RE: Popular Mechanics August Issue - H-bombs and Cold Fusion

["Dukelow, James S Jr" <jim.dukelow@PNL.GOV>]

Bob Cherry wrote:

-----Original Message-----

From: owner-radsafe@list.vanderbilt.edu on behalf of bobcherry@cox.net

Sent: Mon 8/2/2004 10:30 AM

To: radsafe@list.vanderbilt.edu

Subject: Re: Popular Mechanics August Issue - H-bombs and Cold Fusion

 

My objection to the idea of "cold" fusion has always been based on the law of conservation of energy. I haven't seen the below argument anywhere, but that doesn't mean I am the first or only one to propose it:



1.	In order to fuse light nuclei, you must get them close together.



2.	The nuclei both have a positive charge, so you somehow must overcome the Coulomb force to get them close together.



3.	The Coulomb force is a conservative force, meaning that the amount of energy necessary to get the nuclei close enough to fuse is independent of the path you follow to get them there.



4.	"Cold" fusion offers no way to input this required energy.



In other words, "cold" fusion appears to me to be a perpetual motion machine of the first kind (it violates the law of conservation of energy), which is impossible.



The two main contenders for commercial fusion power, lasers and inertial (magnetic) confinement, both input large amounts of energy to achieve fusion. If and when one or both of them is commercially successful (as an optimist, I prefer "when"), the energy output from fusion will exceed the energy input. So far, this only occurs in stars and the hydrogen bomb. I predict that it will never occur on a tabletop at room temperature.



Bob Cherry



==================



Regarding the conservation of energy argument, the question: "Is the amount of energy required to bring two atoms (D and T or T and T) close enough together to fuse greater or less than the energy obtained from the fusion?"  If more, then we can give up the effort to achieve commercial feasibility by any approach.



If less, then we should recognized that hot fusion and cold fusion (either the P-F approach or the more recent sonoluminescence approach) have very different energy requirements.  Hot fusion is typically trying to establish sustained fusion with many moles of D and/or T.  It has faced and continues to face daunting challenges to sustained stability of the D/T plasma.  On the other hand, P-F claimed to show fusion in minimole quantities and sonoluminescence experiments are probably working with micromole quantities.  It is unclear (to me) what the physical mechanisms for P-F fusion (?) might be, but the bubble compression in sonoluminescence is physically pretty straight forward, although it has been difficult to establish the peak temperatures and pressures in the collapsing bubble.



Best regards.



Jim Dukelow

Pacific Northwest National Laboratory

Richland, WA 99352

jim.dukelow@pnl.gov



These comments are mine and have not been reviewed and/or approved by management or by the U.S. Department of Energy.



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