I have some question that might be hard for me to phrase clearly, but I'm going to give it a try.(adsbygoogle = window.adsbygoogle || []).push({});

So, as far as I understand it, according to GR gravity is a side effect of the way mass (or mass energy, or whatever) curves space-time. So that when an object "falls" to the Earth, it isn't really being attracted to the Earth, but is just moving in a "straight line", which the Earth is also doing, and these lines (geodesics, right?) meet back up in such a way that it looks like the object is being attracted to the Earth.

Am I understanding this, more or less, so far?

It seems to me that if this understanding is correct, then it must mean that everthing is moving really fast through space-time initially, right? I mean, it wouldn't matter if space was curved in such a funky way by itself, unless everything was moving with some serious speed to start with. If this is true, does this mean that everything has kinetic energy from this base movement?

A related question, is this base movement just universal expansion? Is that possible? Though if that's true, what would that mean if the universe started to slow down? And I seem to remember that gravity itself effects expansion, so that can't really be right, can it?

And a final question, if the attraction of gravity is just from bending of space time and geodesic movement, why does it cause acceleration? Or is that not something can be "visualized" in a meaningful way and just comes out of the math?

Thanks for any and all help.

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# GR curved space KE and stuff

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