The last podcast that I listen to dealt with the shape of space and that the universe is flat. I was wondering if the universe could actually be a sphere with a size so large that to use it appear flat much like the earth does with a view of the horizon. Our galaxy is just part of the crust o the sphere universe which would be thin compared to the dimensions of the sphere itself. The rapid expansion of space could have made it so the the distances to other reaches of the universe are so distant that not light or any other ray could be detected? Just wondering if anyone has thrown this out there and if it has be shown wrong yet by math/physics?