Fleischmann-Pons experiment

Fleischmann-Pons experiment is an experiment that Martin Fleischmann, then one of the world's leading electrochemists, and Stanley Pons announced in 1989 that they had produced anomalous heat ("excess heat") of a magnitude they asserted would defy explanation except in terms of nuclear processes. Fleischmann and Pons further reported measuring small amounts of nuclear reaction byproducts, including neutrons and tritium. The small tabletop experiment involved electrolysis of heavy water on the surface of a palladium (Pd) electrode.
The reported results received wide media attention as "cold fusion", Many scientists tried to replicate the experiment with the few details available, some to prove it wrong, and some because they wanted to be part of this new exciting discovery. Hopes fell with the big number of negative replications, the withdrawal of many positive replications, the discovery of flaws and sources of experimental error in the original experiment, and finally the discovery that Fleischmann and Pons had not actually detected nuclear reaction byproducts.
By late 1989, most scientists considered their cold fusion claims dead, but the research was never fully abandoned, the experiment subsequently gained a reputation as pathological science.
Events preceding announcement
::See also: Cold fusion Before the Fleischmann-Pons experiment
Martin Fleischmann of the University of Southampton and Stanley Pons of the University of Utah hypothesized that the high compression ratio and mobility of deuterium that could be achieved within palladium metal using electrolysis might result in nuclear fusion. To investigate, they conducted electrolysis experiments using a palladium cathode and heavy water within a calorimeter, an insulated vessel designed to measure process heat. Current was applied continuously for many weeks, with the heavy water being renewed at intervals. For most of the time, the power input to the cell was equal to the calculated power leaving the cell within measurement accuracy, and the cell temperature was stable at around 30 °C. But then, at some point (in some of the experiments), the temperature rose suddenly to about 50 °C without changes in the input power. These high temperature phases would last for two days or more and would repeat several times in any given experiment once they had occurred. The calculated power leaving the cell was significantly higher than the input power during these high temperature phases. Eventually the high temperature phases would no longer occur within a particular cell. The grant proposal was turned over for peer review, and one of the reviewers was Steven E. Jones of Brigham Young University.
Announcement
In mid-March 1989, both research teams were ready to publish their findings, and Fleischmann and Jones had agreed to meet at an airport on March 24 to send their papers to Nature via FedEx. broke their apparent agreement, submitting their paper to the Journal of Electroanalytical Chemistry on March 11, and disclosing their work via a press release and press conference on March 23. The 1986 discovery of high-temperature superconductivity had caused the scientific community to be more open to revelations of unexpected scientific results that could have huge economic repercussions and that could be replicated reliably even if they had not been predicted by established conjecture. Cold fusion was proposing the counterintuitive idea that a nuclear reaction could be caused to occur inside a chemically bound crystal structure. Many scientists were reminded of the Mössbauer effect, a process involving nuclear transitions in a solid. Its discovery 30 years earlier had also been unexpected, though it was quickly replicated and explained within the existing physics framework.
The announcement of a new clean source of energy came at a crucial time: everyone still remembered the 1973 oil crisis and the problems caused by oil dependence, anthropogenic global warming was starting to become notorious, the anti-nuclear movement was labeling nuclear power plants as dangerous and getting them closed, people had in mind the consequences of strip mining, acid rain and the greenhouse effect, and, to top it all, the happened the day after the announcement. In the press conference, Peterson, Fleischmann and Pons, backed by the solidity of their scientific credentials, repeatedly assured the journalists that cold fusion would solve all of these problems, and would provide a limitless inexhaustible source of clean energy, using only seawater as fuel. They said the results had been confirmed dozens of times and they had no doubts about them. In the accompanying press release Fleischmann was quoted saying: "What we have done is to open the door of a new research area, our indications are that the discovery will be relatively easy to make into a usable technology for generating heat and power, but continued work is needed, first, to further understand the science and secondly, to determine its value to energy economics." although this paper was later accepted for publication by the journal Fusion Technology. Nathan Lewis, professor of Chemistry at the California Institute of Technology, led one of the most ambitious validation efforts, trying many variations on the experiment without success, while CERN physicist Douglas R. O. Morrison said that "essentially all" attempts in Western Europe had failed. On April 10, 1989, a group at Texas A&M University published results of excess heat and later that day a group at the Georgia Institute of Technology announced neutron production—the strongest replication announced up to that point due to the detection of neutrons and the reputation of the lab. In 12 April Pons was acclaimed at a ACS meeting. Another attempt at independent replication, headed by Robert Huggins at Stanford University, which also reported early success with a light water control, saved cold fusion almost single-handedly and became the only scientific support for cold fusion in the 26 April US Congress hearings. But, when he finally presented his results, he reported an excess heat of only one celsius degree, a result that could be explained by chemical differences between heavy and light water in the presence of lithium, and his research was derided by scientists who saw it later. For the next six weeks, competing claims, counterclaims, and suggested explanations kept what was referred to as "cold fusion" or "fusion confusion" in the news.
In April 1989, Fleischmann and Pons published a "preliminary note" in the Journal of Electroanalytical Chemistry. Fleischmann and Pons replied to this critique, but the only thing left clear was that no gamma ray had been registered and that Fleischmann refused to recognize any mistakes in the data. A much longer paper published a year later went into details of calorimetry but did not include any nuclear measurements.
On May 1, 1989, the American Physical Society held a session on cold fusion in Baltimore, including many reports of experiments that failed to produce evidence of cold fusion. At the end of the session, eight of the nine leading speakers stated that they considered the initial Fleischmann and Pons claim dead with the ninth, Johann Rafelski, abstaining. Steven E. Koonin of Caltech called the Utah report a result of "the incompetence and delusion of Pons and Fleischmann" which was met with a standing ovation. Douglas R. O. Morrison, a physicist representing CERN, was the first to call the episode an example of pathological science.
On May 4, due to all this new criticism, the meetings with various representatives from Washington were cancelled.
From May 8 only the A&M tritium results kept cold fusion afloat.
In July and November 1989, Nature published papers critical of cold fusion claims. Negative results were also published in several other scientific journals including Science, Physical Review Letters, and Physical Review C (nuclear physics).
The United States Department of Energy organized a special panel to review cold fusion theory and research. The panel issued its report in November 1989, concluding that results as of that date did not present convincing evidence that useful sources of energy would result from the phenomena attributed to cold fusion. By this point, however, academic consensus had moved decidedly toward labeling cold fusion as a kind of "pathological science".
In early May 1990 one of the two A&M researchers, Kevin Wolf, acknowledged the possibility of spiking, but said that the most likely explanation was tritium contamination in the palladium electrodes or simply contamination due to sloppy work. In June 1990 an article in Science by science writer Gary Taubes destroyed the public credibility of the A&M tritium results when it accused its group leader John Bockris and one of his graduate students of spiking the cells with tritium. In October 1990 Wolf finally said that the results were explained by tritium contamination in the rods. A A&M cold fusion review panel found that the tritium evidence was not convincing and that, while they couldn't rule out spiking, contamination and measurements problems were more likely explanations. and Bockris never got support from his faculty to resume his research.
In March 1990 Dr. Michael H. Salamon, a Utah physicist, and nine co-authors reported negative results. University faculty were then "stunned" when a lawyer representing Pons and Fleischmann demanded the Salamon paper be retracted under threat of a lawsuit. The lawyer later apologized; Fleischmann defended the threat as a legitimate reaction to alleged bias displayed by cold-fusion critics.
In 30 June 1991 the National Cold Fusion Institute closed after it ran out of funds; it found no excess heat, and its reports of tritium production were met with indifference.
In 1 January 1991, Pons left his tenure, and both he and Fleischmann quietly left the United States. In 1992 they resumed research with Toyota Motor Corporation's IMRA lab in France. The IMRA laboratory was closed in 1998 after spending £12 million on cold fusion work.
Pons has made no public declarations since, and only Fleischmann continues giving talks and publishing papers. and critical of cold fusion research methods and the conduct of cold fusion researchers. The scientific community continues to maintain a skeptical view on the subject due to the lack of experimental reproducibility and theoretical implausibility. New experimental claims are routinely dismissed.

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