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Naive question, and I hope someone more knowledgeable than me can enlighten me here; Why are we even testing for superconductivity with levitation, instead of just checking for current loss/heat loss while conducting?
Note: I'm not a physicist. Just my understanding from reading.
Naive question, and I hope someone more knowledgeable than me can enlighten me here; Why are we even testing for superconductivity with levitation, instead of just checking for current loss/heat loss while conducting?
Naive question, and I hope someone more knowledgeable than me can enlighten me here; Why are we even testing for superconductivity with levitation, instead of just checking for current loss/heat loss while conducting?
One cannot measure superconductivity with an ordinary ohmmeter. Electrodes, wires and the ohmmeter itself are resistive, the meter can never show zero ohms. You need to set an experiment up with a current source and a voltmeter to measure the IV curve across the material [1]. Even then, the voltmeter will never show "zero" volt because of noise, which needs to be minimized in the experiment and removed during post-processing. In this case, sample preparation is also problematic as the synthesized material is not uniform. And your measurement is also expected to be temperature-dependent to show the material's transition to a superconductor. It's more involved than seeing it floating on a magnet, to say the least.
[1] It's basically the same 4-wire Kelvin sensing used by all milli-ohmmeters. But to characterize superconductivity, you need to do even better. https://en.wikipedia.org/wiki/Four-terminal_sensing
Earlier quoted context omitted.
They were refusing to share them with anyone reputable until today. Today, they said they would share them, so hopefully this will all be over soon (but IMO it's already resolved).
> They were refusing to share them with anyone reputable until today. This is incorrect (under some definition of "reputable"), because KENTECH [1] has reportedly received samples from Q-Center for the analysis, which started on July (following the MOU on May) and is estimated to finish within 6 months. Whether KENTECH is reputable or not, and whether it should be considered affiliated with Q-Center is of course deba…
Naive question, and I hope someone more knowledgeable than me can enlighten me here; Why are we even testing for superconductivity with levitation, instead of just checking for current loss/heat loss while conducting?
This question has been asked with near identical or very similar wording in almost every LK-99 submission I've seen over the last week or so... Is there something botnet-y happening? I find it hard to believe anyone reading similar threads could have missed the numerous answers to this and similarly-formed questions that have been offered lately.
Naive question, and I hope someone more knowledgeable than me can enlighten me here; Why are we even testing for superconductivity with levitation, instead of just checking for current loss/heat loss while conducting?
This question has been asked with near identical or very similar wording in almost every LK-99 submission I've seen over the last week or so... Is there something botnet-y happening? I find it hard to believe anyone reading similar threads could have missed the numerous answers to this and similarly-formed questions that have been offered lately.