Re: Origins and Mental Activity

In article <p679i3dc32d0sgfcjcvtuacir6licahua6@xxxxxxx>,
Zoe <muze10@xxxxxxx> wrote:
I would like to work with the current understanding of the Big Bang
activity before continuing to chew on the laws of intelligence.

Taking it for granted that there is no certain answer as to how the
elements formed after the big bang -- except maybe helium and hydrogen
-- but that they most assuredly made their appearance eventually
(maybe from supernovas), I would like to work from that point on.

Okay, so here we have some basic elements distributed randomly
throughout the universe, and in great quantity. Space would look
something like this, multiplied many many times over, I guess?

As explained many times, but repetition seems needed, no.

Let us start from the other way around. We observe that the
universe is expanding -- all points are separating from all other
points. We can then ask what happens if we look backwards in
time -- our expectation is, first, that points would be getting
closer together. From elementary physics, we know that if you
stuff things (gases in particular, and they are most of the
observable matter in the universe) closer together, they heat up.
We can take this elementary bit of physics back to a point where
the temperature of the universe would be, instead of the current
3 K, about 3000 K. At such temperatures (a bit cooler than the
sun's observable 'surface') hydrogen is fully ionized and opaque
to radiation (at least if densities are heigh enough, which they are
for the early universe).

We can continue running the universe back in time, if using
less obvious physics. We continue to compress the universe and
its gas (whatever it may be) until it reaches stellar core
densities and temperatures. At that point (we're approaching from
the cold side, remember, the modern side) fusion of hydrogen to
helium is efficient. As we pass this point (going away from the
present), the cores get hotter and denser -- so hot and dense that
heavy elements, like oxygen and carbon -- are knocked apart in
the collisions at least as fast as they're assembled by fusion
processes. Much before that and there aren't nuclear particles
to worry about. In any case, the outcome of this stellar core
stage in the universe's history is that it erases anything larger
that might have been formed in the earlier history and leaves us
with only a (computable, and observed) distribution of hydrogen,
helium, and a trace of lithium.

All elements heavier than that (perhaps a nod need be taken for
vanishing quantities of beryllium) are distinctly _not_ uniformly
distributed through the universe. They are all produced from
stellar cores and distributed by novae and supernovae. Neither the
location of stars nor distribution of such eruptions is random in
space. Stars, for instance, are far more common inside galaxies
than outside, and galaxies are far from uniformly distributed.
Further, galaxies themselves evolve. New stars (such as our
sun) are formed from the ashes of old stars. This happens with
greater frequency where there are more (and larger -- so as to
produce supernovae) stars. So much more frequent towards cores
of galaxies, or the arms of spiral galaxies.

Now wait a while after the bang for some heavy elements, like
oxygen, carbon, etc. to get formed and blasted into the interstellar
medium of a galaxy of interest. The overwhelming majority of atoms
are _still_ hydrogen and helium. The novae and supernovae lend only
a trace (by mass, even smaller by number) of heavy elements to
the clouds.

Let's jump ahead and consider a real cloud. (This is several
steps ahead of where you are.) Real clouds (I'm selecting, by
the way, the ones most relevant) are cold, relatively dark due to
shielding by dust grains and ice particles, and still essentially
vacuum density. Certainly a better grade vacuum than we generate
here on earth in labs. Cold means 10-100 K, which we can match in
the lab.

What kinds of things happen inside this cloud? Well, the hydrogen
was long since largely locked up in H2 molecules (as the cloud cooled).
But let's ignore that and consider (reality notwithstanding) all
atoms to be solo. Consider a billion atomic mass units at a time
(c.f. http://www.orionsarm.com/science/Abundance_of_Elements.html)
93% are hydrogen atoms, with most of the rest being Helium. As
I said, only a trace of other things are tossed into the mix. So
mostly what goes on in our atomic cloud is that hydrogen atoms bounce
into hydrogen atoms. If they're moving fast enough, they 'stick'
and become an H2 molecule. If they're moving too fast, they bounce
off each other (possibly ionizing one of them). And if they're moving
too slowly, they, again, just bounce off each other. If they
(or anything else) bounce into a helium, they bounce off. Ditto
heliums meeting heliums.

The 'fast enough' qualifier means you have to study chemistry
if you want to understand what's going on in any more detail.
The topic involved is reaction kinetics and/or thermodynamics.

Among those trace of heavy elements, the same rules apply.
If they collide with something which it is chemically permissible
to combine (an O and and H) then they combine with a probability
related to the conditions (pressure, relative velocity, possible electronic
excited state in a participant) of the collision. This also
applies to collisions between the H2 molecules and the still-bare
(in our conceptualization) heavy atoms. In an astrophysically
short time, the H atoms combine to H2 molecules.

Heavy elements molecules build up more slowly. Particles build
up when/where it's easy to simply stack yet another molecule on
to a structure -- as for H2O or CO2 ice, which are fairly happy
under astrophysical conditions to glom on to each other. Once there's
a shield of these, reactions can occur untrammeled inside the cloud.
Low temperatures follow, which slows things down, but this is
balanced by the increased density, and there being no photo-disruption
of the molecules by outside stellar light.

As mentioned earlier, quite an array of molecules have been
found in space, particularly the Great Nebula in Orion (relatively
close and easy to observe).

None of this is instantaneous, none of it is an 'absolutely only
one thing can possibly happen', notwithstanding your malicious misreading
of people to that effect. Kinetics is statistical. Certain outcomes
are more likely, and occur at rates depending on their conditions.
Change the conditions, and different things are more likely. Given
a universe of clouds to run reactions in, quite a few things are
liable to happen.

More, perhaps, to the point, is that the gas cloud has limited
relevance to concerns of forming terrestrial life. We don't live
in giant molecular gas clouds. We live on a planet, whose formation
involved a different seriously non-random process* -- forming a
locale in the universe where astrophysically very minor elements,
like silicon, oxygen, carbon, iron, etc., were made vastly more
common than hydrogen and helium. Further, to form a locale wherein
gas was not the dominant phase of matter, instead setting up a
three phase system where gas, liquid, and solids could interact
physically and chemically.

*Solar system formation, that is. Gravity, thermodynamics, and
chemistry suffice, however, to construct earthlike planets. (And
the more common non-earthlike, of course.)
--
Robert Grumbine http://www.radix.net/~bobg/ Science faqs and amateur activities notes and links.
Sagredo (Galileo Galilei) "You present these recondite matters with too much
evidence and ease; this great facility makes them less appreciated than they
would be had they been presented in a more abstruse manner." Two New Sciences

.

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