friesen@psivax.UUCP (Stanley Friesen) (07/18/85)
I will now make a few more comments on the radio-halo
"evidence" from the "116 reasons" pamphlet. At least one person
seems to have misunderstood my response to the evidence of the halos.
My point was that evidence casting doubt on the *calibration* of
a measurement system is *not* evidence against the validity of the
basic premises of that system. An example of this is the intergalactic
distance scale, which is calibrated on the basis of the brightness
relationships of Cepheid variables. A number of years ago it was
discovered that the Cepheids being used for this purpose were about
twice as bright as had been previously believed. This did not
invalidate the use of Cepheids as a calibration factor, it merely
meant that all old distance estimates had to be multiplied by 2!
On the basis of the rather vague and poorlyt written description
of the Polonium halo discrepancy in the pamphlet it seemed to me
that this was the sort of thing that was actually beoing reported,
and as such was *not* evidence against a large age for the Earth.
However, since then I have had a chance to read the articles
by Dr. Gentry refered to in the pamphlet, and to trace down *some*
follow-up articles. The actual problem is that certain radiation halos
in volcanic rocks show evidence of having been produced by a heavy
isotope of the rare-earth metal Polonium, which happens to have a
hal-life of only aprox. 3 minutes! Furthermore Dr Gentry failed to
find any evidence of how these small concentrations of Polonium got
into the rock. Thus if his analysis of the origin of these halos is
correct(and I suspect it is - despite some questions by other workers)
*and* the Polonium was included in the rock from the start it implies
*very* rapid cooling of the rock. Please note, it is *not* the
*existance* of the Polonium that causes the problem(since it can form
from normal radioactive decay of other elements with long half-lives)
but rather it *location* deep inside of the coagulated magma known
as granite. However, at least one worker has demonstrated that under
the right conditions Polonium can diffuse through such rock with
amazing rapidity and collect in small discontinuities. This suggests
that in fact the Polonium inclusions formed *after* the formation of
the rock, thus removing any need for rapid cooling. Unfortunately I
ran out of time at the library before I could follow-up on this
article to see how other workers responded to it, since a single,
unchecked result may often be misleading.
--
Sarima (Stanley Friesen)
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