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Cold Fusion: What is wrong with this picture?
From: allred@ut-emx.UUCP (Kevin L. Allred)
Subject: cold fusion -- what is wrong with this picture?
Date: 24 Apr 89 20:45:28 GMT
Organization: UT-Austin, Dept. of Chem. Engr
Xref: santra alt.fusion:587 sci.physics:6297
Posted: Mon Apr 24 15:45:28 1989
I have been reading the postings about cold fusion since they began
appearing almost a month ago, and I have forwarded a number of
interesting postings to my brother who is a professor of physics at
Brigham Young University. He formulated his thoughts on the subject
and asked me to post this for him. As he does not have USENET at his
sight, replies should be sent to him at his internet address:
Comments on the abstract of the preprint on "Catalysis of Deuterium
Fusion in Metal Hydrides by Cosmic Ray Muons" by Guinan et. al. of
LLNL. Their model is at odds with all that is known about muon
chemistry. The muon stops on atoms according to the Fermi-Teller Law.
In a mixture or compound the probability that a muon stops on an atom
is according to its atomic number, Z. Thus in SiC, for example, the
Si would get the muon 14/(14+6) fraction of the time and C 6/(14+6)
fraction of the time. There are deviations to the Fermi-Teller Law
but they are not large. There is no evidence anywhere that a large
heavy atom can become "invisible" as the abstract claims. It gets
worse for their argument. Once the electron in captured by an atom it
starts falling down the energy levels towards the 1s. If it is
captured on an atom with z equal or greater than 2, it will normally
be stuck. If is captured on one of the three isotopes of hydrogen, it
will form a very small neutral atom. The muon is massive so that the
Bohr radius is very small. This will drift through the surrounding
matter basically free. Because it is neutral, it behaves much like a
neutron, free to penetrate deep inside the electron clouds of the
surrounding atoms. Its path is random and may take it near other
hydrogen nuclei or the nuclei of other atoms. The first is the origin
of muon catalyzed fusion as normally understood. The second event
leads to the transfer of the muon to the heavy atom, where it is lost
to fusion catalysis. Work has been done on muon chemistry in a
variety of compounds as well as hydrides. See, for example, Knight
et. al. Phys. Rev Lett. 38(1977) 953. and R. A. Naumann Zeitschrift
Fuer Physik A291 (1979) 33. The heavy atom gets the muon sooner
rather than later. A more telling argument against the muon model
will be statistics. The cosmic ray muon model will require 700
neutrons in one microsecond. Only if the muons seen in the D-D
experiments come out in microsecond clusters will that be viable. If
they don't the model has little validity.
Concerning Hagelstein's work: Abstracts, of course, don't tell the
whole story but his efforts seem to be aimed at shoring up the
hypothesis that D+D goes to 4He plus more than 22 Mev Energy. He has
tried to invent schemes to get the energy out into the lattice without
the presence of lethal and very detectable gamma rays. The idea of
doing that is hardly original. Where people are showing their
creativity and style is inventing schemes.
All I have seen fall flat when you consider basic laws of physics like
conservation of momentum, entropy and the like. I have trouble with
the arguments because the scales of the phenomena - nuclei vs atoms -
are so different. 20 MeV of excess energy in the 4He compound nucleus
is about 4 million times the energies seen in normal condensed matter
(solids, liquids and gases). The nucleus is unbound by a few MeV.
Entropy and experience show that the excess energy will be dissipated
by the quickest way possible. The protons and neutrons in the nucleus
are moving relative to one another, colliding and redistributing the
energy they suddenly share at a frightful rate. It doesn't take long
until one nucleon, a proton or a neutron, ends up with most of the
energy and it moves away from the rest.
The strong force attraction between it and the nucleons it leaves
behind falls to zero and the Coulomb repulsion, in the case of a
proton, takes over. How long does this take? Blinding speed but it
can be quantified. The speed of a 2.5 MeV nucleon (neutron or proton)
is about 0.07 times the velocity of light that is about 20 million
meters a second. Nuclei are small, about one fermi or 10 to the -13
meters. It takes a nucleon about 5 times 10 to the -21 seconds for it
to move about one fermi and that is about how long the original
compound nucleus lasts.
In order for the compound nucleus not to decay with the emission of a
neutron or proton the energy has to be siphoned off in 10 to the -21
seconds. That is hard to do. Even the formation and emission of a
gamma ray, a high energy photon, is unfavorable relative to the
emission of a nucleon. In the time frame of this decay the atom's own
electrons, neighboring atoms and their electrons are frozen in space.
The characteristics time for atoms to vibrate in their position is
about 10 to the -13 second. This is still blindingly fast in human
terms but 100 million times slower than the time the nucleus takes to
decay. This is about the same ratio as 3 years is to one second.
It doesn't do much good to transfer the energy to the electrons in the
solid either. As others have observed, if you transfer all 20 Mev to
one electron it will be relativistic and give off the characteristic
"blue glow" seen above swimming pool reactors. If you imagine that
the energy is given to many electrons so that they are not
relativistic you are faced with the problem of getting thousands if
not millions electrons to each receive a small portion of the energy
which must be dissipated. Even if there were a mechanism to do this
the time frame is wrong. The energy can travel to the electrons no
faster than the speed of light. The diameter of atoms is about 2.5
times ten to the -10 meters. It takes light 10 to the -17 seconds to
reach 10,000 atoms around a point and ten times that long to reach
millions of atoms. This time is thus 10,000 to 100,000 longer than
the time in which the energy will be released from the compound
nucleus by the release of a nucleon.
To put the energy scales in to more understandable terms let us move
from the arena of eV to that of gravitational potential energy and the
earth. Let each foot that a standard object, lets say for example a
glass of water, is raised above the surface be one electron volt (1
eV). This means that people operate in the range of several eV. This
is like a solid. Nuclear potentials are much higher. The greater
than 20 MeV compound nucleus corresponds to a glass of water at 20
million feet -- about 4000 miles up!! Imagine that the glass of water
is balanced on the top of a pole 4000 miles high and your job is to
lower it safely to the ground without spill a drop ever, and you will
get an idea how improbable it would be to imagine the energy will
consistently be removed from the compound nucleus as atomic
excitations. Remember that this must happen 99.999999 % of the time
or else far more neutrons and tritium will be produced than anyone has
seen in the Pons-Fleishmann effect.
I'm quiet sure that some have postulated or will come up will special
stabilization mechanisms that will keep the nucleus together while the
energy is safely drawn off. Such attempts are usually improbable at
best and, to me, sound too much like Deux ex Machina solutions. If
there really is fusion then some unlike explanation must be true, but
in spite of four weeks of work, there remains no good evidence that
the Pons-Fleishmann thermal effect is fusion except for wishful
thinking and the fervent testimonials of true believers. Until the
numbers come out right it isn't proven to be fusion and it should not
have been announced that it is. The physical sciences are first and
last numerical and insufficient attention has been paid to numbers by
apologists for the P-F thermal effect.
In fact with respect to the Pons-Fleishmann thermal effect, the whole
area, increasingly sounds like the "true believer" syndrome. Some
people are latching on to the smallest signs as confirmation and
castigating the skepticism of others as on one hand, the fussiness of
physicists who would rather preserve their equations than walk through
the door way of "cold fusion" into the new age, or on the other hand,
the self-interest of the fusion establishment who doesn't want to see
their funding dry up. Inevitably, a nuclear confirmation of the
Pons-Fleischmann thermal effect is billions to trillions of times too
small and many times disappears upon close scrutiny. There may be
some fusion occurring in the Pd wires, but if so, it releases less
than one billionth the energy claimed to be seen. It is difficult to
see why first, so many people rush to claim they have seen the effect
before they can systematically check and compare with other results,
or why second, others propose nuclear explanations, apparently without
doing simple calculations.
As an example of the first consider the lack, until recently, of the
control experiment of using normal water. For an example of the
second (without apparently doing simple calculations), consider the
explanation by a Texas A&M chemist that the reason neutrons weren't
seen in the U of U experiment is that the branching ratio changes so
that protons rather than neutrons emerged from the compound nucleus.
Even if you ignore the argument that nuclear processes can't, and
don't, depend strongly on chemistry, the alternative quickly leads to
a contradiction. The energy level for the P-F thermal effect requires
about 10 to the 13th fusions per second. In one day this leads to 10
to the 18 atoms of tritium. Even if it took a while for most to make
their way out of the Pd, a finite fraction would emerge within a day.
How much radiation do you get from 10 to the 18 atoms of tritium?
Well, the half life of the tritium as most now know by heart is 12
years; there are 3 times 10 to the 7 seconds per year, so the decay
rate for tritium is about 10-8 per second. The supposed amount of
tritium would then give you 10 to the 10th decays per second. The
definition of a curie is that quantity of a radioactive material that
gives you 3.7 time 10 to the 10 disintegrations per second. Thus the
experiment with the supposed branching ratios would have produced
curie levels of radiation every three or four days and, no matter what
mechanism for diffusion you postulate, released millicurie levels of
tritium into the room. Since tritium exchanges rather freely with
water in human beings, such levels are hazardous and would be noticed.
Journalists aren't familiar with such matters and may be forgiven for
not catching the error, but why didn't the people who postulated the
mechanism catch themselves right away before they went public. The
argument I just went through should be generally well known by now.
It is simple enough that no one can claim brilliance for coming up
with it. What is remarkable, bordering on scandalous, is that those
that proposed the process as a way of escaping the neutron dilemma
apparently didn't do the calculation. At least the press gave no
indication that they had reservations of this type. We teach such
calculation in the beginning university physics series and in
undergraduate physical chemistry. The numbers are not hard to find.
Maybe there is a shortage of envelopes for "back-of-the-envelop
calculations". The question of the hour may not be "Where are the
neutrons?" or even "If it is fusion?" , the question may be "Why
can't Professor Johnny think?" Maybe its too much pressure, the worry
that if you don't say it someone else will.
The case of 4He which has presumed to have been seen in the U of U
experiment may fall into the same categories. Determination, in part,
was reported to have been by mass spectroscopy. Unless extraordinary
care is taken and/or a mass spectrometer capable of resolving the mass
defect part per thousand of one amu is available (and preferably
both), the helium will be obscured by D2 molecules which we know they
have in abundance. The solution is to catalytically burn the gas
coming off. Helium will they be apparent.
Whatever the case may be, many are growing weary of seeing the
headlines, mostly in Utah, scream "Fusion Confirmed Again", by which
is meant the P-F thermal effect and maybe a few neutrons and/or
tritium in the parts per trillion or parts per billion range has been
seen again. Again, until the numbers come out right it isn't
confirmed fusion and it should not be announced that way. To do
otherwise, is like finding a few dollars in change in the desk of some
government official and saying "Great, now we can pay off the National
debt." In fact, since those who claim to have seen the effect are
only a factor of ten or so off on attributing the effect to chemical
sources and off by billions on attributing it to nuclear sources any
unbiased observer will give you odds that the P-F thermal effect is
chemical not nuclear. The physical sciences are first and last
numerical and more attention has to be paid to numbers by anyone who
reports on the P-F thermal effect. The P-F thermal effect as fusion
energy is dead unless the numbers come out, and those who will explain
it must go through the numbers carefully.
But perhaps, we are to the point that, in the near term, the most
profitable work on "cold fusion" and the P-F effect will be done by
social scientists. Like anthropologists studying the interaction of
the scientific community, political scientists studying the role of
technology in decision making and psychologists studying modern mass
The whole area is ripe for humorists, in any case.
A local wag, Ray Perkins, has made this observation.
"In order to explain the experimental data of the recent past, a new
physical principle has been formulated. It is an exclusion principle
'You can measure heat, or you can count neutrons, but you
can't measure both at the same time or in the same experiment. '
(This is a slightly altered version of the one recently formulated by
P. Matheson. Some call this the Ponzi effect since it leads to a
pyramid of press releases)."
Dr. David D. Allred
Department of Physics
Brigham Young University
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