LK-99 isn’t a superconductor

> were responsible for the sharp drops in electrical resistivity and partial levitation over a magnet

Are these properties still useful? If something can levitate without being a superconductor it is already useful for a LOT of things.

> Most PhDs are incredibly specific and don’t necessary indicate broad knowledge of a field as a whole

> Which is why you should be wary of “experts” making overly broad claims about topics within their field but far outside their area of expertise.

I mostly agree, but also I think it depends on how strong you are suggesting this and if you also acknowledge that there is high variance between domains as to the variance within the distribution of knowledge. Your last sentence is where I really disagree. There is a big difference.

But I think for the general person, there's 2 things of note: 1) just because you should be wary of an expert talking outside their niche (but inside their broader domain), doesn't mean that their opinion is equal to that of a layman. I'd still trust the mostly-expert over the non-expert any day. The true-expert is often very hard to find tbh. Look for nuance and you'll increase the likelihood of finding the expert. 2) It is easy to confuse expert talk with arrogance or pretentiousness. It is also easy to be that way when talking to a layman as the nature of those conversations will never be between peers, but more akin to a teacher and student. The two parties are not equal, but we're primed to treat any non-academic setting conversation as if we are. The experts often have serious doubts and are far more self-conscious than they appear. You just won't see that unless you're a peer and can speak the language, because experts are also specifically taught to defend their work and speak with confidence. Your hint is how they respond to critiques from other experts (but that's not easy to do accurately as there's probably a lot of nuance you aren't seeing and they are speaking a different language even if you understand all the words).

Everyone should always be skeptical though. That's for certain. But I just want to make sure we don't turn knowledge into a binary setting: expert vs idiot. There's a lot in-between and that matters a lot.

I think this kind of excitement followed up with "wasn't anything after all" is both dangerous and wrong.

When science is done badly (which arguably shouldn't be considered science), which then leads the public to have elevated expectations, only then for science to be done right and disprove and reject the original "findings", public trust in science is ever so slightly damaged.

As noted by the sibling comment, the physicists (especially those who specialized in superconductor research!) were the ones who were the most skeptical of the announcement, partially because claims of room-temperature superconductors are actually relatively common, and partially because the evidence in the paper was just atrociously bad [1].

One of the things I look forward to in an HN discussion is the comments of people who can collate expert opinions on the subject and surface these kinds of points in a more ELI15 kind of way. But despite there being ~a week of LK-99 stories permanently on the front page, there wasn't much of that (a little on the initial thread, and virtually nothing for the next several days)--and it's not for lack of physicists commenting on the topic (in other forums)!

[1] I saw someone point out that, when you translate the units on the resistivity/temperature graph, it is a worse conductor than copper at room temperature, below its claimed critical temperature.

"The science is settled."

Proceeds to quote a guy who studied chemistry at university and now works in finance.

Now, Im not saying it is a superconductor. But please, don't insult my intelligence with garbage like that, I'm more inclined to believe that kind of reporting is evidence that serious scientists are not willing to go on record as saying it isn't.