How far the space extends in light years?

Question

It is assumed that the diameter of universe is 156 billion light years. Then what may be the diameter of space?

Answer 1

lol, good answer Dave.  I don't recognize the 156 billion ly distance either...but what you seem to be asking is 'how big is the universe?'

No body knows.  That is one of the fundamental questions that scientists are working on now.  That is, the size is probably directly related to the age of the U, and when one is known , the other will be known too.

I can only imagine 3 possibilities:  one, there is only one Universe and it is of finite size, which begs the question "What's beyond the end?"  Two, there is only one Universe and it's infinite, meaning we'll never know, which is kind of depressing, and three, there are many Universes, which begs the question "How many and what's between them?"

Answer 2

The Universe IS space. It does not exist separately. It's like saying, if a sweater is size Medium, how big is the yarn? The Universe does not expand into a pre-existing space, it creates space as it expands. There is nothing 'outside' of it.

Answer 3

From Earth we can see 13.7-billion light years into the universe, but that's definitely not the total size of the universe. There are vast regions that we'll never see because they're receding from us faster than the speed of light.

Answer 4

it aint known becox the universe is always expanding...

Answer 5

Well, I have no idea what your source for the assumed diameter of the universe is, but, as far as I know, space can't exist outside of the universe, so the two must be equal?  Unless you're saying that matter doesn't count as space...  then you would have to subtract the distance of all matter that the "diameter" line you are drawing goes through...  Kind of like measuring how long a slice of swiss cheese is...  do you subtract the holes...  hmmmm, I guess nobody really does that.

Answer 6

Mallard is slightly wrong: The universe is estimated to be 13.7 billion light years old but we can see galaxies that are 47 billion light years away.

How is that possible? Well, during the 13.7 billion years of its existence, the universe has expanded quite rapidly and that's why some galaxies can be seen so far away.

Is that the end of the universe, then? We don't know. All we know is that we can see the light of galaxies that reach us at the speed of light. What is beyond that is beyond what we call the universe's horizon. We don't know about it but we might see it in the future. Likewise, because of its expansion, the universe has also a future horizon, i.e. galaxies we can see now but that we won't in the future because they recess from us so fast that their future light won't ever reach us. But then ... they are travelling faster than the speed of light! Right but again, it is considering the universe expansion and apparently it doesn't contradicts the theory of Relativity.