On 01/21/2011 03:55 PM, Roarty, Francis X wrote: > > Hi Stephan > > You state "If a tiny fraction of the nickel is transmuted each > second, and if nearly all the transmutation events produce unstable > copper which eventually decays back to (higher weight) nickel, and if > it takes multiple steps to get to stable copper, then by the time > we've got a lot of stable copper running around, nearly all the nickel > must have been transmuted at least once, and the whole lot should be > radioactive. " > > > > But if you take a relativistic approach like that suggested for lead > acid batteries you not only have the potential for fusion but > potentially rapid aging of the reactants as well... >
Aside from the obvious question of why this particular bunch of nickel powder should show a shorter half-life than all the other bunches of nickel powder that have been tested in other laboratories, the problem with what you said is that this is just a simple "urn problem, with replacement" from probability theory. Even if the half-lives were scaled up or down by an order of magnitude it wouldn't make much difference to the conclusion. By the time 30% of the nickel atoms have been "chosen" by hydrogen atoms /five times/ (which is what it takes to get from Ni^58 up to Cu^63), nearly all the rest will have been "chosen" /at least once/. And a lot of those are likely to have been chosen /exactly/ once, and the ones which have been selected just once are the ones with the 75 kY half life. Working out the details to get an exact answer would be messy, in part because a bunch of the nickel is actually Ni^60, but the point is that if any significant fraction of the resulting material were Ni^59 there should be measurable radioactivity. And there's not.
