How would the gravitational forces weakening accelerate the expansion speed? It would at best “not slow it down”, you can’t explain the speed increase with this logic. That just sounds wrong. Am I missing something?
Would it be that as gravity weakens, the inertial forces of a spinning galaxy allow it to spread without the gravitational drag that would otherwise slow it down as it expanded?
This is purely my filthy casual’s intuitive take. I’m happy to hear what’s off about it.
I think you mixed up galaxies moving away from each other, and a galaxy’s stars etc. moving in space.
As per Einstein’s relativity theory, gravitational force has infinite range. So there will always be some pulling force between galaxies, which means they would eventually slow down and and eventually start moving towards each other. But our observations suggest that they are moving even faster day by day. So there must be some force that is stronger than gravity and it must be somehow pushing objects.
So gravity by itself doesn’t explain the speed increase of universe’s expantion.
