From: jeff davis (jrd1415@yahoo.com)
Date: Tue Mar 05 2002 - 01:25:38 MST
Extropes,
If you haven't already done so, do a google search on
sonoluminescence. Then check it out. The first hit
is as good a place as any to start:
http://www-phys.llnl.gov/N_Div/sonolum/
Here's a snippet:
Sonoluminescence has created a stir in the physics
community. The mystery of how a low-energy-density
sound wave can concentrate enough energy in a small
enough volume to cause the emission of light is still
unsolved. It requires a concentration of energy by
about a factor of one trillion. To make matters more
complicated, the wavelength of the emitted light is
very short - the spectrum extends well into the
ultraviolet. Shorter wavelength light has higher
energy, and the observed spectrum of emitted light
seems to indicate a temperature in the bubble of at
least 10,000 degrees Celsius, and possibly a
temperature in excess of one million degrees Celsius.
--------------------------------
This is absolutely fascinating. I remembered reading
the article on sonoluminescence that appeared in Sci
Am in 1995. (But I haven't been able to access it
again tonight on the web because Sci Am wants me to
pony up some cash for the priviledge, and, well,
that's not gonna happen.) The high temperatures
suggested (required, proven(?)) by the production of
light--in the uv no less-- would seem at least logical
from conditions of spherical symmetry. The geometric
and mathematical elegance of this phenomenon is
breathtaking. A finite amount of energy is compressed
into a volume which approaches a point--ie zero
volume--which would result in an infinite energy
density and an infinitely high temperature. Clearly,
before such a "singular" point is reached, real world
factors will intervene: absorbtion and reemission by
the compressed medium, energy spread-out arising from
a finite length spectrally-complex wave front, and
imperfect focusing due to asphericity in the bubble,
(others?).
Whatever. Who can claim a sophisticated understanding
of this phenomenon? Not me, certainly.
What really makes this delicious for me is the cold
fusion connection. When Ponds and Flieschman had
their controversial moment, there was no plausible
mechanism to support fusion in a flask. Now that there
is, we can look back on the cold fusion controversy
and see it in a whole new light (nice little pun,
that).
If one assumes that they actually did stumble on
something, then it's clear that they did so by
accident. They wanted to capitalize on it--patent
it-- but couldn't, because frankly, they themselves
didn't have a handle on it. And no one that followed
up on F & P's work could get a handle on it either,
despite tantalizing hints, fleeting and dubious, that
there was something there. So, of course, with no
plausible proof of a means to surmount the
electrostatic repulsion energy barrier, and ever
fearful of reputation damage, the scientific community
retreated to the safety of life as it had been before
the "irrational exhuberance", and cold fusion was
relegated to the annals of crackpot science.
It was clear to the respectable scientific community
that cold fusion was not possible. The laws of
physics made that quite clear.
I remember, back then, looking for a "location" within
the palladium where the fusion might take place.
Seeking out the structure of the unit cell, looking at
the shape of the spaces between palladium atoms where
the absorbed deuterium might drift, its own electron
indestinguishable from the sea of free palladium
conduction band electrons. Wondering how this
minds-eye scene, with its particular geometry and
electronic environment, could promote the postulated
event.
My best guess was that the electrolysis power
supplies, which were DC, but which provided that DC by
conversion from 60 hz AC line voltage, retained a
slight residual 60 hz and higher harmonics, AC signal,
piggybacked on the DC. And that this caused the
oscillation which accelerated the deuterium nuclei
within the palladium matrix. That was my shot at an
answer.
Now we get to revist the Ponds and Fleischman
experimental apparatus, with plausible mechanism in
hand, and ask ourselves, "Is some previously unnoticed
acoustic activity, some variant of the
sonoluminescence mechanism, going on here?"
Only time will tell what's really going on, and I'm
looking forward to the adventure of discovery with
pleasant anticipation. But what it really boils down
to is that, as has so often been the case in the past,
what was once obviously impossible, is now, well,
maybe not.
Or as my boy Ray says:
"Everything's hard till you know how to do it."
Best, Jeff Davis
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