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Re: Elements

Why were not they all produced in the so called "big bang"?

Because the universe expanded too fast. The temperature and density of
matter fell below the threshold necessary for further fusion reactions
to take place quite early on before the higher mass elements had a chance
to build up.

David Bowman
dbowman@georgetowncollege.edu

I think I'd say it a little differently, although I haven't done
the calculations myself so I may be a bit off. As I understand it,
by the time the temperature was low enough for any nuclei to stick
together, the density of baryons was much lower than in the centers
of stars. Although the density of baryons was high enough for
two-particle reactions to form helium and a bit of lithium, it was
not high enough for the triple-alpha reaction needed to form
carbon-12 out of helium-4. If beryllium-8 were stable, things
might have been very different.

Besides Ferris (who is only a journalist and doesn't always get his
facts straight), I recommend Weinberg's The First Three Minutes
and, for the brave, Peebles, Principles of Physical Cosmology.

Dan Schroeder
dschroeder@cc.weber.edu