4 ms·
Assuming everything in the video is real, the only remaining question is: what is the actual temperature of that sample? If all of this checks out, then it's a
by dmitrybrant 3y ago
Assuming everything in the video is real, the only remaining question is: what is the actual temperature of that sample?
If all of this checks out, then it's a new era.
- jiggawatts 3y agoSuch tiny samples warm up to room temperature very quickly, on the order of a few seconds. In my experience, it's not possible to make such small pieces of YBCO superconductor levitate, they warm up too fast.
- topynate 3y agoNo frost on the sample either. The only way I can think of to fake this in camera is to make the "sample" out of a strong magnet, and make the "magnet" a hollow shell concealing a chilled piece of YBCO!
- incrudible 3y agoYou would be surprised what can be achieved with bit of nylon string and an appropriate camera setup. If this is a most groundbreaking discovery, why waste all that screen resolution on the backdrop?
- anonymousiam 3y agoI believe the backdrop is there to show ambient conditions.
- wesleychen 3y agoI think because the minimum focus distance for most phone cameras is around 8 inches so they have to film kind of far away or else it will go blurry.
- Enginerrrd 3y agoIt looks convincing to my naive eyes, but how would you differentiate between this and diamagnetic levitation of something like pyrolitic graphite?
- cthalupa 3y agohttps://twitter.com/Andercot/status/1687748594563268608 https://twitter.com/Andercot/status/1687748594563268608 seems to indicate that simply diamagnetic levitation cannot create the level of stability shown in this video.
- Enginerrrd 3y agoI don't think that's right. Diamagnetic levitation is one of the ways you can get around Earshaw's theorem. Funny enough this is a quote taken directly from the wikipedia article that Andercot linked, in the "loopholes" section: >Earnshaw's theorem has no exceptions for non-moving permanent ferromagnets. However, Earnshaw's theorem does not necessarily apply to moving ferromagnets,[4] certain electromagnetic systems, pseudo-levitation and diamagnetic materials. These can thus seem to be exceptions, though in fact they exploit the constraints of the theorem. ... >Diamagnetic materials are excepted because they exhibit only repulsion against the magnetic field, whereas the theorem requires materials that have both repulsion and attraction. An example of this is the famous levitating frog (see Diamagnetism).
- cthalupa 3y agoSure enough. Which, well, makes sense, since superconductors are "perfect" diamagnets, so them being able to do it seems to necessitate that the greater class of diamagnets on the whole can too. The only examples I can find of stable non-superconductor diamagnets involved 4+ magnet arrays, though, or multipole magnets, e.g. https://phys.org/news/2014-08-diamagnetic-levitation-pyrolitic-graphite-magnet.html https://phys.org/news/2014-08-diamagnetic-levitation-pyrolit... and not dipole configurations like this video seems to show.
- sudosysgen 3y ago
- Arn_Thor 3y agoNo, the video contains no information about its conductivity.
- Arn_Thor 3y agoVindication https://arxiv.org/abs/2308.03110 https://arxiv.org/abs/2308.03110