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Comment by ajarmst | Hacker News Reader

James Mahaffey, Atomic Adventures (Pegasus:2018 Reprint): 'A couple of things about the announced phenomenon bothered me greatly. Both Pons and Fleischmann had claimed over and over that their apparatus was producing “tremendous” heat and “measurable” neutrons. On the news, they were shown hovering over their operating fusion reactor, closely examining the apparatus as the oxygen and deuterium bubbled. That didn’t make any sense. It should have been the other way around—tremendous neutrons making measureable heat. If they were, in fact, making tremendous heat, then they would have been killed by the heavy neutron flux and secondary radiations broadcasting out of the unshielded deuterium-deuterium fusion reaction. Maybe the problem was their definition of “tremendous?” The cooling water in which the fusion cell was suspended wasn’t boiling or even misting up their glasses.'

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    Maybe the problem was their definition of “tremendous?” The cooling 
    water in which the fusion cell was suspended wasn’t boiling or even 
    misting up their glasses.'

Well, yes? According to Wikipedia, what F&P reported was an unexplained 20 °C rise in temperature.

That is a tremendous increase in temperature... when the expected amount is zero. But not exactly a "kill everybody in the room" amount of heat, right?

    For most of the time, the power input to the cell was equal to the
    calculated power leaving the cell within measurement accuracy, and the
    cell temperature was stable at around 30 °C. But then, at some point
    (in some of the experiments), the temperature rose suddenly to about
    50 °C without changes in the input power.

It seems to me that there are large numbers of problems with their claims! But the temperature thing doesn't seem to be one of them?

Please don't misunderstand. I'm not arguing that they achieved cold fusion. Anybody with a shred of skepticism should assume they didn't, until proven otherwise via reproducible experiments.

People are not getting killed by the heat, but by the radiation needed to do that. My math on radiation is a bit shaky, but to heat water by 20 degrees, it needs to absorb 80000 Grey, isn't it. Now we can also assume that most radiation was not confined to the water. The dose to get a person sick is 2 Grey and 10 Grey (full body) is almost always fatal. Making a few leaps in logic here and it depends on how much water was heated, assuming it was in the litre range, then beeing close to such a device seems likely to be unhealthy.

I get what you’re saying, but I was reporting Mahafee said about the response of scientists to the first press conference. They were not claiming that their new type of deuterium fusion didn’t have the same relationship between generated heat and neutron flux. They were claiming it was ‘fusion’ generating ‘tremendous heat’ which was completely inconsistent with them standing next to it unharmed. The (still dubious) claim that this is a different type of ‘fusion’ that has different features came much later. I’ll very happily withdraw criticism if someone (1) publishes a properly reviewed study that is replicable and (2) make a convincing case for a theory that explains the phenomenon that is consistent with other observations of fusion. After several decades, we’re still not seeing any real progress on either of those, so I remain pretty confident of my skepticism.

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