Does inflation predict a closed universe? I read somewhere that both a closed and a finite flat universe would have zero total energy in General Relativity (On the Zero-Energy Universe). But the best evidence shows that the universe is flat and infinite: "We now know (as of 2013) that the universe is flat with only a 0.4% margin of error. This suggests that the Universe is infinite in extent" (NASA).
In this video, at 1:09:59, Lawrence Krauss says: "[Inflation] tells us, remember, that in the largest scales the universe isn't flat. It's actually closed." But the whole point of his argument is that the universe is flat and, because of that, its total energy is exactly zero (e.g., from 53:32 to 54:23).
So, I'm confused. Does inflation really predict a closed universe? If so, how is that compatible with the evidence that the universe is flat?
 A: In this link, the contradiction is "explained":

The tremendous expansion greatly dilutes any initial curvature. Think, for example, of standing on a basketball. It would be obvious that you are standing on a (2-dimensional) curved surface. Now imagine expanding the basketball to the size of the Earth. As you stand on it now, it will appear to be flat (even though it is actually curved if you could see it from large enough distance). The same idea extended to 4-dimensional spacetime accounts for the present flatness (lack of curvature) in the spacetime of the Universe out to the greatest distances that we can see, just as the Earth looks approximately flat out to our horizon. In fact, the inflationary theory predicts unequivocally that the Universe should globally be exactly flat, and therefore that the average density of the Universe should be exactly equal to the closure density. It is this prediction that we alluded to earlier when we said that there were theoretical reasons to believe that the density of the Universe was exactly equal to the critical closure density. 

It hand waves that flatness is a very good approximation in the inflationary model, curvature unmeasurable in the observable universe. The curving is sent outside of it.
