>>11426509>force>edgelol
In a general sense "gravity" is causing the expansion. it's just that usually people think of gravity as being the attractive kind that comes with mass. General relativity basically says the matter/energy content of the spacetime causes it to curve. There is a big fancy equation called the Einstein field equation which states this.
Locally speaking, yes, the gravity of a black hole is stronger than the expanding universe, but that's not the point. The expanding universe comes from the solution to the aforementioned field equation when one considers the "cosmological principle" (very important, look it up). The universe is very large, the effect of a single black hole anywhere drops off like inverse square distance. So you can see the problem there, once you get so far out it is basically nothing. The reason why this is not the case for the entire universe as a hole is because it is essentially just a big average over a roughly homogenous and isotropic universe.
Repulsive effects in the gravitation are, in this era of the universe, caused by "dark energy". That is the mystery, but the math works out and it confirms what we have observed. In cosmology, it requires dark energy to have a constant energy density for all time, regardless of the size of the universe. Think about that, even as the universe grows larger the dark energy does not grow weaker. Everything else does, however.
