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Questions on the enigmatic rotational curve of spiral galaxies



 
 
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  #11  
Old February 23rd 09, 01:26 AM posted to sci.astro,sci.physics,sci.physics.relativity
Robert Karl Stonjek
external usenet poster
 
Posts: 196
Default Questions on the enigmatic rotational curve of spiral galaxies


"Ian Parker" wrote in message
...
On 22 Feb, 19:52, Eric Gisse wrote:
On Feb 22, 7:27 am, Ian Parker wrote:





On 22 Feb, 13:40, "Robert Karl Stonjek"
wrote:


Thanks, Ian,
The simulations are a little to big but the paper search is more
interesting. For instance in The method of Galactic

Rotationhttp://adsabs.harvard.edu/abs/1996A&AS..118...59J
the authors assume an instant propagation of gravity and the

gravitational
pull of the galactic arm itself appears to be left out altogether.


There is always the question about the validity of assumptions.
Instantanious travekl for gravity can be defended on the basis that
the errors in that approximation are of the order of rotation
velocities relative to c.


Now the Sun is travelling at 600km/s c = 300,000km/s. Hence the
instantaneous travel of gravity can be justified. The velocities of
the stars relative to each other are lower still.


Uh, no. Gravitational effects travel exclusively at c in GR, and this
has been shown to be consistent with reality in observation.

I never said they did not. What I DID say was that the error involved
is proportional to relative velocities/c. (assuming travel at c). If a
lot of calculation is involved you may assume instantaneous travel for
orbital velocities of 600km/s and relative velocities lower still.

- Ian Parker

RKS:
If gravity effects travel at c and the Milky way is 100,000 light years
across then at the outer edge the gravity from the centre of the galaxy
takes 50,000 years to reach the outer edge. That is no problem because the
gravity is uniform. But the pull of the object on the central hub also
takes 50,000 years, and in that time the object has moved.

If I imagine a two dimensional spacetime sheet between a very massive object
such as the centre of the galaxy and a less massive object at a great
distance, such as the sun, then I would expect to see a trough between the
two where the sun's gravity meets the central objects gravity. For an
instant gravitational effect this trough would lead in a straight line
between the sun and the centre, but for a gravitational effect at c we would
expect it to form a helical groove.

Is the sun attracted to the lowest point in this two dimensional space-time
sheet and if so, wouldn't that lowest point be at an angle other than that
of an instantaneous gravity model?

What I am thinking here is that the sun tugs on the centre of the galaxy no
matter how big the difference in the two masses, so the sun must make a dent
in space time all the way to the centre of the galaxy - straight from the
sun to the centre in an instant gravity model but helically in a delayed (by
c) gravity model.

But it might make no difference at all, hence I ask

Robert


  #12  
Old February 23rd 09, 06:43 AM posted to sci.astro,sci.physics,sci.physics.relativity
xxein[_2_]
external usenet poster
 
Posts: 33
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.
  #13  
Old February 23rd 09, 11:09 AM posted to sci.astro,sci.physics,sci.physics.relativity,sci.physics.particle
Y.y.Porat
external usenet poster
 
Posts: 25
Default Questions on the enigmatic rotational curve of spiral galaxies

On Feb 22, 2:11*pm, "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 of each star
relative to the other, what would we expect to occur next?

I assume that the mutual attraction of the stars will cause the row of stars
to shorten until they end up clumped together.

So to make my 'barred' galaxy stable I rotate it fast enough so that the
stars on the two ends don't proceed toward or away from the rotational
centre.

Will this work? *I assume it will not work close to the rotational centre
but will work further out.

There is a greater gravitational pull on objects closer to the two ends
because there is more mass between those objects and the centre, but the
rotational speed is greater as well - nicely balanced

Now we add more mass to the centre. *Objects toward the ends of the arms are
going to be drawn inwardly unless the arm describes an arc. *Now the pull
directly from the central mass can be added to the less effective pull of
the curved arm and the galaxy is again stable.

Why do I think this has been missed?
Models consist of known and unknown quantities, such as the numbers of and
masses of the stars that can be observed. *But unobserved is the central
mass which is estimated. *The central mass, I assume, is estimated at far
higher than it actually is. *I don't think modellers have considered
relatively tiny central masses, as in my barred galaxy model above. *Thus a
higher central mass then requires a greater mass beyond the galaxy for it to
rotate as observed.

I do not have the skills to test these ideas but I assume that either:
It has already been considered and shown to be flawed/viable or
members of this list can estimate the viability of the idea using a
simplified model (as I have suggested above).

Robert


----------------------
look about the 'Circlon' idea !!

ATB
Y.Porat
--------------------------
  #14  
Old February 23rd 09, 12:58 PM posted to sci.astro,sci.physics,sci.physics.relativity
Ian Parker
external usenet poster
 
Posts: 2,554
Default Questions on the enigmatic rotational curve of spiral galaxies

On 23 Feb, 00:26, "Robert Karl Stonjek"
wrote:
"Ian Parker" wrote in message

...
On 22 Feb, 19:52, Eric Gisse wrote: On Feb 22, 7:27 am, Ian Parker wrote:

On 22 Feb, 13:40, "Robert Karl Stonjek"
wrote:


Thanks, Ian,
The simulations are a little to big but the paper search is more
interesting. For instance in The method of Galactic


Rotationhttp://adsabs.harvard.edu/abs/1996A&AS..118...59J



the authors assume an instant propagation of gravity and the

gravitational
pull of the galactic arm itself appears to be left out altogether.


There is always the question about the validity of assumptions.
Instantanious travekl for gravity can be defended on the basis that
the errors in that approximation are of the order of rotation
velocities relative to c.


Now the Sun is travelling at 600km/s c = 300,000km/s. Hence the
instantaneous travel of gravity can be justified. The velocities of
the stars relative to each other are lower still.


Uh, no. Gravitational effects travel exclusively at c in GR, and this
has been shown to be consistent with reality in observation.


I never said they did not. What I DID say was that the error involved
is proportional to relative velocities/c. (assuming travel at c). If a
lot of calculation is involved you may assume instantaneous travel for
orbital velocities of 600km/s and relative velocities lower still.

* - Ian Parker

RKS:
If gravity effects travel at c and the Milky way is 100,000 light years
across then at the outer edge the gravity from the centre of the galaxy
takes 50,000 years to reach the outer edge. *That is no problem because the
gravity is uniform. *But the pull of the object on the central hub also
takes 50,000 years, and in that time the object has moved.

If I imagine a two dimensional spacetime sheet between a very massive object
such as the centre of the galaxy and a less massive object at a great
distance, such as the sun, then I would expect to see a trough between the
two where the sun's gravity meets the central objects gravity. *For an
instant gravitational effect this trough would lead in a straight line
between the sun and the centre, but for a gravitational effect at c we would
expect it to form a helical groove.

Is the sun attracted to the lowest point in this two dimensional space-time
sheet and if so, wouldn't that lowest point be at an angle other than that
of an instantaneous gravity model?

What I am thinking here is that the sun tugs on the centre of the galaxy no
matter how big the difference in the two masses, so the sun must make a dent
in space time all the way to the centre of the galaxy - straight from the
sun to the centre in an instant gravity model but helically in a delayed (by
c) gravity model.

But it might make no difference at all, hence I ask

Look at my posting on the errors. They are in fact less that I have
stated. What travels at c is not in fact gravity, but a kind of
potential tensor. Splitting hairs? Not really, as you say we do have a
uniform field and examining this tensor tells us how accurate we are.


- Ian Parker
  #15  
Old February 24th 09, 04:06 AM posted to sci.astro,sci.physics,sci.physics.relativity
Robert Karl Stonjek
external usenet poster
 
Posts: 196
Default Questions on the enigmatic rotational curve of spiral galaxies

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.

RKS:
On the Halos, I thought I posted a news message on Halos to my Physical
Sciences group but I can't seem to find it. But this paper may be of
interest:


Two stellar components in the halo of the Milky Way
Abstract
The halo of the Milky Way provides unique elemental abundance and kinematic
information on the first objects to form in the Universe, and this
information can be used to tightly constrain models of galaxy formation and
evolution. Although the halo was once considered a single component,
evidence for its dichotomy has slowly emerged in recent years from
inspection of small samples of halo objects. Here we show that the halo is
indeed clearly divisible into two broadly overlapping structural
components-an inner and an outer halo-that exhibit different spatial density
profiles, stellar orbits and stellar metallicities (abundances of elements
heavier than helium). The inner halo has a modest net prograde rotation,
whereas the outer halo exhibits a net retrograde rotation and a peak
metallicity one-third that of the inner halo. These properties indicate that
the individual halo components probably formed in fundamentally different
ways, through successive dissipational (inner) and dissipationless (outer)
mergers and tidal disruption of proto-Galactic clumps.

Source: Nature
http://www.nature.com/nature/journal...ture06460.html

Any search for 'Halo' and one gets numerous hits for 'dark matter halos'...

And when I read up on the unexpected galaxy rotational speeds they always
specify spiral galaxies ~ is the rotational speed of non-spiral galaxies as
expected? When a galaxy goes from spiral to bar to ring does the motion
become more Copernican?

Robert


  #16  
Old February 24th 09, 02:10 PM posted to sci.astro,sci.physics,sci.physics.relativity
jesko
external usenet poster
 
Posts: 43
Default Questions on the enigmatic rotational curve of spiral galaxies

On Feb 22, 1:11*pm, "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 of each star
relative to the other, what would we expect to occur next?

I assume that the mutual attraction of the stars will cause the row of stars
to shorten until they end up clumped together.

So to make my 'barred' galaxy stable I rotate it fast enough so that the
stars on the two ends don't proceed toward or away from the rotational
centre.

Will this work? *I assume it will not work close to the rotational centre
but will work further out.

There is a greater gravitational pull on objects closer to the two ends
because there is more mass between those objects and the centre, but the
rotational speed is greater as well - nicely balanced

Now we add more mass to the centre. *Objects toward the ends of the arms are
going to be drawn inwardly unless the arm describes an arc. *Now the pull
directly from the central mass can be added to the less effective pull of
the curved arm and the galaxy is again stable.

Why do I think this has been missed?
Models consist of known and unknown quantities, such as the numbers of and
masses of the stars that can be observed. *But unobserved is the central
mass which is estimated. *The central mass, I assume, is estimated at far
higher than it actually is. *I don't think modellers have considered
relatively tiny central masses, as in my barred galaxy model above. *Thus a
higher central mass then requires a greater mass beyond the galaxy for it to
rotate as observed.

I do not have the skills to test these ideas but I assume that either:
It has already been considered and shown to be flawed/viable or
members of this list can estimate the viability of the idea using a
simplified model (as I have suggested above).

Robert


The problem is not the mass of the center, but the center itself.
Which is the real center of the cluster?
Which is the center of each star?
Well the center of any star is exactly the center of the ideal sphere
that it is.
The center of the star is not the center of the cluster.
This is just an illusion.
What really moves it is dark matter or the Heaven sphere.
It is difficult to admit , cause one imagine that stars really move
around a center
but stars are fixed. They don't move cause momentum is zero but stars
are massive,
so velocity is zero.
Gravitational theory wil be replaced by the new theory of Dark
Energy.
Dark energy is not local but widespread in all the Universe.



Thanks in advance.
  #17  
Old February 25th 09, 03:00 AM posted to sci.astro,sci.physics,sci.physics.relativity
[email protected]
external usenet poster
 
Posts: 6
Default Questions on the enigmatic rotational curve of spiral galaxies

On Feb 23, 10:06*pm, "Robert Karl Stonjek"
wrote:
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.

RKS:
On the Halos, I thought I posted a news message on Halos to my Physical
Sciences group but I can't seem to find it. *But this paper may be of
interest:

Two stellar components in the halo of the Milky Way
Abstract
The halo of the Milky Way provides unique elemental abundance and kinematic
information on the first objects to form in the Universe, and this
information can be used to tightly constrain models of galaxy formation and
evolution. Although the halo was once considered a single component,
evidence for its dichotomy has slowly emerged in recent years from
inspection of small samples of halo objects. Here we show that the halo is
indeed clearly divisible into two broadly overlapping structural
components-an inner and an outer halo-that exhibit different spatial density
profiles, stellar orbits and stellar metallicities (abundances of elements
heavier than helium). The inner halo has a modest net prograde rotation,
whereas the outer halo exhibits a net retrograde rotation and a peak
metallicity one-third that of the inner halo. These properties indicate that
the individual halo components probably formed in fundamentally different
ways, through successive dissipational (inner) and dissipationless (outer)
mergers and tidal disruption of proto-Galactic clumps.

Source: Naturehttp://www.nature.com/nature/journal/v450/n7172/abs/nature06460.html

Any search for 'Halo' and one gets numerous hits for 'dark matter halos'....

And when I read up on the unexpected galaxy rotational speeds they always
specify spiral galaxies ~ is the rotational speed of non-spiral galaxies as
expected? *When a galaxy goes from spiral to bar to ring does the motion
become more Copernican?

Robert


xxein: Yes. Any inner halo is an after-effect. It will have more
metal and be pro-grade influenced through the interior gasses over
time. The net retrograde of the outer is simply it's primordial
motion and can foster an anti-motion of the interior because of an
attempt of the central gasses to find the equilibrium.

Think about this (even if I did not envision inner halo stars). The
outer halo stars originally have a motion that is almost non discrete
wrt to each other. But some oddball chaos caused them to form from a
differential pressure or collisions. Without knowing the patten of
this genesis, we can't contemplate how they move wrt one another. But
they do form a local region. We would be stupid to say the after
effects would form a square, wouldn't we? Maybe some weird shape as
time went along, but what is the aftermath? It tends to become
spherical.

Now it is an energy sink and when it exhausts the local interior
energy, all that is left is the exterior. Energy is drawn in en mass
(!) and with its own equilibrium function to cope with. If the outer
halo stars have any primordial motion at all, the incoming energy will
be bent by the gravity of each of the outer halo stars. As said, It
is not a continuous boundary. The influx meets a moving gravitational
object. Where does the non-captured energy go?

As it enters he interior of this gravitational circumstance of halo
stars, any movement of the stars themselves can produce an unequal
bending of the energy stream that passed through.

The first thing that happens is that the energy will try to seek an
equilibrium after the gravitational bending. It will tend to swirl
because there is a minimal pressure there that it is filling up at
this point in time. It achieves it's own local rotation. This can
provide for any inner halo stars. But what of the rotation? As the
outer halo star moves and energy passes by it, it provides for a
moving hollow. Which energy do you think will arrive there first?
That is what will control the interior rotation and it will be
opposite.

That sets up the rest of the net interior rotation even before the
inner halo stars can be formed. But they will form first, after the
outers. This is because the rotation has a gravitational center that
holds it together in the first place. Such large swirls dwarf the the
overflow of their extent.

The specific movement of the outers produces the counter rotation of
its first product (the inners). The net rotation of the interior will
be opposite that of the outer halo stars.
  #18  
Old February 25th 09, 04:39 PM posted to sci.astro,sci.physics,sci.physics.relativity
john190209
external usenet poster
 
Posts: 11
Default Questions on the enigmatic rotational curve of spiral galaxies

On Feb 24, 8:00 pm, wrote:
On Feb 23, 10:06 pm, "Robert Karl Stonjek"
wrote:



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.


RKS:
On the Halos, I thought I posted a news message on Halos to my Physical
Sciences group but I can't seem to find it. But this paper may be of
interest:


Two stellar components in the halo of the Milky Way
Abstract
The halo of the Milky Way provides unique elemental abundance and kinematic
information on the first objects to form in the Universe, and this
information can be used to tightly constrain models of galaxy formation and
evolution. Although the halo was once considered a single component,
evidence for its dichotomy has slowly emerged in recent years from
inspection of small samples of halo objects. Here we show that the halo is
indeed clearly divisible into two broadly overlapping structural
components-an inner and an outer halo-that exhibit different spatial density
profiles, stellar orbits and stellar metallicities (abundances of elements
heavier than helium). The inner halo has a modest net prograde rotation,
whereas the outer halo exhibits a net retrograde rotation and a peak
metallicity one-third that of the inner halo. These properties indicate that
the individual halo components probably formed in fundamentally different
ways, through successive dissipational (inner) and dissipationless (outer)
mergers and tidal disruption of proto-Galactic clumps.


Source: Naturehttp://www.nature.com/nature/journal/v450/n7172/abs/nature06460.html


Any search for 'Halo' and one gets numerous hits for 'dark matter halos'...


And when I read up on the unexpected galaxy rotational speeds they always
specify spiral galaxies ~ is the rotational speed of non-spiral galaxies as
expected? When a galaxy goes from spiral to bar to ring does the motion
become more Copernican?


Robert


xxein: Yes. Any inner halo is an after-effect. It will have more
metal and be pro-grade influenced through the interior gasses over
time. The net retrograde of the outer is simply it's primordial
motion and can foster an anti-motion of the interior because of an
attempt of the central gasses to find the equilibrium.

Think about this (even if I did not envision inner halo stars). The
outer halo stars originally have a motion that is almost non discrete
wrt to each other. But some oddball chaos caused them to form from a
differential pressure or collisions. Without knowing the patten of
this genesis, we can't contemplate how they move wrt one another. But
they do form a local region. We would be stupid to say the after
effects would form a square, wouldn't we? Maybe some weird shape as
time went along, but what is the aftermath? It tends to become
spherical.

Now it is an energy sink and when it exhausts the local interior
energy, all that is left is the exterior. Energy is drawn in en mass
(!) and with its own equilibrium function to cope with. If the outer
halo stars have any primordial motion at all, the incoming energy will
be bent by the gravity of each of the outer halo stars. As said, It
is not a continuous boundary. The influx meets a moving gravitational
object. Where does the non-captured energy go?

As it enters he interior of this gravitational circumstance of halo
stars, any movement of the stars themselves can produce an unequal
bending of the energy stream that passed through.

The first thing that happens is that the energy will try to seek an
equilibrium after the gravitational bending. It will tend to swirl
because there is a minimal pressure there that it is filling up at
this point in time. It achieves it's own local rotation. This can
provide for any inner halo stars. But what of the rotation? As the
outer halo star moves and energy passes by it, it provides for a
moving hollow. Which energy do you think will arrive there first?
That is what will control the interior rotation and it will be
opposite.

That sets up the rest of the net interior rotation even before the
inner halo stars can be formed. But they will form first, after the
outers. This is because the rotation has a gravitational center that
holds it together in the first place. Such large swirls dwarf the the
overflow of their extent.

The specific movement of the outers produces the counter rotation of
its first product (the inners). The net rotation of the interior will
be opposite that of the outer halo stars.


Or- a better explanation and much more sensible:

There are stars in a roughly spherical placement around each
galaxy because the edges of the disc used
to be there, and will be there again.
The disc precesses as well as spins ( the precession
is twice that of the spin)- this sweeps the disc through a
spherical volume as it spins and creates the halo.

Galaxies are spheres over the long run just as
atoms are discs in the short run.

john
Galaxy Model for the Atom
http://users.accesscomm.ca/john
  #19  
Old February 25th 09, 06:20 PM posted to sci.astro,sci.physics,sci.physics.relativity
john190209
external usenet poster
 
Posts: 11
Default Questions on the enigmatic rotational curve of spiral galaxies

On Feb 25, 9:39 am, john190209 wrote:
On Feb 24, 8:00 pm, wrote:



On Feb 23, 10:06 pm, "Robert Karl Stonjek"
wrote:


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.


RKS:
On the Halos, I thought I posted a news message on Halos to my Physical
Sciences group but I can't seem to find it. But this paper may be of
interest:


Two stellar components in the halo of the Milky Way
Abstract
The halo of the Milky Way provides unique elemental abundance and kinematic
information on the first objects to form in the Universe, and this
information can be used to tightly constrain models of galaxy formation and
evolution. Although the halo was once considered a single component,
evidence for its dichotomy has slowly emerged in recent years from
inspection of small samples of halo objects. Here we show that the halo is
indeed clearly divisible into two broadly overlapping structural
components-an inner and an outer halo-that exhibit different spatial density
profiles, stellar orbits and stellar metallicities (abundances of elements
heavier than helium). The inner halo has a modest net prograde rotation,
whereas the outer halo exhibits a net retrograde rotation and a peak
metallicity one-third that of the inner halo. These properties indicate that
the individual halo components probably formed in fundamentally different
ways, through successive dissipational (inner) and dissipationless (outer)
mergers and tidal disruption of proto-Galactic clumps.


Source: Naturehttp://www.nature.com/nature/journal/v450/n7172/abs/nature06460.html


Any search for 'Halo' and one gets numerous hits for 'dark matter halos'...


And when I read up on the unexpected galaxy rotational speeds they always
specify spiral galaxies ~ is the rotational speed of non-spiral galaxies as
expected? When a galaxy goes from spiral to bar to ring does the motion
become more Copernican?


Robert


xxein: Yes. Any inner halo is an after-effect. It will have more
metal and be pro-grade influenced through the interior gasses over
time. The net retrograde of the outer is simply it's primordial
motion and can foster an anti-motion of the interior because of an
attempt of the central gasses to find the equilibrium.


Think about this (even if I did not envision inner halo stars). The
outer halo stars originally have a motion that is almost non discrete
wrt to each other. But some oddball chaos caused them to form from a
differential pressure or collisions. Without knowing the patten of
this genesis, we can't contemplate how they move wrt one another. But
they do form a local region. We would be stupid to say the after
effects would form a square, wouldn't we? Maybe some weird shape as
time went along, but what is the aftermath? It tends to become
spherical.


Now it is an energy sink and when it exhausts the local interior
energy, all that is left is the exterior. Energy is drawn in en mass
(!) and with its own equilibrium function to cope with. If the outer
halo stars have any primordial motion at all, the incoming energy will
be bent by the gravity of each of the outer halo stars. As said, It
is not a continuous boundary. The influx meets a moving gravitational
object. Where does the non-captured energy go?


As it enters he interior of this gravitational circumstance of halo
stars, any movement of the stars themselves can produce an unequal
bending of the energy stream that passed through.


The first thing that happens is that the energy will try to seek an
equilibrium after the gravitational bending. It will tend to swirl
because there is a minimal pressure there that it is filling up at
this point in time. It achieves it's own local rotation. This can
provide for any inner halo stars. But what of the rotation? As the
outer halo star moves and energy passes by it, it provides for a
moving hollow. Which energy do you think will arrive there first?
That is what will control the interior rotation and it will be
opposite.


That sets up the rest of the net interior rotation even before the
inner halo stars can be formed. But they will form first, after the
outers. This is because the rotation has a gravitational center that
holds it together in the first place. Such large swirls dwarf the the
overflow of their extent.


The specific movement of the outers produces the counter rotation of
its first product (the inners). The net rotation of the interior will
be opposite that of the outer halo stars.


Or- a better explanation and much more sensible:

There are stars in a roughly spherical placement around each
galaxy because the edges of the disc used
to be there, and will be there again.
The disc precesses as well as spins ( the precession
is twice that of the spin)- this sweeps the disc through a
spherical volume as it spins and creates the halo.

Galaxies are spheres over the long run just as
atoms are discs in the short run.

Observe this spinning disc precessing at 2 and rotating at 1:
every time the disc precesses 180 degrees it sweeps out
a spherical volume and the next pass through this same
volume it is spinning the *opposite direction*.

http://users.accesscomm.ca/john/standingwave.GIF

THIS is why successive layers of SPHERICALLY-PLACED halo stars
have opposite rotational motion!!!!!

john
Galaxy Model for the Atom
http://users.accesscomm.ca/john

  #20  
Old February 25th 09, 08:57 PM posted to sci.astro,sci.physics,sci.physics.relativity
john190209
external usenet poster
 
Posts: 11
Default Questions on the enigmatic rotational curve of spiral galaxies

On Feb 25, 11:37 am, Sam Wormley wrote:
john190209 wrote:

Observe this spinning disc precessing at 2 and rotating at 1:
every time the disc precesses 180 degrees it sweeps out
a spherical volume and the next pass through this same
volume it is spinning the *opposite direction*.


http://users.accesscomm.ca/john/standingwave.GIF


THIS is why successive layers of SPHERICALLY-PLACED halo stars
have opposite rotational motion!!!!!


john
Galaxy Model for the Atom
http://users.accesscomm.ca/john


Dang Sefton--now YOU broke my bull**** meter!


That's my story and I'm sticking to it.
But it's funny how things like layered
oppositely-spinning spherical halos and jets spewing
lots of energetic particles and galactic discs
that spin all-of-a-piece just seem to
fall naturally out of my story- hey?

john
 




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