flat universe

Cultural  

1. If there is just enough matter in the universe for its gravitational force to bring the expansion associated with the big bang to a stop in an infinitely long time, the universe is said to be flat. The flat universe is the dividing line between an open universe and a closed universe.

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Most theorists believe that the universe is flat.

Example Sentences

With the publication of a new astrophysics study, there are now camps of "flat universe-ers" and "circle universe-ers" within the realm of physics; though notably, in this context, a "flat" universe isn't quite analogous to a flat Earth.

From Salon

“The assumption of a flat Universe could therefore mask a cosmological crisis where disparate observed properties of the Universe appear to be mutually inconsistent.”

From Salon

In a flat universe, one might leave Earth at a high speed and never return to where one started; but in a closed, curved universe, a particle leaving Earth and moving in a straight line would, eventually, return to where it started.

From Salon

And the physics of that superfast expansion point to a flat universe.

From Scientific American

So it’s been largely rejected in favor of a “flat universe” that extends without boundary in every direction and doesn’t loop around on itself.

From Scientific American