Gravity does more than hold us together. It stretches space-time out. There are multiple dimensions, but our bodies and minds are built to understand three. That's why babies grown in space don't come out "right".
From our point of view, the surface of the earth is really a two dimensional object. If you were to travel in a straight line, you would come back to where you started. When removed from the gravity of earth, we see it as a ball, with people running over it in all possible directions. But on the earth itself, the earth is a map laid out, with the borders of the map wrapping around the world like the sides in Pac-Man. Isn't that really weird?
Does a strong rotation create strong gravity? Or does strong gravity create a strong rotation? It's the latter. It's only at these random points of gravity where life, or anything, could exist. Space-time is the response of nothingness being imposed on by uncle laws of reality? Well what about gravity-time?
The more dense a planet is, the slower time is there. consider a point of infinite dense, its time would be infinitely slow! when the big bang occurred, creation itself rushed outwards. due to laws of physics, points began to gather matter and energy and formed the first stars and galaxies and seeded the rest of the universe with the elements we know. so what is between the matter of creation? the void of space. it seem that time begins to get funny as you leave the gravity of a planet. so when you are outside of all gravity, what affect does time carry? Does gravity create three dimensions? No, I think it tries to bring things to "order"
would the singularity of the big bang be like ultimate paradise or what? what could be more perfect and unifying that being one with all energy in the universe, lol. it makes death by black hole pretty exciting.
the speed of light. nothing is faster than it, and it is relative from all points of view in space. it, is not affected by the void of space. it's speed remains consistent, despite the fact that gravity can "capture" it. hold it in. it is the only thing that is truly 'relative'. we, however, are subject to the effects space has on time. as matter approaches the speed of light, its "mass" increases, and thus it's gravity increases. at the speed of light, any matter would have infinite mass. ie, be everywhere. the stuff that does travel at the speed light all share something common. they have zero mass! so really, maybe having infinite mass is like having zero mass! JUST KIDDING www.newton.dep.anl.gov/askasci…
but it does make the zero mass stuff seem absolutely crucial to the workings of the universe.
if we ever hope to become a star faring race, we seriously need to develop space folding technology and 'hop' through the universe on planets. finding habitable planets that also shared our gravity-time would be really hard, so instead we could point a "portal" device at the planet, set it to orbit, and hop through. if we repeated this, humanity could "stay together" and send knowledge through the portal. otherwise, time dilation will really prevent any sort meaningful contact. it may not be possible to create a portal in gravity-time though, maybe only space-time