Edge of our Universe

[chaperon2005]

Does our Universe have boundries and if are there any theories about what is outside those boundries

[jake-the-peg]

Whether the Universe is bounded or not is one of the great questions.

A lot depends on how much matter there is in it.

I think most of the smart money at the moment is on an unbounded Universe but it's far from certain.

One of the most interesting ideas is a finite unbounded Universe.

In the same way that if you travelled far enough in one direction on the surface of a sphere you would get back to the same place such a Universe would be the same but in 3D.

This would involve a Universe that is shaped like a 4 Dimensional Torus (ring doughut).

It's pretty hard to visualise but here's one represented in 2D
https://www.youtube.com/watch?v=nH9dFr3tGH4

[nix-j-c]

look on my question that i posted a few hours before you.
its only a few questions below this.

[Scarramouch]

The doughnut theory is gaining more and more credibility. But I think what Einstien once said is interesting more as an observation on our nature than on cosmology. "only two things are infinite. The universe and human stupidity,and i'm not sure about the former".

[fredsie]

I think the questioner is really asking "if the universe has boundaries, what is outside them?" The generally accepted answer to this is "nothing". The notion of a universe with a boundary is another way of saying "this is all the space there is for us to exist in - there isn't anything else, or anywhere else".

It then makes no sense to talk about what's outside - if there was anything outside (even just empty space), then that would be part of the universe as well and so not really "outside". If you see what I mean! :-)

[Scarramouch]

quite correct. But if einstien was right and the universe is infinite then the question of an "outside" is moot anyway. I know this is a mind boggling concept. Several physicists and mathematicians have been driven made pondering infinity. A couple even committed suicide while trying to quantify it.

[bobthebandit]

The Universe has no boundaries and is continually expanding. This is in order to sustain life on Earth. If the Universe did have boundaries, than the Universe would act like a giant microwave oven, causing all the harmful radiation etc to bounce back us and ultimately destroy us.
The expanding universe is designed for our own safety,and acts as a giant 'dustbin" for all the harmful radiation, gamma rays etc which are out there.