Maybe Nature got tired of getting burned by high-temperature semiconductors. I’m not sure this
LK-99’s purported superconductivity drew immediate scrutiny from scientists. “My first impression was ‘no.’” says Inna Vishik, a condensed matter experimentalist at the University of California, Davis. “These ‘Unidentified Superconducting Objects’, as they’re sometimes called, reliably show up on the arXiv. There’s a new one every year or so.”
is a fair representation of Vishik’s views. She seems more open to the possibility in the thread below.
Superconductor or not, LK99 came out of left field. But one can say the same about the last three discoveries of high temperature superconductivity. Prior to the 1980s, superconductivity was mostly found in metals and intermetallic compounds, with Tc maxing out around 20K.
That’s what the physicists said, while at the same time working furiously to replicate it. There were successful replications and failed replications. P&F were ridiculed, just like Kim et al. The parallel to this point is pretty close. The difference is SC is high interest in mainstream science, so whatever happens here, the search for more high temperature materials will go on. CF almost got buried it, but not quite. Not that I expect a resolution any time soon, but it’s still undecided. Ask DARPA and NASA.
Of course scientist tried to reproduce cold fusion or tried to prove it is bullshit. That is what scientist do. Same with this super conductor. It was not cold fusion though and was definitely not something that is capable of producing energy. What really happened might still not be fully explained but scientist moved on to other things.
Pons and Fleischmann were electrochemists doing an electrochemical experiment. Electrochemistry is hard. Not surprisingly, of the scientists who tried to reproduce the experiment, the ones who succeeded tended to be electrochemists. Physicists mostly failed. Why? Maybe because they didn’t have the skills, they had made up their minds ahead of time, and/or they had conflicts of interest.
The physicists moved on to other things. Here is physicist Steven Koonin, coming to his famous CF is bullshit conclusion:
You know what Koonin moved on to? Climate denial.
Some scientists continued working on CF and have been joined by younger people. I don’t know how you come to such a strong claim as this
It was not cold fusion though and was definitely not something that is capable of producing energy.
but there are more than a few people who disagree.
Even Rons and Fleischmann didn’t actually show fusion. Fusion requires the detection of tritium which nobody ever showed to be produced. Maybe something happened. Maybe it even produced some excess energy. But It wasn’t fusion. Not being able to reliably reproduce it for more than 30 years now and it going against everything we know about particle physics makes me very comfortable saying it doesn’t exist.
Even Rons and Fleischmann didn’t actually show fusion.
Fleischmann later said it was a mistake to call it fusion. And most people working on it now refer to it as LENR (Low Energy Nuclear Reaction). I call it cold fusion because most people will immediately know what I mean. If you want to say it’s not fusion, that’s fine. I obviously can’t say for sure.
Fusion requires the detection of tritium
Not true. Tritium is produced in a hot fusion D-D reaction about half the time. There’s no fundamental reason the branching ratio couldn’t be different in other circumstances. In that case tritium production could be decreased, and possibly go undetected.
which nobody ever showed to be produced.
Not true. Pons and Fleischmann claimed tritium production in their original paper. Maybe you mean to say it is disputed. But it was also subsequently found by a number of others. So maybe you can fall back to saying it hasn’t been reliably reproduced. Fine.
Maybe something happened. Maybe it even produced some excess energy.
There are hundreds of published papers spanning the 34 years since P&F’s announcement saying just that.
it going against everything we know about particle physics makes me very comfortable saying it doesn’t exist.
I don’t know who we is. Edward Teller didn’t think this. Julian Schwinger didn’t either. Brian Josephson is still around and he doesn’t agree with you. You’re entitled to your opinion but maybe you shouldn’t be quite so comfortable.
As a layperson, I’m trying to understand if the concept of cold fusion just hasn’t been proven, or if it’s actually considered a physical impossibility by most physicists.
One of the many weird aspects of this topic is that “cold fusion” isn’t even a remotely controversial phenomenon. It exists and has been known for a long time. What P&F claimed is a different matter. That was and remains controversial.
I have no expectation whatsoever of convincing anyone that CF is real or that it is worth studying. Occasionally, people do come around on their own. Rob Duncan is an example:
Duncan was asked by CBS NewsSixty Minutes to investigate cold fusion on their behalf, and his findings were reported on the program in April, 2009.[5] In this program he said that he had abandoned his doubts and was now convinced of the possibilities of cold fusion. He also gave a speech at The Missouri Energy Summit about his findings and on the scientific method.[6]
As for whether most physicists consider it impossible, idk for sure but I would guess that if you asked, the most common reflex would be to say that it is a crackpot idea or something equivalent. But in response, I think what Arthur C. Clarke said is apt: “If an elderly but distinguished scientist says that something is possible, he is almost certainly right; but if he says that it is impossible, he is very probably wrong.”
If you have some interest, you could watch Sabine’s video below. She’s generally skeptical but not dismissive.
Very possible, the world is spending an enormous amount of money looking into it. What Fleishman and Pons were doing is almost certainly not how to go about it.
It’s as close to official as we’ll probably get: LK-99 is likely simply a ferromagnetic material, which explains its levitating properties, according to new research from Peking University.
The room temperature superconductivity revolution will have to wait another day.
Hey I got a dumb question: why don’t they just put some probes down and measure the resistance? The floaty stuff is cool but I really wanna see them hook up a picoammeter and see it say zero.
I don’t know the details of how they’re actually doing the measurments but I picture a sample cooled to low temperature then placed on the stage of a 4-point probe (which is what the Kim paper says was used to measure resistivity). You could do a sequence of measurements as the sample warms up while you simultaneously measure the sample temperature with a thermocouple.
I looked into this. According to Edmund Storms, in 2012, total worldwide historical investments had reached about $500M for cold fusion and $25B for hot fusion. More recent estimates I got from Bing (which maybe isn’t entirely trustworthy) are $1.2B for cold fusion and $55B for hot. These numbers are consistent with my personal guesstimate that current annual spending on hot fusion is in the billions while cold fusion is 10s of millions.
I think the amount spent on cold fusion is barely enough to keep work going and don’t have much hope of seeing significant progress any time soon, though ofc I hope to be proven wrong.
So you are basically redefining cold fusion to not mean fusion anymore. I have no problem with the possibility of a low energy nuclear reaction. But that is not fusion. I also doubt it to be energy positive in a significant enough way to be useful as we have no theoretical explanation how it could be. Hot fusion gets all the money because we have shown fusion at high temperatures exist and is energy positive by making a bunch of bombs and we have a solid theory on how to possibly do that in a controlled way and extract enery from it.
The reason LENR get little funding is also because nobody has come up with an accepted theory on what it is and how it could be energy positive.
