(August 27, 2016 at 4:26 pm)Alex K Wrote: It doesn't have to be space-infinite to be flat. Standard cosmology works exactly the same if it is a spatially flat but finite manifold, e.g. a 3-torus, as long as all the radii are a bit larger than the observable universe, so I doubt somewhat that there are serious papers empirically arguing for actual infinteness. There are however papers looking for effects of *finiteness* in the cosmic microwave background, but so far no evidence has turned up, with means no more than that the universe is probably at least a bit larger than the observable universe - a conclusion that doesn't surprise anyone, really.
Good day to you Alex! What is a 3-torus and does it predict the same negative/saddle like curvature of space as a "normal" 3d torus?
![[Image: Torus.png]](https://images.weserv.nl/?url=www.math.cornell.edu%2F~mec%2F2008-2009%2FHoHonLeung%2FTorus.png)
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Consider me a satellite forever orbiting,
I knew the rules but the rules did not know me, guaranteed." - Eddie Vedder
