"The third careful Japanese experiment by Jirohta Kasagi and his colleagues at Tohoku University was designed to test this hypothesis. Deuterium ions of a variety of low energies were fired into metals that had been saturated with deuterium; the measured rates of fusion were then compared with expectations. The rates decreased steeply at low energies because of the Coulomb barrier (electrical repulsion), and no unexpected enhancement was observed of the kind that would be needed to justify Fleischmann and Pons's claims.
"It might be thought that the three Japanese results would be decisive, but the two summary speakers, Tullio Bressani of Turin and Mike McKubre of SRI International, were optimistic and belittled or ignored them and instead talked of other experiments that were not performed with the same careful controls. Some remarkable new claims were mentioned. James Patterson of Clean Energy Technologies (CETI) was scheduled to speak about his claims that tiny balls coated with metal, generally nickel, could generate energy, but he did not talk. Instead his collaborator, George Miley of the University of Illinois and editor of the journal Fusion Technology, reported that experiments using these balls produced transmutations of the nickel to many other elements even as heavy as lead; he did not worry about the origin of the extra neutrons needed to create lead.
"What was not said at ICCF-6 was also interesting. Many people who had reported a sensational first result now no longer speak of it or try to extend it. For instance, on the first day of the ICCF-3 conference in Nagoya, Nippon Telephone and Telegraph (NTT) had issued a press release saying that one of their researchers had solved cold fusion and had reproducible results. NTT promptly saw its shares rise in value by $8 billion--but within a few days, they fell back to their previous level. The experiment was widely criticized but since has neither been mentioned again nor formally withdrawn.
"There is one point on which all true believers in cold fusion agree: their results are not reproducible. To most scientists, this implies that cold fusion results are not believable, but true believers suggest that this unpredictability makes them more interesting!
"From 1992 onward, many claims were made for cold fusion using normal water instead of heavy water. It is well known that D-D (deuterium-deuterium) fusion has a much higher rate, by many orders of magnitude, than H-H (hydrogen-hydrogen) fusion. In fact, early claims of cold fusion stated that the results must be attributed to fusion because they happened only with deuterium and never with hydrogen, which indeed was used as a control. Also, from 1992 onward, claims of transmutations have been made. One of these was the old alchemists' claim of turning mercury to gold; others claimed small changes in the isotopes. Miley's claim was doubly astonishing, as his claimed transmutations used hydrogen instead of deuterium.
"If there are so many claims over so many years, some people inevitably wonder if perhaps there just might be something in them. But the cold fusion claims are mutually contradictory; if H-H fusion were to work, then D-D fusion should cause the apparatus to explode. Also, there are more experiments that find no effect than those claiming one, and these negative experiments tend to be more carefully carried out. Some claims can be rejected by other subsequent experiments: Steve Jones of Brigham Young University--originally a rival of Fleischmann and Pons who made somewhat different claims for neutron production--is now a strong opponent of cold fusion and indeed has done experiments showing that in Fleischmann and Pons's open cells, the hydrogen and oxygen gases can mingle and recombine giving out apparent excess heat. If this potential for recombination is blocked, there is no excess heat.
"With all this negative evidence, how can Fleischmann, Pons and others continue? The short answer is that true believers can always find something to encourage them, and they can ignore the rest. Cold fusion is much more persistent than previous examples of pathological science, such as polywater, which ended soon after the principal supporters gave up. Here there have been well-organized public relations campaigns.