What condition is necessary for the universe to be closed?
A) The universe must have no mass in it.
B) The density of the universe must be large.
C) The density of the universe must be small.
D) The cosmological constant must be large.

Question

Quizplus · Accepted Answer

For the universe to be closed, its density must be large enough to eventually halt expansion and cause it to collapse back on itself, according to the Friedmann equations which describe the universe's expansion.

What Condition Is Necessary for the Universe to Be Closed