I'm a layman that loves Physics. I'm also horrible at math. Having said that I have many, many questions in regards to physics and General Relativity in-particular. I will try to keep my question(s) as clear as I can.
In relation to Gravity, Galaxies and The Universe can someone please explain the following:
If the force of gravity within a given galaxy is keeping said galaxy together, as well as "pulling" all objects within it closer (towards the center and/or the Black Hole at the center), how does General Relativity account for the fact that all galaxies are racing "away" from each other, and accelerating faster and faster as they do so?
It seems, (to me at least), that this is a "paradox" of some sort. How can it be that the bodies within a given galaxy are being drawn closer to one another over time due to gravity and yet that whole galaxy is moving away from all the other galaxies in the universe that should, by the laws of G.R., be heading towards one another as well.
I understand a little bit about expansion, the big bang etc. However, this question/paradox has always interested me. Again as a layman it is hard for me to grasp the mathematical reasoning behind all of this, but I am however, good at conceptualizing these phenomena when laid out in a more analogous or geometric fashion.