lew@ihuxr.UUCP (08/28/83)
Last June 22 Paul Dubuc posted an excerpt from "Origins Research" that responded to Niles Eldredge's book "The Monkey Business: A Scientist Looks at Creationism". This excerpt contained several references to Science magazine. I have looked up four of them and would like to summarize them for interested net.readers. The first was one of three about pressure changes affecting radioactive decay rates. (The other two were to other journals) : Hensley W.K., Passet W.A., Huizenga J.R. "Pressure Dependence of the Radioactive Decay Constant of Berylium-7" Science, Vol. 18, Sept. 21, 1973 (pp. 1164-1165) These authors report a pressure dependence of the decay constant of (2.2 +/- .1) * 10^-5 /kbar. Well, question is, what is the relevance of this to dating techniques? The magnitude of the dependence is extremely small for the range of pressures found in the earth's crust. In "The Earth" by Sir Harold Jeffreys, we find the statement (p. 406): "Schuster (1907), F.D. Adams and A.S. Eve (1907) have shown that radioactivity is not affected by temperatures up to 2500C or pressures up to 2.6 * 10^10 dynes/cm2. The latter corresponds to a depth near 80 km." 2.6e9 dynes/cm2 is 26 kilobars, So the decay rate of Be7 would be speeded up by a factor of 1.0005 under these conditions. One has to ask, how can this kind of reference be construed to support creationism? But that's not what I came to tell you about ... I mainly was interested in the three references to articles by R.V. Gentry: Science Vol. 173, pg. 727 (1971) Science Vol. 184, pg. 62 (1974) Science Vol. 194, pg. 315 (1976) These were given as a counter to Eldredge's claim that creationists hadn't contributed "a single article to any reputable journal". I have always thought this was an irrelevant criticism, but anyway ... The titles are: "Radiohalos: Some Unique Lead Isotope Ratios and Unkown Alpha Radioactivity", "Radiohalos in a Radiochronological and Cosmological Perspective", and, "Radiohalos in Coalified Wood: New Evidence Relating to the Time of Uranium Introduction and Coalification" Curiously, (ahem) no reference was given to: Moazed C., Spector R.M., Ward R.F., "Polonium Radiohalos: An Alternate Interpretation", Science Vol. 180, pg.1272 (1973) What is this all about? Well, radioactive inclusions in rocks form little (~20 microns) halos around themselves due to defects in the crystal structure caused by alpha decay. Most of these are due to uranium and its decay products. You can identify different energies of decay by distinct rings in the halo. Some of these rings are due to polonium, an intermediate decay product of uranium. In some halos, only the polonium halos are evident, but Po has a half life of about 3 1/2 minutes! In his first two articles, Gentry works around to the conclusion that these really are "virgin" polonium halos. Incidentally, these were observed as early as 1917. The "Alternate Interpretation" article states. "Our measurements do not support the polonium halo hypothesis. We cannot definitely rule out the existence of polonium halos, but it appears that there is no evidence requiring, or even firmly suggesting, their existence." Of course, Gentry doesn't agree. In his second article he states: "Cursory examination of this halo type could lead to confusion with the U halo, especialy in biotite, where ring sizes vary slightly because of dose and other effects. However, good specimens of this type are easily distinguished from U halos, even in biotite." Now we have a problem that comes up often in science. A worker comes up with some really startling results that no one else feels inclined to believe. But in science you are not right until proven wrong. It would seem that other workers simply ignored Gentry from this point on. This act gets repeated at the reference level, where critics of creationism such as myself get sent hither and yon looking up this and that, all with the sure knowledge that the creationists have an infinite supply of these pseudo-conundrums and that they will move on to the next one as soon as you answer the last one. Please note that there is never any evidence which "presents a problem" for Creationism! Take these polonium halos, they require that the inclusions were formed out of fresh polonium in a matter of seconds - a requirement that any scientific theory, creationist or otherwise, would be hard put to meet. Gentry states that the problem, "almost defies reason". I guess this is supposed to be evidence that the polonium was inserted miraculously at the creation. But this is not a scientific conclusion. Lew Mammel, Jr. ihuxr!lew
pmd@cbscd5.UUCP (09/01/83)
[from Lew Mammel:]
Last June 22 Paul Dubuc posted an excerpt from "Origins Research" that
responded to Niles Eldredge's book "The Monkey Business: A Scientist
Looks at Creationism". This excerpt contained several references to
Science magazine. I have looked up four of them and would like to
summarize them for interested net.readers.
The first was one of three about pressure changes affecting radioactive
decay rates. (The other two were to other journals) :
Just for the record, let's list the other two again:
Anderson, J. L., "Non-Poisson Distributions Observed During
counting of certain carbon-14 Labeled Organic (Sub) Mono-
layers" Journal of Physical Chemistry, Vol. 76, No. 24 1972.
(pp.3603-3612)
Emery, G. T. "Perturbation of Nuclear Decay Rates" Annual
Review fo Nuclear Science, Vol. 22, 1972 (pp.165-197)
Hensley W.K., Passet W.A., Huizenga J.R. "Pressure
Dependence of the Radioactive Decay Constant of Berylium-7"
Science, Vol. 18, Sept. 21, 1973 (pp. 1164-1165)
These authors report a pressure dependence of the decay constant of
(2.2 +/- .1) * 10^-5 /kbar. Well, question is, what is the relevance
of this to dating techniques? The magnitude of the dependence is extremely
small for the range of pressures found in the earth's crust. In "The Earth"
by Sir Harold Jeffreys, we find the statement (p. 406):
"Schuster (1907), F.D. Adams and A.S. Eve (1907) have shown that
radioactivity is not affected by temperatures up to 2500C or pressures
up to 2.6 * 10^10 dynes/cm2. The latter corresponds to a depth near 80 km."
2.6e9 dynes/cm2 is 26 kilobars, So the decay rate of Be7 would be speeded
up by a factor of 1.0005 under these conditions. One has to ask, how can
this kind of reference be construed to support creationism?
In considering why these refereces were used in the original article I
would like to quote the context of their use:
"On the other hand, I was amazed to see how Eldredge handled the assumptions
associated with the dating process. He offered no justification for
parent/daughter initial ratios or contamination. His main defense was
concerned with decay rates. "Though some laboratory experiments showing
that extremes of temperature and pressure fail to alter decay rates, it is
true that we must make this assumption" (pg.102).
For some of the other laboratories which were able to induce/observe a
decay rate change, the reader may want to consider:"
[The above three references were then cited.]
The issue was not so much the decay rates, but the fact that Eldredge
seemed to ignore creationist arguments against evolutionist assumptions
of parent/daughter initial ratios and the probable effects of contamination
on them. Variation of the decay rate is clearly the weakest link in
the creationists objections to radiometric dating, but the references
do show that the change is possible. Assuming decay rates haven't, or
don't change is based on the assumption that the conditions that may
affect these rates have never existed on earth.
[back to Lew:]
But that's not what I came to tell you about ...
I mainly was interested in the three references to articles by R.V. Gentry:
Science Vol. 173, pg. 727 (1971)
Science Vol. 184, pg. 62 (1974)
Science Vol. 194, pg. 315 (1976)
These were given as a counter to Eldredge's claim that creationists
hadn't contributed "a single article to any reputable journal". I have
always thought this was an irrelevant criticism, but anyway ...
The titles are:
"Radiohalos: Some Unique Lead Isotope Ratios and Unkown Alpha Radioactivity",
"Radiohalos in a Radiochronological and Cosmological Perspective",
and, "Radiohalos in Coalified Wood: New Evidence Relating to the Time of
Uranium Introduction and Coalification"
Curiously, (ahem) no reference was given to:
Moazed C., Spector R.M., Ward R.F., "Polonium Radiohalos:
An Alternate Interpretation", Science Vol. 180, pg.1272 (1973)
I don't find this to be curious at all since the references were only
cited to counter the evolutionist claim that creationists have not contributed
a single article to any reputable journal. The content of Gentry's articles
was not an issue in the review of Eldredge's book.
What is this all about? Well, radioactive inclusions in rocks form
little (~20 microns) halos around themselves due to defects in the
crystal structure caused by alpha decay. Most of these are due to
uranium and its decay products. You can identify different energies
of decay by distinct rings in the halo. Some of these rings are
due to polonium, an intermediate decay product of uranium. In some
halos, only the polonium halos are evident, but Po has a half life
of about 3 1/2 minutes!
In his first two articles, Gentry works around to the conclusion
that these really are "virgin" polonium halos. Incidentally, these
were observed as early as 1917. The "Alternate Interpretation"
article states.
"Our measurements do not support the polonium halo hypothesis. We
cannot definitely rule out the existence of polonium halos, but it
appears that there is no evidence requiring, or even firmly suggesting,
their existence."
Of course, Gentry doesn't agree. In his second article he states:
"Cursory examination of this halo type could lead to confusion with the U
halo, especialy in biotite, where ring sizes vary slightly because of
dose and other effects. However, good specimens of this type are easily
distinguished from U halos, even in biotite."
Now we have a problem that comes up often in science. A worker comes
up with some really startling results that no one else feels inclined
to believe. But in science you are not right until proven wrong. It
would seem that other workers simply ignored Gentry from this point on.
In science you are not "right until proven wrong"--especially if being
right contradicts evolutionary theory. Scientist have indeed tried to
ignore Gentry. It also seems that his National Science Foundation
Research grant was not renewed because of his stand on creation issues.
Gentry is considered by scientists (evolutionists or otherwise) to be
and expert in his field. He presented his work at the June 1982
AAAS Symposium. It seems scientists there were hard put to refute
his work and many had to acknowledge that Gentry is a true "emphirical
scientist" (Origins Research Vol. 5 No. 2, Fall-Winter 1982). Perhaps
they didn't know about the reference you cited above. :-)
This act gets repeated at the reference level, where critics of creationism
such as myself get sent hither and yon looking up this and that, all
with the sure knowledge that the creationists have an infinite supply
of these pseudo-conundrums and that they will move on to the next one
as soon as you answer the last one. Please note that there is never
any evidence which "presents a problem" for Creationism!
I'm sorry if I goaded you into considering Gentry's work, Lew. But I
found it interesting that you found nothing wrong with Gentry's work--
just that many scientists do not support it. I could have told you that.
I don't think you have really "answered" this one here. The statement
you make in your last sentence is indeed a foolish one, but it is not
advanced or supported my the majority of creationist scientists. When
evolutionists are willing to openly face up to the many problems with
their theory, I, at least, will be satisfied.
Take these polonium halos, they require that the inclusions were formed
out of fresh polonium in a matter of seconds - a requirement that any
scientific theory, creationist or otherwise, would be hard put to meet.
Gentry states that the problem, "almost defies reason". I guess this
is supposed to be evidence that the polonium was inserted miraculously
at the creation. But this is not a scientific conclusion.
In other articles, Gentry has stated that the only explanation for
this evidence was that the minerals in which the polonium existed were
formed extremely quicky; in a matter of seconds, not many millions of
years.
Articles explaining Gentry's work and it's relationship to origins
as well as articles critically examining radiometric dating have appeared
in Origins Research. I may submit summarys of them to the net if time
and interest permit.
If anyone would like a copy of the article Lew is responding to here
I still have it on disk. I will mail anyone who wants one a copy,
or resubmit it if there are a lot of requests.
Until next week.
Paul Dubuc