Superconductivity fight

[shpalman]

Preprint server removes ‘inflammatory’ papers in superconductor controversy

This is about that business of high-pressure room-temperature superconductors (i.e. "we got them to work at room temperature we only need a huge pressure to do it") as opposed to normal-'pressure low-temperature superconductors (i.e. "we got them to work at normal pressure we only need a low temperature to do it"). The low temperature is probably easier but yeah, room-temperature superconductors, if you believe the results, which there are obviously some who don't.

[Grumble]

Preprint server removes ‘inflammatory’ papers in superconductor controversy

This is about that business of high-pressure room-temperature superconductors (i.e. "we got them to work at room temperature we only need a huge pressure to do it") as opposed to normal-'pressure low-temperature superconductors (i.e. "we got them to work at normal pressure we only need a low temperature to do it"). The low temperature is probably easier but yeah, room-temperature superconductors, if you believe the results, which there are obviously some who don't.

The temperature of superconductivity was a hot topic back in the 90’s when I was learning about it. Terrible straight-line extrapolation from essentially 2 groups of data points to show how it was all but inevitable that we would get room temperature superconductivity sometime soon. Motivated reasoning in abundance.

[shpalman]

Preprint server removes ‘inflammatory’ papers in superconductor controversy

This is about that business of high-pressure room-temperature superconductors (i.e. "we got them to work at room temperature we only need a huge pressure to do it") as opposed to normal-'pressure low-temperature superconductors (i.e. "we got them to work at normal pressure we only need a low temperature to do it"). The low temperature is probably easier but yeah, room-temperature superconductors, if you believe the results, which there are obviously some who don't.

The temperature of superconductivity was a hot topic back in the 90’s when I was learning about it. Terrible straight-line extrapolation from essentially 2 groups of data points to show how it was all but inevitable that we would get room temperature superconductivity sometime soon. Motivated reasoning in abundance.

Our lecturer had just written a textbook on superconductivity in which he wrote that he'd left the chapter on high-Tc until last in the hope that someone would have figured out how it worked by the time he got around to it. That was also back in the 90's.

[dyqik]

Preprint server removes ‘inflammatory’ papers in superconductor controversy

This is about that business of high-pressure room-temperature superconductors (i.e. "we got them to work at room temperature we only need a huge pressure to do it") as opposed to normal-'pressure low-temperature superconductors (i.e. "we got them to work at normal pressure we only need a low temperature to do it"). The low temperature is probably easier but yeah, room-temperature superconductors, if you believe the results, which there are obviously some who don't.

The temperature of superconductivity was a hot topic back in the 90’s when I was learning about it. Terrible straight-line extrapolation from essentially 2 groups of data points to show how it was all but inevitable that we would get room temperature superconductivity sometime soon. Motivated reasoning in abundance.

Our lecturer had just written a textbook on superconductivity in which he wrote that he'd left the chapter on high-Tc until last in the hope that someone would have figured out how it worked by the time he got around to it. That was also back in the 90's.

Really high temperature superconductivity would be fantastic for fusion power...

[shpalman]

“There is a lot of evidence for superconductivity here if you take it at face value,” said Jorge Hirsch, a physicist at the University of California, San Diego. “But I do not believe any of what these authors say. I am not sold at all.”

Evidence of near-ambient superconductivity in a N-doped lutetium hydride

Here we report evidence of superconductivity on a nitrogen-doped lutetium hydride with a maximum Tc of 294 K at 10 kbar, that is, superconductivity at room temperature and near-ambient pressures.

[Grumble]

I mean calling 10kbar “near ambient” is a very relative term. This kind of thing should be replicable so I shall reserve judgement. I hope it’s true.

[dyqik]

Given that their previous paper at even higher pressures was retracted due to major issues, I'm not paying much attention to this.

[shpalman]

More on those major issues from a freelance science writer based in New York who had no communication about this story with his father the Managing Editor of Phys. Rev. Lett..

I'm paying attention to this to see how it turns out to be faked/wrong this time... It's a much more accessible pressure but they can always claim that the other groups haven't made the material properly when they fail to replicate, while never letting anyone else have their "working" samples for spurious IP reasons.

It's a different kind of "pressure" but we regularly make samples with about 1 GPa of biaxial elastic stress in them.

[dyqik]

There's already an arxiv paper from one Chinese team showing that they failed to replicate it.

[Grumble]

Side note from this, I wonder if there’s a region of Jupiter where temperatures and pressures are in the right region to have superconducting hydrogen, and if so would we be able to detect it?

[shpalman]

There's already an arxiv paper from one Chinese team showing that they failed to replicate it.

This? Superconductivity above 70 K experimentally discovered in lutetium polyhydride

[dyqik]

There's already an arxiv paper from one Chinese team showing that they failed to replicate it.

This? Superconductivity above 70 K experimentally discovered in lutetium polyhydride

Yeah, I think so. In that they couldn't get above 71K or below 161 GPa

[jimbob]

I'm now imagining using this to carry the electricity from my cold fusion rig

[shpalman]

... we identify a notable temperature-induced resistance anomaly of structural and/or electronic origin in LuH_xN_y, which is most pronounced in the pink phase and may have been erroneously interpreted as a sign of superconducting transition...

A few tweets regarding whether Nature can be trusted anymore in reply to that tweet from the coauthor of the retracted Majorana Nature paper...

[dyqik]

... we identify a notable temperature-induced resistance anomaly of structural and/or electronic origin in LuH_xN_y, which is most pronounced in the pink phase and may have been erroneously interpreted as a sign of superconducting transition...

A few tweets regarding whether Nature can be trusted anymore in reply to that tweet from the coauthor of the retracted Majorana Nature paper...

I've never really trusted Nature. It only takes the most surprising and potentially significant results in any particular field, and passes them through an non field-expert editorial team, who have to find good reviewers for that paper. That makes the likelihood of any particular paper being shown to be wrong much higher than a boring paper in a boring field specific journal, whether that's due to malfeasance, researcher or reviewer incompetence or just bad luck.

[shpalman]

Plagiarism allegations pursue physicist behind possibly-made-up superconductivity claims

[shpalman]

Superconductive Fraud: The Sequel

[shpalman]

The First Room-Temperature Ambient-Pressure Superconductor

Of course nobody actually believes it.

[Brightonian]

The First Room-Temperature Ambient-Pressure Superconductor

Of course nobody actually believes it.

room-temperature superconductor (Tc≥400 K, 127∘C)

I think even my father would find a room temperature of > 127° a tad high. (Obviously, there's a specialist meaning of room temperature in fizziks.)

[dyqik]

The First Room-Temperature Ambient-Pressure Superconductor

Of course nobody actually believes it.

room-temperature superconductor (Tc≥400 K, 127∘C)

I think even my father would find a room temperature of > 127° a tad high. (Obviously, there's a specialist meaning of room temperature in fizziks.)

The paper claims to show superconductivity at temperatures below 400K, including ambient. Tc is the upper temperature limit for superconducting effects.

[dyqik]

The paper does include most, if not all, of the direct measurements of superconducting effects that I would expect to see in a proper discovery of a new superconducting material.

The claimed material is also the right kind of structure that might possibly show higher temperature superconductivity.

But obviously, any claim like this needs replication, either in measurements on additional samples produced by the group, or made independently.

[Brightonian]

The First Room-Temperature Ambient-Pressure Superconductor

Of course nobody actually believes it.

room-temperature superconductor (Tc≥400 K, 127∘C)

I think even my father would find a room temperature of > 127° a tad high. (Obviously, there's a specialist meaning of room temperature in fizziks.)

The paper claims to show superconductivity at temperatures below 400K, including ambient. Tc is the upper temperature limit for superconducting effects.

I see, thanks.

[dyqik]

The paper does include most, if not all, of the direct measurements of superconducting effects that I would expect to see in a proper discovery of a new superconducting material.

The claimed material is also the right kind of structure that might possibly show higher temperature superconductivity.

But obviously, any claim like this needs replication, either in measurements on additional samples produced by the group, or made independently.

But as an ambient environment superconductor, replicating measurements should be easy. That makes it difficult to imagine getting away with a grift on this, while high pressure measurements are harder to replicate.

ETA: which means it's either very interesting or a very stupid grift.

[shpalman]

The First Room-Temperature Ambient-Pressure Superconductor

Of course nobody actually believes it.

room-temperature superconductor (Tc≥400 K, 127°C)

I think even my father would find a room temperature of > 127° a tad high. (Obviously, there's a specialist meaning of room temperature in fizziks.)

What I think they mean is that they went up to 400 K and still hadn't seen the transition out of "superconductivity" which does strongly suggest to me that they're never in superconductivity in the first place.

[shpalman]

LK-99 is a gray-black color, as shown in Figure 3(b). It is the superconductor with the same color as typical superconductors.

Oh well if it's the same colour it must be a superconductor.