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Aneutronic fusion exists. Neutrons were expected by some because normal fusion produces them ... but if it is cold fusion, there's no reason to believe that wo
by at_a_remove 6y ago
Aneutronic fusion exists. Neutrons were expected by some because normal fusion produces them ... but if it is cold fusion, there's no reason to believe that would happen. Indeed, you should throw out as many expectations as you possibly can if you're dealing with a new process.
The first and best measurement to contemplate is the presence of helium. Of course, you have to worry about how much is in the atmosphere, and then how much might somehow be trapped in the bulk material of the apparatus itself. Still, a sudden surge of helium well beyond that of what might be found in the atmosphere would be telling.
We all remember calorimetry from high school and just how difficult it was to do proper measurements. And who knows what odd chemical reactions might release or subtract heat when you sit around cooking metal for a long period of time? No, calorimetry is error-prone and has too many miserable confounding factors.
Still, the only way to know you have fusion is to say "I have less of this lighter element and more of this heavier element." Everything is is just hoping that the assumptions from stellar fusion carry over. I'll believe it when I see it, but I also won't believe it until the accompanying papers talk about helium, and lots of it (or lithium ...).
- jboy55 6y agoYou don't have to use assumptions just from stellar fusion. You can use the evidence from all the nuclear testing, from fusors or from cosmic ray analysis. The science behind fusion and what byproducts would come from it are also explained by the standard model.
- simonh 6y agoIf it's a new process and doesn't exhibit any of the known characteristics of fusion, how do you know it's got anything to do with fusion at all? The tragedy of this story is that the word fusion ever got attached to this phenomenon. To this day we have no evidence whatsoever that any form of fusion is associated with these experiments. What we do know is that F&P thought they had found evidence known to indicate fusion, but they were wrong and had misinterpreted it.
- at_a_remove 6y agoI said it in what I wrote, but I will say it again: there is precisely one characteristic to care about ... helium. If you have some hydrogen atoms, and then you do something to them, and suddenly you have some helium atoms, that's fusion.
- pfdietz 6y agoOr contamination, or measurement error, or fraud...
- at_a_remove 6y agoI think I adequately covered contamination when I mentioned the atmosphere and the possibility of the helium being captured in the bulk of the apparatus already. As to the last two, those are an objection you could point at, well, every experiment in the history of science and are therefore not really worthy of mention.
- pfdietz 6y agoYou wrote: "If you have some hydrogen atoms, and then you do something to them, and suddenly you have some helium atoms, that's fusion." And that's just wrong. There's a famous case from early on in the history of nuclear physics, where someone passed current through hydrogen gas and then found helium, and thought it was fusion. But what it was was helium diffusing out of the glass of the apparatus. This should be the default assumption, because supposed cold fusion making 4He is a triple miracle: first that DD fusion occurs at all, then that it makes 4He, and then that it doesn't go through the normal channels (actually a quadruple miracle, since also that the 4He fusion doesn't dump its energy in very energetic gamma photons.)
- at_a_remove 6y agoRead the original paragraph I wrote. C'mon.
- andrewflnr 6y agoI always thought the idea was the hydrogens are fusing with the metal lattice, or impurities in the metal (more likely to be exothermic, I guess), in which case you won't get helium after all.
- at_a_remove 6y agoNo, the overall concept in the metal lattice was that the lattice itself brought the hydrogens closer in some way, or lowered the potential barrier between them. Also, it's palladium. Getting hydrogen to fuse with palladium is a net loss of energy, which would be amusing in a sad way. "Guys, we got fusion to work, but it actually takes energy!"
- jboy55 6y agoJust a note, if you are going to throw away the rule book (standard model) because its 'cold' fusion, you can't then say that hydrogen palladium fusion is a net loss of energy. If being cold changes everything so much, who knows under cold conditions if it's a net gain?
- at_a_remove 6y agoOh, I'm not suggesting throwing away the Standard Model (although it has its known quirks and I am assuming you are referring to the Standard Model), but you don't need to do that to say that hydrogen palladium fusion is a net loss of energy. That just takes your basic addition and subtraction and keeping hold of a little thing called conservation of mass-energy. That ... I am not throwing out the window. I am only saying that we retire to the most basic definition of fusion: a bunch of atoms of lighter elements become, through some process, fewer atoms that have some heavier elements in the mix. I am in no way suggesting that binding energy doesn't exist, etc.