The discussion centers on the concept of an expanding universe, specifically addressing the question of how an infinite universe can expand. Cosmologists define "expansion" as the increasing distances between widely separated galaxies, with an average rate of about 1/140 of one percent every million years. This expansion is perceived from within the universe, not from an external viewpoint, clarifying that an infinite universe can exhibit a pattern of distance growth similar to a finite one.
PREREQUISITESAstronomers, cosmologists, physics students, and anyone interested in understanding the dynamics of the universe's expansion and its implications for infinity.
LSulayman said:...
How can the universe expand while it's infinite?
LSulayman said:...
How can the universe expand while it's infinite?
marcus said:You have to understand what the cosmologists who say "expand" mean by that word.
They mean that distances between widely separated galaxies are increasing.
On average the rate of increase is currently about 1/140 of one percent every million years.
They do not mean that you could stand outside the universe and see it get bigger!
They are talking about a pattern of distance-growth seen from inside.
An infinite thing can have that pattern of distance-growth, just as easily as a finite thing.
It is expansion seen from the inside. So the thing does not have to be finite.