[extropy-chat] Qualia Bet.

[Robert Bradbury]

Adding to Amara's comment...

Since we are detecting supernova's out to 10+ billion light years, it is
clear that the heavier elements synthesized through the r&s-processes that
Amara points out have been around in the Universe for quite some time
(probably 2+ times the age of our solar system).  The creation of elements
heavier than iron through the r(rapid)-process comes from stars which go
supernova while the evolution of those elements derived from the
s(slow)-process takes place in lower mass (< 8 M_sun) stars.  But the lower
mass stars which are quite abundant today are going to take some time
(billions of years) to build up large quantities of s-process elements.
Most stars which we see *are* evolving relatively large quantities of C/N/O
as they are essential elements in the natural fusion processes that take
place in stars.  Of course these are only distributed into the galaxy to
seed other stars/solar systems late in stellar lifetimes when they go
through red-giant or nova/supernova phases.  So C/N/O as well as heavier
elements largely came from stars similar to or heavier than our sun in mass
which "died" billions of years ago.  The discussions which are interesting
are what are the minimal element abundances necessary on planets for life to
evolve.  I'll always toss into the mix that it seems that evolution (nature)
is clever enough to work around most constraints with respect to element
abundances so long as there is carbon around and you have temperatures which
can allow the formation of complex carbon based structures.  Worth noting is
that carbon is one of the more abundant elements in the universe (after you
discard H & He).

Robert
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