Cold fusion

This article is about the Fleischmann-Pons claims. For accepted examples of fusion at temperatures below the millions of degrees Celsius required for thermonuclear fusion, see Nuclear fusion. For a specific example of an accepted mechanism for low-temperature fusion, sometimes referred to as cold fusion, see Muon-catalyzed fusion. For all other definitions, see Cold fusion (disambiguation).

Diagram of an open type calorimeter used at the New Hydrogen Energy Institute in Japan.

Cold fusion refers to a postulated nuclear fusion process of unknown mechanism offered to explain a group of disputed experimental results first reported by electrochemists Martin Fleischmann and Stanley Pons. Cold fusion research sometimes is referred to as low energy nuclear reaction (LENR) studies or condensed matter nuclear science.

Cold fusion, under this definition, was first announced on March 23, 1989 when Fleischmann and Pons reported producing nuclear fusion in a tabletop experiment involving electrolysis of heavy water on a palladium (Pd) electrode. They reported anomalous heat production ("excess heat") of a magnitude they asserted would defy explanation except in terms of nuclear processes. They further reported measuring small amounts of nuclear reaction byproducts, including neutrons and tritium. These reports raised hopes of a cheap and abundant source of energy.

Enthusiasm turned to skepticism as replication failures were weighed in view of several reasons cold fusion should not be possible, the discovery of possible sources of experimental error, and finally the discovery that Fleischmann and Pons had not actually detected nuclear reaction byproducts. By late 1989, most scientists considered cold fusion claims dead, and cold fusion subsequently gained a reputation as pathological science. However, some researchers continue to investigate cold fusion.

In 1989, the majority of a review panel organized by the US Department of Energy (DOE) found that the evidence for the discovery of a new nuclear process was not persuasive. There have been few mainstream reviews of the field since 1990. A second DOE review, convened in 2004 to look at new research, reached conclusions similar to the first, but with a smaller majority.

History

Early work

The ability of palladium to absorb hydrogen was recognized as early as the nineteenth century by Thomas Graham. In the late nineteen-twenties, two Austrian born scientists, Friedrich Paneth and Kurt Peters, originally reported the transformation of hydrogen into helium by spontaneous nuclear catalysis when hydrogen was absorbed by finely divided palladium at room temperature. However, the authors later retracted that report, acknowledging that the helium they measured was due to background from the air.

In 1927, Swedish scientist J. Tandberg stated that he had fused hydrogen into helium in an electrolytic cell with palladium electrodes. On the basis of his work, he applied for a Swedish patent for "a method to produce helium and useful reaction energy". After deuterium was discovered in 1932, Tandberg continued his experiments with heavy water. Due to Paneth and Peters' retraction, Tandberg's patent application was eventually denied.

The term "cold fusion" was used as early as 1956 in a New York Times article about Luis W. Alvarez' work on muon-catalyzed fusion.

E. Paul Palmer of Brigham Young University also used the term "cold fusion" in 1986 in an investigation of "geo-fusion", or the possible existence of fusion in a planetary core.

Fleischmann-Pons announcement

Electrolysis cell schematic

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. Some deuterium was thought to be accumulating within the cathode, but most was allowed to bubble out of the cell, joining oxygen produced at the anode. 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 (and 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.

In 1988, Fleischmann and Pons applied to the United States Department of Energy for funding towards a larger series of experiments. Up to this point they had been funding their experiments using a small device built with $100,000 out-of-pocket. The grant proposal was turned over for peer review, and one of the reviewers was Steven E. Jones of Brigham Young University. Jones had worked for some time on muon-catalyzed fusion, a known method of inducing nuclear fusion without high temperatures, and had written an article on the topic entitled "Cold nuclear fusion" that had been published in Scientific American in July 1987. Fleischmann and Pons and co-workers met with Jones and co-workers on occasion in Utah to share research and techniques. During this time, Fleischmann and Pons described their experiments as generating considerable "excess energy", in the sense that it could not be explained by chemical reactions alone. They felt that such a discovery could bear significant commercial value and would be entitled to patent protection. Jones, however, was measuring neutron flux, which was not of commercial interest. In order to avoid problems in the future, the teams appeared to agree to simultaneously publish their results, although their accounts of their March 6 meeting differ.

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. Fleischmann and Pons, however, pressured by the University of Utah which wanted to establish priority on the discovery, broke their apparent agreement, submitting their paper to the Journal of Electroanalytical Chemistry on March 11, and disclosing their work via a press conference on March 23. Jones, upset, faxed in his paper to Nature after the press conference.

Reaction to the announcement

Fleischmann and Pons' announcement drew wide media attention. The recent discovery of high-temperature superconductivity in 1986 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 lacked a theoretical basis that explained them. Cold fusion was proposing the counter-intuitive idea that a nuclear reaction could be affected by happening inside a crystal structure, and many scientists immediately thought of the Mössbauer effect, since it was an example of this happening, and its discovery 30 years ago had also been unexpected and it had been quickly replicated and explained within the existing physics framework.

Scores of laboratories in the United States and abroad attempted to repeat the experiments. A few reported success, many others failure. Even those reporting success had difficulty reproducing Fleischmann and Pons' results. One of the more prominent reports of success came from a group at the Georgia Institute of Technology, which observed neutron production. The Georgia Tech group later retracted their announcement. Another team, headed by Robert Huggins at Stanford University also reported early success, but this too was refuted. For weeks, competing claims, counterclaims and suggested explanations kept what was referred to as "cold fusion" or "fusion confusion" in the news.

In May 1989, the American Physical Society held a session on cold fusion, at which were heard 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 they considered the initial Fleischmann and Pons claim dead.

In April 1989, Fleischmann and Pons published a "preliminary note" in the Journal of Electroanalytical Chemistry. This paper notably showed a gamma peak without its corresponding Compton edge, which indicated they had made a mistake in claiming evidence of fusion byproducts. The preliminary note was followed up a year later with a much longer paper that went into details of calorimetry but did not include any nuclear measurements.

In July and November 1989, Nature published papers critical of cold fusion claims.

Nevertheless, Fleischmann and Pons and a number of other researchers who found positive results remained convinced of their findings. In August 1989, the state of Utah invested $4.5 million to create the National Cold Fusion Institute.

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 phenomena attributed to cold fusion. The panel noted the inconsistency of reports of excess heat and the greater inconsistency of reports of nuclear reaction byproducts. Nuclear fusion of the type postulated would be inconsistent with current understanding and would require the invention of an entirely new nuclear process. The panel was against special funding for cold fusion research, but supported modest funding of "focused experiments within the general funding system."

In the ensuing years, several books came out critical of cold fusion research methods and the conduct of cold fusion researchers.

Further developments

Cold fusion claims were, and still are, considered extraordinary. In view of the theoretical issues alone, most scientists would require extraordinarily conclusive data to be convinced that cold fusion has been discovered. After the fiasco following the Pons and Fleischmann announcement, most scientists became dismissive of new experimental claims.

Nevertheless, there were positive results that kept some researchers interested and got new researchers involved. In September 1990, Fritz Will, Director of the National Cold Fusion Institute, compiled a list of 92 groups of researchers from 10 different countries that had reported excess heat, ³H, ⁴He, neutrons or other nuclear effects.

Fleischmann and Pons relocated their laboratory to France under a grant from the Toyota Motor Corporation. The laboratory, IMRA, was closed in 1998 after spending £12 million on cold fusion work.

Between 1992 and 1997, Japan's Ministry of International Trade and Industry sponsored a "New Hydrogen Energy Program" of US$20 million to research cold fusion. Announcing the end of the program in 1997, Hideo Ikegami stated "We couldn't achieve what was first claimed in terms of cold fusion." He added, "We can't find any reason to propose more money for the coming year or for the future."

In 1994, David Goodstein described cold fusion as "a pariah field, cast out by the scientific establishment. Between cold fusion and respectable science there is virtually no communication at all. Cold fusion papers are almost never published in refereed scientific journals, with the result that those works don't receive the normal critical scrutiny that science requires. On the other hand, because the Cold-Fusioners see themselves as a community under siege, there is little internal criticism. Experiments and theories tend to be accepted at face value, for fear of providing even more fuel for external critics, if anyone outside the group was bothering to listen. In these circumstances, crackpots flourish, making matters worse for those who believe that there is serious science going on here."

In some cases, cold fusion researchers contend that cold fusion research is being suppressed. They complained there was virtually no possibility of obtaining funding for cold fusion research in the United States, and no possibility of getting published. University researchers, it has been claimed, were unwilling to investigate cold fusion because they would be ridiculed by their colleagues. In a biography by Jagdish Mehra et al. it is mentioned that to the shock of most physicists, the Nobel Laureate Julian Schwinger declared himself a supporter of cold fusion and tried to publish a paper on it in Physical Review Letters; he was deeply insulted by the manner of its rejection, and was led to resign from that body in protest.

To provide a forum for researchers to share their results, the first International Conference on Cold Fusion was held in 1990. The conference, recently renamed the International Conference on Condensed Matter Nuclear Science, is held every 12 to 18 months in various countries around the world. The periodicals Fusion Facts, Cold Fusion Magazine, Infinite Energy Magazine, and New Energy Times were established in the 1990s to cover developments in cold fusion and related new energy sciences. In 2004 The International Society for Condensed Matter Nuclear Science (ISCMNS) was formed "To promote the understanding, development and application of Condensed Matter Nuclear Science for the benefit of the public."

In the 1990s, India stopped its research in cold fusion due to the lack of consensus among mainstream scientists and the US denunciation of it.

In February 2002, the U.S. Navy revealed that its researchers had been quietly studying cold fusion continually since 1989. Researchers at their Space and Naval Warfare Systems Center in San Diego, California released a two-volume report, entitled "Thermal and nuclear aspects of the Pd/D₂O system," with a plea for proper funding.

In 2004, at the request of cold fusion researchers, the DOE organized a second review of the field. These researchers were asked to present a review document of all the evidence since the 1989 review. Their review stated that the observation of excess heat has been reproduced, that it can be reproduced at will under the proper conditions, and that many of the reasons for failure to reproduce it have been discovered.

18 reviewers in total examined the written and oral testimony given by cold fusion researchers. 9 of them were picked by the DOE for their backgrounds in theoretical nuclear physics, material science, and electrochemistry, and they were given a month to peer review the report and the supplementary material. Other 9 reviewers were picked from relevant fields, they examined the peer reviews made by the other nine reviewers, and then they assisted to six presentations of one hour each, given by six different research groups.

On the question of excess heat, the reviewers' opinions ranged from "evidence of excess heat is compelling" to "there is no convincing evidence that excess power is produced when integrated over the life of an experiment". The report states the reviewers were split approximately evenly on this topic. The reviewers that didn't find the evidence compelling cited a series of issues including: measuring excess power in a short time versus measuring the total net energy of an experiment, the non-elimination of all effects that could explain excess heat, and the net excess power being so small in percentage that it could be caused by calibration of systematic effects. Most of the reviewers, from both sides of the split, said that "the effects are not repeatable, the magnitude of the effect has not increased in over a decade of work, and that many of the reported experiments were not well documented"

On the question of evidence for nuclear fusion, the report states:

Two-thirds of the reviewers...did not feel the evidence was conclusive for low energy nuclear reactions, one found the evidence convincing, and the remainder indicated they were somewhat convinced. Many reviewers noted that poor experiment design, documentation, background control and other similar issues hampered the understanding and interpretation of the results presented.

On the question of further research, the report reads:

The nearly unanimous opinion of the reviewers was that funding agencies should entertain individual, well-designed proposals for experiments that address specific scientific issues relevant to the question of whether or not there is anomalous energy production in Pd/D systems, or whether or not D-D fusion reactions occur at energies on the order of a few eV. These proposals should meet accepted scientific standards, and undergo the rigors of peer review. No reviewer recommended a focused federally funded program for low energy nuclear reactions.

The 2004 report summarized its conclusions as being similar to those of the 1989 review despite the progress being made in calorimeters. It also recommended specific areas where research could resolve the controversies in the field, and said that the field would benefit from following peer-review processes.

Thirteen papers were presented at the "Cold Fusion" session of the March 2006 American Physical Society (APS) meeting in Baltimore. In 2007, the American Chemical Society's (ACS) held an "invited symposium" on cold fusion and low-energy nuclear reactions. Cold fusion reports have been published in Naturwissenschaften, Japanese Journal of Applied Physics, European Physical Journal A, European Physical Journal C, International Journal of Hydrogen Energy, Journal of Solid State Phenomena, Journal of Electroanalytical Chemistry, and Journal of Fusion Energy.

Cold fusion researchers have described possible cold fusion mechanisms, but they have not received mainstream acceptance. Physics Today said, in 2005, that new reports of excess heat and other cold fusion effects were still no more convincing than 15 years ago. 20 years later, in 2009, cold fusion researchers complain that the flaws in the original announcement still cause the field to be marginalized and to suffer a chronic lack of funding. Frank Close claims that a problem plaguing the original announcement is still happening: results from studies are still not being independently verified, and that inexplicable phenomena encountered in the last twenty years are being labeled as "cold fusion" even if they aren't, in order to attract attention from journalists. A number of researchers keep researching and publishing in the field, working under the name of low-energy nuclear reactions, or LENR, in order to avoid the negative connotations of the "cold fusion" label.

Research in India started again in 2008 in several centers like the Bhabha Atomic Research Centre thanks to the pressure of influential Indian scientists; the National Institute of Advanced Studies has also recommended the Indian government to revive this research. The interest in cold fusion in India had been rekindled earlier that year by a demonstration in Bangalore by Japanese researcher Yoshiaki Arata.

"Triple tracks" in a CR-39 plastic radiation detector claimed as evidence for neutron emission from palladium deuteride, suggestive of a deuterium-tritium reaction

On 22–25 March 2009, the American Chemical Society held a four-day symposium on "New Energy Technology", in conjunction with the 20th anniversary of the announcement of cold fusion. At the conference, researchers with the U.S. Navy's Space and Naval Warfare Systems Center (SPAWAR) reported detection of energetic neutrons in a standard cold fusion cell design using CR-39, a result previously published in Die Naturwissenschaften. Neutrons are indicative of nuclear reactions.

Patents

Although the details have not surfaced, it appears that the University of Utah forced the Fleischmann and Pons announcement in 23 March 1989 in order to establish priority over the discovery and its patents before the joint publication with Jones. The Massachusetts Institute of Technology (MIT) announced in April 12, 1989 that it had applied for its own patents based on the theoretical work of one of it own researchers, Peter L. Hagelstein, who had been sending papers to journals from the 5th to the 12th of April.

The U.S. Patent and Trademark Office (USPTO) now rejects patents claiming cold fusion. Esther Kepplinger, the deputy commissioner of patents in 2004, said that this was done using the same argument as with perpetual motion machines: that they do not work. Patent applications are required to show that the invention is "useful", and this utility is dependent upon the invention's ability to function. In general rejections by the USPTO on the sole grounds of the invention being "inoperative" are rare, since such rejections need to demonstrate "proof of total incapacity", and cases where those rejections are upheld in a Federal Court are even rarer: nevertheless, in 2000, a rejection of a cold fusion patent was appealed in a Federal Court and it was upheld, in part on the grounds that the inventor was unable to establish the utility of the invention. Researchers can still obtain grants and patents by giving a different name to the research in order to disassociate it from cold fusion, although this strategy has had little success in the US: the very same claims that need to be patented can identify it with cold fusion, and most of these patents cannot avoid mentioning Fleischmann and Pons' research due to legal constraints, thus alerting the patent reviewer that it is a cold fusion related patent.

Experimental details

A cold fusion experiment usually includes:

• a metal, such as palladium or nickel, in bulk, thin films or powder;
• deuterium and/or hydrogen, in the form of water, gas or plasma; and
• an excitation in the form of electricity, magnetism, temperature, pressure, laser beam(s), or of acoustic waves.

Electrolysis cells can be either open cell or closed cell. In open cell systems, the electrolysis products, which are gaseous, are allowed to leave the cell. In closed cell experiments, the products are captured, for example by catalytically recombining the products in a separate part of the experimental system. These experiments generally strive for a steady state condition, with the electrolyte being replaced periodically. There are also "heat after death" experiments, where the evolution of heat is monitored after the electric current is turned off.

The most basic setup of a cold fusion cell consists of two electrodes submerged in a solution of palladium and heavy water. The electrodes are then connected to a power source to transmit electricity from one electrode to the other through the solution.

Excess heat observations

An excess heat observation is based on an energy balance. Various sources of energy input and output are continuously measured. Under normal condition, the energy input can be matched to the energy output to within experimental error. In experiments such as those run by Fleischmann and Pons, a cell operating steadily at one temperature transitions to operating at a higher temperature with no increase in applied current. In other experiments, however, no excess heat was discovered, and, in fact, even the heat from successful experiments was unreliable and could not be replicated independently. If higher temperatures were real, and not experimental artifact, the energy balance would show an unaccounted term. In the Fleischmann and Pons experiments, the rate of inferred excess heat generation was in the range of 10-20% of total input. The high temperature condition would last for an extended period, making the total excess heat appear to be disproportionate to what might be obtained by ordinary chemical reaction of the material contained within the cell at any one time, though this could not be reliably replicated. Many others have reported similar results.

A 2007 review determined that more than 10 groups worldwide reported measurements of excess heat in 1/3 of their experiments using electrolysis of heavy water in open and/or closed electrochemical cells, or deuterium gas loading onto Pd powders under pressure. Most of the research groups reported occasionally seeing 50-200% excess heat for periods lasting hours or days.

In 1993, Fleischmann reported "heat-after-death" experiments: he observed the continuing generation of excess heat after the electric current supplied to the electrolytic cell was turned off. Similar observations have been reported by others as well.

Reports of nuclear products in association with excess heat

Considerable attention has been given to measuring ⁴He production. In 1999 Schaffer says that the levels detected were very near to background levels, that there is the possibility of contamination by trace amounts of helium which are normally present in the air, and that the lack of detection of Gamma radiation led most of the scientific community to regard the presence of ⁴He as the result of experimental error. In the report presented to the DOE in 2004, ⁴He was detected in five out of sixteen cases where electrolytic cells were producing excess heat. The reviewers' opinion was divided on the evidence for ⁴He; some points cited were that the amounts detected were above background levels but very close to them, that it could be caused by contamination from air, and there were serious concerns about the assumptions made in the theoretical framework that tried to account for the lack of gamma rays.

In 1999 several heavy elements had been detected by other researchers, specially Tadahiko Mizuno in Japan, although the presence of these elements was so unexpected from the current understanding of these reactions that Schaffer said that it would require extraordinary evidence before the scientific community accepted it. The report presented to the DOE in 2004 indicated that deuterium loaded foils could be used to detect fusion reaction products and, although the reviewers found the evidence presented to them as inconclusive, they indicated that those experiments didn't use state of the art techniques and it was a line of work that could give conclusive results on the matter..

Neutron radiation

Fleischmann and Pons reported a neutron flux of 4,000 neutrons per second, as well as tritium, while the classical branching ratio for previously known fusion reactions that produce tritium would predict, with 1 Watt of power, the production of 10^12 neutrons per second, levels that would have been fatal to the researchers.

The Fleischmann and Pons early findings regarding helium were later retracted, and the findings regarding neutron radiation and tritium have been retracted or discredited. However, neutron radiation has been reported in cold fusion experiments at very low levels using different kinds of detectors, but levels were too low, close to background, and found too infrequently to provide useful information about possible nuclear processes. In 2008, Mosier-Boss et al. reported what they called the first scientific report of highly energetic neutrons, using CR-39 plastic radiation detectors, although some scientists say that the results will need a quantitative analysis in order to be accepted by the physics community.

Evidence for nuclear transmutations

There have been reports that small amounts of copper and other metals can appear within Pd electrodes used in cold fusion experiments. Iwamura et al. report transmuting Cs to Pr and Sr to Mo, with the mass number increasing by 8, and the atomic number by 4 in either case.. Cs or Sr was applied to the surface of a Pd complex consisting of a thin Pd layer, alternating CaO and Pd layers, and bulk Pd. Deuterium was diffused through this complex. The surface was analyzed periodically with X-ray photoelectron spectroscopy and at the end of the experiment with glow discharge mass spectrometry. Production of such heavy nuclei is so unexpected from current understanding of nuclear reactions that extraordinary experimental proof will be needed to convince the scientific community of these results.

Non-nuclear explanations for excess heat

The calculation of excess heat in electrochemical cells involves certain assumptions. Errors in these assumptions have been offered as non-nuclear explanations for excess heat.

One assumption made by Fleishmann and Pons is the efficiency of electrolysis is nearly 100%, meaning they assumed nearly all the electricity applied to the cell resulted in electrolysis of water, with negligible resistive heating and substantially all the electrolysis product leaving the cell unchanged. This assumption gives the amount of energy expended converting liquid D₂O into gaseous D₂ and O₂.

The efficiency of electrolysis will be less than one if hydrogen and oxygen recombine to a significant extent within the calorimeter. Several researchers have described potential mechanisms by which this process could occur and thereby account for excess heat in electrolysis experiments.

Another assumption is that heat loss from the calorimeter maintains the same relationship with measured temperature as found when calibrating the calorimeter. This assumption ceases to be accurate if the temperature distribution within the cell becomes significantly altered from the condition under which calibration measurements were made. This can happen, for example, if fluid circulation within the cell becomes significantly altered. Recombination of hydrogen and oxygen within the calorimeter would also alter the heat distribution and invalidate the calibration.

Discussion

Lack of accepted explanation using conventional physics

Postulating cold fusion to explain experimental results raises at least three separate problems.

1.- The probability of reaction

Because nuclei are all positively charged, they strongly repel one another. Normally, in the absence of a catalyst such as a muon, very high kinetic energies are required to overcome this repulsion. Extrapolating from known rates at high energies, the rate for uncatalyzed fusion at room-temperature energy would be 50 orders of magnitude lower than needed to account for the reported excess heat.

2.- The branching ratio

Deuteron fusion is a two-step process, in which an unstable high energy intermediary is formed:

D + D → ⁴He* + 24 MeV

High energy experiments have observed only three decay pathways for this excited-state nucleus, with the branching ratio showing the probability that any given intermediate will follow a particular pathway. The products formed via these decay pathways are:

n + ³He + 3.3 MeV (50%)

p + ³H + 4.0 MeV (50%)

⁴He + γ + 24 MeV (10⁻⁶)

Only about one in one million of the intermediaries decay along the third pathway, making its products comparatively rare when compared to the other paths. If one watt of nuclear power were produced from deuteron fusion consistent with known branching ratios, the resulting neutron and tritium (³H) production would be easily measured. Some researchers reported detecting ⁴He but without the expected neutron or tritium production; such a result would require branching ratios strongly favouring the third pathway, with the actual rates of the first two pathways lower by at least five orders of magnitude than observations from other experiments, directly contradicting mainstream-accepted branching probabilities. Those reports of ⁴He production did not include detection of gamma rays, which would require the third pathway to have been changed somehow so that gamma rays are no longer emitted.

3.- Conversion of γ-rays to heat

The γ-rays of the ⁴He pathway are not observed.. It has been proposed that the 24 MeV excess energy is transferred in the form of heat into the host metal lattice prior to the intermediary's decay. However, the speed of the decay process together with the inter-atomic spacing in a metallic crystal makes such a transfer inexplicable in terms of conventional understandings of momentum and energy transfer.

Proposed explanations

By 1998, many groups trying to replicate Fleischmann and Pons' results had found alternative explanations for their original positive results, like problems in the neutron detector in the case of Georgia Tech or bad wiring in the thermometers at Texas A&M, thus bringing most scientists to conclude that no positive result should be attributed to cold fusion, at least not in a significant scale.

Among those who continue to believe claims of Cold Fusion are not attributable to error, some possible theoretical interpretations of the experimental results have been proposed. As of 2002, according to Gregory Neil Derry, they were all ad hoc explanations that didn't explain coherently the given result, they were backed by experiments that were of low quality or non reproducible, and more careful experiments to test them had given negative results; these explanations had failed to convince the mainstream scientific community. Since cold fusion is such an extraordinary claim, most scientists would not be convinced unless either high-quality convincing data or a compelling theoretical explanation were to be found.

See also

• Bubble fusion
• Biological transmutation
• List of energy topics

Bibliography

• Adam, David (24 March 2005), Rusbringer, Alan (ed.), "In from the cold", The Guardian, retrieved 2008-05-25
• Anderson, Mark (2007), "Cold-Fusion Graybeards Keep the Research Coming", Wired Magazine, retrieved 2008-05-25 {{citation}}: Unknown parameter |month= ignored (help)
• Arata, Yoshiaki; Zhang, Yue-Chang (1998), "Anomalous difference between reaction energies generated within D₂0-cell and H₂0 Cell", Japanese Journal of Applied Physics, 37 (11A): L1274–L1276, doi:10.1143/JJAP.37.L1274
• Beaudette, Charles G. (2002), Excess Heat & Why Cold Fusion Research Prevailed, New York: Oak Grove Press, ISBN 9-9678548-2-2 {{citation}}: Check |isbn= value: checksum (help)
• Biberian, Jean-Paul (2007), "Condensed Matter Nuclear Science (Cold Fusion): An Update" (PDF), International Journal of Nuclear Energy Science and Technology, 3 (1): 31–42, doi:10.1504/IJNEST.2007.012439
• Bockris, John (2000), "Accountability and academic freedom: The battle concerning research on cold fusion at Texas A&M University", Accountability Res., 8: 103, doi:10.1080/08989620008573968
• Bowen, Jerry (April 10, 1989), "Science: Nuclear Fusion", CBS Evening News, retrieved 2008-05-25
• Broad, William J. (April 14, 1989), "Georgia Tech Team Reports Flaw In Critical Experiment on Fusion", New York Times, retrieved 2008-05-25
• Brooks, Michael (2008), 13 things that don't make sense, New York: Doubleday, ISBN 978-0-385-52068-3
• Britz, Dieter (2008), "Book review: The Science of Low Energy Nuclear Reaction", Journal of Scientific Exploration, 21 (4): 801, ISSN 0892-3310
• Browne, M. (May 3, 1989), "Physicists Debunk Claim Of a New Kind of Fusion", New York Times, retrieved 2008-05-25
• Bush, Ben F.; Lagowski, J. J.; Miles, M. H.; Ostrom, Greg S. (1991), "Helium Production During the Electrolysis of D₂O in Cold Fusion", Journal of Electroanalytical Chemistry, 304: 271–278, doi:10.1016/0022-0728(91)85510-V
• Cartwright, Jon (2009-03-23), Cold fusion: The Ghost of Free Energy, GroundReport, retrieved 2009-03-24
• Charles, Dan (1992), "Fatal explosion closes cold fusion laboratory", New Scientist, ISSN 0262-4079, retrieved 2008-08-29
• Choi, Charles (2005), "Back to Square One", Scientific American, retrieved 2008-11-25
• Chubb, Scott; et al. (2006), Session W41: Cold Fusion, American Physical Society, retrieved 2008-05-25 {{citation}}: Explicit use of et al. in: |first= (help)
• Clarke, W. Brian; Bos, Stanley J.; Oliver, Brian M. (2003), "Production of ⁴He in D₂-loaded palladium-carbon catalyst II", Fusion Science and Technology, 43 (2), American Nuclear Society: 250–255, ISSN 1536-1055, OCLC 47144540, retrieved 2008-08-31
• Close, Frank E. (1992), Too Hot to Handle: The Race for Cold Fusion (2 ed.), London: Penguin, ISBN 0-14-015926-6
• Crease, Robert; Samios, N. P. (1989), "Cold Fusion confusion", New York Times Magazine, no. September 24, 1989, p. 34-38, ISSN 0028-7822 {{citation}}: |access-date= requires |url= (help)
• Di Giulio, M.; Filippoa, E.; Mannoa, D.; Nassisi, V. (2002), "Analysis of nuclear transmutations observed in D- and H-loaded Pd films", International Journal of Hydrogen Energy, 27 (5): 527–531, doi:10.1016/S0360-3199(01)00168-9, ISSN 0360-3199 {{citation}}: Unknown parameter |month= ignored (help)
• Feder, Toni (2004), "DOE Warms to Cold Fusion", Physics Today, 57 (4): 27–28, doi:10.1063/1.1752414
• Feder, Toni (2005), "Cold Fusion Gets Chilly Encore", Physics Today, 58: 31, doi:10.1063/1.1881896 {{citation}}: More than one of |pages= and |page= specified (help); Unknown parameter |month= ignored (help)
• Fleischmann, Martin; Pons, Stanley (1989), "Electrochemically induced nuclear fusion of deuterium", Journal of Electroanalytical Chemistry, 261 (2A): 301–308, doi:10.1016/0022-0728(89)80006-3
• Fleischmann, Martin; Pons, Stanley; Anderson, Mark W.; Li, Lian Jun; Hawkins, Marvin (1990), "Calorimetry of the palladium-deuterium-heavy water system" (PDF), Journal of Electroanalytical Chemistry, 287: 293–348, doi:10.1016/0022-0728(90)80009-U
• Fleischmann, Martin; Pons, Stanley (1992), "Some Comments on The Paper 'Analysis of Experiments on The Calorimetry of LiOD-D₂O Electrochemical Cells,' R.H. Wilson et al., Journal of Electroanalytical Chemistry, Vol. 332, (1992)", Journal of Electroanalytical Chemistry, 332: 33, doi:10.1016/0022-0728(92)80339-6
• Fleischmann, Martin (1993), "Calorimetry of the Pd-D2O system: from simplicity via complications to simplicity", Physics Letters A, 176 (1–2): 118–129, doi:10.1016/0375-9601(93)90327-V
• Fleischmann, Martin (2003), "Background to cold fusion: the genesis of a concept", Tenth International Conference on Cold Fusion, Cambridge, MA: World Scientific Publishing, ISBN 978-9812565648
• Gai, M.; Rugari, S. L.; France, R. H.; Lund, B. J.; Zhao, Z.; Davenport, A. J.; Isaacs, H. S.; Lynn, K. G. (1989), "Upper limits on neutron and big gamma-ray emission from cold fusion", Nature, 340: 29–34, doi:10.1038/340029a0
• Good II, W.R. (1996), "Comments on 'Calorimetry, excess heat, and Faraday efficiency in Ni-H₂O electrolytic cells'", Fusion Technology, 30 (1): 132–133, ISSN 0748-1896
• Goodstein, David (1994), "Whatever happened to cold fusion?", American Scholar, 63 (4), Phi Beta Kappa Society: 527–541, ISSN 0003-0937, retrieved 2008-05-25
• Gozzi, D.; Cellucci, F.; Cignini, P.L.; Gigli, G.; Tomellini, M. (30 September 1997), "X-ray, heat excess and ⁴He in the D:Pd system", Journal of Electroanalytical Chemistry, 435 (1–2), Elsevier: 113–136, doi:10.1016/S0022-0728(97)00297-0
• Hagelstein, Peter; Michael, McKubre; Nagel, David; Chubb, Talbot; Hekman, Randall (2004), New Physical Effects in Metal Deuterides (PDF), Washington: US Department of Energy (manuscript)
• Hoffman, Nate (1995), A Dialogue on Chemically Induced Nuclear Effects: A Guide for the Perplexed About Cold Fusion, La Grange Park, Illinois USA: American Nuclear Society, ISBN 0-89448-558-X
• Hubler, G. K. (5 August 2007), "Anomalous Effects in Hydrogen-Charged Palladium - A Review", Surface and Coatings Technology, 201 (19–20): 8568–8573, doi:10.1016/j.surfcoat.2006.03.062from SMMIB 2005, 14th International Conference on Surface Modification of Materials by Ion Beams
• Huizenga, John R. (1993), Cold Fusion: The Scientific Fiasco of the Century (2 ed.), Oxford and New York: Oxford University Press, ISBN 0-19-855817-1
• Hutchinson, Alex (January 8, 2006), "The Year in Science: Physics", Discover Magazine (online), ISSN 0274-7529, retrieved 2008-06-20
• Iwamura, Yasuhiro; Sakano, Mitsuru; Itoh, Takehiko (2002), "Elemental Analysis of Pd Complexes: Effects of D₂ Gas Permeation", Japanese Journal of Applied Physics, 41 (7A): 4642–4650, doi:10.1143/JJAP.41.4642
• Jayaraman, K. S. (January 17, 2008), "Cold fusion hot again", Nature India, doi:10.1038/nindia.2008.77, retrieved 2008-12-07
• Jones, J. E.; Hansen, L. D.; Jones, S. E.; Shelton, D. S.; Thorne, J. M. (1995), "Faradaic efficiencies less than 100% during electrolysis of water can account for reports of excess heat in `cold fusion` cells", Journal of Physical Chemistry, 99 (18): 6973–6979, doi:10.1021/j100018a033
• Joyce, Christopher (16 June 1990), "Gunfight at the cold fusion corral", New Scientist, no. 1721, p. 22, ISSN 0262-4079, retrieved 2009-10-01
• Kainthla, R.C. (1989), "Sporadic observation of the Fleischmann-Pons heat effect", Electrochimica Acta, 34 (9): 1315–1318, doi:10.1016/0013-4686(89)85026-1 {{citation}}: Unknown parameter |month= ignored (help)
• Kozima, Hideo (2006), The Science of the Cold Fusion phenomenon, New York: Elsevier Science, ISBN 0-08-045110-1
• Krivit, Steven B. (10 April 2008), "Low Energy Nuclear Reaction Research – Global Scenario" (PDF), Current Science, 94 (7): 854–857, retrieved 2008-07-19 {{citation}}: More than one of |author= and |last= specified (help)
• Krivit, Steven (2008), "Low Energy Nuclear Reactions: The Emergence of Condensed Matter Nuclear Science", in Marwan, Jan and Krivit, Steven B., editors (ed.), Low energy nuclear reactions sourcebook, American Chemical Society/Oxford University Press, ISBN 978-0-8412-6966-8 {{citation}}: |editor= has generic name (help)CS1 maint: multiple names: editors list (link)
• Kruglinksi, Susan (2006-03-03), "Whatever Happened To... Cold Fusion?", Discover Magazine, ISSN 0274-7529, retrieved 2008-06-20
• Kowalski, Ludwik (2004), Jones’s manuscript on History of Cold Fusion at BYU, Upper Montclair, New Jersey: csam.montclair.edu, retrieved 2008-05-25
• Leggett, A.J. (1989), "Exact upper bound on barrier penetration probabilities in many-body systems: Application to cold fusion", Phys. Rev. Lett., 63: 191–194, doi:10.1103/PhysRevLett.63.191
• Lewenstein, Bruce V. (1994), Cornell cold fusion archive (PDF), collection n°4451, Division of Rare and Manuscript Collections, Cornell University Library, retrieved 2008-05-25{{citation}}: CS1 maint: location (link) CS1 maint: location missing publisher (link)
• Lewis, N. S.; Barnes†, C. A.; Heben, M. J.; Kumar, A.; Lunt, S. R.; McManis, G. E.; Miskelly, S. R.; Penner, G. M.; Sailor, M. J.; Santangelo, P. G.; Shreve, G. A.; Tufts, B. J.; Youngquist, M. G.; Kavanagh, R. W.; Kellogg, S. E.; Vogelaar, R. B.; Wang, T. R.; Kondrat, R.; New, R. (1989), "Searches for low-temperature nuclear fusion of deuterium in palladium", Nature, 340: 525–530 {{citation}}: Text "doi:10.1038/340525a0" ignored (help)
• Mallove, Eugene (1991), Fire from Ice: Searching for the Truth Behind the Cold Fusion Furor, London: Wiley, ISBN 0-471-53139-1
• Mengoli, G (1998), "Calorimetry close to the boiling temperature of the D₂O/Pd electrolytic system", Journal of Electroanalytical Chemistry, 444: 155–167, doi:10.1016/S0022-0728(97)00634-7
• McKubre, M.C.H (1994), "Isothermal Flow Calorimetric Investigations of the D/Pd and H/Pd Systems", Journal of Electroanalytical Chemistry, 368: 55, doi:10.1016/0022-0728(93)03070-6
• Miles, Melvin H.; Hollins, R. A.; Bush, Ben F.; Logowski, J. J.; Miles, R. E. (1993), "Correlation of excess power and helium production during D₂O and H₂0 electrolysis using Palladium cathodes", Journal of Electroanalytical Chemistry, 346 (1–2): 99–117, doi:10.1016/0022-0728(93)85006-3
• Mizuno, Tadahiko (1996), "Analysis of Elements for Solid State Electrolyte in Deuterium Atmosphere during Applied Field" (PDF), J. New Energy, 1 (2): 37
• Mizuno, Tadahiko; Rothwell, Jed (translator) (1998), Nuclear Transmutation: The Reality of Cold Fusion (PDF), Concord, New Hampshire: Infinite Energy Press, ISBN 1-892925-00-1 {{citation}}: |first2= has generic name (help)
• Mullins, Justin (2004), "Cold Fusion Back From the Dead", IEEE Spectrum, 41: 22, doi:10.1109/MSPEC.2004.1330805 {{citation}}: Unknown parameter |month= ignored (help)
• Mosier-Boss, Pamela A.; Szpak, Stanislaw; Gordon, Frank E. (2007), "Production of High Energy Particles Using the Pd/D Co-Deposition Process", Proceedings of the 2007 APS March Meeting, March 5–9, 2007 in Denver, College Park, Maryland: American Physical Society, retrieved 2008-05-25
• Mosier-Boss, Pamela A.; Szpak, Stanislaw; Gordon, Frank E.; Forsley, L. P. G. (2007), "Use of CR-39 in Pd/D co-deposition experiments", European Physical Journal Applied Physics, 40: 293–303, doi:10.1051/epjap:2007152
• Mosier-Boss, Pamela A.; Szpak, Stanislaw; Gordon, Frank E.; Forsley, L. P. G. (2009), "Triple tracks in CR-39 as the result of Pd–D Co-deposition: evidence of energetic neutrons", Naturwissenschaften, 96 (1): 135–142, doi:10.1007/s00114-008-0449-x
• "Texas Panel Finds No Fraud In Cold Fusion Experiments", New York Times, November 20, 1990, retrieved 2009-09-24
• Oriani, Richard A.; Nelson, John C.; Lee, Sung-Kyu; Broadhurst, J. H. (1990), "Calorimetric Measurements of Excess Power Output During the Cathodic Charging of Deuterium into Palladium", Fusion Technology, 18: 652–662, ISSN 0748-1896
• Packham, Richard A. (1989), "Production of tritium from D₂O electrolysis at a palladium cathode", Journal of Electroanalytical Chemistry, 270: 451, doi:10.1016/0022-0728(89)85059-4
• Paneth, Fritz; Peters, Kurt (1926), "Über die Verwandlung von Wasserstoff in Helium", Naturwissenschaften (in German), 14 (43): 956–962, doi:10.1007/BF01579126
• Park, Robert (2000), Voodoo Science: The Road from Foolishness to Fraud, New York: Oxford University Press, ISBN 0-19-513515-6
• Platt, Charles (1998), "What if Cold Fusion is Real?", Wired Magazine, no. 6.11, retrieved 2008-05-25
• Pollack, A. (August 26, 1997), "Japan, Long a Holdout, is Ending its Quest for Cold Fusion", New York Times, vol. 79, pp. 243, C4
• Seata, Peter N.; Schaffer, Michael J.; Morrison, Douglas R.O.; Heeter, Robert F. (October 21, 1999), "What is the current scientific thinking on cold fusion? Is there any possible validity to this phenomenon?", Scientific American, Ask the Experts, retrieved 2008-12-17 - (each author writing separately)
• Scaramuzzi, F. (2000), "Ten years of cold fusion: an eye-witness account", Accountability in Research, vol. 8, no. 1&2, p. 77, ISSN 0898-9621, OCLC 17959730 {{citation}}: |access-date= requires |url= (help) - (page numbers refer to a blocked link to an authorized reprint)
• Seife, Charles (2008), Sun in a Bottle: The Strange History of Fusion and the Science of Wishful Thinking, New York: Viking, ISBN 0670020338
• Seife, Charles (10 December 2004), "Department of Energy: Outlook for Cold Fusion Is Still Chilly", Science, vol. 306, no. 5703, p. 1834, doi:10.1126/science.306.5703.1873a, PMID 15591169, retrieved 2008-10-28 {{citation}}: More than one of |pages= and |page= specified (help)
• Shamoo, Adil E.; Resnik, David B. (2003), Oxford University Press US (ed.), Responsible Conduct of Research (2, illustrated ed.), pp. 132-133, ISBN 0195148460</ref>
• Shanahan, Kirk L. (23 May 2002), "A systematic error in mass flow calorimetry demonstrated", Thermochimica Acta, 382 (2): 95–100, doi:10.1016/S0040-6031(01)00832-2
• Shanahan, Kirk L. (2005), "Comments on "Thermal behavior of polarized Pd/D electrodes prepared by co-deposition"" (PDF), Thermochimica Acta, 428 (1–2): 207–212, doi:10.1016/j.tca.2004.11.007 {{citation}}: Unknown parameter |month= ignored (help)
• Shanahan, Kirk L. (15 February 2006), "Reply to 'Comment on papers by K. Shanahan that propose to explain anomalous heat generated by cold fusion', E. Storms, Thermochim. Acta, 2006" (PDF), Thermochimica Acta, 441 (2): 210–214, doi:10.1016/j.tca.2005.11.029, ISSN 0040-6031, OCLC 825205
• Shkedi, Zvi; McDonald, Robert C.; Breen, John J.; Maguire, Stephen J.; Veranth, Joe (1995), "Calorimetry, Excess Heat, and Faraday Efficiency in Ni-H₂O Electrolytic Cells", Fusion Technology, 28 (4): 1720–1731, ISSN 0748-1896
• Shkedi, Zvi (1996-10-26), "Response to Comments on 'Calorimetry, Excess Heat, and Faraday Efficiency in Ni-H₂O Electrolytic Cells'", Fusion Technology, 30 (1): 133, ISSN 0748-1896
• Simon, Bart (2002), Undead science: science studies and the afterlife of cold fusion (illustrated ed.), Rutgers University Press, p. 49, ISBN 0813531543, 9780813531540 {{citation}}: Check |isbn= value: invalid character (help)
• Srinivasan, M. (2008), "Meeting report: Energy concepts for the 21st century" (PDF), Current Science, 94 (7): 842–843, ISSN 0011-3891, OCLC 1565678, retrieved 10 April 2008
• Storms, Edmund (2006), "Comment on papers by K. Shanahan that propose to explain anomalous heat generated by cold fusion", Thermochimica Acta, 441 (2): 207, doi:10.1016/j.tca.2005.11.028
• Storms, Edmund (2007), Science of Low Energy Nuclear Reaction: A Comprehensive Compilation of Evidence and Explanations, Singapore: World Scientific, ISBN 9-8127062-0-8
• Szpak, Stanislaw; Mosier-Boss, Pamela A.; Miles, Melvin H.; Fleischmann, Martin (2004), "Thermal behavior of polarized Pd/D electrodes prepared by co-deposition.", Thermochimica Acta, 410: 101, doi:10.1016/S0040-6031(03)00401-5
• Szpak, Stanislaw; Mosier-Boss, Pamela A.; Young, Charles; Gordon, Frank E. (2005), "Evidence of nuclear reactions in the Pd lattice", Naturwissenschaften, 92 (8): 394–397, doi:10.1007/s00114-005-0008-7
• Tate, N. (1989), "MIT bombshell knocks fusion 'breakthrough' cold", Boston Herald, no. May 1, 1989, p. 1, ISSN 0738-5854
• Taubes, Gary (15 June 1990), "Cold fusion conundrum at Texas A&M", Science, vol. 248, pp. 1299–1304, doi:10.1126/science.248.4961.1299, PMID 17735269
• Taubes, Gary (1993), Bad Science: The Short Life and Weird Times of Cold Fusion, New York: Random House, ISBN 0-394-58456-2
• U.S. Department of Energy (1989), A Report of the Energy Research Advisory Board to the United States Department of Energy, Washington, DC: U.S. Department of Energy, retrieved 2008-05-25
• U.S. Department of Energy (2004), Report of the Review of Low Energy Nuclear Reactions (PDF), Washington, DC: U.S. Department of Energy, retrieved 2008-07-19
• Van Noorden, R. (2007), "Cold fusion back on the menu" (ASP), Chemistry World, ISSN 1473-7604, retrieved 2008-05-25 {{citation}}: Unknown parameter |month= ignored (help)
• Voss, David (March 1, 1999), "What Ever Happened to Cold Fusion", Physics World, ISSN 0953-8585, retrieved 2008-05-01
• Wilford, John Noble (April 24, 1989), "Fusion Furor: Science's Human Face", New York Times, ISSN 0362-4331, retrieved 2008-09-23
• Will, F.G. (1997), "Hydrogen + oxygen recombination and related heat generation in undivided electrolysis cells", Journal of Electroanalytical Chemistry, 426 (1): 177–184, doi:10.1016/S0022-0728(96)04972-8
• Williams, D.E.; Findlay, D.J.S.; Craston, D.H.; Sené, M.R.; Bailey, M.; Croft, S.; Hooton, B.W.; Jones, C.P.; Kucernak, A.R.J.; Mason, J.A.; Taylor, R.I. (1989), "Upper bounds on 'cold fusion' in electrolytic cells", Nature, 342: 375–384, doi:10.1038/342375a0
• Wilson, R.H. (1992), "Analysis of experiments on the calorimetry of LiOD-D₂O electrochemical cells", Journal of Electroanalytical Chemistry, 332: 1–31, doi:10.1016/0022-0728(92)80338-5

External links

• American Chemical Society, 273rd Annual Meeting, March 23, 2009, Press Conference on "Cold Fusion Rebirth." (video) Session 1, Session 2.
• The Return of Cold Fusion
• What If Cold Fusion Is Real?
• CBS 60 Minutes: Cold Fusion Is Hot Again (video) April 24, 2009
• Britz, Dieter. "Britz's COLD NUCLEAR FUSION BIBLIOGRAPHY". Retrieved 2009-06-19. Includes lists of books, articles and conferences about cold fusion.