Radioactivity and Absolute Zero
Name: Kevin R.
Would radioactive decay cease at absolute zero? I know that
temperature has no effect on decay rate, but at such a low
temperature wouldn't something intervene that would cause decay
to not be possible?
At absolute zero, atomic and molecular motions (vibration, rotation, and
translation) cease. Electrons continue to orbit atomic nuclei. Radioactivity
is related to an unfavorable neutron-to-proton ratio in an atom. Temperature
has no effect on the ratio. Thus, it has no effect on the rate of
(likelihood) of radioactive decay.
In general the processes that cause radioactive decay do not depend on
temperature, as we typically define temperature, which is a measure of the
thermal motion of atoms and molecules in solids and liquids as a whole.
Radioactive decay is determined by processes occurring within the atomic
nucleii of which we have only statistical knowledge.
It should also be pointed out that it is not possible to achieve 0 kelvin,
even though it is possible to achieve temperatures very, very close.
There are certain chemical reactions that are induced by radioactive decay.
One such reaction is the Szilard-Chalmers reaction. In those cases, one
could see a temperature effect, but that is an effect on the chemical
reaction, not the fundamental nuclear decay process.
Also radioactive decay has been observed at very high temperatures and until
the temperature reaches a point that nuclear reactions occur, the rate of
decay is independent of temperature.
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Update: June 2012