If the Universe is about 13.7 billion years old, and the diameter of the observable universe is 93 billion light years, how can it be that wide if the universe isn’t even old enough to let light travel that far that quickly?

Question

If the Universe is about 13.7 billion years old, and the diameter of the observable universe is 93 billion light years, how can it be that wide if the universe isn’t even old enough to let light travel that far that quickly?

In: 5624

Answer 1

The fabric of space-time can expand much faster than the speed of light. During the early universe (before stars and galaxies) there was an expansion period where the space-time of the universe expanded exponentially faster than the speed of light (by orders of magnitude).

This pushed all the “materials” that would later condense to form stars and galaxies farther away then light would be able to travel to go to the other areas.

The observable universe is 93 billion light years, but that’s only what we can “see” there is much much more universe we can never “see” because of the early expansion period during the birth of our universe pushed it outside that boundary.