(November 26, 2010 at 9:47 pm)Ashendant Wrote: I never thought that space/time expanded with the big bang, i always thought what expanded was matter/energy with the big bang, doesn't matter curve space/time, or is that it the space/time began to expand because matter expanded, or was the curvature of space/time that expanded with matter...
i'm seriously confused right now
The universe is obviously not flat, we clearly live in a three-dimensional space, and for the universe to be flat we would need to live in a two-dimensional space
No, it's the other way around. Matter expanded because space expanded. One could imagine the distant galaxies that are rushing away from us at near the speed of light as in fact sitting still in space, but space itself is stretching under the combined influence of kinetic energy, gravitational potential energy, and newly discovered dark energy and carrying it away from us.
Universe is not flat and has at least 3 spacial dimensions, When people say universe has a certain shape, they mean how space is stretching would determine whether certain behaviors of objects in space would be best described by a geometry problem solved on one of the following: a plane (flat), on a sphere (closed) or on a hyperbolic surface (open). They don't mean space has any shape corresponding to normal human notion of shape.
