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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 |
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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. |
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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 -------------------------- |
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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 |
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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 |
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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. |
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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. |
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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 |
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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 |
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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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