Urwrongx1000 wrote:Momentum, I think the better way to understand Relativity is to imagine that the object is not moving, but instead the environment is moving
I don't think that answered my question.
Momentum is what you have when movement is already under way. But what I am asking is
what began the movement.
If you could place two steel balls close to each other far out in space and then quickly backed away, Newton would say that a "gravitation force" would cause the balls to start moving toward each other and eventually touch.
There seems to be no explanation concerning where that force comes from other than "it just is what it is". And I am not disputing that. I am asking instead what relativity claims to be the cause of the balls to
start moving toward each other and eventually touch. A different perspective of the scene doesn't tell me anything about why the movement began or ended with balls actually touching.
I am asking this because James proposed what seems like a valid theory as to where that "gravitational force" came from - why it exists at all. But I don't know if he is agreeing or disagreeing with relativity. Does relativity even address the question at all?