3 ms·

This reminds me of the story behind the "discovery" of cold fusion in the 80s. Sure, Pons & Fleischman may have thought they measured something, but in the end

• tzs 11y ago
  Cold fusion is a bit more complicated than that. The early experiments were certainly flawed, and there were way to many people announcing results for publicity before they had checked their work. After a few years, it was no longer socially acceptable for respected scientists to work on cold fusion. It didn't matter anymore how good your reputation was as a researcher, or how carefully designed your experiment was--if your research was in cold fusion, it would get largely ignored. Unfortunately, this happened around the time a couple groups of respected researchers with good experiment design were getting interesting results pointing to real new phenomena, and perhaps explaining why prior results had been so erratic. David Goodstein around this time wrote a great article [1] looking back at cold fusion, which included a discussion of these later results, and how socially science had reached a state where they could not be considered. Here are the last few paragraphs. All of this was much less important than the fact that Cold Fusion experiments, if they gave positive results at all, gave them only sporadically and unpredictably. When Bednorz and Mueller announced the discovery of high-temperature superconductivity in 1986, no one carped about control experiments, because, once the recipe was known, any competent scientist could make a sample and test it and it would work immediately. If, at their press conference, Pons and Fleischmann had given a dependable recipe for producing excess heat, they very likely would be Nobel Prizewinners now (as Bednorz and Mueller are) rather than social outcasts from the community of scientists. The essential key to the return of Cold Fusion to scientific respectability is to find the missing ingredient that would make the recipe work every time. Experiments done in the U.S. and in Japan, and reported at the Maui meeting indicate that the missing ingredient may have been found. In all the various Cold Fusion experiments, the first step is to load deuterium into the body of metallic palladium. The issue is how much deuterium gets into the metal. The ratio of the number of atoms of deuterium in the metal to the number of atoms of palladium is called x. It turns out, by means of electrolysis, or by putting the metal in deuterium gas, that it is rather easy to get x up to the range of about 0.6 or 0.7. That is already a startlingly high figure. If there are almost as many deuterium atoms as palladium atoms in the material, the density of deuterium (a form of hydrogen) is essentially equal to that of liquid hydrogen rocket fuel, which can ordinarily exist only at extreme low temperatures. In other words, palladium (and certain other metals including titanium) soak up almost unbelievable amounts of hydrogen or deuterium if given the chance. This is far from a new discovery. However, according to the experiments reported at Maui, x=0.6 or 0.7 is not enough to produce Cold Fusion. Both the American and Japanese groups showed data indicating there is a sharp threshold at x=0.85. Below that value (which can only be reached with great difficulty and under favorable circumstances) excess heat is never observed. But, once x gets above that value, excess heat is essentially always observed, according to the reports presented at Maui, and recounted by Franco Scaramuzzi in his seminar at the University of Rome. The audience at Rome, certainly the senior professors who were present, listened politely, but they did not hear what Franco was saying (that much became clear from the questions that were asked at the end of the seminar, and comments that were made afterward). If they went away with any lasting impression at all, it was just the sad realization that a fine scientist like Franco had not yet given up his obsession with Cold Fusion. They cannot be blamed. Any other audience of mainstream scientists would have reacted exactly the same way. If Cold Fusion ever gains back the scientific respectability that was squandered in March and April of 1989, it will be the result of a long, difficult battle that has barely begun. Recently, I told this story in a Philosophy course we teach at Caltech called "Ethics of Research." The first question, when I finished my tale, was, do I believe in Cold Fusion? The answer is, no. Certainly, I believe quite firmly the theoretical arguments that say Cold Fusion is impossible. On the other hand, however, I believe equally firmly in the integrity and competence of Franco Scaramuzzi and his group of co-workers at Frascati. I was disturbed when I saw that Franco had gotten caught in the web of science-by-news conference in April 1989 (although I was truly pleased that he finally got the long overdue recognition his agency ENEA owed him), and I was even more distressed when I learned that Franco and his group had observed excess heat (the "bad kind" of Cold Fusion). However, I have looked at their cells, and looked at their data, and it's all pretty impressive. The Japanese experiment showing that heat nearly always results when x is greater than 0.85 looks even more impressive on paper. It seems a particularly elegant, well designed experiment, at least to the untutored eye of a physicist (what do I know about electrochemistry?) What all these experiments really need is critical examination by accomplished rivals intent on proving them wrong. That is part of the normal functioning of science. Unfortunately, in this area, science is not functioning normally. There is nobody out there listening. I suppose that, if nuclear fusion really does take place whenever x is greater than 0.85 in palladium, the world of conventional science will eventually be forced to take notice. If not, then the whole story I have told you is nothing but a curious footnote to a bizarre and ugly episode in the history of science. Either way, I think the story illuminates the inner dynamics of the scientific enterprise in a way that few other stories have done. For that reason alone, it may be worth telling. [1] http://www.its.caltech.edu/~dg/fusion_art.html http://www.its.caltech.edu/~dg/fusion_art.html
• Animats 11y ago
  That was taken very seriously at the time. I went to a well-attended talk at Stanford by a Stanford physicist who was trying to replicate the Pons/Fleischman experiment. When they first set up the apparatus, they had radiation detectors with alarms, in case it started generating a dangerous level of neutrons. After some initial tests where not much happened, they moved the radiation alarm gear back a bit. Total measured neutron output, best case, appeared to be twice background. That's small enough that people moving around (people are mostly water) was enough to cause such variation. So they moved the experiment to a "neutron cube", a big box built of lead bricks where few background neutrons penetrated. Then there was no significant difference in neutron levels between "off" and "on". They also tried heat generation measurement. Because you have to put power into the Pons/Fleischman apparatus to get anything to happen (it's not self-sustaining) it's a difficult experiment to do accurately. It requires water jackets, insulation, and lots of measurements. They were unable to detect any heat output above measurement noise.