Another example of this was Millikan's determination of the fundamental electric charge (of one electron). The first, famous experiment had a major error; and subsequently everyone who independently replicated the experiment, for two decades, came up with the same error, in the same direction. The people whose experiments got the correct value probably self-selected themselves out of publishing it.

https://en.wikipedia.org/wiki/Oil_drop_experiment?useskin=ve... ("Millikan's experiment as an example of psychological effects in scientific methodology")

Room-temperature superconductors have so many urgent commercial uses that if this fake, I doubt the error will persist for that long. There's too much at stake.

There's also probably a hundred labs skipping over replication completely to try and beat someone else out on a random permutation of these materials and methods and hoping to get lucky.

Yes, "replication" in this experiments usualy means foloeing the oficial recipe and many small variants.

Publishing an exact reproduction is difficult, but a new record a few degrees hotter is easy. (And even another variant with a lower temperature and more tolerance for current or magnetic field can be published with the right text.)

> but a new record a few degrees hotter is easy

Assuming one exists. Assuming it is real.

Yep. Easier to publish, assuming it exist and you can find it.

I can't see why they'd skip replication given the uncertain status of the original process. They'd try to replicate as closely as possible, confirm they have a superconducting material, then they'd branch out from their established process. Starting from a variation means they don't know whether it doesn't work because of the variation or because it doesn't work at all.

I hear some very clever labs can do more than one thing at a time.

That’s not unreasonable, but the high-risk, high-reward approach would be to let researchers elsewhere do basic verification, while you try to leap a step ahead of them by going directly to derivative variations.

Abandon the work if nobody can replicate LK-99 within a few weeks and you haven’t really lost out badly.

Boiling-water-temperature superconductors. Pinch me, it feels like a dream.

It is interesting to note that while the error was in the same direction, the magnitude of the error decreased in subsequent studies. No one expects to get exactly the same result, so there was room for variation towards the true result.

I remember being interested enough to suspend disbelief for a little while with rossi's e-cat:

https://en.wikipedia.org/wiki/Energy_Catalyzer

nothing happened, of course, but the idea of an elegant energy source was so seductive.

The experiments with the e-cat were measuring temperatures and estimating heat flow of the hot air flowing arround the device. That's too difficult to do acurately.

If you see a report of a groundbreaking experiment that only measure the heat of the air, you can safely press the "meh" button.

Why did those early experimenters report positive reports? Did they inadvertently do something wrong themselves that looked like cold fusion?

> Did they inadvertently do something wrong themselves that looked like cold fusion?

Yes, probably

This blog talks about some of the many pitfalls that could mislead researchers: https://coldfusionblog.net/2019/03/13/the-case-against-cold-...

Some of the errors are very subtle. It’s not surprising that mistakes were made

It was a great blog, it was a lot of fun when I found it.

The summary was basically that, designing a reliable calorimetry equipment and experiment suitable for use in Fleischmann-like experiments is just uniquely challenging, it remained an unsolved problem even decades after the initial fiasco. The whole experiment setup is inherently error-prone. I found it was pretty interesting.

One researcher P.J. King who recently attempted a replication [1] commented online [2] that:

> We observed the claimed heat effect, both in magnitude and duration, in our parallel __control__ cells. This indicates a calibration error in the apparatus. One little known fact about these electro-chemical cell experiments is that they are run for a week or more before the effect is observed. Typically, calibration is conducted over a few hours and is done both before an experimental run and intermittently during it, to re-check thermal stability.

> We submit that this approach to calibration is inadequate for establishing a calorimeter’s propensity for heat artifacts. Stability over time periods longer than the experiment should be demonstrated in order to minimize the possibility of misinterpreting the fluctuations that we observed as “excess heat” events.

> Consequently, we contend that all claims of anomalous heat in LENR experiments using electro-chemical cells that do not exhibit thermal stability on a time period longer than the time duration of the experiment itself must be thrown out. As the majority of research over the past 30 years has not demonstrated this kind of calibration stability, that eliminates most of the effort in this field. You can read more about our work on the ReResearch LLC website.

> That is not to say that we know everything about hot fusion in the solid state or how quantum mechanical interactions might impact fusion reactivity. There is much still to be discovered. But these electro-chemical LENR heat experiments are noise, not signal.

[1] Guffey, Mason J., Yang Tang, and P.J. King. 2016. “Attempted Replication of Excess Heat in the Letts Dual-Laser Experiment.” Journal of Condensed Matter Nuclear Science 20 (1): 1–28.

[2] https://www.youtube.com/watch?v=ZbzcYQVrTxQ&lc=UgzFM3zS0QyP5...

Small effect sizes make it easy to confuse noise for positive results. Throw into it the very strong desire to see the thing work, and, well, even the best of us are only human.

IIRC, there were two groups of groups working on it (the process was simple enough that a description from the press conference was enough to get started):

* people looking for fusion neutrons, who did not have much experience with the finickiness of neutron detectors and who reported seeing them when they were getting experimental errors, and

* people looking for excess heat, which was simply inherently difficult to measure accurately.

On the other hand, there wasn't a publication delay for the negative reports; within a week the groups started talking to each other and realized they weren't unique in not finding anything.

Gary Taubes's Bad Science: The Short Life and Weird Times of Cold Fusion is pretty good.

I miss Cold Fusion. What a wonderful idea. It's a shame reality didn't cooperate.

The guys at Falcon Space said they were working on trying to reproduce it today - they said they have everything they need. This is their channel https://www.youtube.com/@FalconSpace where you can learn more about them