Hi Robin, many thanks for your corrections. Indeed momentum p is the denominator of the De Broglie wavelength h/p, my mistake. So in fact the more immobile the target deuteron, the less close the incident deuteron needs to get in order to fuse...
1/ Wouldn't it therefore dramatically improve things if we threw (by electrolysis, gas discharge or whatever) the incident deuterons onto a deep-cooled deuteron desorbing cathode? (liquid deuterium in a back side chamber could provide the deuterium, the low temp and the pushing pressure maybe) 2/ Another thought triggered by your correction, forced cooling or not, isn't a deuteron about to desorb (for Jones's entertainment: stuck half way through the surface Pd "sphincter") particularly immobile due to its squeezed condition, and therefore an easier fusion target? 3/ I have found this 2002 paper "Study on Physical Foundation of Cold Fusion" : http://www.swip.ac.cn/cfs/english/Information/nb2002/024.2.pdf The English is very poor but the physics seem quite understandable, even to this QM ignoramus. I find the "volcano section view" shaped potential curve quite helpful: positive hill shape is Coulomb repulsion potential (hill is lowered and narrowed by any screening negative charge density I guess), narrow central pit going down to very negative values is nuclear force attraction potential. Summary of my understanding of this paper: in order to fuse i.e. fall into the pit an incident deuteron doesn't have to classically go all the way up the hill, instead it can tunnel through it if it gets closer than the target's De Broglie wavelength. It seems the incident deuteron can be treated as a classical point charge loosing KE and gaining PE to find how high on the hill --and therefore how close to the target deuteron-- it gets. Your comments on the paper or my summary welcome. 4/ Do you have a ref for your factor 10 to 20 (0.035 to 0.07 Å instead of D2's 0.7 Å separation) required for practical D-D fusion power production? Cheers, Michel ----- Original Message ----- From: "Robin van Spaandonk" <[EMAIL PROTECTED]> To: <vortex-l@eskimo.com> Sent: Saturday, April 26, 2008 1:20 AM Subject: Re: [Vo]:Re: HUP-spread-out electron "feels" (and thus Coulomb-screens?) like a point charge... In reply to Michel Jullian's message of Thu, 24 Apr 2008 19:09:25 +0200: Hi, [snip] >No it wouldn't be, but even with my limited QM skills, I know that fortunately >you don't have to get that close for nuclear fusion. Nucleus is fm scale >(10^-15 m), but its De Broglie wavelength (roughly the distance at which >tunneling can start occurring) at even room temperature thermal energy is >quite sizeable, 0.78 Å IIRC, about 100000 times larger, and even more at >higher energies of course. Actually De Broglie wavelengths *decrease* with energy. (momentum is in the denominator). > >So an impinging deuteron getting only as close as say 0.5 Å from the desorbing >deuteron would have good chances to tunnel to it and fuse I think, correct me >someone if I am wrong. The chances are a lot less than "good". What you need is a means of keeping them in close proximity for extended periods. e.g. the fusion half-life of D2 (with a separation distance of about 0.7 Angstrom is > 1E80 years. However this decreases insanely with separation distance. A decrease in distance by about a factor of 10-20 should be enough to reduce it to the point where fusion would be a practical energy source. [snip] Regards, Robin van Spaandonk The shrub is a plant.
