No, I'm imagining an explosion expanding (if you like) and creating its own space as it goes but it's still supposed to have started at a single point therefore some "stuff" must be travelling faster than "other stuff".

No-one can say what the "outer part" of this so-called balloon is or how it's affected by its travel or where it's going.

Seems to me that as everything is revolving or travelling on a curve, one day it'll all be heading back to where it started.

How with the theories theorems cope with that?

I thought a theorem depended on a proven fact but some of the theorems are using theories as their "proven facts" so just what do "they" really know?