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Old February 23rd 09, 05:43 AM posted to sci.astro,sci.physics,sci.physics.relativity
xxein[_2_]
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Default Questions on the enigmatic rotational curve of spiral galaxies

On Feb 22, 7:03*pm, "Robert Karl Stonjek"
wrote:
wrote in message

...
On Feb 22, 7:11 am, "Robert Karl Stonjek"
wrote:

I just want to add a thought experiment to help us visualise what is being
suggested/asked.


Consider a number of stars arrayed in a line across space, say a few light
years in length.


Assuming the initial condition is one of a stationary motion


"stationary motion"?

AHAHAHAHAHAHAHAHA

Tom Davidson
Richmond, VA

RKS:
OK, I was thinking of writing either 'stationary' or 'no motion' and ended
up with an insane hybrid.

Thanks for pointing out the error (I think...)

Robert


xxein: You may be overlooking a serious problem. I was thinking of
the different galaxial types and began wondering if age is a major
factor. Elliptical becomes more disk-like, spiral, bar and then to
ring.

But more interesting is how the gasses and stars revolve at the top or
bottom of the (early?) elliptical ones. Definitely not any
classically described revolution.

So a thought came to me (inspired by your bars). What guides these N
and S stars to form and retract toward the hub and/or rotational disk
(flatten out)?

I know there are a lot of parameters to form galaxies in the first
place, such as the local richness of matter and how it can deviate
from the overall universal expansion radial and a few other things.

But (back to your bars), these top and bottom (N and S) stars and
gasses must feel the presence of each other's position and motion in
such a spherical primordial stage of a galactic formation.
Imperfections give the galaxy a starting rotational velocity and the
rest is the evolutionary history.

Sounds a little too easy. I know. But it all ties into the halo
effect. Halo stars are the oldest associated with any galaxy. They
simply existed in an imperfect group caused also by imperfection in
the distribution of primordial matter. By their position and gravity
they can form discriminant gravitational groups over time. They can
cause an internal gravitational lensing effect. It depends on the
difference in scales between available matter and where they formed.
This difference need only tip a delicate balance. Energy seeks an
equilibrium. It almost never achieves this because of motion. Within
a raggedy group of halo stars, there is originally made a sort of
vacuum deficient of energy because the halo's aggregate gravity was
pulling the energy out. As the halos grew with energy, they shrank
toward each other and pulled more energy in from the outside. Since
they hardly constitute a continuous spherical shell, they continuously
infused their rough interior with more and more non-captured/consumed
energy. So the energy (matter) began to become more dense in the
interior and a galaxy could eventually form by being so entrapped.

Sound better? I don't know if there are halo stars associated with
every galaxy formation. Maybe they got swept into the galaxy itself
and are hard to find or got assimilated to the core/BH during the
evolution of the galaxy. Beats me.

But if halo stars are associated with galaxy formation, they will
appear to remain outside of them in earlier stages of a galaxy's life.

Back to the revolution of stars and an early galactic morphology, if
you simply consider any radian as a 'bar', the diffuse gravitational
effects are very important since the galaxy is building a rotational
momentum.

An additional factor (just considered) is that it is at the galactic
level in cosmology the universal expansion effects first appear. This
prompts me to think of what happens to a galaxy that has insufficient
energy in it's environment to run itself. When a star has to fall
back into itself, it can mean one of three things (the three bears
tale). It has grown to big and too fast for it's britches because of
rich environment (Super-nova type), it becomes a BH because it
maintains a not-so-large feeding schedule or it collapses of
starvation (nova). Neither of these may necessarily be really true,
but it got me to thinking what primordial galaxies would do if cut off
from outside energy. Would they eventually collapse into their
centers and give us quasars? Maybe they met with other universes and
got too hot to handle like a super-fed galaxy. Would we see the same
galaxy as a quasar if we were viewing it from the other universe(s)?
Never mind.

Now maybe with my reply and your 'bar' effect you can show how the
Pioneer anomaly works.