How many ways can a universe expand? As I understand it, three dimensions originally uncurled with time to produce this seemingly 3 dimensional universe. How does this translate into the changes in the original metric? Could the metric have always been flat and the distance function (metric) gave zero flat distance between points that were zero to begin with and then grew from there in a flat manner? Or would this imply the existence of pre-existing flat diminsions of infinite extent of which the early univerese occupied a small but growing portion? Or were the dimensions curled to begin with so that if you set out in the direction of one of the dimensions, you would soon return to the original spot?