From: terry@asl.dl.nec.com
Subject: Re: A Good Question
Originator: terry@aslss01
Organization: (Speaking only for myself)
Date: Thu, 31 Dec 1992 23:22:06 GMT

In article <921231130918.20a05c3e@FNALD.FNAL.GOV>
DROEGE@fnald.fnal.gov writes:

> Consider two D ions sitting in a tube.  The tube is the Palladium lattice.
> Let them be at adjacent sites in the tube.  Now sneak up behind each with
> some negative charges.  Q: How many charges does it take to push the two
> together? Q: How much work is done in the process? (ev)

Not much.  The question is whether a plausible energy-focusing mechanism can
be postulated.

> Seems to me it does not take either very many ev or charges.  I don't think
> we need anything like 20 Kev, or a high voltage anywhere.  We just need a
> very high, very local electric field.

No.  If you calculate the effective voltage of the charges you are postulating,
you will indeed find them to be very high.  (The voltage gradient will also be
very steep for such a postulated arrangement.)

If you can persuade a great many electrons or ions or atoms or whatever to
symmetrically contribute their energy to a very small number of ions or atoms,
you will get some interesting hot spots.  The formation of such hot spots
could certainly be postulated to make use of field emission or some similar
effect, but something _more_ than just local gradients will definitely be
needed.  The main problem is that such steep local gradients normally have
access only to a very limited (local) quantitiy of potential energy.  You will
need potential energy contributions from a very wide range of locations in
your crystal lattice, and that implies something more generalized than the
local gradients alone can provide.

> Now if all those electrons in the lattice can just be persuaded to bunch up
> periodically, the internal net field could be very high while the external
> field is zero.

The "bunching up" is in fact the postulated energy focusing mechanism.  The
problem is to quantify it specifically and propose a way that it might be
able to exist in a transition metal lattice.  Look for mechanisms that _end_
with strong field gradients, but begin with something more gradual.  Otherwise
your attempt to focus energy will break up prematurely and nothing of any
great interest will occur.

I have no idea what such an electron-based energy focusing mechanism would be,
but it would necessarily show a high degree of symmetry when represented in
the appropriate space.  It would also have to "zero in" very specifically on
a single very tiny region of the lattice for the final focusing of energy.
(Note again the difference from "fracto" approaches, in which high gradients
occur all over the matrix and no single focus can be identified.)

> Seems to me that all those electrons in the lattice would want to lock up
> in some way.

Not normally.  You've got the metallic equivalent of an electron gas, and
unless disciplined in some curious fashion it will behave like most gases --
chaotically.

> Happy New Year to All - Lets make this a breakthrough year!

It would make a great New Year, wouldn't it?  Thanks for all the great
contributions, Tom, and for the interesting speculations that make one
stop and think.

				Cheers,
				Terry

Newsgroups: sci.physics.fusion