# Tag Info

## Hot answers tagged cold-fusion

38

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 ...

10

Okay, so I did some poking around and the 66th-75th editions of the CRC Handbook of Chemistry and Physics all have the incorrect atomic mass of Cu-63 [62.939598], and from 76th edition on they seem to have figured it out. Those isotope mass tables are put together from a number of sources, so it's hard (time consuming) to tell exactly where the error came ...

9

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 ...

8

There are a few reasons. 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 ...

8

Since both references give the same percentages and the same overall atomic weight, an easy calculation shows that this only works out for the number in the first link, therefore the second decimal should be 2. (And I think it would be nice to contact the webmasters of the second link.)

8

For some recent information on the running battle between cold fusion researchers and myself over my proposed conventional (non-nuclear) explanation of the Fleishmann-Pons(-Hawkins) effect, you might want to look here: https://docs.google.com/open?id=0B3d7yWtb1doPc3otVGFUNDZKUDQ (referenced in this: http://www.networkworld.com/columnists/2012/102612-...

7

The binding energy curve for nucleons in nuclei shows which atoms can take part in fusion, releasing energy in the process. Fusion happens as one goes from left to right, until reaching Fe, iron. From there to the right it is fission that will release extra energy This is an example of a fusion reaction, the one that is actually being materialized in ITER,...

7

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 ...

4

I suppose I did not make myself clear, and spent too much time talking about stellar evolution. The main reason why this cannot work is that, when you are working with elements that have atomic numbers higher than Iron (26), you cannot get energy by converting an element into another that has an even higher atomic number. In this case we're converting Ni (...

4

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 ...

4

Muon catalyzed fusion needs the muons to be low enough energy to replace an electron and stay in a stable orbit. Since the reason the catalysis happens is because the atom is much smaller and two protons can get close together enhancing the probability of overlap and fusion, one needs a large number of low energy muons so that the probability of two muonic ...

4

A seemingly problematic aspect of the proposed mechanism is that it allegedly requires two hot deuterons. (By contrast, U-235 fission requires just one neutron.) Why is that so problematic? If $n$ is the number of 20keV particles (i.e. hot deuterons, or K-shell holes, or some superposition of them), then we expect something like: $$dn/dt = An^2 - Bn$$ ...

4

Please note, that this test was conducted by exactly the same group that did the previous test, lead by Guiseppe Levi, who is closely connected to Andrea Rossi. Also, you can read from the report, that Rossi himself was present in the test pulling the strings. Hardly independent testing, is it? The above facts alone are enough to make the report somewhat ...

3

Cold fusion does not exist, as discussed in the answers to this question. The fundamental reason for this is the mismatch in energy scales between the Coulomb barrier (MeV) and the energy scales of chemistry. Changing one of the chemical reactants from Pd to Ni has no effect on this fundamental issue. The linked true-believer article, dated August 2012, ...

3

There is a claim often made about cold fusion, that it is excluded theoretically. The main theoretical argument is that electronic energies are too low to overcome the Coulomb barrier, since d-d fusion only takes place at KeV energies, while chemistry is at eV energies. This is belied by inner shells, which in Palladium store 3 or 20 KeV of energy per ...

3

I'm an experimental electrochemist. The problem with experiments such as those mentioned above is that they lack the necessary details to reproduce it, so that we can verify it or improve upon it. In the first video, a paper linked is here: http://www.lenr-canr.org/acrobat/SzpakSpolarizedd.pdf They vaguely mention a "negatively polarized Pd/D$_2$O system". ...

3

Without knowing anything about the experiment nor the camera, I would suggest that what is shown in the video is a combination of shot noise and aliasing due to a poor choice of gradient mapping. Note that the gradient bar at the bottom of the frame jumps from a fairly deep red (actually darker than precedent tones) to pure white in one increment - this may ...

3

Moun catalyzed fusion requires very specific kinematics, but cosmic muons come in all energies from stopped to tens of GeV at any particular spot. Care to work out the cross-section for having the right kinematics? If you're having trouble I know a graduate student who is familiar with several of the common cosmic muon Monte Carlo generators.

3

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 ...

3

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 ...

3

The 2003 Atomic Mass Evaluation: Cu(63) - 62.929597474 The 1995 Update to Atomic Mass Evaluation: Cu(63) - 62.929601079 The 1993 Update to Atomic Mass Evaluation: Cu(63) - 62.929600748

3

You seem to have invented a version of the Farnsworth Fusor, and/or its successor Polywell. Or, if you want a neutron generator you can hit something like Palladium that has absorbed a load of Deuterium with your beam, or a metal Deuteride

3

The difficulty with this sort of device is that the effective cross section of the target nuclei are so tiny. Even with a very dense target, most of your shots will miss. But you still have to consume energy to send them along. The most important thing for efficiency then is nuclei density in the target. Making the target full of negative ions isn't ...

2

I've started a discussion on this at the Wikipedia article. If I had to guess at the origin of this discrepancy it is a typo in one of the old CRC's where someone typed '3' instead of the correct digit of '2'. If that's the case there may have been merely an internal memo correcting the typo -- if that.

2

Fake. Real thermonuclear reaction would kill everything around due to heavy neutron radiation. Even 1 meter of lead would not help.

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