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Successful room temperature ambient-pressure magnetic levitation of LK-99

arxiv.org

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Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#151

Post by fsckboy »

jacquesm wrote: post #36
Daneel_ wrote: post #29

Earlier quoted context omitted.

It’s difficult to rule out external factors - a badly attached probe could also result in zero resistance for example. Showing diamagnetism is one of the least error-prone ways to demonstrate the superconductor effect. That’s my understanding anyway.

> a badly attached probe could also result in zero resistance for example No, a badly attached probe would usually show a larger resistance, not a smaller one. That's actually the easiest error to make, making improper contact with the sample. The resistance is measured indirectly using a reference current. So you'd measure a higher resistance or a break rather than zero if a probe were not attached correctly (unless…

>No, a badly attached probe would usually show a larger resistance, not a smaller one.

if the area is small, couldn't it be "badly attached" directly to the other probe?

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#152

Post by [deleted] »

jamesakirk wrote: post #31
taneq wrote: post #11

Earlier quoted context omitted.

I believe there’s no way to stably suspend an object on permanent magnetic fields, so if this is stable and doesn’t fall down then it’s hard to argue superconductivity isn’t involved.

You can stably suspend graphite pencil lead on permanent magnetic fields. E.G.: https://www.youtube.com/watch?v=yeIizmhzPQc

[deleted]

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#153

Post by FrostyFlowers »

est wrote: post #92

So far lab replication efforts are: Two from HUST: https://www.bilibili.com/video/BV14p4y1V7kS/ https://www.bilibili.com/video/BV13k4y1G7i1/ One by USTC https://www.bilibili.com/video/BV1Ex4y1X7ix/ this tiny sample can stand on its pointy side. One by Qufu Normal University https://www.zhihu.com/zvideo/1669820225079070720 One with THU background but claims a personal project https://www.bilibili.com/video/BV14z4y1s7V…

Several months ago a professor from Tsinghua University got 2 million views in bilibili.

https://www.bilibili.com/video/BV1cY4y1y7ZM

Translation of the title: If room temperature superconductivity is really repeated, I will eat shit

Then this topic became hot in bilibili. Currently the first LK-99 replication video reaches nearly 10 million views.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#154

Post by wenyuanyu »

est wrote: post #92

So far lab replication efforts are: Two from HUST: https://www.bilibili.com/video/BV14p4y1V7kS/ https://www.bilibili.com/video/BV13k4y1G7i1/ One by USTC https://www.bilibili.com/video/BV1Ex4y1X7ix/ this tiny sample can stand on its pointy side. One by Qufu Normal University https://www.zhihu.com/zvideo/1669820225079070720 One with THU background but claims a personal project https://www.bilibili.com/video/BV14z4y1s7V…

I am from China. Not surprised at all..

Young researchers in China often face intense competition and pressure. While they are generally well-funded in the short-term, even more so than their counterparts in the US or Europe, the lack of long-term career security can be challenging. They must continuously chase after every potential scientific breakthrough, like LK-99, not just out of passion or curiosity, but as a necessary step for survival in their career.

Furthermore, the system in China offers many awards, grants, and titles that are tied to age. These are not just for prestige but are critical for progressing in their career. This situation adds another layer of urgency and competition among young researchers.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#155

Post by dgoldstein0 »

chii wrote: post #142
nocoder wrote: post #139

I get the idea of superconductivity at room temperature in theory. But I don't have enough knowledge to understand in real terms, how will the world change if this is true?

For one, lossless storage of electricity.

I think you mean lossless transmission? If we can actually replace transmission lines effectively with it, unclear whether it's practical for that yet.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#156

Post by svnt »

postalrat wrote: post #134
bagels wrote: post #119

Earlier quoted context omitted.

I didn't see any references to cups or water in these papers.

If you can't answer the question then you won't ever understand how to measure zero resistance.

It's a limitation of the most basic approach to the problem (measuring resistance), but not a limitation of every approach (such as measuring current).

You can inject a current into a superconducting coil and take measurements of the resultant magnetic field as the current circles for an indefinite period of time. I'm not able to see how this approach analogizes to water in a cup.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#157

Post by ChuckMcM »

someplaceguy wrote: post #141
ChuckMcM wrote: post #129

For those experiencing this type of "black swan, but good" event for the first time, it is helpful to recognize that the human tendency to believe that all future "big events" will be dystopian downers, is statistically unsound. For a while I've kept a list of the things that could be "good" swan events, but to be fair I didn't have "room temperature superconductor on that list" :-) Other things that could happen: 1)…

It would have been more convincing if you had given real past examples rather than speculative future ones :) Although I'm pretty sure there are plenty that many people can think of, so it doesn't really detract much from your point.

Fair point, I felt most people would have their own list. Powered flight, semiconductors, commercially competitive solar cells, antibiotics, sterile procedure. Etc.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#158

Post by nomel »

WinnieRallycar wrote: post #99
roboticmind wrote: post #52

Earlier quoted context omitted.

The initial paper claimed superconductivity up until 400 K (127 °C or 260 °F), so I think if that's the case it would be able to withstand outdoor conditions just fine

Indeed, operating temperature seems to me less of a concern. Considering how difficult it‘s been to produce LK-99 so far, some skepticism on being able to manufacture the material in mass is warranted, I think. Still, exciting! I’m hopeful :)

Considering how people are making it at all, within days, with demonstrably poor instructions, seems to suggest manufacturing in mass has massive hope, once some time is given for refining the process.

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#159

Post by KRAKRISMOTT »

ChuckMcM wrote: post #129

For those experiencing this type of "black swan, but good" event for the first time, it is helpful to recognize that the human tendency to believe that all future "big events" will be dystopian downers, is statistically unsound. For a while I've kept a list of the things that could be "good" swan events, but to be fair I didn't have "room temperature superconductor on that list" :-) Other things that could happen: 1)…

Not quite related to 2) but if the superconductors research pans out, portable high field desktop sized MRIs would be in the bag. Current portable MRIs are all low field (and to a certain extent, somewhat useless).

Re: Successful room temperature ambient-pressure magnetic levitation of LK-99

#160

Post by NotYourLawyer »

dang wrote: post #123
NotYourLawyer wrote: post #63

Earlier quoted context omitted.

[flagged]

If someone else is wrong and you know more, it would be great to share some of what you know so the rest of us can learn. But please don't post unsubstantive putdowns—they just make everything worse. https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor... https://news.ycombinator.com/newsguidelines.html

Silently leaving incorrect information in place seems worse for the overall state of the thread than a quick note disputing it.
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