that some (many?) of the samples tested out as semiconductors.…
You know, because hype.
This is, as the kids say, very bullish.
I'm very much conservative about this paper because while the graph in Fig. 3a says $T_c^{zero}$ being 110 K, the "zero" resistance is actually only 1e-5 Ω (!) and even if the sample is possibly superconducting its critical temperature would be much lower than 110 K anyway. I'm aware of the difficulty in obtaining larger samples, but the label in that graph is really misleading regardless.
Well, it's at a 1mA test current (I'm assuming a 4 point probe to mitigate contact resistance) so 10u Ohm would give a 10nV DC signal. That's a pretty small voltage signal and comparable to a fairly standard chopper stabilized instrumentation amp rms noise at room temp near DC. I'm not sure whether higher currents are all that reasonable. Cooling the precision amp is an option to reduce the noise figure, but at that…
The UFOs are a PSYOP.
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.
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…
Some literature suggests its a "one dimensiononal" superconductor only kinda works in tiny monocrystaline grains. ...But maybe thats even more interesting for, say, microelectronics? Especially if the resistance orthogonal to the superconductivity is high, if such a thing is even possible?
If you'd like to create one yourself, take a bunch of parallel insulated wires. Conductivity will be low along the wires, and high perpendicular to them.
Or alternated high-resistivity and low-resistivity sheets. Conduction will be low parallel to the sheets, and high going through them.
Lots of things behave like that.
Earlier quoted context omitted.
Well, it's at a 1mA test current (I'm assuming a 4 point probe to mitigate contact resistance) so 10u Ohm would give a 10nV DC signal. That's a pretty small voltage signal and comparable to a fairly standard chopper stabilized instrumentation amp rms noise at room temp near DC. I'm not sure whether higher currents are all that reasonable. Cooling the precision amp is an option to reduce the noise figure, but at that…
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I assume you know what that means. Even today low frequency nV signals are still hard. Did you know you can do zero-bias tunneling sensing?
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…
> 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…
well while we're one-upping each other I'm pretty sure the worst case scenario is some lk99 synthesizer actually creates a black hole which gobbles up the planet.
Earlier quoted context omitted.
Not an answer, but if you think superconductor is weird, look up superfluid, now that's going to make your head spin.
Thanks for the interesting new thing. If they suffer no loss in kinetic energy and a wave can move forever, could we use a circular pool of superfluid as an an energy storage mechanism?
Earlier quoted context omitted.
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 lo…