Add everything together, and we still have less than half the mass density needed to make a flat universe.

The paths turned out to be straight, providing the main piece of evidence for the flat universe.

All the data are consistent with a flat universe, said scientists on the projects and others who have read the teams' reports.

They pointed out that living in a flat universe was like sitting atop a very steep mountain.

The models we invented in the 1980's to try to bring a flat universe into accord with the observations at the time are clearly wrong.

Imagine the universe as a thin rubber sheet, very flat.

The case for dark energy got even stronger a year later, when the cosmic background observations reported evidence of a flat universe.

"Ah, no, people like the idea of a flat universe because they find negatively curved space difficult to deal with."

Thus, physicists suggest a flat universe could come from nothing.

These points are only defined in an asymptotically flat universe.