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Brian Skinner
1/ Who wants to hear some scientific intrigue? A few weeks ago, a group of physical chemists posted a paper online announcing the observation of superconductivity at room temperature. Today I posted a comment pointing out something funny in their data.
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Brian Skinner Aug 9
Replying to @gravity_levity
2/ Room-temperature superconductivity has been a holy grail in physics for literally over 100 years. If we could find a material that was superconducting at room temperature, it would allow us to transport electrical power for free, and would revolutionize a bunch of industries.
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Brian Skinner Aug 9
Replying to @gravity_levity
3/ There is no fundamental reason (that we know) why some material couldn't be superconducting at room temperature. But after a century of trying to find such material the best superconductor still needs to be cooled to 90 Kelvin (-183 Celsius).
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Brian Skinner Aug 9
Replying to @gravity_levity
3/ So you can imagine how exciting/shocking it was to see two people claim to have found it (). This was a very surprising result, since neither of the constituent materials (gold and silver) are superconductors at any temperature.
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Brian Skinner Aug 9
Replying to @gravity_levity
5/ I think the sheer surprisingness of the result led many people to dismiss the paper right away. It seemed too good to be true. But if you started looking at the data, it all looked very good and consistent. Multiple independent measurements seemed to confirm superconductivity
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Brian Skinner Aug 9
Replying to @gravity_levity
6/ And the authors were from a reputable institution (the Indian Institute of Science in Bangalore) and the PI had a reputable academic pedigree (for whatever that's worth). So a certain subset of physicists started to get very excited.
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Brian Skinner Aug 9
Replying to @gravity_levity
7/ In the two weeks since the paper was posted, there have already been at least two follow-up papers posted online, and I'm sure that plenty others are in process. Some people (even some I know at MIT) dropped everything to start working on this problem.
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Brian Skinner Aug 9
Replying to @gravity_levity
8/ Here's where I come in. Looking through the paper one evening, I got curious as to why one of their measurements showed lots of random noise at low temperature, but very little noise at high temperature. I thought I might be able to analyze the data by digitizing the plot.
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Brian Skinner Aug 9
Replying to @gravity_levity
9/ But when I zoomed in closely on the figure, I saw something very surprising. Look closely at the green and blue data points here:
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Brian Skinner Aug 9
Replying to @gravity_levity
10/ They have the exact same pattern of random noise. The blue data points are clearly identical to the green ones; they have only been shifted downward by a constant amount.
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Brian Skinner Aug 9
Replying to @gravity_levity
11/ These are supposed to be two independent measurements, separated in time and in the value of certain parameters. An exactly duplicated pattern of noise is not something you would expect.
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Brian Skinner Aug 9
Replying to @gravity_levity
12/ In fact, the biggest fraud in modern physics was eventually caught because people found the exact same pattern of noise in a number of supposedly independent measurements. Eventually it was proved that he had fabricated dozens of papers' worth of data
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Brian Skinner Aug 9
Replying to @gravity_levity
13/ So this observation was potentially a big deal. Too big, in fact: I was completely paralyzed by the question of what to do about it. I spent the next week vacillating between feeling like I had a duty to point this out publicly and feeling like to do so would be irresponsible
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Brian Skinner Aug 9
Replying to @gravity_levity
14/ I talked, confidentially, to about a dozen experts in the field of superconductivity. I tracked down old theorists who had seen everything and prominent experimentalists and technicians who use the measuring equipment in question every day.
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Brian Skinner Aug 9
Replying to @gravity_levity
15/ In the end, the consensus was pretty clear: no one could imagine an explanation for how that pattern of duplicated noise could arise naturally. Which meant, at the least, that people thinking about the experiment needed to be aware of it.
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Brian Skinner Aug 9
Replying to @gravity_levity
16/ So I wrote a very short comment, stating only exactly what I noticed, and posted it publicly on the arXiv (the scientific server for publicly posting papers). Read it if you're curious: I promise you'll understand the point.
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Brian Skinner Aug 9
Replying to @gravity_levity
17/ I'm hoping this public comment will mark the end of this little bit of drama in my life. But I'll add to this thread later if something particularly interesting happens next. (end. for now.)
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Robert 🦃the baste god🦃 McNees Aug 9
Replying to @gravity_levity
I think you meant to post this link?
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Brian Skinner Aug 9
Replying to @mcnees
Oops. Thanks for catching that!
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Brian Skinner Aug 9
Replying to @gravity_levity
Sorry, here's the correct link:
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