I have read about how space-time is shaped by gravity - fine. Is there an underlying assumption that 3D space exists in the first place? (because thats where we live). If I were to place a 3D sphere of radius 1 billion miles into nothingness - would it hold up? I mean there is nothing to define its boundary or its relative length measurement - its empty space (no time added!) - it appears to be an illogicality as I cannot understand how it could exist at all. It would not rush out at the speed of light surely - why would it? (I am trying to show that 3D space is made in information - an easy task - and impossible in "real physical space" i.e. there isn't any) Really grateful for knowledegable reply especially if there is an undelying assupmption about its existence in the first place.