I'm asking purely from a mathematic point of view - How would the front and back of the big bang appear in a 3-sphere universe?
In particular, if the big bang is thought of as a 2-sphere and if we assume the universe is $\Bbb S^3$ rather than something akin to $\Bbb R^3$, how would this affect the appearance of the big bang?
I know that if one stands far enough back in $\Bbb S^3$ you can see the back of a distant 2-sphere. How would this make the big bang look and, with other reasonable assumptions, can you derive a mathematical contradiction from the hypothesis that the CMB cold spot is the front of the big bang, and the microwave background emerged from its distant side?