Dark Matter Halos must be revolving, rotating.

Discussion in 'Astronomy, Exobiology, & Cosmology' started by nebel, Oct 26, 2018.

  1. nebel Valued Senior Member

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    Dark matter* is elusive, but it is detected by the gravitational force it exerts, It must have mass or an exotic, "dark" equivalent. If that is so,
    particles, bodies of dark matter must, to remain permanent fixtures of entities, orbit at the same velocity as other, nearby normal matter objects. any objections?
    * if it exists
     
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  3. James R Just this guy, you know? Staff Member

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    It has mass. That's the main point of it. Gravity is caused by mass.

    What makes you think dark matter is a permanent fixture of an entity? What entities are you thinking of?
     
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  5. nebel Valued Senior Member

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    yes, it has to have Mass, that means it is attracted to the central mass of a galaxy, and requires the appropriate orbital velocity to balance against that inward pull using possibly dark "centrifugal force"
    Those velocity required are already measured on objects at those distances, ergo,
    DM, be it Wimps, cold or hot , of diffuse gas - like consistency, has to move to make a permanent Halo, or sink, or escape.
    I brought this up today at an astronomy lecture's question and answer part, having become aware of this idea, hypothesis logically while looking at his charts, it nearly floored the lecturer, since it touched the very basis of the unknown in DM. He appeared to not have heard of that, or remembered that angle from before.
    I used the word permanent, because if it were not, and not revolving with the normal stuff, it would spiral in or have escape velocity. Stability being one of the touted benefits of DM. so:
    Before it can stabilize galaxies, it has to be stable itself, and rotation will do it every and all the time. thank you.
    Falsification please.

    .
     
    Last edited: Oct 26, 2018
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  7. RainbowSingularity Valued Senior Member

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    yes
    i object on the nature of your polarity to terms of absolute binary quantum theory.

    if i have a wheel, and attached on the outside of that wheel are 2 bicycles.
    each bicycle is being ridden by a person.
    the wheel and the entire eventis inside a frictionless space.
    all moving parts of the bicyles have no latent resistance via friction retardation.

    1 person is pedalling at a steady speed. the other person is pedalling at random intervals and at differing speeds/intensitys.

    the combined equational result of output on the rotational force that is measured of the entire wheel rotating with 2 bicyles, has a total sum of energy.
    is that total sum of energy able to be quantified as a dual colaborative equation based on the total velocity observed of the entire moving wheel ?
    yes ? (the answer should be yes if your lost)

    the next question.
    we know the total output of 1 bicycle
    we know the total output of the entire wheel ? only at the precise moment of measure as it is always speeding up... acceleration = ? times what-ever etc...

    what is the unknown energy output of the 2nd bicyle ?
    you dont know !

    thats my point !
     
  8. origin In a democracy you deserve the leaders you elect. Valued Senior Member

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    What does that mean?
     
  9. origin In a democracy you deserve the leaders you elect. Valued Senior Member

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    He must not have read the wiki article on DM. There is a section on angular momentum of DM.
     
  10. Janus58 Valued Senior Member

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    While DM has mass, which means gravitational attraction, which means that the DM particles of the Halo are in orbit around the mass of the galaxy, This does not mean that it has to orbit in the same way that the visible matter of the galaxy does. The visible matter self-collides. When the galaxy formed, bits and pieces of matter that had widely eccentric orbits or orbited with inclinations tended to collide with other matter all these collisions tended to clean the galaxy up so that we ended up with a disk like structure with everything in the disk orbiting in the same direction and with out too much moving in and out from the center.
    DM does not collide with visible matter or itself. Except for the gravitational attraction two DM particles would pass right through each other as if the other wasn't there. For DM, the mechanism that ordered the orbits of the stars doesn't exist. and a particle can be orbiting at any eccentricity or inclination. A DM particle passing through the solar system could be passing through on it way from a apoapis way out beyond the visible galaxy to to a periapis somewhere closer in towards the center of the galaxy, or orbiting at a different orbital plane or both. The point is that its velocity at that point can be entirely different than that of the solar system.
    The best that we can say that if you took all the DM particles passing through the solar system at any moment, that statistically, their speeds( though not their velocities) would average out to be the same as the solar system.
    While the DM halo keeps it shape as a whole, the DM particles making up any one part of it are constantly moving at different velocities, and the DM particles making up that part is constantly changing. Rather than like birds flying in formation, they are like bees in a swarm (and for that fact, bees that don't have to worry about bumping into each other).
     
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  11. nebel Valued Senior Member

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    That sounds like what one would expect of an elliptical or globular cluster made of neutrinos. Yet ant any given point the DM particle would roughly match that of a conventional object's elliptical orbits speeds. fast at perihelion, and
    slower further out. surprise,
    just 2 days ago that I thought we were embedded in wimps just sitting there motionless.
    It appears there are so many uncertainties about DM, that he was questioned on and bombarded with, that he ducked on that one. thank you all.
     
  12. James R Just this guy, you know? Staff Member

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    Thanks Janus58. I didn't know any of that.
     
  13. RainbowSingularity Valued Senior Member

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    quantum superpositioning...
    = pure mechanics deductive reasoning ?

    how does that get represented as an equation going in either direction ?

    if dark matter creates dark energy which provides an alternating current state of interaction with matter(the creates gravity), then dark matter its self may not have any obvious direct connection to matter ... ?
    just a passing thought.
     
  14. nebel Valued Senior Member

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    That is seconded! excellent! and triggers the second question, with 5 times more dark matter in the universe than our kind, , why do we not see a halo effect in the solar system? Oumuamua had the right direction, but is hardly in orbit or dark enough. ha. Why does that ratio not hold locally? by the looks of it, we seem to have more space per mass than the galactic disk? or do we?
     
  15. Janus58 Valued Senior Member

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    Because all that extra dark matter is very thinly spread out over a very large area.
    Even though it might not seem like it from our perspective, the Solar system is a very dense pocket of matter compared to the overall density of the galactic disk. In turn, the visible matter of the disk is confined to that disk while DM extends into those regions both above and below the disk.
    It is estimated that all the dark matter within the solar system amounts to about the mass of a small asteroid. But even at this low density, the spherical volume closer to the center of the galaxy than the solar system is contains an amount of DM that equals a good fraction of the total mass of visible matter in the galaxy. (and this estimate would be slightly on the low side, as the density of DM is expect to increase by some degree as you move in towards the center of the galaxy. )
     
  16. nebel Valued Senior Member

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    You must be right, because Kepler' laws, that are based on an nearly empty space with a big central mass with orbiting bodies,-- holds here, whereas stars in our galaxy orbit more as if they were in a solid disk. with high velocities at the perimeter.
     
  17. RainbowSingularity Valued Senior Member

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    proportionality of orbital mass(at distance of x=) to velocity = gravity ?
    = constant ?
     
  18. Janus58 Valued Senior Member

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    The stars of the Milky way do not orbit as if the galaxy is a solid disk. The following image shows a rough representation of the observed velocity/distance curve (A), and the predicted curve based on visible matter alone (B). The red line is what you would expect if the galaxy acted like a solid disk.

    Please Register or Log in to view the hidden image!

     
  19. nebel Valued Senior Member

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    Thank you for the correction , . I meant more like a solid disk. would not a curve of the Solar system situation show the opposite of the red line,? could you insert that?
    going cleanly from very high, through 50 km/s (Mercury) and through 5 (Pluto) --to 0 at infinity) and would not the red line start really at zero in the corner?
    The gap between A and B must show the influence of DM?
     
    Last edited: Oct 30, 2018

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