Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: RobC on 12/06/2018 20:09:03

Title: Which force is stronger...gravitation or dark energy?
Post by: RobC on 12/06/2018 20:09:03

Galaxies collide but the expansion of the universe accelerates. This appears counterintuitive like a lot of cosmology and quantum mechanics.

Title: Re: Which force is stronger...gravitation or dark energy?
Post by: Janus on 12/06/2018 21:52:56

Which is stronger depends on the circumstances.  Dark energy has a uniform density, while gravity depends on the amount of mass and the distance from it.   The more you concentrate mass, the stronger the local gravity.   When it comes to things like stars, galaxies and even clusters of galaxies, the mass density is still enough for gravity to dominate.  At scales larger than this, the overall density is low enough that dark energy dominates.