Criticism
Criticism of cold fusion claims generally take one of two forms: either pointing out the theoretical implausibility of the claims that fusion reactions have occurred in electrolysis set-ups or criticizing the excess heat measurements themselves as being spurious, erroneous, or due to poor methodology or controls.
Incompatibilities with known fusion reactions
There are many reasons why known fusion reactions are unlikely explanations for the excess heat and associated claims described above.
[text 9]
Repulsion forces
Because nuclei are all positively charged, they strongly repel one another.
[37] Normally, in the absence of a catalyst such as a
muon, very high kinetic energies are required to overcome this repulsion.
[144]Extrapolating from known fusion rates, 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.
[145]
In muon-catalyzed fusion there are more fusions because the presence of the muon causes deuterium nuclei to be 207 times closer than in ordinary deuterium gas.
[146] But deuterium nuclei inside a palladium lattice are further apart than in deuterium gas, and there should be fewer fusion reactions, not more.
[139]
Paneth and Peters in the 1920s already knew that palladium can absorb up to 900 times its own volume of hydrogen gas, storing it at several thousands of times the atmospheric pressure.
[147]This led them to believe that they could increase the nuclear fusion rate by simply loading palladium rods with hydrogen gas.
[147] Tandberg then tried the same experiment but used electrolysis to make palladium absorb more deuterium and force the deuterium further together inside the rods, thus anticipating the main elements of Fleischmann and Pons' experiment.
[147][18] They all hoped that pairs of hydrogen nuclei would fuse together to form helium nuclei, which at the time were very needed in Germany to fill
zeppelins, but no evidence of helium or of increased fusion rate was ever found.
[147]
This was also the belief of geologist Palmer, who convinced Steven Jones that the helium-3 occurring naturally in Earth perhaps came from fusion involving hydrogen isotopes inside catalysts like nickel and palladium.
[148]This led their team in 1986 to independently make the same experimental setup as Fleischmann and Pons (a palladium cathode submerged in heavy water, absorbing deuterium via electrolysis).
[149] Fleischmann and Pons had much the same belief,
[150] but they calculated the pressure to be of 1027atmospheres, when CF experiments only achieve a ratio of one to one, which only has between 10,000 and 20,000 atmospheres.
[text 10] John R. Huizengasays they had misinterpreted the
Nernst equation, leading them to believe that there was enough pressure to bring deuterons so close to each other that there would be spontaneous fusions.
[151]
Lack of expected reaction products
Conventional deuteron fusion is a two-step process,
[text 9] in which an unstable high energy intermediary is formed:
D + D →
4He * + 24
MeV
Experiments have observed only three decay pathways for this excited-state nucleus, with the branching ratio showing the probability that any given intermediate follows a particular pathway.
[text 9] The products formed via these decay pathways are:
4He* →
n +
3He + 3.3 MeV (
ratio=50%)
4He* →
p +
3H + 4.0 MeV (ratio=50%)
4He* → 4He +
γ + 24 MeV (ratio=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.
[37] This result is consistent with the predictions of the
Bohr model.
[text 11] If one watt (1 eV = 1.602 x 10−19 joule) of nuclear power were produced from deuteron fusion consistent with known branching ratios, the resulting neutron and tritium (3H) production would be easily measured.
[37][152] 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 both theoretically predicted and observed branching probabilities.
[text 9] 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.
[text 9]
The known rate of the decay process together with the inter-atomic spacing in a
metallic crystal makes heat transfer of the 24 MeV excess energy into the host metal lattice prior to the
intermediary's decay inexplicable in terms of conventional understandings of momentum and energy transfer,
[153]and even then we would see measurable levels of radiation.
[154] Also, experiments indicate that the ratios of deuterium fusion remain constant at different energies.
[155] In general, pressure and chemical environment only cause small changes to fusion ratios.
[155] An early explanation invoked the
Oppenheimer–Phillips process at low energies, but its magnitude was too small to explain the altered ratios.
[156]
Setup of experiments
Cold fusion setups utilize an input power source (to ostensibly provide
activation energy), a
platinum groupelectrode, a deuterium or hydrogen source, a calorimeter, and, at times, detectors to look for byproducts such as helium or neutrons. Critics have variously taken issue with each of these aspects and further assert that there has not yet been a consistent reproduction of claimed cold fusion results in either energy output or byproducts. Some cold fusion researchers who claim that they can consistently measure an excess heat effect have argued that the apparent lack of reproducibility might be attributable to a lack of quality control in the electrode metal or the amount of hydrogen or deuterium loaded in the system. Skeptics have further criticized what they describe as mistakes or errors of interpretation that cold fusion researchers have made in certain calorimetry analyses and energy budgets.
Reproducibility
In 1989, after Fleischmann and Pons had made their claims, many research groups tried to reproduce the Fleischmann-Pons experiment, without success. A few other research groups however reported successful reproductions of cold fusion during this time. In July 1989 an Indian group of
BARC (P. K. Iyengar and M. Srinivasan) and in October 1989 a team from USA (Bockris et al.) reported on creation of tritium. In December 1990 Professor Richard Oriani of Minnesota University reported excess heat.
[157][notes 4]
Groups that did report successes found that some of their cells were producing the effect where other cells that were built exactly the same and used the same materials were not producing the effect.
[158] Researchers that continued to work on the topic have claimed that over the years many successful replications have been made, but still have problems getting reliable replications.
[159] Reproducibility is one of the main principles of the scientific method, and its lack led most physicists to believe that the few positive reports could be attributed to experimental error.
[158][text 12] The DOE 2004 report said among its conclusions and recommendations:
"Ordinarily, new scientific discoveries are claimed to be consistent and reproducible; as a result, if the experiments are not complicated, the discovery can usually be confirmed or disproved in a few months. The claims of cold fusion, however, are unusual in that even the strongest proponents of cold fusion assert that the experiments, for unknown reasons, are not consistent and reproducible at the present time. (...) Internal inconsistencies and lack of predictability and reproducibility remain serious concerns. (...) The Panel recommends that the cold fusion research efforts in the area of heat production focus primarily on confirming or disproving reports of excess heat."
[88]
As David Goodstein explains,
[30]proponents say that the positive results with excess heat and neutron emission are enough to prove that the phenomenon was real, that negative results didn't count because they could be caused by flaws in the setup, and that you can't prove an idea false by simply having a negative replication. This is a reversal of
Karl Popper's
falsifiability, which says that you can't prove ideas true, never mind how many times your experiment is successful, and that a single negative experiment can prove your idea wrong.
[30] Most scientists follow Popper's idea of falsifiability and discarded cold fusion as soon as they weren't able to replicate the effect in their own laboratory. Goodstein notes that he was impressed by a "particularly elegant, well designed experiment" and warns that by ignoring such results "science is not functioning normally."
[30]
Loading ratio
Michael McKubre working on deuterium gas-based cold fusion cell used by
SRI International.
Cold fusion researchers (
McKubre since 1994,
[159] ENEA in 2011
[86]) have posited that a cell that was loaded with a deuterium/palladium ratio lower than 100% (or 1:1) would never produce excess heat.
[159] Storms added in 1996 that the load ratio has to be maintained during many hours of electrolysis before the effects appear.
[159] Since most of the negative replications in 1989–1990 didn't report their ratios, this has been proposed as an explanation for failed replications.
[159]This loading ratio is tricky to obtain, and some batches of palladium never reach it because the pressure causes cracks in the palladium, allowing the deuterium to escape.
[159] Unfortunately, Fleischmann and Pons never disclosed the deuterium/palladium ratio achieved in their cells,
[160] there are no longer any batches of the palladium used by Fleischmann and Pons (because the supplier uses now a different manufacturing process),
[159] and researchers still have problems finding batches of palladium that achieve heat production reliably.
[159]
Misinterpretation of data
Some research groups initially reported that they had replicated the Fleischmann and Pons results but later retracted their reports and offered an alternative explanation for their original positive results. A group at
Georgia Tech found problems with their neutron detector, and
Texas A&M discovered bad wiring in their thermometers.
[161]These retractions, combined with negative results from some famous laboratories,
[6] led most scientists to conclude, as early as 1989, that no positive result should be attributed to cold fusion.
[161][162]
Calorimetry errors
The calculation of excess heat in electrochemical cells involves certain assumptions.
[163] Errors in these assumptions have been offered as non-nuclear explanations for excess heat.
One assumption made by Fleischmann and Pons is that the efficiency of electrolysis is nearly 100%, meaning 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.
[24] This assumption gives the amount of energy expended converting liquid D2O into gaseous D2 and O2.
[164] The efficiency of electrolysis is 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.
[165][166][167]
Another assumption is that heat loss from the calorimeter maintains the same relationship with measured temperature as found when calibrating the calorimeter.
[24] 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.
[168] This can happen, for example, if fluid circulation within the cell becomes significantly altered.
[169][170] Recombination of hydrogen and oxygen within the calorimeter would also alter the heat distribution and invalidate the calibration.
[167][171][172]
According to John R. Huizenga, who co-chaired the DOE 1989 panel, if unexplained excess heat is not accompanied by a commensurate amount of nuclear products, then it must not be interpreted as nuclear in origin, but as a measuring error.
[173]
Initial lack of control experiments
Control experiments are part of the scientific method to prove that the measured effects do not happen by chance, but are direct results of the experiment. One of the points of criticism of Fleischmann and Pons was the lack of control experiments
Cold fusion is a hypothetical type of nuclear fusion reaction that would occur at, or near, room temperature, compared with temperatures in the millions of degrees that are required for "hot" fusion, which takes place naturally within stars.
Recent technological breakthroughs had resulted in the development of suitcase-sized LENR reactors that can be mass produced. One such LENR generator located in each village and powering a local village-level micro-grid can work wonders.
A research centre cum manufacturing base for these reactors have been set up in Baoding in eastern China and at least two companies have announced likely market release of multi-KW LENR reactors during 2015.
In other world something similar to Tony Stark's Arc Reactor
It will be a revolutionary . Think about aircraft with small reactor ...
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