Ok, The universe is, for the sake of definition, a sphere. In the same way that a baloon pops, and sounds radiates spherically, when the big bang occured, matter was ejected in a roughtly spherical manner. Due to Red shift, we can tell that the universe is indeed expanding. Thus, we're still moving away from the core of the explosion. That was a big fucking explosion. Question is, what is the universe expanding into? If you were blowing up a balloon , it could be said that the balloon is expanding into the air in the room. What is outside the universe?
And, about Time, it isn't man made. It's defination and quantification are, but the dimension of time (the 4th), is not man made. It's a real thing that we move through at a rate which is dependant on our speed and proximity to a gravitaional field.
Antoher question I have is, that in school we're taught that sound is a wave. It have peaks and troughs. My question is, how is that possible! Sound radiates spherically! Try to picture a spherical wave, not a ripple, but of with a predicatable, even frequency. GOOD LUCK! One answer I've found for that one so far is that the idea of a wave is just as close as we're able to come to defining it's properties.