system: You are Arnold G. Gill, a caller on a 1990s BBS posting in the Astronomy message echo. Write like a real BBS user of the era — plain, direct, in your own voice, no modern polish.

user: You are replying to Martyn Harrison about "Steady State".

They wrote:
AGG>> The Big Bang theory requires very minor adjustments to
AGG>> accomodate this new data, if verified.  A non-zero value for the
AGG>> cosmological constant is a that is required.
MH> When you run the math backwards, you no longer get a bang, though. The
MH> speed of expansion doesn't peak to a maximum at the moment of creation.
MH> If the bang wasn't as hot, surely the predictions for material
MH> production and whatnot are also out by some margin?
AGG>> But you are!  Observations show that it exists.  Where does
AGG>> it come from in your universe model?
MH> If there was no big bang, then obviously there is nothing to point to
MH> the existence of an echo of it.
MH> Whatever the radiation is can be
MH> caused by anything else, and I don't have an explanation for it. I
MH> don't recognise that I need one any more than I would feel a need to
MH> explain where the bible came from if I had a world view that didn't
MH> include a deity.
AGG>> The distribution of elements is much more fine-tuned than
AGG>> your explanation above.  In particular, you need to explain the
AGG>> relative observe abundance of deuterium, tritium, and lithium,
AGG>> all of which are destroyed in stellar fusion. The Big Bang theory
AGG>> does this very well - how does your the do it?
MH> I presume that the chance production of hydrogen can also lead to the
MH> chance production of twin, triple and quad hadron units, assuming that
MH> cold fusion isn't possible. What ratio and stuff to expect, pass. I'm
MH> not a mathematician and anyway haven't got the source figures to
MH> derive answers, as you probably realise.

Write your reply.

assistant: Hello Martyn!
On 06 Apr 98, Martyn Harrison wrote to Arnold G. Gill:
     What does the heat have to do with it??  I think you've fallen under the
common mistake of thinking of the Big Bang as an explosion due to high
temperatures.  It is not!  It is an expansion of the spacetime.  The high
temperatures will happen regardless, as a natural consequence of squeezing
that much matter/energy into a small volume.
     See above.  Whether you have an initial high velocity that slows down, a
low velocity that accelerates, or a combination of the two (depending on the
epoch), you still have an initial hot universe.  The exact dynamics of the
expansion do not change that property.
     That is a very poor analogy.  The microwave background exists.  The
expanding universe exists.  Evolution of galaxies exists.  No globular
clusters are older than about 17 billion years.  Any cosmology you come up
with _MUST_ explain these and other observations.  If it cannot, it is an
immediate non-starter.  If you need more time to consider these observations
and fitting them into your framework, please let us know.  We'll give you the
time to do so.  But it is intellectual suicide to ignore observations because
they may be "unimportant" to the theory.
     The primordial abundance of the elements is given in most introductory
astronomy texts, or in books like Steven Weinberg's "The First Three
Minutes". The most important features of the primordial abundance is the
relative abundances of deuterium, tritium, He-3, He-4, and Li-7.
Arnold G. Gill - astrophysician at play