help me build a galaxy

brucep, thanks, I will watch the video when I have time. The 'Black hole FIRST "idea is new to me, and :
Is there a big difference between the shell theorem and an equivalent "DISK" situation?
I hope more readers will find this, your help fascinating.

 

Log in or Sign up to hide all adverts.

The three proto-type galaxies, sphere, disk and barred of even density have interesting different gravity gradients.
The shell max at the perimeter to zero in the center,
the disk with even (unity) from perimeter to the center, with sudden zero dip there, and
the Barred entity from zero in the center to a sudden rise and falling to infinity in the infinite distance.
matter distribution when going from shell to disk?

 

Log in or Sign up to hide all adverts.

Dark matter does not interact with itself, is it perhaps an artifact of the ignored shell theorem?

 

Log in or Sign up to hide all adverts.

First of all the shell theorem is not ignored, I would venture to say that everyone who has taken physics has worked out a problem like that for homework!
What do you mean that dark mater does not interact with itself? The gravity of dark matter effects dark matter as well as normal matter. How would the shell theorem play into this?

 

0rigin please look at bbc "dark matter flits through collisions", Science news daily: : "dark matter darker than thought". if dark matter shows no gravity reaction by interacting with itself, it acts like non-matter inside a shell with zero gravity at the center , and out.

 

Even distribution of matter ?

 

That would be an absurd assumption. The article you cited did not say that dark matter did not cause or react to gravity.

 

river, the shell theorem and other models in their simplest form use an even distribution of matter as a base, and before hotter and denser region developed, that we see in the background radiation.
origin, did the article not imply that dark matter does not react with itself? and only through gravity can dark matter be detected? I an=m just bringing this up for you learned people to see the connections i hope for.

 

The shell theorem has nothing to do with background radiation.

Well close to that. The article said that dark matter interacted with itself even less than thought.

That is correct, currently this is the only way we can detect dark matter.

 

origin, if the early universe was a finite entity, must not the shell theorem apply to it too? -- and If dark matter mimics the gravity effect of baryonic stuff, but does not do so in a nearly stuff-less environment,(when it is on stage alone) , perhaps the too flat velocity data come from matter reading the script badly, rather than unseen actors? does it not look that dark matter only starts acting in the presence of shiny stuff, ?

 

No the shell theorem does not apply to the universe.

dark matter does not mimic baryonic material it simply has mass like baryonic material.

No.