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  Why is cold fusion considered bogus?

+ 11 like - 0 dislike
45331 views

Cold fusion is being mentioned a lot lately because of some new setup that apparently works. This is an unverified claim.

See for example:

While we should give the scientific community time to evaluate the set up and eventually replicate the results, there is undoubtedly some skepticism that cold fusion would work at all, because the claim is quite extraordinary.

In the past, after Fleischmann and Pons announced their cold fusion results, in perfectly good faith, they were proven wrong by subsequent experiments.

What are the experimental realities that make Fleischmann and Pons style cold fusions experiments easy to get wrong?

Would the same risks apply to this new set up?

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Sklivvz
asked Jan 24, 2011 in Experimental Physics by anonymous [ no revision ]
retagged Mar 24, 2014 by dimension10
Most voted comments show all comments
@Jeff: It makes no sense theoretically, and the experimental evidence is scant at best.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Jerry Schirmer
Why the close vote? I ran this through meta and it seems to me the question is producing objective answers?

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Sklivvz
@Sklivvz: I think its a nice question belonging to the site, too. Greets

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Robert Filter
The fact that cold fusion is a pile of steaming **** isn't justification for closing discussion on why it's a pile of steaming ****.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ben Crowell
Also keep in mind, patents for original ideas, not working anything. The US Patent Office gave out thousands of patents for Perpetual Motion Machines too. A patent means nothing in this context.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Mooing Duck
Most recent comments show all comments
@dmckee,@nibot It's 403-ing for me too now. I know the "journal" is not an authoritative publication. They admit they set it up because they couldn't get published (they blamed the CF stigma). In any case the paper did not include the experimental setup (they only say they used a calorimeter, basically), but the setup is shown in the patent application. Yep, it sounds like bogus to me too.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Sklivvz
"apparently works" "perfectly good faith" You are being way too subjective. The reason most physicists are very skeptical is because it makes no sense theoretically.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user pho

13 Answers

+ 12 like - 0 dislike

This was beautifully answered theoretically right away at the 1989 APS session in NY, I think by Koonin. Theoretically, for any sort of fusion one needs to overcome the Coulomb repulsion of the relevant nuclei, on the order of MeV in order to allow the nuclei to get close enough for their wave functions to overlap and fuse. Because of the phenomenom of quantum mechanical tunnelling, this can be reduced to tens to hundreds of kev. So temperatures of >> 10^5 K, or cold muons (which outweigh electrons by 200x) are required to reduce the internuclear distance (as in muon catalyzed cold fusion, a real phenomenon), or some other special mechanism is required to allow this close approach.

However, for any sort of chemically catalyzed fusion, i.e. via the valence electrons, to take place, the binding energy of the two H atoms to the catalyst would have to be so high, that the particular configuration of the low energy valence electrons, etc. would necessarily be entirely irrelevant to the problem, i.e. whatever their arrangement they could not possibly catalyze the fusionable nuclei to approach close enough to fuse. So no clever packing arrangement, quasiparticles, special adsorbtion, special crystal lattice structures, etc. could ever alter this conclusion. Whatever was happening at such low energy scales would appear as a kind of irrelevant fluff compared to the energy scale of the internuclear distance necessary for fusion.

Therefore valence electron catalyzed cold fusion would violate the fundamental laws of quantum mechanics, nuclear physics, etc. Leggett and Baym also published an argument like this around the same time (summarized for free here). Koonin and Nauenberg published an accurate calculation here, showing that if the mass of the electron were 5-10 times larger than it really is, chemically calalyzed fusion could work. Note however, that the reaction rate depends on the electron mass very, very strongly, so that this remains impossible in our universe.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user sigoldberg1
answered Jan 25, 2011 by sigoldberg1 (180 points) [ no revision ]
10 kev works because of tunneling.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user sigoldberg1
Is there some confusion between Coulomb barrier and binding energy here?

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user anna v
@Anna, the coulomb barrier is the minimum energy the cores have to surpass to "fuse". This is in terms of a chemical reaction the energy of activation.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Georg
Julian Schwinger tried to submit papers on cold fusion but they were rejected by the referees. They might have made interesting reading since Julian was probably Robert Oppenheimer's brightest student.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Gordon
Since this came up in the first page again, I will add the comment that I also make in my answer: crystals may behave differently than thermodynamic and quantum mechanical intuition in bulk tells us. There might be a way that a "virtual electron" could propagate down the crystal lattice that has the higher mass necessary that you mention. The problem with cold fusion is not that it is theoretically impossible, but that it has not been demonstrated consistently in experiments. Otherwise there would be machines for sale, the way there are solar panels. When the machine exists, the theory comes.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user anna v
-1 this answer is short-sighted. Experimental data is to be evaluated by placing theoretical prejudice aside. There are sound theoretical arguments for KeV deuterons in cold fusion, but even lacking this evidence, the argument "high energy requires high temperature" is just false.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ron Maimon
" So no clever packing arrangement, quasiparticles, special adsorbtion, special crystal lattice structures, etc. could ever alter this conclusion.". Perfect, but it all relies on the fact that the concept of valence electrons is an approximation that is valid in a widely set of chemical compounds under adiabatic circumstances. If something in the multi-electron system would make the description invalid, this conclusion would be as well.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user lurscher
I remember that a few years ago the Quasicrystals were impossible by Theory and that, the now 2011 Nobel laureate, Shechtman suffered a lot of prejudice by preconceived ideas of 'impossibility' (He reported that in a video interview). Theories are provisional and are to be replaced by other more perfect. I will wait and I hope it's true for the benefit of all of us. Usually theories are provisional and follows the experiments and not the contrary.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Helder Velez
@annav: I don't think a lack of consistent demonstration in experiments says much about the reality of a purported experimental phenomenon. Some things are hard to pin down. It took years to figure out how to make reliable transistors, for example.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Eric Walker
@sigoldberg1: You're approaching the question of cold fusion from a theoretical angle -- basically saying that theory doesn't allow it. I think it's very good to point this out. But at their heart, the central claims relating to cold fusion are empirical ones at the present time. For this reason, it seems to me that criticisms must address the purported experimental phenomena and that arguing from theory is getting things backwards; to agree with you, we must assume that present theory is ironclad in this area.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Eric Walker
@EricWalker I agree, and that is why I keep an open mind to beconvinced once experiments become convincing.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user anna v
+ 10 like - 0 dislike

The treatment of Pons/Fleischmann is, by far, the worst scandal in modern science. It is probably worse than Galileo. Their claims were true, were reproduced immediately in several labs (sporadically, many labs failed too), and good research continues to this day, without funding and without theory.

Experimental History

Their claim is not completely new. It goes back to the 1920's, when Paneth and Peters reported Helium production in Pd heavy water electrolysis. Paneth and Peters' claims were dismissed for essentially the same reason that Pons and Fleischmann's were, the theorists' imaginations were too stunted to think up a mechanism that could bridge the gap between chemical energies and nuclear energies. In the 1950s, there was a Soviet scientist who also claimed that Pd heavy water electrolysis leads to nuclear anomalies. That claim was also dismissed by the Soviet scientific establishment, but his career was rehabilitated somewhat after Americans reproduced the effect in 1989.

Many people (i.e. graduate students) who worked with Pd/deuterium system noticed anomalies in the system for decades, and it was folklore in the chemistry community that deuterated Palladium acts up, while Hydrogenated Pd does not. Pons and Fleischmann decided to get serious about the anomalies, and did extremely careful calorimetry on the system for many years, until they were certain they had a reproducible effect for which chemistry could be safely excluded. Then they held their press conference, and chaos.

Part of the problem is that once they claimed fusion, people insisted that the fusion should emit neutrons, just as hot fusion does. This is impossible, because, considering the energy released, the number of neutrons would have cooked Pons and Fleischmann. Then nuclear physicists demanded that they measure nuclear effects, and they tried to do this, but their nuclear measurements were riddled with errors, and it is possible that they fudged a plot that they showed at a conference (although considering Fleischmann's impeccable scientific integrity, I find it more plausible that they made an honest mistake). It is important to note that their published paper contains only calorimetry data, and no nuclear data of which they were unsure.

Some people speculated that the effect can be explained by chemistry, or by insufficient stirring, or by storing electrical energy for later release. These claims are all idiotic. The effect is not small, the only reason it requires instruments to detect is because Pons and Fleischmann deliberately used a tiny Pd wire as a cathode. When they used a bigger Pd plate, the thing melted the table, and blew a hole in the concrete floor below. There just is no source of chemical energy, nor a battery, which can store energy chemically at more than about 1eV per atom. Other people noticed similar runaway explosions too.

Aside from the explosion, there is possible heat from recombination, which has often been emphasized by critics. The electrodes separate H2 from O2, and if the two mix together and the hydrogen burns, you will see excess heat. To control this, groups used infrared cameras to locate the heat source at the cathode, rather than the water where bubbles of gas can mix. They also separted the anode and cathode. But most definitively, in 1994, Pons and Fleischman demonstrated heat after death in 1994, where they cycle the temperature in the anomalously heating cell up, then shut down the current entirely. The cell continues to produce heat for hours with no current, no oxygen, no hydrogen, and many times more heat than you can store in the cathode by any chemical means.

The effect is very sensitive to the metallurgy of the Palladium, and Pons and Fleischmann couldn't reproduce the finicky effect on demand once they ran out of the good palladium. The experiment sometimes takes weeks, and many people just didn't have patience. Still, the effect was reproduced immediately in a handful of places. MIT ran an infamous reproduction that noticed excess heat production, and were going to press with a reproduction. Then they realized that this effect was going to be labelled bogus, and they cut off their graph to show no excess heat. One of the graduate students who was involved in this experiment, Eugene Mallove, was so outraged that he quit his position and became a cold fusion promoter.

Several groups published reproductions. These groups were attacked in the most unscientific of ways. Several groups, Bocris at texas, but also reputable researchers at Bhabha institute and Los Alamos, reported low levels of tritium production in the system. Since tritium is radioactive, it has a clear signature, it can't be mistaken for anything else. Since it is very expensive and is ordinarily produced in nuclear reactors, the only way such a signal could be seen is if it was deliberately faked by spiking the heavy water with tritium. Bocris was accused of doing just this--- spiking his cells with tritium, so confident were the deniers that he had committed fraud. Despite the intense pressure, he never retracted his claim. Another colleague at Texas who claimed tritium, Wolf, did retract the claim when he saw what was happening to Bocris, and never spoke in support of cold fusion again. Bocris was investigated for scientific misconduct and exonerated. No plausible way he could obtain tritium (other than cold fusion) was ever found. The tritium observations would require all the researchers who observed tritium to be engaged in deliberate fraud. It is impossible to misidentify tritium.

Two extermely well respected theorists, Julian Schwinger (emeritus UCLA) and Peter Hagelstein at MIT, were convinced that the effect was real. Schwinger was not allowed to publish in the field, and Hagelstein, who was tenured, had all his funding cut and was moved into a closet.

In the early 90's, without any official funding, McKubre quantitated Helium production to correlate with the excess heat. Low levels of ordinary fusion are seen to happen in the system. The SPAWAR group in the U.S. Navy reproduced the effect in co-deposition experiments, where they plate Pd onto a surface in the presence of heavy water. Their experiments mostly detect nuclear products, because the plated surface is so small, but the effects are 100% reproducible. More recently, the navy presented evidence of sporadic high-energy neutrons coming from the co-deposition system.

In Japan, Mizuno noticed new elements being produced in the Pd system with abnormal isotope ratios and atomic number near Pd (this was also detected by Wolf, as reported by Eugene Mallove, but Wolf would not publish after the tritium fiasco). Abnormal isotope ratios cannot be fraud, because such materials are so difficult to make. In Japan, Arata reproduced the effect by using gas-loading of deuterium into Pd, which has no heat source, so there is no calorimetry error to blame things on. This was a foolproof version of Pons' and Fleischmann's "heat after death" experiments, and it also rules out calorimetry/recombination error entirely. The effect has been reproduced many hundreds of times, in far away labs with no mutual interests, and everybody should be certain by now that it is real. I am ashamed of myself, in that I couldn't bring myself to trust the experimental data until I came up with a reasonable theoretical story to explain it.

Focardi/Rossi claims are more dubious. Their effect is in Nickel/Hydrogen, which has some reported energy anomalies too, but not with the same level of confidence. In terms of theoretical craziness, Nickel Hydrogen fusion is to Palladium Deuterium fusion as Palladium Deuterium fusion is to standard hot fusion. The cold fusion community is taking a wait-and-see attitude, but I think consensus is that the device is not likely to work. In his demonstrations, Rossi measured heat production using steam, not water, and by understating the water-content of the steam, you can inflate the energy output by the latent energy of vaporization, which is huge. For me, it is most suspicious that his claimed transmutation products were analyzed and have natural isotope ratios. It is possible that his machine works, and it is possible that it does not produce any excess energy at all, we will know soon enough. What is impossible is that there are no nuclear effects in Pd/deuterium.

Here is an update regarding the e-cat, which, as people expected, is a sophisticated scam: Is the E-cat for real?.

Theoretical work

One major difficulty for acceptance of the effect is that theoretical work in this field is not sound. There are several theories, each of which are more or less preposterous. The central difficulties are overcoming the Coulomb barrier somehow, and making energy without nuclear reaction byproducts:

  • Hydrinos/little hydrogen: this theory states that the electron in Hydrogen can find a closer orbit than the ground state, and spends some times close to the nucleus. This requires that quantum mechanics is wrong, or that there is some new electron/proton force which has been missed, and somehow does not alter the ground state energy, but is capable of sucking the electron into the proton every once in a while.
  • Bose-Einstein condensed deuterons/alphas: this idea is that the cross section for fusion is enhanced by identical-particle effects, since deuterons and alphas are both bosons. In theory, you can enhance reactions by having a coherent source of bosons all go through the same reaction to a coherent superposition. This theory fails both because the temperature is too high for coherence between deuterons, and because when it is implemented in specific cold fusion papers, the deuterons are treated as non-interacting particles in a product state, so that the amplitude for being at the same point is big. But this is ignoring the whole difficulty, because the electrostatic repulsion leads the wavefunction to be entangled, with little probability of any two deuterons getting to the same point.
  • Lattice enhancement mechanisms: This was the focus of Schwinger and Hagelstein, neither of whom claimed to have solved the problem. The problem with such theories is only that the effects have to be collective over thousands of atoms to explain taking eV energies into KeV energies, and it is thermodynamically difficult to imagine how you can take such entropic energy into such an entropically unfavorable place as a single particle.
  • Weak Force Neutron production: The Widom Larson theory claims that it is possible for a proton and an electron to do inverse beta decay on the surface of a metal, where there are large local electric fields. This is preposterous, because of the MeV difference in proton and neutron mass. It requires millions of volts to accelerate an electron to enough energy to be able to do an inverse beta-decay, and such energies are not available on the surface of a metal. Further, this theory will predict transmutations of plus/minus one mass unit predominanatly, which is not observed, and does not explain how a deuteron can absorb an electron.

The following lists are bogus theories I speculated would work, other people come up with these too every once in a while:

  • sporadic atmospheric muon capture: The idea there is that muons are captured by the metal, and lead to fusion. This doesn't work, just because there are not enough muons, the deuterons are separated from each other in the lattice, and if the muon is captured by a Pd nucleus, it's wasted.
  • tunneling with weird many-body enhancement: the idea is that the tunneling amplitude is always estimated, not calculated, and this is an impossible-to-solve many electron/many nucleon system, so perhaps the tunneling amplitude is just off by many orders of magnitude. This doesn't work, because there is a way of giving a lower bound to tunneling amplitudes which excludes any appreciable fusion reaction by tunneling. To do this, you exploit the fact that tunneling is a ground state property, and the deuterons which are imagined to tunnel are bosons, and their imaginary time ground state has no nodes. The electrons have nodes, since they are fermions, and at high energies, but when the electron states are all fully occupied, they might as well be a vacuum, with structure only near the Fermi surface (this follows from the particle-hole symmetric approximate description of the Fermi liquid). There were rigorous upper bounds on the tunneling probability for deuterons in a metal that claimed to prove cold fusion is impossible.

The previous failures leads one to expect that the effect is out of equilibrium, and involves highly excited atoms.

My Personal Theory

To bridge the gap between the scale of chemistry at eVs and of the nuclei at MeVs, one should take note of the fact that there are K-shell electrons orbiting very close to the nucleus at KeV energies. The K-shell electron of Pd has a 20KeV ionization energy, and if you have a K-shell hole in one Pd atom, it stores an amount of energy non-entropically in an amount sufficient to lead to deuteron fusion. While this energy is large, it is not large enough to knock a Palladium atom out of its lattice position, so it cannot dump its energy by locally breaking the lattice. The reason is that the Pd nucleus requires more than the 20KeV ionization energy to be knocked out of position without it's core, and you can't conspiratorially transfer the hole energy to the entire core in one step, it's phase-space impossible.

Such K-shell holes usually decay by X-rays, but this is an electromagnetic process which is suppressed by powers of v/c when the electron is nonrelativistic, as it is even in the K-shell. This is a well known effect--- it's the same reason that atomic spectral lines are narrow. Emitting a photon takes many orbits because of the mismatch in scale between the photon's wavelength and the size of the orbit. This is ultimately because the orbit is nonrelativistic. Because the emission takes so long, the spectral lines are sharply defined and narrow, and the emission is dominated by the matrix elements of the dipole moment of the atomic state between stationary states.

Other observed ways for K-shells to lose their energy is to kick out an outer shell electron from a neighboring atom. This process is electrostatic, and nonrelativistic, so it is not suppressed by 1/c factors. It is only suppressed by the smallness of the charge on the electron and the distance between electrons on neighboring atoms. There is a significant fraction of decays in K-holes in Pd in this channel.

In a metal with protons or deuterons, a K-shell hole should be able to also kick its energy into a proton or deutrons by electrostatic forces. The matrix element is exactly the same as for kicking an electron, but the density of states is 30-50 times bigger (depending on whether it's a proton or a deuteron) due to the heavier mass. The proton, unlike a Pd nucleus, will leave its lattice site under such a transfer. So, considering that the cross section for a K-shell hole to kick an electron is not small, I feel safe to conclude that the proton-kicking process is the dominant decay mechanism for K-holes.

These deuterons have exactly the same energy as the K-shell hole, which means that their classical turning point when approaching a Pd nucleus is exactly the same distance from the nucleus electrostatically as the K-shell is wide, about 100 fermis. These holes can then excite another electron coherently, and travel many steps in the lattice before decaying by X-ray to the ground state. These hole-deuteron states make bands of several KeV width at energies around 20KeV, and these bands are full of classical turning points at 100fermis from a Pd nucleus.

Now suppose that two of these accelerated deuterons happen to come close to the same Pd nucleus. This can easily produce a fusion event at the turning point, the deuterons have around 20KeV after all, and the fusion rates at 20 KeV in beams is not that small, let alone in cases where the wavefunction is concentrated near a nucleus with a classical turning point (where the wavefunction is enhanced).

This fusion does not necessarily happen in the usual hot-fusion way, since it is very close to a Pd nucleus. Let us suppose that the fusion transfers the excess energy/momentum to a nearby charged particle electrostatically, the obvious candidate being one of the protons Pd nucleus. Then the alpha particle and whatever it transferred its energy to are moving with 24MeV of energy together, and they go through the metal, ionizing Pd atoms. Energetically, they can make up to 1000 K-shell holes, all within a millimeter, since the penetration depth is so tiny. The true number is more likely a hundred or a few hundred, since all levels are excited during the Bethe process of charged particle ionization. These holes are then banded with deuterons, so they accelerate new deuterons, and this can easily lead to a chain reaction. I believe this explains the cold-fusion.

There are two problems with this idea:

  1. The cross section for fusion at 20 KeV is not that huge, and it does not lead to a chain reaction by itself through the usual hot-fusion channels. The multiplication factor is around .001 from beam fusion on deuterated Pd, which has a 1 in 100,000 success rate, not 1 in 100, at 20KeV.
  2. The actual observed reaction produces an alpha particle without an emitted neutron or proton nearly all of the time. This is a 1-in-a-million event in hot fusion.

I think that both problems are related to the fact that the reaction is happening inside a dense metal. The first problem is not present if two deuterons are banded and both turning around near a nucleus, the result is like a directed collision of two 20KeV beams with a very good focusing device (the nucleus) to concentrate the scattering wavefunction.

The fusion of deuterons always happens through unstable intermediate states, and the cross section to alpha particle is only small because of the same non-relativistic issue. To get an alpha, you need to emit a gamma-ray photon, and emissions of photons are suppressed by 1/c factors. When there is a nucleus nearby, it can be kicked electrostatically, and this process is easier than kicking out a photon, because it is nonrelativistic (the same holds for an electron, but with much smaller cross section due to the smaller charge, and there is no reason to suspect concentration of wavefunction around electron density, as there is for a nucleus).

The time-scale for kicking a nucleus is the lifetime of the two-deuteron resonance, which is not very long, in terms of distance, it is about 100 fermis, this is about the same size as the inner shell. If the deuterons are kicking about at random, this coincidence is not significant, but if the deuteron-hole excitations are banded, it is plausible that nearly all the energetic deuteron-deuteron collisions take place very close to a nucleus, as explained above.

There are conservation laws broken when a nucleus is nearby. The nucleus breaks parity, so it might open up a fusion channel, by allowing deuteron pairs to decay to an alpha from a parity odd state. Such a transition would never be observed in a dilute beam fusion, because these fusions happen far away from anything else. This hypothesis is not excluded by alpha particle spectroscopy (there are a lot of relevant levels of different parities), but it is not predicted either.

But since something ha

answered Aug 18, 2011 by Ron Maimon (7,730 points) [ no revision ]
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@Ron: please post a link to your write-up when a draft is available.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Eric Walker
@EricWalker: I'll try to write something up over thanksgiving--- I am doing some bioinformatics work, and this is very time consuming, as it involves a lot of programming. I also am having a hard time finding good product data for 20MeV electron/photon on Pd, although I found the general patterns of ejections, I don't have quantitative fragmentation ratios. This is a little annoying, there's plenty of data, it's just hard to search through it. It's hard to predict fragmentation ratios theoretically.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
@RonMaimon: Two interesting comments on your proposal: bit.ly/ThCPfj and bit.ly/SgBOqi.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Eric Walker
@EricWalker: Spaandonk has a wrong intuition: The energy deposited by a 24 MeV alpha is not eaten up quickly by valence electrons, it is preferentially deposited in K-shells (this is described by Bethe formula ionization). The result is not "glue", charged particles of this energy go through a mm of metal before stopping, and leave behind a mm of hundreds of K-shell ionized atoms. This K-shell is mixed with D in the metal, and makes a band. The 20KeV K-shell can't knock out a Pd nucleus, because such a nucleus would be fully ionized, and this is more energy than K-shell ionization only.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
... both of these things were the first things I checked years ago, and I found the multiplication factor required from dilute fusion experiments in beams, and it was a few orders of magnitude off (like 2 or 3, not 10). This was not discouraging, because other theories are off by 10 orders of magnitude, and also the lack of neutrons means that something else is happening. The double-d reaction requires that the K-shell band conducts the deuterons to bumps on the surface, where they are concentrated sufficiently to allow fusion. The Ni-H (if it exists) requires the d-p reaction to occur.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
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@Ron - No I have not been 'monumentally wrong' on anything relating to this yet. You however have produced scads of erroneous information and you resort to character assasination (as you just did yet again) instead of reasoned discussion. If you think I am incorrect, prove it. Specifically state an error and explain why it is with more than just hand waving. Just one...that's all.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Kirk Shanahan
@KirkShanahan: Ok--- take the dozens of tritium observations. They are just plain impossible without fraud, as you can't make tritium chemically, and you can't fake it's detection (it's radioactive with a clear signature). Bocris, Wolf, Bhabha, and Los Alamos detected tritium. End of story. Done. Nothing else needed. Dude, you are really pissing me off. By laughing off the evidence, the tritium, and making up bunk explanations for the rest, you make it impossible to have a rational discussion. I will no longer try, I have things to do.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
+ 6 like - 0 dislike

There are a few reasons.

  1. There was never any clear reason why electrifying palladium should create pressures sufficient to ignite a fusion reaction. Without a mechanism, this seems to be the most ridiculously radical and sensational conclusion possible, even if the calorimetry says that electrified palladium creates net energy somehow. Why not start with simpler explanations than saying that it's fusion?

  2. the only evidence anyone has ever offered was calorimetry of a small-scale experiment. But calorimetry is a complicated thing--you have to model the insulation of the system just right, and you have to measure the heat inputs for the system correctly, and so on.

  3. No fusion products have ever been observed--fusion would be plausible if they were able to show that the reactions produced some helium-3 or lithium or whatever.

  4. The setup they describe in these experiments seems quite simple--just submerge some palladium underwater, and run electricity through it. If this really produces a fusion reaction, why not just scale it up and build a reactor? I'm sure if they could power a building with a palladium fusion reactor (or even just a light bulb), every critic would instantly shut up and get behind them. And they never seem to explain why they don't just do this. I'm never going to believe in your revolutionary new form of cheap energy unless you just start producing cheap energy with it (or at least explain why you can't).

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Jerry Schirmer
answered Jan 24, 2011 by jerryschirmer (250 points) [ no revision ]
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Iwamura 2000 Pd/LiOD+D2O F,Al,Si,S,Cl,C,Ca,Ti,Cr,Mn,Fe,Co --- Iwamura 1998 Pd/LiOD+D2O Ti, Cu, Fe (isotope change) --- Mizuno 1996 Pd/LiOH+D2O Pt,Pb --- Rolison 1991 Pd/LiSO4+D2O,H2) Rh,Ag ----- really consistent right... the lack of consistency really points to contamination due to various materials from different sources. And recall that Rolison attributed their elements to bulk Pd impurities concentrating on the surface

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Kirk Shanahan
@KirkShanahan: The Ag, Ru transmutations are significant because they are detected radiologically by Wolf using gamma emissions. The Bocris results were many times background, and are done in an independent lab, who knows what Inyengar did exactly. I rely on Iwamura data, because it focused on large transmutations, I don't know anything about Rolison. I only know what theory predicts, it predicts fragmentation of protons, alphas, or ejection of highly stable nuclei (full shells) as appropriate for 20MeV excitation of a Pd nucleus, and this produces Pd atoms reduced by 4,8,12,16 mass units.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ron Maimon
@KirkShanahan: I don't like the way you have of comparing careful experiments to careless work, you can discredit anything by comparing to the worst results. I agree that there are papers that are not stellar in the field, as in any field, but one has to look for the most carefully analyzed data and come to grips with it, and not reject it because someone else did a crappy experiment too.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ron Maimon
I am not disputing that researchers find 'new' elements, I am disputing their source. There's no need to assume nuc. rxs., migrating contamination solves the problem nicely, and has been demonstrated elsewhere (Little and Rolison for ex.). Which Bockris results? The 10X He you noted in the other thread? See my answer there, 10X is not real. Actually the same. As far as I have seen, there are no careful experiments that end up claiming nuc. rxs. The careful ones find it is contamination.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Kirk Shanahan
@RonMaimon: I've started a chat room to continue this line of questioning -- I'm not sure if you will have gotten my ping.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Eric Walker
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@KirkShanahan: You are doing foolish politics. You can't get radioactive elements (detected by gamma) from a nonradioactive cathode. No segregation can produce tritium, and yes, the codeposition He levels have been as high as 10 times atmospheric. The fusion does not require new physics, I explained how it happens, it is required by existing physics, and one can predict it happens regularly in any sufficiently heavy metal capable of deuteration, and there is no way to avoid it. The experiments are excellent for their funding levels, and your pseudo-explanations of the results are pathetic.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ron Maimon
Nice fail Ron. I ask for a detailed, reasoned outline of just one of my 'errors' and I get the above... P.S. I don't believe your theory. P.P.S. I don't believe 10X atmospheric - cite your ref. please. Oh, and P.P.P.S. leaks will in fact lead to He increasing over time.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Kirk Shanahan
+ 6 like - 0 dislike

Pons and Fleischmann originally reported in 1989 that their chemical cells had produced excess heat, neutrons, and tritium. Their interpretation was that deuterium nuclei were fusing to produce 4He. The branching ratios in this process are known: 50% n+3He, 50% p+3H, and 10^-6 4He+gamma. If the claimed excess heat had been produced by fusion, then the experimenters would have been killed by the neutrons coming from the 50% of the decays that proceeded by neutron emission. Neutron detectors are infamous among nuclear physicists for being difficult to use, and for having a tendency to produce spurious signals. Even if all the neutron counts claimed by Pons and Fleischmann had been real, the observed flux of neutrons would have been many orders of magnitude too small in relation to the amount of excess heat claimed. Subsequent measurements by nuclear physicists using state-of-the-art neutron detection techniques demonstrated that no neutrons above background level are produced by chemical cells of the type used by Pons and Fleischmann.[Gai 1989] There has also been no plausible evidence for production of 3He, 3H, or gamma rays, all of which would have been copiously produced in d-d fusion reactions that produced measurable amounts of energy through nuclear reactions.

As of 2010, the consensus among scientists is that cold fusion was an example of pathological science. However, a few true believers continue to do experiments and make claims of positive results. A 2010 review by a prominent believer[Storms 2010] says that "Many people feel that the correlation between heat and helium is the strongest evidence for cold fusion." The trouble is that heat is produced by chemical reactions in any case, and the levels of helium claimed are not high enough to show a convincing excess relative to background. If these claims were correct, they would also require a fundamental rewriting of the laws of physics. They would require that the branching ratio in d-d fusion be drastically altered by the chemical environment, but this is impossible because in a nuclear reaction, the electrons are mere spectators. In order to conserve energy and momentum, d-d fusion also requires the emission of two particles in the final state. To get around the nonexistence of the second particle, cold fusion enthusiasts suppose that energy from the reaction is transmitted to the electronic lattice. No known mechanism exists by which such transmission could occur. As the experimental and theoretical constraints have gotten tighter, the believers have responded by coming up with crazier pseudoscience, insluding the production of nuclei with atomic number 126 and transmutation of the elements by plants and bacteria.[Storms 2010]

In summary, claims of cold fusion cannot be correct unless they overturn firmly established knowledge of nuclear physics. This would be an extraordinary claim, and it would require extraordinary proof. After two decades, no such extraordinary proof has emerged.

Gai et al., "Upper limits on neutron and gamma-ray emission from cold fusion", Nature 340 (1989) 29–34.

Storms, "Status of cold fusion (2010)", Naturwissenschaften (online) 97 (10): 861–881

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ben Crowell
answered Aug 18, 2011 by Ben Crowell (1,070 points) [ no revision ]
Your answer is pretty levelheaded, but I recommend that you look at SPAWAR experiments and Arata experiments. SPAWAR show conclusively that there are energetic charged particles, while Arata shows that there is heat and helium correlated. The Helium levels in several Pons/Fleischmann type experiments are well above background, and tritium production is completely inexplicable. As for transfer of nuclear energy to the lattice, that is a mystery which could be solved in principle by a three-body deuteron-deuteron-nucleus interaction, so it does not rule out the process.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
The Gai paper you cite: nature.com/nature/journal/v340/n6228/abs/340029a0.html doesn't do calorimetry. How would they possibly know when the reaction was happening, if at all? Maybe they ran duds. Maybe they ran at too low a loading. It's a junk paper, and it should never have been published.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
@Ron Maimon: We obviously disagree completely about what's garbage science and what's not. "Maybe they ran duds." Of course they ran duds. Cold fusion doesn't exist, so all cold fusion cells are duds.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ben Crowell
If they couldn't reproduce the effect, what value does it add to mesure background neutron counts? They just wanted to add their voices to the "me too" list of failed reproductions. I showed my mild mannered father papers like these, and I told him, "You know, people like that should be fired". He said "people like that should be shot."

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
For the humor impaired, the true anecdote above is a joke, not a threat.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
+ 6 like - 1 dislike

The Fleischmann and Pons device relied on calorimetry (measuring the energy balance in terms of heat) maintained over multiple day time spans to ascertain that something unexpected was happening in the cell.

This is experimentally tricky, as it requires high precision temperature measurements to be maintained against a consistent reference, and relies on an understanding of how the calorimeter may or may not be losing heat though unmonitored channels.

In short a large heat loss is being subtracted from a large heat input, and both measurements have some uncertainty. That's a warning sign in any experiment, but not a death knell if the uncertainty can be quantified with sufficient accuracy.

The situation is complicated by the time dependent heat loss that Fleischmann and Pons reported. If real, that would indicate some unexpected process at work, though we have no way of know a priori if that is fusion or some energy storage-and-release mechanism.

It seem to have been lack of consistency in reports of energy gain or neutrons that swung opinion against any fusion actually happening in the F&P cell.


BTW--People who kept at it for a few years after the consensus turned against were engaged in good science. There was always some small possibility that the process was dependent on some un-measured and un-controlled factor. To find out, one would need to accumulate a non-trivial set of working cells and then investigate how they were different from non-working cells.

But as the man said "If at first you don't succeed, try, try again. Then quit. There's no use being a damn fool about it." Sooner or later you just have to give up.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user dmckee
answered Jan 24, 2011 by dmckee (420 points) [ no revision ]
the man said "try and try until you succeed", or at least my mom did :) Regardless of the failures or fabrications of Pons-Fleischmann or Rossi-Focardi, as physicists we cannot give up all hope of discovering a physically viable route to fusion, be it cold or warm, which is more elegant and efficient than the conventionally accepted plasma confinement methods.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user user346
-1 This answer is ignorant of calorimetry. The effect Pons and Fleischmann observed was energy output at 30% above the light-water control, many many sigma above their (calibrated) calorimetric error, sporadic in time, and lasting too long to be chemistry. Unless you believe that heavy water is magic, any storage and release of energy must be stored in the Pd electrode, and is restricted to 1eV per atom in a gram of Pd, a bound which was exceeded many times over. These explanations are so foolish, it is irresponsible to repeat them.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ron Maimon
@Ron Maimon: "These explanations are so foolish, it is irresponsible to repeat them." There is the obvious explanation, which is that Pons and Fleischmann were incompetent. This explanation is supported by the fact that their results are not reproducible. As a nuclear physicist who has done neutron detection, it is also painfully obvious to me that they were not competent at neutron detection.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ben Crowell
It seems that Palladium/Deuterium then can be used as an incompetent-magnet, because incompetents Paneth/Peters(1924!) + Filimonenko(1956!) + Pons/Fleischmann(1989) can't seem to avoid it. Even ignoring the reproductions since, putting myself in 1989 shoes, there is no chance that this is fake. You should be ashamed of yourself.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ron Maimon
@BenCrowell: I understand neutron detection is as much an art as a science. Fleischmann and Pons were chemists. I cannot imagine they thought they were good at neutron detection, and they surely didn't know what they were getting into. They should have sought out help, and it was a big error for them to try to go it on their own. They attempted to ship their apparatus to Harwell in 1989 where sophisticated measurements could be made, but customs prevented it from happening before everything collapsed around them. See Close for details.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Eric Walker
F&P's calorimetry was not flawless. In my whitepaper (ref'd elsewhere in this forum), I go through several problems with it, and I contend it was ignoring or not realizing these problems that led F&P to put too much confidence in their calorimetry. And I am sure they initially tried to detect gamma ray emission, thought they had found it, but it lacked the Compton edge, which showed they hadn't done the spectroscopy right, and they withdrew that sprecific claim.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Kirk Shanahan
+ 4 like - 0 dislike

Very simple! They can never repeat the results in a scientific way to demonstrate to others that it works. What's the point of science if we simply ignore the scientific method? If they did truly come up with something then they wouldn't have a need to be secretive and not show exactly what they did. If somehow they got it through accident then that is not science. Once they are able to reproduce the results and show others and others can reproduce them then it becomes useful and becomes science. (even if cold fusion is possible it is useless if we can't ever reproduce it)

The reason why cold fusion is considered bogus is mainly because many people have tried and all have failed... and those that have claimed to succeed never proved they did.

No one knows if cold fusion is possible but given all the schemes and cons that have happened in the past it's easier to be skeptical than not. If someone does discover some way then it will be VERY easy to prove and if they are true scientists they won't have any issues doing so.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user AbstractDissonance
answered Jan 25, 2011 by AbstractDissonance (40 points) [ no revision ]
I think there's other reasons that are better than this one. For example, the early lasers had difficulty with repeatability, until others learned the subtle techniques having to do with power supply wire impedance, etc. In general, any new thing is experimentally difficult and if you don't know how it works you will have difficulty repeating it because you don't know exactly what it is that you're repeating. (I.e. does the color of the paint matter? Might if there's a chemical in the paint that's critical.)

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Carl Brannen
Um, no, your totally off the point. I'm not talking about measurement repeatability but something that folks in the know call the scientific method... learn it and reread what I said.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user AbstractDissonance
The scientific method (sm) had nothing to do with the past scientific revolutions of Newton, Einstein, .. (I'm not saying that sm is irrelevant to the small incremental steps) . Intuition and hard-work against the Establishment is the norm.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Helder Velez

Confidently stated as if fact:

They can never repeat the results in a scientific way to demonstrate to others that it works.

The reason why cold fusion is considered bogus is mainly because many people have tried and all have failed... and those that have claimed to succeed never proved they did.

 "Cold fusion" is not well-defined. However, if we use it as shorthand for the Flleischmann-Pons Heat Effect, this was well-confirmed by 1991, and confirmed as a nuclear reaction by the work of Melvin Miles, first announced in 1991, and subsequently confirmed by many.

See the February 25 issue of Current Science, Special Section on Low Energy Nuclear Reactions and my paper in that section, which covers the confirmed reproducible experiment (i.e, the measurement of the heat/helium ratio from the FPHE.)

The rejection of cold fusion was a "cascade," a social science phenomenon, where someone prominent gives an opinion, and it is taken up and echoed broadly until it is viewed as a consensus, without actual investigation. That there was no confirmation is a common meme, and is blatantly false.

+ 3 like - 0 dislike

Why was cold fusion considered bogus? Because it was not easily reproduced when initially announced, because the original suggested mechanism was inconsistent with known physics at the time, and because the evidence presented at the time purporting to show it was nuclear fusion (specifically D-D fusion) was flawed.

Perhaps the better question is: Should it be considered bogus today? No, not completely. There are many instances of similar results available, yet the effect is not under control yet. The best reason for that is that the researchers are attempting to control the wrong things when they do their experiments, and that ends up with a lot of different results depending on what values the real controlling factors took during the experiment.

There are conventional explanations for those semi-reproduced results that suggest other things to control, but which the cold fusion researchers fail to employ becasue they refuse to consider non-nuclear solutions. For more details see the URL below and read it and references therein:

https://docs.google.com/open?id=0B3d7yWtb1doPc3otVGFUNDZKUDQ

(ref'd in http://www.networkworld.com/columnists/2012/102612-backspin.html?page=1)

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Kirk Shanahan
answered Nov 6, 2012 by Kirk Shanahan (30 points) [ no revision ]
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BTW, a further comment on this Maimon K-shell theory thing. Most of the time, there is no observed CF effect, special circumstances must be created, and I never have heard of any CFer exposing apparati to keV radiation. So how does one normally get CF from this K-shell eletron thing then?

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Kirk Shanahan
You are confusing photons and charged particles. Photons must be tuned, charged particles produce keV holes with no tuning, this is Bethe formula ionization. The limitations to a band is that you need to concentrate the holes suffficiently in a region to allow fusion, this might require a strong surface electric field, concentrating the deuterons to allow d-d fusion (whose rate is quadratic in the d-density). You also need to seed the reaction, so you need some trace amount of charged particle radioactivity on the Pd. This is eventually inevitable, crud accumulates on the cathode.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
There are several possible reasons for "special conditions", you might need trace alpha-emitters on the cathode, which might vary from sample to sample or from the solution type, you might have different cosmic ray or background radioactivity, which might be the trigger, or it might be due to the required surface electric fields to concentrate the deuteron-k-shell hole into sufficient density to ignite the reaction. Who knows. Because people such as yourself have willfully prevented research the topic, there is very little that can be said definitively. But I am sure now my mechanism is right.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
And why wouldn't one consider a beam of eletrons a beam of charged particles? Shooting a 2-3 keV beam of electrons at a metal produces Auger electrons (and sometimes gammas too) in the vicinity of 1-1000 eV, clearly not a resonance condition, from K and L shell holes and their filling by valence electrons; a very well defined surface analytical technique. I think your criteria and theory are off base, but I admit I am not qualified to diagnose your problem. you'll have to get someone else.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Kirk Shanahan
Yes--- a beam of electrons would work if it at 100KeV-1MeV, but preferably a commercial LINAC at 20 MeV, this should be excellent to stimulate the cold fusion. The Auger process is what I am exploiting, except I am noting that you get Auger deuterons also in a deuterated metal, not just Auger electrons, and that Auger deuterons are delocalized and fuse, and the fusion seeds more Auger deuterons through it's K-shell holes. This is the main point. I am glad you are grappling with it, but I encourage you to keep reading and keep criticising, as you will see there is no problem with my idea.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
Most recent comments show all comments
This is not a reasonable way to evaluate a phenomenon that's sporadic and ill understood. What you want is a statistical thing--- If I order 100 different batches of Pd, load them with deuterium, you will detect tritium at levels far above negligible background in 5% of samples. This is dependent on factors people don't understand, in my opinion the most important thing is appropriate radiological contamination of the Pd, which gives a seed for the reaction to start. If you alloy Pd with good alpha emitter, you might be able to make a 100% reproducible sample (although it might also blow up).

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
Also, I saw a brief comment on 115 KeV X-ray irradiation of protonated Pd somewhere by you (can't find it again), to reply to this: the band I expect to be around 20-40 KeV (I can't say exactly where, because it is mixed deuteron and inner shell modes, and it depends on the deuteron mass, but no way it's anywhere near 115 KeV). This means X-ray irradiation at 3-4 times higher frequencies are useless, you need X-ray experiments near the Pd K-shell, to find the K-peak broadening and moving into a band with a band edge somewhere near the old K-shell.

This post imported from StackExchange Physics at 2014-03-24 04:45 (UCT), posted by SE-user Ron Maimon
+ 2 like - 0 dislike

Actually to my knowledge scientists have been able reproduce some of the experiments successfully, they just don't fully understand the process as of yet. Research is being done to come up with a working LENR theory (what it's known as in the physics community) to accurately model what is happening (unexplained excess heat generation). As some have said yes it's a very complex process and it's still possible that the energy is liberated from some other means (non-nuclear) but I would hardly say the it's completely been proven on way or another. A good website for learning more is http://lenr-canr.org/

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user adechiaro
answered Feb 1, 2011 by adechiaro (20 points) [ no revision ]
Quoting your good website: No attempts to replicate this by other groups have been reported

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user gigacyan
No, cold fusion has never been reliably reproducible. Whenever anyone competent tries to reproduce it, it doesn't happen. See, e.g., Gai et al., "Upper limits on neutron and gamma-ray emission from cold fusion", Nature 340 (1989) 29–34.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ben Crowell
@BenCrowell: Gai is not competent. The competent people are the ones who reproduced it.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Ron Maimon

The reaction discovered by Pons and Fleischmann is known to not generate neutrons at anything other  than extremely low levels. The FP Heat Effect generates helium, without a gamma, but with the right energy release, it shows up as heat. This is inconsistent with what would be expected from d-d fusion, but there are other possible reactions that will convert deuterium to helium. See my paper in Current Science, February 25, 2015.

There is another problem with Gai's work. At that point, nobody had found a way to set up the FP reaction within a few weeks. Gai's work had perhaps more relevance to Jone's announcement. Jones later did his work in a deep mine to address Gai's concerns. This isn't the reaction known as cold fusion at all. 

+ 2 like - 0 dislike

This new "cold fusion" reported in what is really a blog is a commercial enterprise to all intents and purposes. Their claims are so large, that either their constructs will be successful or they will eat their hat. We do not have long to wait.

If they are successful, the theory will be found.

One note about crystals ( they are using Ni crystals) and large energies: Along the crystal axis high energy muon beams go through intact, without interacting with the coulomb barrier. Hard to find references, I know Tom Ypsilantis was working on this in the '80s. Here is a proposal for a muon collider that uses the concept. So if the announcement is not snake water, an appropriate solid state/nuclear theory will emerge.

I am editing this to include a recent video by NASA that may be saying that the Rossi claims may not be after all totally bogus. Note the Ni28 in the table of possible elements to be used for low energy nuclear fusion ( LENR).

BTW Rossi et al are now planning small heaters! lap top size for the home market!! If it is a scam it will be the scam to end all scams !.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user anna v
answered Feb 1, 2011 by anna v (2,005 points) [ no revision ]
One of the professors I had back long ago was Joseph Weber. He was convinced that crystals could catch a high cross section of neutrinos. I recall that he got the Navy to fund it. He got positive results that no one ever repeated. At the time, grad students basically tried to avoid him. But he was a great guy. Google "joe weber"+crystal+neutrino

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Carl Brannen
this NASA patent exploring 'plasmon polaritons' and 'heavy electrons' appears to be related to that NASA video.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Helder Velez
this NASA chief scientist article "Something real is happening ... NASA LaRC has begun LENR design studies guided by ..." (found via 22passi blog)

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Helder Velez
@HelderVelez thanks for the link.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user anna v
+ 1 like - 0 dislike

If there had been a fusion process there would have also been neutron production. There were some claims of neutrons, but they were not verified. There is another problem with neutrons, if there was fusion Pons and Fleischmann would have been irradiated by neutrons. They might in fact have gotten sick or died. There was something amiss with the whole thing from the start. If they were intending to get cold fusion, why did they not shield themselves? If they did not intend to get cold fusion, but later suspected they had it, why did they not then shield against neutrons? They played around with this set up for some time, and if they really thought they were getting fusion, why did they not set the apparatus behind lead bricks? Either they were stupid or they were scamming.

The idea that interionic lattice potential could force nuclei together is ridiculous. There is a prospect for a bosonization or condensate physics. Here the D or T enter into the same quantum state and might transition into H^4. This is implausible though.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Lawrence B. Crowell
answered Jan 24, 2011 by Lawrence B. Crowell (590 points) [ no revision ]
""why did they not set the apparatus behind lead bricks? Either they were stupid or they were scamming."" Lead to shield neutrons is not unstupid as well.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Georg
I don't know what the stopping power of lead is to neutrons. You appear to be implying lead will not work. However, a moderator, maybe graphite, or something to stop neutrons would be prudent if you are doing something which geneates them.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Lawrence B. Crowell
Neutrons loose energy by contact scattering with nuclei, and loose a larger fraction on each scattering if the nucleus is light. So water or plastics are often used. Adding boron, chlorine, gadolinium, or something else with a high thermal capture cross-section can help, but will generate gammas that need to be shield with a high Z layer. Basically neutrons are a pain and the best plan is to just keep your distance.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user dmckee
The classical neutron shield is paraffin wax, Today PE or PP could be used with the same effect. The protons in the hydrogen of paraffin does the scattering. Water needs some container, parrafin not.

This post imported from StackExchange Physics at 2014-03-24 04:44 (UCT), posted by SE-user Georg

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