But what about the constant rotational velocities in galaxies regardless of the distance from galactic center?

"However, all energy and matter creates gravity, so you’d expect that all that extra stuff would affect how gravity works. Specifically, you’d expect the velocity of orbiting objects to all be about the same, regardless of the size of the orbit (still: not obvious). But, to the best of our ability to measure... show more "However, all energy and matter creates gravity, so you’d expect that all that extra stuff would affect how gravity works. Specifically, you’d expect the velocity of orbiting objects to all be about the same, regardless of the size of the orbit (still: not obvious). But, to the best of our ability to measure (which is pretty good), no effect has been seen at all in terms of the movement of stars and planets and whatnot." [http://www.askamathematician.com/2011/06...

Seems to me there is an example of stars movement that is about the same over most of the radius of spiraling galaxies. And that has not been explained as far as I know. So is this not an example of vacuum energy affecting gravity?
3 answers 3