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

This is a common question. You need a mental leap here – light cannot travel faster than the ultimate limit, in a vacuum. BUT, space itself is expanding during these 13.8 billion years.

Objects aren’t just moving *through* space – the fabric of space (which is part of the same bang as the matter) has been stretching at the same time.