Question: Whats beyond the universe?

Matthew Malek answered on 18 Mar 2014:

This is a really tricky question, and has a lot in common with another question I often hear, which is “What was before the universe?”

To ask “What is beyond the universe?” is like asking what is in the space outside of space. To ask “What was before the universe?” (or before the Big Bang) is like asking what was in the time before time.

Space and time — merged together by Einstein into “spacetime” — is the very fabric of the universe. So space and time are properties of the universe, and I don’t think our brains can really conceive of the “space outside of space” or the “time before there was time” any more than my cat’s brain can conceive of algebra. He’s a very clever little tabby cat (and full of personality!) but his brain just can’t do it!

Indeed, when it comes to the questions of “space outside space” or “time before time”, there may not even be an answer!

Now, after saying all that, I should come back to your original question and note that there is a subtle difference between “the universe” and “the observable universe”. Whilst the universe encompasses all of space, we cannot actually see all of it, because we are limited to viewing light that has had time to reach us since the Big Bang occurred. That’s a very large amount of space… but it isn’t everything. And we don’t even know how much larger the universe is compared to the part that we can see! It may well be infinite.

In fact, it may be that other regions of the universe that we cannot see have very different physical laws — there has been speculation that different bubbles, or regions of space around the time of “inflation” (a period of rapid expansion shortly after the Big Bang) developed with different physics. For instance, why is the speed of light what it is? No good reason that we can tell… and it may be different in a part of the universe that we cannot observe!

But this is all speculation. Until and unless we can ever observe such places (maybe with help from a wormhole, if they exist??), all we can really do is guess about them!