Cold fusion

Cold fusion cell at the US Navy Space and Naval Warfare Systems Center San Diego (2005)

Cold fusion is a set of controversial effects reported in laboratory experiments, which some researchers say are caused by nuclear reactions occuring at temperatures and pressures far below those generally accepted to be required for nuclear fusion.

The first report of such an effect was published by Martin Fleischmann and Stanley Pons from the University of Utah in 1989. In their paper, they reported the observation of anomalous heating ("excess heat") of an electrolytic cell during electrolysis of heavy water using palladium electrodes. Lacking an explanation for the source of such heat, they proposed the hypothesis that the heat came from nuclear fusion of deuterium. The report of their results raised hopes of a cheap and abundant source of energy.

Cold fusion gained a reputation as pathological science after other scientists failed to replicate the results. A review panel organized by the US Department of Energy (DOE) in 1989 did not find the evidence persuasive, and said that such "nuclear fusion at room temperature [...] would be contrary to all understanding gained of nuclear reactions in the last half century" and "it would require the invention of an entirely new nuclear process."

Since then, other reports of anomalous heat production and anomalous tritium production have been reported in peer-reviewed journals^[α] and have been discussed at scientific conferences. Most scientists have met these reports with skepticism. In 2004 the US DOE organized another review panel (US DOE 2004) which—like the one in 1989—did not recommend a focused federally-funded program for low energy nuclear reactions. The 2004 panel identified basic research areas that could be helpful in resolving some of the controversies in the field. It stated that the field would benefit from the peer-review processes associated with proposal submission to agencies and paper submission to archival academic journals.

Ongoing controversy

The 1989 DOE panel said that it was not possible to state categorically that cold fusion has been convincingly either proved or disproved,. The nearly unanimous opinion of the reviewers in the 2004 review 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 skepticism towards cold fusion results from three issues: the lack of consistently reproducible results, the absence of nuclear products in quantities consistent with the excess heat, and the lack of a mainstream theoretical mechanism.

Reproducibility of the result

The cold fusion researchers who presented their review document to the 2004 DoE panel on cold fusion said 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. Despite the assertions of these researchers, most reviewers stated that the effects are not repeatable.^cf.

In 1989, the DoE panel noted that "Even a single short but valid cold fusion period would be revolutionary. As a result, it is difficult convincingly to resolve all cold fusion claims since, for example, any good experiment that fails to find cold fusion can be discounted as merely not working for unknown reasons."

Nuclear products

If the excess heat were generated by the fusion of 2 deuterium nuclei, the most probable outcome would be the generation of either a tritium nucleus and a proton, or a ³He and a neutron. The level of neutrons, tritium and ³He actually observed in Fleischmann-Pons experiment have been well below the level expected in view of the heat generated, implying that these fusion reactions cannot explain it. If the excess heat were generated by the fusion of 2 deuterium nuclei into ⁴He, a reaction which is normally extremely rare, gamma rays and helium (alpha particles) would be generated. In 1989, insufficient levels of helium (alpha particles) and gamma rays were observed to explain the excess heat.

The cold fusion researchers who presented their report to the 2004 DoE panel said that, since then, three independent studies have shown that the rate of helium (alpha particles) production measured in the gas stream varies linearly with excess power. A majority of the panelists was not convinced though.

Theoretical mechanisms

The 1989 DoE panel noted that "Nuclear fusion at room temperature, of the type discussed in this report, would be contrary to all understanding gained of nuclear reactions in the last half century; it would require the invention of an entirely new nuclear process", but it also recognized that "the failure of a theory to account for cold fusion can be discounted on the grounds that the correct explanation and theory has not been provided", that is, the lack of a satisfactory explanation could not be used to dismiss experimental evidence.

Cold fusion observations are contrary to the conventional physics of nuclear fusion in several ways :

• The average density of deuterium atoms in the palladium rod seems vastly insufficient to force pairs of nuclei close enough for fusion to occur according to mechanisms known to mainstream theories. The average distance is approximately 0.17 nanometers, a distance at which the attractive strong nuclear force cannot overcome the Coulomb repulsion. Deuterium atoms are closer together in D₂ gas molecules, which do not exhibit fusion.
• There is no known mechanism that would release fusion energy as heat instead of radiation within the relatively small metal lattice. The direct conversion of fusion energy into heat is not possible because of energy and momentum conservation and the laws of special relativity.

Cold fusion researchers have proposed various speculative theories (for a full review, see Storms 2007) to explain the reported observations, but none has received mainstream acceptance. Also, because the reported processes may not technically be fusion, the DOE calls it "low energy nuclear reaction."

Experimental reports

Cold fusion experiments have been conducted with a large variety of apparatus. The main constituents are:

• a metal, such as Palladium or Nickel, in bulk, thin films or powder;
• heavy or light water, hydrogen or deuterium gas or plasma;
• an excitation in the form of electricity, of temperature or pressure cycle, of laser beam, or of acoustic waves.

Researchers have reported the observation of excess heat, nuclear products and/or nuclear transmutations.

Excess heat

The excess power observed in some experiments is reported to be beyond that attributable to ordinary chemical or solid state sources; this excess power is attributed by proponents to nuclear fusion reactions.

The cold fusion researchers who presented their review document to the 2004 DoE panel said that "the hypothesis that the excess heat effect arises only as a consequence of errors in calorimetry was considered, studied, tested, and ultimately rejected". They said that over 50 experiments conducted by SRI International showed excess power well above the accuracy of measurement. Arata and Zhang said they observed excess heat power averaging 80 watts (1.8 times input energy) over 12 days. The researchers also said that the amount of energy reported in some of the experiments appeared to be too great compared to the small mass of the material in the cell for it to be stored by any chemical process. They said that their control experiments using light water did not show excess heat. There are nearly 200 published reports of excess heat and other reviews by cold fusion researchers reach similar conclusions.

The 2004 DoE panel noted that significant progress has been made in the sophistication of calorimeters since 1989. Evaluations by the reviewers ranged from: 1) evidence for excess power is compelling, to 2) there is no convincing evidence that excess power is produced when integrated over the life of an experiment. The reviewers were split approximately evenly on this topic.

Many of the reviewers noted that poor experiment design, documentation, background control and other similar issues hampered the understanding and interpretation of the results presented to the DoE panel. The reviewers who did not find the production of excess power convincing said that excess power in the short term is not the same as net energy production over the entire time of an experiment, that all possible chemical and solid state causes of excess heat had not been investigated and eliminated as an explanation, that the magnitude of the effect had not increased after over a decade of work, and that production over a period of time is a few percent of the external power applied and hence calibration and systematic effects could account for the purported effect.

Nuclear products

A CR-39 detector showing possible nuclear activity in cold fusion experiments at SSC San Diego.

The cold fusion researchers who presented their review document to the 2004 DoE panel on cold fusion said that there are insufficient chemical reaction products to account for the excess heat by several orders of magnitude. They said that three independent studies have shown that the rate of helium production measured in the gas stream varies linearly with excess power. Extensive precautions were taken to ensure that the samples were not contaminated by helium from the earth's atmosphere (5.2 ppm). Bursts of excess energy were time-correlated with bursts of ⁴He in the gas stream. However, the amount of helium in the gas stream was about half of what would be expected for a heat source of the type D + D -> ⁴He. Searches for neutrons and other energetic emissions commensurate with excess heat have uniformly produced null results. Although there appears to be evidence of transmutations and isotope anomalies near the cathode surface in some experiments,^{cf. and} evidence which introduce additional discrepancies between observations and conventional theory because of the increased Coulomb barrier, they said that it is generally accepted that these anomalies are not the ash associated with the primary excess heat effect. There are over 60 published reports of anomalous tritium production and other reviews by cold fusion researchers reach similar conclusions.

When asked about evidence of low energy nuclear reactions, twelve of the eighteen members of the 2004 DoE panel did not feel that there was any conclusive evidence, five found the evidence "somewhat convincing" and one was entirely convinced. The evidence of D+D fusion was taken as convincing or somewhat convincing by some reviewers; for others the lack of consistency was an indication that the overall hypothesis was not justified. Contamination of apparatus or samples by air containing 4He was cited as one possible cause for false positive results in some measurements.

In 2007, the Space and Naval Warfare Systems Center San Diego reported their observation of pits in CR-39 detectors during D/Pd codeposition experiments in the European Physical Journal. They said that those pits have features consistent with those observed for nuclear generated tracks, that the Pd cathode is the source of those pits, that they are not due to contamination or chemical reactions. They attributed some pits to knock-ons due to neutrons, and said that other pits are consistent with those obtained for alpha particles. They said that the experiment is reproducible.

Nuclear transmutations

In nuclear reactions, a chemical element may be transmuted into another. There are over 60 reports of nuclear transmutations in cold fusion experiments.^cf. Transmutations in such experiments would be contrary to all understanding gained of nuclear reactions in the last half century; they would require the invention of an entirely new nuclear process. At the same time, the lack of a satisfactory explanation cannot be used to dismiss experimental evidence.

Tadahiko Mizuno was among the first to contribute a paper (Mizuno 2000) and a book on the subject (Mizuno 1998). Dr. Miley, who also developed a process for making small inertial electrostatic confinement devices to serve as portable fusion neutron sources, wrote a review of these experiments. Some experiments result in the creation of only a few elements, while others result in a wide variety of elements from the periodic table. Calcium, copper, zinc, and iron were the most commonly reported elements. Lanthanides were also found: this is significant since they are unlikely to enter as impurities. In addition, the isotopic ratios of the observed elements differ from their natural isotopic ratio or natural abundance. The presence of an unnatural isotope ratio makes contamination an implausible explanation.

Iwamura and associates published further evidence of transmutations in the Japanese Journal of Applied Physics in 2002. Instead of using electrolysis, they forced deuterium gas to permeate through a thin layer of caesium deposited on calcium oxide and palladium, while periodically analyzing the nature of the surface through X-ray photoelectron spectroscopy. As the deuterium gas permeated over a period of a week, caesium appeared to be progressively transmuted into praseodymium. When caesium was replaced by strontium, it appeared to be transmuted into molybdenum with anomalous isotopic composition. In both cases this represents an addition of four deuterium nuclei to the original element. When the deuterium gas was replaced by hydrogen in control experiments, no transmutation was observed. The authors analyzed, and then rejected, the possibility of explaining these various observations by contaminations or migration of impurities from the palladium interior. The experiment was replicated by researchers from Osaka University, using Inductively Coupled Plasma Mass Spectrometry to analyze the nature of the surface.

Bush and Eagleton have reported the appearance of radioactive isotopes with an average half-life of 3.8 days in electrolytic cells, an observation that is difficult to explain by contamination or migration.

The original Fleischmann and Pons experiment

Electrolysis cell schematic

In their original set-up, Fleischmann and Pons used a Dewar flask (a double-walled vacuum flask) for the electrolysis, so that heat conduction would be minimal on the side and the bottom of the cell (only 5 % of the heat loss in this experiment). The cell flask was then submerged in a bath maintained at constant temperature to eliminate the effect of external heat sources. They used an open cell, thus allowing the gaseous deuterium and oxygen resulting from the electrolysis reaction to leave the cell (with some heat too). It was necessary to replenish the cell with heavy water at regular intervals. The authors said that, since the cell was tall and narrow, the bubbling action of the gas kept the electrolyte well mixed and of a uniform temperature. The efficacy of this stirring method and thus the validity of the temperature measurements would later be disputed. Special attention was paid to the purity of the palladium cathode and electrolyte to prevent the build-up of material on its surface, especially after long periods of operation.

The cell was also instrumented with a thermistor to measure the temperature of the electrolyte, and an electrical heater to generate pulses of heat and calibrate the heat loss due to the gas outlet. After calibration, it was possible to compute the heat generated by the reaction.

A constant current was applied to the cell continuously for many weeks, and heavy water was added as necessary. For most of the time, the power input to the cell was equal to the power that went out of the cell within measuring 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, for durations of 2 days or more. The generated power was calculated to be about 20 times the input power during the power bursts. Eventually the power bursts in any one cell would no longer occur and the cell was turned off.

This experiment has been critiqued by Wilson, Shkedi and Jones. Cold fusion researchers find these critique unconvincing, and not applicable to other experimental design.

History

Early work

Cold fusion revolves around the idea that palladium or titanium might catalyze fusion stemmed from the special ability of these metals to absorb large quantities of hydrogen, including its deuterium isotope, the hope being that the deuterium atoms would be close enough together to induce fusion at ordinary temperatures. The special ability of palladium to absorb hydrogen was recognized as early as the nineteenth century by Thomas Graham. In the late nineteen-twenties, two German scientists, F. Paneth and K. Peters, reported the transformation of hydrogen into helium by spontaneous nuclear catalysis when hydrogen was adsorbed by finely divided palladium at room temperature. These authors later acknowledged 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 coined by Dr Paul Palmer of Brigham Young University in 1986 in an investigation of "geo-fusion," or the possible existence of fusion in a planetary core.

Pre-announcement and announcement

In the 1960s, Fleischmann and his research team began investigating the possibility that chemical means could influence nuclear processes. Simple quantum mechanical calculations indicate that such effects should be negligibly small, but Fleischmann started to explore whether collective effects, that would require quantum electrodynamics to calculate, might be significant. By 1983, Fleischmann had experimental evidence leading him to believe that condensed phase systems developed coherent structures up to 10^-7m in size.

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, including Steven E. Jones of Brigham Young University. Jones had worked on muon-catalyzed fusion for some time, and had written an article on the topic entitled Cold Nuclear Fusion that had been published in Scientific American in July 1987. Similar to Fleischmann and Pons, Jones claimed that he detected fusion but with a more modest claim, but it was discredited because the rates were far too low to be commercially practical.

Both Fleischmann and Pons`, and Jones research teams met on occasion in Utah to discuss sharing 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. This could bear significant commercial value and would be protected by patent protection. Jones, however, was measuring neutron flux, which was not of commercial interest. In order to avoid problems in the future, the teams apparently agreed to simultaneously publish their results, although their accounts of their March 6 meeting differ.

In mid-March, 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, 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 announcement was made.

Post-announcement

The press initially reported on the experiments widely, and due to the surmised beneficial commercial applications of the Utah experiments, "scores of laboratories in the United States and abroad" attempted to repeat the experiments.

On April 10, 1989, Fleischmann and Pons, who later suggested pressure from patent attorneys, published a rushed "preliminary note" in the Journal of Electroanalytical Chemistry. This paper notably contained a gamma peak without its corresponding Compton edge, a discrepancy that triggered accusations of fraud. Their "preliminary note" was followed up a year later in July 1990, when a much longer paper, going into details of calorimetry but without any nuclear measurements, was published in the same journal.

Also occurring on April 10, a team at Texas A&M University published their results of excess heat, followed up by a team at the Georgia Institute of Technology in regards to neutron production. Both results were widely reported on in the press, although both Texas A&M and Georgia Institute of Technology withdrew their results for lack of evidence. For the next six weeks, additional competing claims, counterclaims and suggested explanations kept the topic of Cold Fusion paramount, and led some journalists refer to the situation as "fusion confusion."^cf.

On April 12, Pons received a standing ovation from about 7,000 chemists at the semi-annual meeting of the American Chemical Society. The University of Utah asked Congress to provide $25 million to pursue the research, and Pons was scheduled to meet with representatives of President Bush early May.

One month later, on May 1, the American Physical Society held a session on cold fusion, reported a string of failed experiments. A second session began the next day with other negative reports, and eight of the nine leading speakers stated that they ruled the initial Utah claim as dead. Dr. Steven E. Koonin of Caltech called the Utah report a result of "the incompetence and delusion of Pons and Fleischmann." Dr. Douglas R. O. Morrison, a physicist representing CERN, called the entire episode an example of pathological science.

In July, the first successful replication of the excess heat was completed by Richard Oriani, a professor of physical chemistry at the University of Minnesota. The results were published in his paper, "Calorimetric Measurements of Excess Power Output During the Cathodic Charging of Deuterium Into Palladium," in Fusion Technology. Nature published papers critical of cold fusion in July and November.

In November, a special panel formed by the Energy Research Advisory Board, under a charge of the United States Department of Energy, reported the result of their investigation into cold fusion. The scientists in the panel found the evidence for cold fusion to be unconvincing. Nevertheless, the panel was "sympathetic toward modest support for carefully focused and cooperative experiments within the present funding system."

In 1991, Dr. Eugene Mallove stated that the negative report issued by MIT's Plasma Fusion Center in 1989, which was highly influential in the controversy, was fraudulent because data was shifted without explanation, and as a consequence, this action obscured a possible positive excess heat result at MIT. In protest of MIT's failure to discuss and acknowledge the significance of this data shift, Mallove resigned from his post of chief science author at the MIT news office on June 7, 1991. He maintained that the data shift was biased to support the conventional belief in the non-existence of the cold fusion effect as well as to protect the financial interests of the plasma fusion center's research in hot fusion.

Nobel Laureate Julian Schwinger also stated in 1991 that he had experienced "the pressure for conformity in editor's rejection of submitted papers, based on venomous criticism of anonymous reviewers," and that "the replacement of impartial reviewing by censorship will be the death of science." He resigned as Member and Fellow of the American Physical Society, in protest of its peer review practice on cold fusion.

In 1992, General Electric challenged the Fleischmann-Pons 1990 report in the Journal of Electroanalytical Chemistry, stating that the claims of excess heat had been overstated. The challenge concluded that the Fleischmann and Pons cell generated 40% excess heat, more than ten times larger than the initial error estimate. Despite the apparent confirmation, Fleischmann and Pons replied to General Electric and published a rebuttal in the same journal.

Moving beyond the initial controversy

Fleischmann and Pons relocated their laboratory to France under a grant from the Toyota Motor Corporation.

By 1991, 92 groups of researchers from 10 different countries had reported excess heat, tritium, neutrons or other nuclear effects. Over 3,000 cold fusion papers have been published including about 1,000 in peer-reviewed journals (see indices in further reading, below). In March 1995, Dr. Edmund Storms compiled a list of 21 published papers reporting excess heat and articles have been published in peer reviewed journals such as Naturwissenschaften, European Physical Journal A, European Physical Journal C, Journal of Solid State Phenomena, Physical Review A, Journal of Electroanalytical Chemistry, Japanese Journal of Applied Physics, and Journal of Fusion Energy (see indices in further reading, below).

Michael McKubre working on a deuterium gas-based cold fusion cell used by SRI International

The generation of excess heat has been reported by (among others):

• Michael McKubre, director of the Energy Research Center at SRI International,
• Giuliano Preparata (ENEA (Italy))
• Richard A. Oriani (University of Minnesota, in December 1990),
• Robert A. Huggins (at Stanford University in March 1990),
• Y. Arata (Osaka University, Japan),
• T. Mizuno (Hokkaido University, Japan),
• T. Ohmori (Japan),

The most common experimental set-ups are the electrolytic (electrolysis) cell and the gas (glow) discharge cell, but many other set-ups have been used. Electrolysis is popular because it was the original experiment and is the more commonly known way of conducting the cold fusion experiment; gas discharge is often used because it is believed to be the set-up that provides an experimenter a better chance at replication of the excess heat results.

Researchers share their results at the International Conference on Cold Fusion, recently renamed International Conference on Condensed Matter Nuclear Science. The conference is held every 12 to 18 months in various countries around the world, and is hosted by The International Society for Condensed Matter Nuclear Science, a scientific organization that was founded as a professional society to support research efforts and to communicate experimental results. A few periodicals emerged in the 1990s that covered developments in cold fusion and related new energy sciences (Fusion Facts, Cold Fusion Magazine, Infinite Energy Magazine, New Energy Times).

A cold fusion calorimeter of the open type, used at the New Hydrogen Energy Institute in Japan. Source: SPAWAR/US Navy TR1862

Between 1992 and 1997, Japan's Ministry of International Trade and Industry sponsored a "New Hydrogen Energy Program" of $20 million to research cold fusion. Announcing the end of the program, Dr. Hideo Ikegami stated in 1997 "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, Dr. 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.

Cold fusion researchers said that cold fusion is suppressed, and that skeptics suffer from "pathological disbelief". They said that there is virtually no possibility for funding in cold fusion in the United States, and no possibility of getting published. They said that people in universities refuse to work on it because they would be ridiculed by their colleagues.

In February 2002, a laboratory within the United States Navy released a report that came to the conclusion that the cold fusion phenomenon was in fact real and deserved an official funding source for research. Navy researchers have published more than 40 papers on cold fusion.

In 2004, the United States Department of Energy (USDOE) decided to take another look at cold fusion to determine if their policies towards cold fusion should be altered due to new experimental evidence. In 2007, DARPA sponsored an international research project on cold fusion. In 2008, the government of India reviewed the field. Dr. M. R. Srinivasan, former chairman of the Atomic Energy Commission of India said: "There is some science here that needs to be understood. We should set some people to investigate these experiments. There is much to be commended for the progress in the work. The neglect should come to an end".

Other kinds of fusion

Some other kinds of fusion may be termed "cold" in some sense but are separate from the cold fusion controversy. "Cold" may be taken in the sense that no part of the reaction is actually hot (except for the reaction products), or that the energies required are low and the bulk of the material is at a relatively low temperature. Some other kinds of fusion are "hot", involving reactions which create macroscopic regions of very high temperature and pressure.

Locally cold fusion

• Muon-catalyzed fusion is a well-established and reproducible fusion process which occurs at low temperatures. It has been studied in detail by Steven Jones in the early 1980s. However, because of the energy required to create muons, it is not able to produce net energy.

Generally cold, locally hot fusion

• In cluster impact fusion, microscopic droplets of heavy water (on the order of 100-1000 molecules) are accelerated to collide with a target, so that their temperature at impact reaches at most 10⁵ kelvin, 10,000 times smaller than the temperature required for hot fusion. In 1989, Friedlander and his coworkers observed 10¹⁰ more fusion events than expected with standard fusion theory. Recent research^cf. suggests that the calculation of effective temperature may have failed to account for certain molecular effects which raise the effective collision temperature, so that this is a microscopic form of hot fusion.

• In sonoluminescence, acoustic shock waves create temporary bubbles that collapse shortly after creation, producing very high temperatures and pressures. In 2002, Rusi P. Taleyarkhan explored the possibility that bubble fusion occurs in those collapsing bubbles. If this is the case, it is because the temperature and pressure are sufficiently high to produce hot fusion.

• The Farnsworth-Hirsch Fusor is a tabletop device in which fusion occurs. This fusion comes from high effective temperatures produced by electrostatic acceleration of ions. The device can be built inexpensively, but it too is unable to produce a net power output.

• Antimatter-catalyzed fusion uses small amounts of antimatter to trigger a tiny fusion explosion. This has been studied primarily in the context of making nuclear pulse propulsion feasible.

Several of these systems are "nonequilibrium systems", in which very high temperatures and pressures are produced in a relatively small region adjacent to material of much lower temperature. In his doctoral thesis for Massachusetts Institute of Technology, Todd Rider did a theoretical study of all non-equilibrium fusion systems. He demonstrated that all such systems will leak energy at a rapid rate due to Bremsstrahlung, radiation produced when electrons in the plasma hit other electrons or ions at a cooler temperature and suddenly decelerate. The problem is not as pronounced in a hot plasma because the range of temperatures, and thus the magnitude of the deceleration, is much lower.

Hot fusion

• "Standard" fusion, in which the fuel reaches tremendous temperature and pressure inside a fusion reactor, nuclear weapon, or star.

Notes

• α.^{^} References to publications are listed in Storms 2007, pp. 52–61, 79–81 and in Hagelstein et al. 2004, pp. 25–29, to include Arata & Zhang 1998, Iwamura, Sakano & Itoh 2002, Mizuno et al. 2000, Miles et al. 1993 and Bush et al. 1991. Electrochemist Dr. Dieter Britz, who has remained neutral on the question of whether cold fusion exists, has compiled a cold fusion bibliography which includes 479 published scientific journal articles marked "res+" indicating positive research results.

Bibliography

• Anderson, Mark (2007), "Cold-Fusion Graybeards Keep the Research Coming", Wired Magazine, 2007 (8)

• 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.

• 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", International Journal of Nuclear Energy Science and Technology, 3 (1): 31–43, doi:10.1504/IJNEST.2007.012439.

• Bowen, Jerry (1989), "Science: Nuclear Fusion", CBS Evening News, no. April 10, 1989.

• Broad, William J. (April 14, 1989), "Georgia Tech Team Reports Flaw In Critical Experiment on Fusion", New York Times{{citation}}: CS1 maint: date and year (link).

• Browne, M. (May 3, 1989), "Physicists Debunk Claim Of a New Kind of Fusion", New York Times{{citation}}: CS1 maint: date and year (link).

• Bush, Ben F.; Ostrom, Greg S. (1991), "Helium Production During the Electrolysis of D₂O in Cold Fusion", Journal of Electroanalytical Chemistry, 304: 271–278.

• Bush, R. T.; Eagleton, R.D. (1994), "Evidence of electrolytically induced transmutation and radioactivity correlated with excess heat in Electrolytic cells with light water rubidium salt electrolytes", Transactions of Fusion Technology, 26 (4T).

• Chubb, Scott; et al. (2006), Session W41: Cold Fusion, Proceedings of the 2006 APS March Meeting, March 13–17, 2006 in Baltimore, College Park, MD: American Physical Society {{citation}}: Explicit use of et al. in: |first= (help).

• Close, Frank E. (1991), Too Hot to Handle: The Race for Cold Fusion, Princeton, N.J.: Princeton University Press, ISBN 0-691-08591-9.

• Crease, Robert; Samios, N. P. (1989), "Cold Fusion confusion", New York Times Magazine (September 24, 1989): 34-38 {{citation}}: |access-date= requires |url= (help)

• Evans, Robley D. (1982), The Atomic Nucleus, New York: Krieger Publishing, ISBN 0-89874-414-8.

• Feder, Toni (2004), "DOE Warms to Cold Fusion", Physics Today, 57 (4): 27–28

• Feder, Toni (2005), "Cold Fusion Gets Chilly Encore", Physics Today: 31

• Fleischmann, Martin; Pons, Stanley (1989), "Electrochemically induced nuclear fusion of deuterium", Journal of Electroanalytical Chemistry, 261 (2A): 301–308.

• Fleischmann, Martin; Pons, Stanley; Anderson, Mark W.; Li, Lian Jun; Hawkins, Marvin (1990), "Calorimetry of the palladium-deuterium-heavy water system", Journal of Electroanalytical Chemistry, 287: 293–348

• 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

• 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

• Goodstein, David (1994), "Whatever happened to cold fusion?", The American Scholar, 63 (4): 527–541.

• Hagelstein, Peter; Michael, McKubre; Nagel, David; Chubb, Talbot; Hekman, Randall (2004), New Physical Effects in Metal Deuterides (PDF), Washington: USDOE

• Higashiyama, Taichi; Sakano, Mitsuru; Miyamaru, Hiroyuki; Takahashi, Akito (2003), "Replication of MHI Transmutation Experiment by D2 Gas Permeation Through Pd Complex", Tenth International Conference on Cold Fusion, Cambridge, MA: publisher=World Scientific Publishing Company, ISBN 978-9812565648 {{citation}}: Missing pipe in: |publisher= (help)

• Hubler, G. K. (2007), "Anomalous Effects in Hydrogen-Charged Palladium - A Review", Surface and Coatings Technology, 201 (19–20): 8568–8573, doi:10.1016/j.surfcoat.2006.03.062

• Huizenga, John R. (1992), Cold Fusion: The Scientific Fiasco of the Century, Rochester, N.Y.: University of Rochester Press, ISBN 1-878822-07-1.

• Hutchinson, Alex (January 2006), "The Year in Science: Physics", Discover{{citation}}: CS1 maint: year (link)

• 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.

• Iwamura, Yasuhiro (2004), "Observation of Nuclear Transmutation Reactions induced by D2 Gas Permeation through Pd Complexes", Eleventh International Conference on Condensed Matter Nuclear Science, Marseille, France: World Scientific Publishing Company, ISBN 978-9812566409

• Jayaraman, K. S. (Jan 17, 2008), "Cold fusion hot again", Nature India, doi:10.1038/nindia.2008.77{{citation}}: CS1 maint: date and year (link)

• 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

• Josephson, Brian. D. (2004), Pathological Disbelief (PDF), Lecture given at the Nobel Laureates’ meeting Lindau, June 30th., 2004 {{citation}}: Unknown parameter |auhtorlink= ignored (help).

• Kee, B (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{{citation}}: CS1 maint: date and year (link).

• Kim, Y. E.; Yoon, J.-H.; Rice, R. A.; Rabinowitz, Mario (1992), "Cluster-Impact Fusion and Effective Deuteron Temperature", Physical Review Letters, 68 (3): 373–376.

• Kozima, Hideo (2006), The Science of the Cold Fusion phenomenon, New York: Elsevier Science, ISBN 0-08-045110-1.

• Krivit, Steven B. (2005), "The Seminal Papers of Cold Fusion", New Energy Times.

• Krivit, Steven B. (2007), "Extraordinary Courage: Report on Some LENR Presentations at the 2007 American Physical Society Meeting", New Energy Times (March 16, 2007).

• Krivit, Steven B. (2007b), "International Collaboration Advances LENR Frontier", New Energy Times (25).

• Krivit, Steven B. (2008), "Low Energy Nuclear Reaction Research – Global Scenario" (PDF), Current Science, 94 (7): 854–857.

• Kowalski, Ludwik (2004), Jones’s manuscript on History of Cold Fusion at BYU, Upper Montclair, NJ: csam.montclair.edu

• Lewenstein, Bruce V. (1994), Cornell cold fusion archive (PDF)

• Mallove, Eugene (1991), Fire from Ice: Searching for the Truth Behind the Cold Fusion Furor, London: Wiley, ISBN 0-471-53139-1.

• Mallove, Eugene (1999), "MIT and Cold Fusion: A Special Report" (PDF), Infinite Energy Magazine, 24

• 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.

• Miley, George H.; Shrestha, P. (2003), "Review Of Transmutation Reactions In Solids", Proceedings of the Tenth International Conference on Cold Fusion, Cambridge, MA: World Scientific Publishing Company, ISBN 978-9812565648

• Mizuno, Tadahiko (1998), Nuclear Transmutation: The Reality of Cold Fusion, Concord, NH: Infinite Energy Press{{citation}}: CS1 maint: location missing publisher (link).

• Mizuno, Tadahiko; Ohmori, Tadayoshi; Akimoto, Tadashi; Takahashi, Akito (2000), "Production of Heat During Plasma Electrolysis in Liquid", Japanese Journal of Applied Physics, 39 (10): 6055–6061.

• Mizuno, Tadahiko (2000), "Experimental Confirmation of the Nuclear Reaction at Low Energy Caused by Electrolysis in the Electrolyte", Proceeding for the Symposium on Advanced Research in Technology, Hokkaido University, March 15-17, 2000, pp. 95–106.

• 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, MD: American Physical Society. *slides*

• 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

• New Energy Times, "MIT Allegations of Fleischmann and Pons Fraud", New Energy Times

• Oriani, Richard A.; Nelson, John C.; Lee, Sung-Kyu; Broadhurst, J. H. (1990), Fusion Technology, vol. 18, pp. 652–662.

• Park, Robert (2000), Voodoo Science: The Road from Foolishness to Fraud, New York: Oxford University Press, ISBN 0-19-513515-6.

• Platt, Charles (1989), "What If Cold Fusion Is Real?", Wired Magazine (6.11)

• Pollack, A. (1997), "Japan, Long a Holdout, Is Ending Its Quest for Cold Fusion", New York Times, no. August 26, 1997, p. C4.

• Prow, Tina M. (2001), "George Miley: Harnessing fusion as an energy source", Engineering Outlook, 41 (2)

• Rusbringer, Alan, ed. (2005), "In from the cold", The Guardian (March 24, 2005)

• Schwinger, Julian (1991), "Cold fusion—Does it have a future?", in Suzuki, Masuo; Kubo, Ryogo (eds.), Evolutionary Trends in the Physical Sciences: Proceedings of the Yoshio Nishina Centennial Symposium, Tokyo, Japan, December 5-7, 1990, Springer Proceedings in Physics, vol. 57, Berlin: Springer Verlag, pp. 171–175, ISBN 3-540-54568-9.

• Shkedi, Zvi; McDonald, R.C.; Breen, J.J.; Maguire, S.J.; Veranth, J. (1995), "Calorimetry, Excess Heat, and Faraday Efficiency in Ni-H₂O Electrolytic Cells.", Fusion Technology, 28 (4): 1720–1731.

• Shkedi, Zvi (1996), "Response to Comments on 'Calorimetry, Excess Heat, and Faraday Efficiency in Ni-H₂O Electrolytic Cells'", Fusion Technology, 30 (???): 133.

• Srinivasan, M. (2008), "Energy concepts for the 21st century" (PDF), Current Science, 94 (7): 842–843

• 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.; 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.

• Szpak, Stanislaw; Mosier-Boss, Pamela A., eds. (2002a), Thermal and nuclear aspects of the Pd/D2O system - Volume 1:A decade of research at Navy laboratories (PDF), Technical report 1862, San Diego: Office of Naval Research/Space and Naval Warfare Systems Center.

• Szpak, Stanislaw; Mosier-Boss, Pamela A., eds. (2002b), Thermal and nuclear aspects of the Pd/D2O system - Volume 2:Simulation of the electrochemical cell (ICARUS) calorimetry (PDF), Technical report 1862, San Diego: Office of Naval Research/Space and Naval Warfare Systems Center {{citation}}: Cite has empty unknown parameter: |1= (help).

• Tate, N. (1989), "MIT bombshell knocks fusion 'breakthrough' cold", Boston Herald, no. May 1, 1989, p. 1.

• 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: US DOE.

• U.S. Department of Energy (2004), Report of the Review of Low Energy Nuclear Reactions (PDF), Washington, DC: doe.gov.

• Van Noorden, R. (2007), "Cold fusion back on the menu", Chemistry World (April 2007).

• Will, F. G. (1997), "Hydrogen + oxygen recombination and related heat generation in undivided electrolysis cells", Journal of Electroanalytical Chemistry, 426 (1): 177–184.

• 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.

Further reading

• Lenr-Canr Library of more than 500 original scientific papers on cold fusion.
• Recent papers on cold fusion listed on New Energy Times
• New Energy Times book index Extensive index of books on cold fusion
• Britz's cold nuclear fusion bibliography: An extensive overview and review of almost all available publications on the subject of cold nuclear fusion.
• A student's guide to Cold Fusion: a technical introduction to the field by Edmund Storms.