I'm not a physicist but if the universe has the topological shape of a surface of a sphere or of an ellipsoid (what speaks against this possibility?) and if there happens to be a big bang on one spot and the expansion is fast enough so it does not collapse, the gravitational force should accelerate the expansion "on the other side of the sphere", doesn't it?

"Falls das Resultat nicht einfach nur dermassen gut aussieht, sollten Sie nochmal von vorn anfangen..." - Manual

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