Cold Fusion, aka Low Energy Nuclear Reactions (L.E.N.R.)

A 1989 cover of Time Magazine

Cold fusion, more recently referred to as Low energy nuclear reactions (LENR), gained a large amount of media attention from 1989-93. Since that time, the search for this sustainable energy source has branched into a clearly pseudo-scientific discipline, and one that is more difficult to define. Throughout the wiki entry there will be several videos. These are meant to supplement the information on the page, in some cases in the words of the scientists involved themselves.

About Cold Fusion

Cold fusion is defined as fusion reaction which can be safely be carried out at room temperature. This is contrasted with hot fusion, which refers to the process which fuels our sun and is highly unstable.


On March 22, 1989 one of the world's leading electrochemists, Martin Fleischmann, and his colleague and former pupil Stanley Pons submitted their paper on what they would go on to call cold fusion (Taubes, 1993). The next day a press conference was held; a press conference that would launch a media frenzy and obsession over this potential energy source. Here they presented an experiment involving a current passing between two Palladium and platinum plates submerged in Lithium Deuteroxide (Taubes, 1993). They claimed to have created a system in which hydrogen from heavy water was being turned into helium. The result was a very exothermic reaction, or
Fleischman explaining the apparatus to a politician.
so they claimed. After the announcement, attempts to replicate their findings were unable to create the amounts of energy claimed by Fleischmann and Pons (Salamon et al, 1990. Williams et al, 1989). The two scientists had rushed together their findings to beat another researcher, Steven Jones, to the punch (Taubes, 1993). Though this rush to publish their findings is often credited for the poor reception from the scientific community, the problems I will address is later sections account for it satisfactorily.

Though Fleischmann and Pons sparked the controversial subject, there have been several other inventors and researchers who have claimed to build cold fusion devices in addition to a handful of papers on the subject prior to 1989. The theory behind cold fusion has been often revised, with notable examples like Lewis Larson who developed the Widon-Larson theory, which is the foundation for experiments being done on LENR by NASA's Joseph Zawodny(Anderson, 2012).
Since the advent of YouTube many amateur physicists, in addition to documentary makers who focus on alternative science, have been posting videos claiming to replicate either the Fleischmann-Pons experiment, or those similar to it.

Theoretical Principles

The defining feature of a low energy nuclear reaction
is that the elements involved must change their mass. Otherwise the reaction is chemical and not nuclear. The
Fleischmann-Pons paper shows a pathway for fusion to come about in the apparatus. The following reactions must take place:

D2O + e- → D+ + OD
D+ + D2O + e- → D2 + OD
D+ → Dlattice
D++ D+ → D2
2D + 2D → 3T(1.01 MeV) + 1H(3.02 MeV)
2D + 2D → 3He(0.82 MeV) + n(2.45 MeV) (Fleischmann, 1989)

In easier to understand terms, the heavy water dissolves into its two ions, ionized deuterium and OD. Then the ionized deuterium is absorbed into the lattice like a sponge, where it comes into contact with more and more ionized deuterium. Eventually, the energy from the current causes two particles of ionized deuterium to fuze resulting in either a helium atom or even heavier isotopes of hydrogen. This fusion reaction creates a lot of energy, which can in theory be used to heat water, and thus create electricity.

Cold Fusion Today

I will be distinguishing between two branches of the cold fusion community. The first I will continue to call cold fusion, and the second I will refer to as LENR. The purpose of this distinction is to not confuse two very different groups. In this section I will clarify the difference between both factions.

Cold Fusion

The group to which I will be referring as cold fusion advocates are those people who maintain that the Fleischmann-Pons type experiments have either always worked, are working now. Also characteristic of this group are conspiracy theories which claim the findings about cold fusion are being suppressed (Arnolds, 2012). Today, this group shares its ideas mainly on the internet and alternative science magazines. This group is informed by a mixture of wishful thinking, poor logic and misinterpretations of publications from the LENR group. Very often members of this group are also believers in other pseudoscience, for example ufology, extrasensory perception or parapsychology. Organizations that promote cold fusion, here I am using the term specifically to refer to this group, are disassociated from academic institutions. Another feature of cold fusion advocates is that they tend to make claims about the coming wide spread availability of commercial cold fusion devices. One such device is called E-Cat, invented by an engineer named Andrea Rossi (Acland, 2013). Websites that give support to the invention often refer to the experiment being replicated several times, but give no citations. In fact, a simple Google scholar search returns no peer reviewed articles supporting E-Cat. For this reason it is grouped with the original Fleischmann-Pons device which could not replicate results.


The second division of the cold fusion community is, although at the moment they have the same lack of laboratory evidence to support their theory, they possess the backing of respected organizations like NASA (Anderson, 2012). I will be referring to subsection of the community as LENR, because that is the more accurate term for the intended reaction in cold fusion. As I mentioned earlier, the term is used by Lewis Larson in his 2006 paper "Ultra Low Momentum Neutron Catalyzed Nuclear Reactions on Metallic Hydride Surfaces" coauthored with Allan Widom of Northeastern University. The theory proposed in the paper is being used to develop new experiments to test the phenomenon. This group is differentiate from the cold fusion group, as it will become clearer later on, in that this group differentiates themselves from the cold fusion commotion. They claim a different process, and they go about proving it differently.

But is Cold Fusion Science?

Cold Fusion

In short, no. Such a short answer is kinder than many scientists may be inclined to give. First, let us consider the original Fleischmann-Pons experiment. The problem that the scientific community had with it was that it was not replicable (Salamon et al, 1990. Williams et al, 1989). The experiment would not give off the amount of energy for any other researcher as it did for Fleischmann and Pons.
The experiments that people now call cold fusion, like in the first YouTube video above, are not nuclear reactions, but chemical ones. The light and heat produced in the reaction are not from fusion, but rather the combustion of hydrogen. Cold fusion is in a sense science; it is chemistry. But it is not what it claims to be, a nuclear physics project. It is not the science it claims to be.
The E-Cat device is not science either. If any label would fit it best, it would be a business. As the video featuring James Randi shows, the commitment of E-Cat owners and Rossi are to making money and not to scientific progress. The owners of any revolutionary product, like a cold fusion reactor, should welcome the publicity that repeatability would bring.
Last is the group of cold fusion advocates who are characterized by experiments carried out in a garage in the suburbs. This too is clearly not science. It does not seek to follow the scientific method but to recreate an experiment which never worked to begin with. There are no hypotheses or null hypotheses, only building a machine.


The main reason why this article breaks down the cold fusion community into these two groups is because there is some semblance of the scientific method in the proposed experiments by Joseph Zawodny et. al. These NASA funded experiments investigate some of the consequences of fusion that are missing in previous endeavours. Zawodny has built detectors (Anderson, 2012) to monitor the radiation which comes from a fusion reaction, instead of only investigating the heat output. They predict what will hit the detectors as a result of the Windom-Larson paper. Where as the prior cold fusion experiments measure the energy created, which could just as easily be created by chemical processes, only a nuclear reaction would emit subatomic particles. Whereas the above group of cold fusion advocates seemed to disregard established science, for example the coulomb barrier, these researchers have made sure that their hypotheses are compatible with previous discoveries.

Why is Cold Fusion Pseudoscience?

What Makes Makes Something as Pseudoscience?

There are several prevalent demarcation theories in the philosophy of science. These methods are necessary to having a successful epistemology. If we cannot distinguish good science from pseudoscience, then we will not be able to strive for knowledge the way we desire to as humans. I will be considering Poppers criterion of falsification, Thagard's criteria. Other notable methods of demarcation include the logical positivists criteria of verificationism and epistemic norms.


Karl Popper, in his essay “Science as Falsification”, writes in an attempt to distinguish hard sciences from pseudosciences such as Freud’s psychoanalysis. Popper writes about this and other pseudosciences, and makes the obvious concession that science is fallible and that pseusciences can arrive at truth by chance. Thus the criteria for what is science cannot be its veracity, but something else. Popper contrasts Einstein’s general relativity with psychoanalysis. There are glaring differences in the nature of the claims that each theory makes. When comparing the two theories, I will refer to them simply by the author with which they are associated: Einstein and Freud. The first difference that Popper considers is that Einstein makes specific claims. While other pseudosciences like astrology mig
Karl Popper
ht fail in this respect Freud seems to, in fact, make specific claims. Just as the statement ‘The light from distant stars will be bent by our sun’s gravity,’ is specific, so is “the reason that Jerry acts out in aggression is that he is attracted to his mother’. However, the two statements are very different. Popper would explain the difference as deriving from the way that Freud has a statement ready for every scenario. That everybody is obsessed with their opposite sexed parents is very different from one set of specific predictions about the effect gravity has. The defining feature of relativity’s statements is that had the experiments turned out one way instead of another, relativity would have been disproved. Whereas if we show that Jerry wasn’t at all even considering his mother when he acts, Freud will still have some ad hoc explanation for us. Popper also requires these specific predictions to be risky. This is the difference of predicting the sun will come up tomorrow and the predictions I have attributed to Einstein already. The last feature that Popper identifies is prohibitory statements. This is related to the risky prediction requirement. A scientific theory should make claims that if certain evens should come about, or certain results found through independent experiments, that the theory be considered disproved. If we were to find beams of light traveling in straight lines past massive objects, then general relativity would be doubted. In contrast the psychoanalyst makes only positive claims.

Paul Thagard from the University of Waterloo
Paul Thagard from the University of Waterloo

Paul Thagard in his paper, “Why Astrology is a Pseudoscience,” disagrees with Poppers criteria of demarcation. He argues for his position, which the Stanford Encyclopedia of philosophy calls Criteria based on scientific progress, by showing how the accounts of why astrology is pseudoscience given by each competing demarcation method are unsatisfactory. He begins with the criteria for demarcation that science must be founded on an empirical world view and not a magical one. The finds this inadequate as the scientific status of the beliefs that led to a discipline should not affect it. The most obvious example of a legitimate science which was arrived at from a magical world view is chemistry. Alchemy was the search for a method to change base metals into gold and to craft the elixir of life; this was a study which held a firmly magical world view. If it necessary for science to trace itself back to an empirical worldview, then we cannot count chemistry among what we consider science. This is clearly not correct. Thagard strengthens his argument by giving examples of several sciences which were built from mere speculation, a trait that can hardly be considered empirical.
The second demarcation criteria Thagard addresses is verificationism, or that hypotheses must be verifiable. He criticizes attempts to characterize science as only the studies that are able to be tested. Scientific statements must be capable of being either true or false, which is in keeping with the logical positivist tradition. Thagard calls this requirement a “Vague sense of testability,” (Thagard, 1978). In this vein, he reasons that astrology is vaguely testable, and thus verificationism is not sufficient to demark pseudoscience. Though this seems like shallow wordplay, Thagard’s larger point is that statistical analysis can be carried out on the claims of astrology and, according to the work he cites, this analysis can seem to prove astrology. Yet we still are not willing to consider it science.
In the ark of the argument, we now arrive at Thagard’s treatment of Popper. Popper’s demarcation criteria seem to solve all the problems Thagard has addressed up to this point. Thagard finds fault in the criteria of falsifiability, in that a hypothesis can always be modified ad hoc when falsified. This is not merely a feature of pseudoscience, but it is necessary for science to progress. Next Thagard reasons that since falsification is really the process of replacing a hypothesis with a better one, a theory is falsifiable if it can be replaced. This renders the demarcation between science and pseudoscience almost meaningless.
Thagard’s solution is to require something about the attitudes of the researchers to be a certain way. The two criteria for a study to be pseudoscientific are that a) the discipline is less progressive than the competing theories over long periods of time, and have unresolved issues regarding their work; yet b) instead of aiming to solve these issues, the community of practitioners, keeps attempting to selectively confirm their hypotheses, disregarding criticisms without attempting to refute them. This succeeds where Thagard found fault in Popper, namely that even when hypotheses are modified ad hoc to escape falsification, the repeated act of ad hoc modification makes a study pseudoscientific.

Does Cold Fusion Meet Theses Demarcation Standards?

Cold Fusion


Let us first examine how Popper would interpret cold fusion. In their 1989 paper, Fleischmann and Pons make no predictions or hypotheses, they merely show the results of their device. Right from the start, this seems like pseudoscience according to Popper. If there are no predictions, then there can be no prohibitive statements. Moreover, since the experiment was not able to be verified, it cannot be falsified. For a theory to be falsifiable, it must be able to be proven wrong. However this precludes it being able to be proven right. A generous interpretation of Popper would be that Fleischmann and Popper inherently predict repeatability as a part of their hypothesis. This implied prediction is that cold fusion is a reaction which can be repeated over and over because it follows the laws of physics. Under this interpretation, although cold fusion was shown not to work, it would not be considered pseudoscience.
How ever generously we interpret Fleischmann and Pons work, the same consideration will not prove helpful to the other cold fusion advocates in this category. It is reasonable to suspect that those people who are also believers of other pseudosciences likely do not have scientific beliefs about cold fusion. This is made clear by the way they are quick to make ad hoc explanations for why the experiments are not replicable. It appears that, for these people, there is no information that could convince them that cold fusion is unsuccessful. This view is textbook pseudoscience.
What about Andrea Rossi and the E-Cat? Would Popper consider this pseudoscience? The attitude of those affiliated with E-Cat, that we should worry about how it works after commercializing it, has an odour of pseudoscience about it. They make no real predictions or prohibitions, and thus are much like the original cold fusion advocates. However Popper would likely consider them pseudoscientists.


Knowing how Thagard regards Popper’s demarcation criteria, it is natural to anticipate some different interpretations. Again let us start by looking at the Fleischmann and Pons experiment. The study of cold fusion was virtually nonexistent before they published their experiment, and the two researchers have been quiet since the few years after they published. Thagard would not consider Fleischmann and Pons pseudoscientists because they do not meet his demarcation criteria.
Again, the cold fusion advocates since them are very different. They all match the criteria proposed by Thagard, especially the second. The first criterion is difficult to apply to cold fusion as the rest of the scientific community considers it to be impossible. The second criteria, however, describes these cold fusion advocates very well. They are unworried by the unrepeatable experiments and even go to the extreme of labeling the scientific establishment as pseudoscientists.



Popper would treat the LENR group differently than the cold fusion advocates. The difference between the two groups is that the one is planning genuine tests to falsify the reactions proposed by Widom-Larson. The prediction of certain subatomic particles, which are products of fusion, being present on the detector is indeed risky. By Poppers standards, LENR is science.

Thagard’s criteria are again difficult to apply to LENR. Since the experiments are still being planned, we cannot tell how Widom, Larson or Zawodny will react to a failed or successful experiment. When we consider that the Widom-Larson is an attempt to solve the issues involved with cold fusion, then LENR seems to avoid the second Thagard criterion. Since LENR is different than the cold fusion of old, then it can be regarded as being more progressive than the competing theory, and also avoid the first criterion. By this reasoning, LENR is not a pseudoscience according to Thagard.

Why should we worry about Cold Fusion Today

After the NASA funded experiments by Zawodny et. al. are completed, we will either find a changing energy market, one with plentiful inexpensive energy, or we will continue to live in a world where cold fusion is a dead end. Regardless of the success of the experiments, false cold fusion reactors remain a constant fraud risk for investors. In addition, pseudoscientific forms of cold fusion pose a risk to an incresingly scientifically illiterate public and their governments. Investing in the wrong kinds of new energy would not only cost money, but slow down progress on genuine green energies.


In summary, there are two parties in the cold fusion community. One, which I have referred to as cold fusion is pseudoscience, while LENR is scientific, even if turns out to be unsuccessful. This is reminiscent of the similarly non pseudoscientific Fleischmann and Pons experiments which were also unsuccessful.


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  12. Widom, A., & Larsen, L. (2006). Ultra low momentum neutron catalyzed nuclear reactions on metallic hydride surfaces. The European Physical Journal C-Particles and Fields, 46(1), 107-111.
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All Pictures and Videos used are take directly from the links to which they are attached.

Authored by Jordan Salisbury, last updated Feb. 27, 2013.