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Are galactic stars spiraling inwards?
Has there been any research on the effects of interstellar gravitational attraction that would make collective star motion in a galaxy behave more like a solid disk? I understand rotational velocity has been observed to be higher than expected for stars farther from galaxy centers. This doesn't agree with Newtonian physics in which Pluto goes around the Sun more slowly than Mercury.
An explanation for the faster star motion observed in galaxies was created and called dark matter. This seems to not comply with Occam's Razor, where the most simple possibility is probably right. I visualize the attraction between stars as stiffening the collection, or increasing the viscosity of the rotational behavior which could explain faster rotation towards the outside of a galaxy. The rotation would behave somewhere between atoms locked together in a frisbee, and a fluid circling the drain. Has any research been done to prove this wrong?
