221–230 of 501 posts
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One of the elements used here is phosphorus (P) which is regulated by the DEA in the United States, and can't just be purchased online
> One of the elements used here is phosphorus (P) which is regulated by the DEA I would have figured ATF. What drug can you synthesize with phosphorus? (EDIT: Apparently meth [1].) [1] https://www.federalregister.gov/documents/2000/09/25/00-2455...
Researcher on reddit thinks it's probably spurious measurement artifacts, not superconductivity: > I would say they are not faking it, but instead they just don’t understand what they are looking at. Based on what measurements they are doing, as well as how they are doing them, they do not have a good understanding of the standard processes to characterise a superconductor. Also, based on their analysis/discussion, t…
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Nah. We have a reasonable understanding of fluids. It's just that the two things we say as simple explanations (the plane pushes air downwards causing an equal and opposite reaction to push the plane up; faster flow on top of the wing "sucks the plane upwards") are both only partial truths. Sometimes you get arguments between partisans for each of these two simplified explanations, but really both are bogus.
I’ve never understood how this battle could possibly persist, considering that planes can fly upside-down . The fact that Bernoulli’s Principle creates a low-pressure zone on the top of the aerofoil just gives you laminar flow at higher angles of attack. It really isn’t that mysterious, unless you insist that only a single physical law is allowed to come into play.
That's orthogonal. Planes flying upside down still have air flowing faster over the new "top" of the wing than the bottom.
Though, a common misunderstanding is that air must be taking the same "time" to go over the top and the bottom. This is not true.
You can build a pretty good mental model of flight with either simplified mechanism, but you end up underestimating performance by a fair bit.
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Here's a few from the top of my head: - A global power net. No solar power during the night? Just produce it on the other side of the planet. - A superconducting computer. Less resistance when pushing bits around = 500x less power consumption. - A Superconducting magnetic battery. Store power indefinitely with high efficiency.
Wouldn't less power loss not just mean lower power consumption, but the ability to run it at higher speeds while keeping the same cooling technology we current have?
Assuming of course it is possible to shrink the superconductor circuits down to the same size of the semiconductor counterpart.
Since it is apparently expected that the material is almost trivial to synthesize, I'm wondering why the original group hasn't tried to get an outside independent source to verify one of their samples before dropping this on the arXiv? Is there some other internal reason/pressure to release this now? Like they've tried to be in stealth mode for the two years since applying for the patent, but risks of leaks are growi…
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how does superconductivity benefit RF antennas? AFAIK loss at AC still occurs with superconductors because the dielectric loss through the materials still exists.
Search "superdirective superconducting antenna". With normal conductors the directivity of an antenna depends on how many wavelengths it spans; the summation of the currents over the effective aperture. With superconducting materials you can exploit the weirdness in current distribution to make very directional antennas that are small relative to the wavelength. It could be a game changer for making efficient directi…
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Nuclear fusion much easier, quantum computing, lossless electricity transmission, insane batteries. Dirt cheap MRIs, Basically welcome to the Jetsons. Much easier to mitigate climate change to the point where we can just deal with it.
Room temperature superconductivity does not help with quantum computing. The transmons or atoms or ions need to be cold so that they do not get "flipped", not because of the need for superconductors.
New scientist got a reply from the authors and a few other experts: https://www.newscientist.com/article/2384782-room-temperatur... >Kim has only co-authored one of the arXiv papers, while the other is authored by his colleagues at the Quantum Energy Research Centre in South Korea, some of whom also applied for a patent on LK-99 in August 2022. >Both papers present similar measurements, however Kim says that the seco…
Seems interesting that there appears to have been a patent application for LK-99 ( https://patents.google.com/patent/KR20230030188A/en?oq=WO202... ) filed two years ago in August 2021 (a year earlier than the article suggests). If true, it seems wild to sit on this kind of discovery for over two years. Update: Seems like there might be even more history given the name LK-99 apparently comes from the names of its disc…
New scientist got a reply from the authors and a few other experts: https://www.newscientist.com/article/2384782-room-temperatur... >Kim has only co-authored one of the arXiv papers, while the other is authored by his colleagues at the Quantum Energy Research Centre in South Korea, some of whom also applied for a patent on LK-99 in August 2022. >Both papers present similar measurements, however Kim says that the seco…
“Both papers present similar measurements” I’m not a physicist expert of superconductors, although I’ve followed quite closely that field since the ‘90s. But if the measurements are similar and correct and if the video of lk-99 levitating above a magnet demonstrating the Meissner effect is not fake, I don’t really have an alternative explanation to account for all of that. I guess that we’ll see what happens in the n…
edit: useful comment elsethread by macromaniac on plausibility of diamagnetic effects
Researcher on reddit thinks it's probably spurious measurement artifacts, not superconductivity: > I would say they are not faking it, but instead they just don’t understand what they are looking at. Based on what measurements they are doing, as well as how they are doing them, they do not have a good understanding of the standard processes to characterise a superconductor. Also, based on their analysis/discussion, t…
Agreed, this looks bogus. Some suspicious points: In the first paper, they claim to measure zero resistance (on a scale of microvolts), but are very careful not to show full RvT curves - in the second paper, we can still see significant changes below Tc where they include more complete curves. How can the resistance change significantly in the superconducting (zero resistance) state? We can actually see significant n…