Where does the universe expand into?

[leafman91]

According to the Big Bang theory at current, it all starts off with a singularity, surrounded by not even nothing. All there is and isn't is the singularity. There is no 'where', and no 'nowhere'. It is physically impossible for either of them to exist. Then the universe expanded one day. Why? Where to? What is meant by saying the singularity expands, when it is already explained that there is no 'where' for the singularity to expand to? How do you fit all of everything in the universe into a point that's infinitely small? Where is the universe expanding into now?
They say it isn't the atoms that grow larger, it is the actual space the atoms occupy that grow larger. How does nothing expand?Where does nothing expand to?

[Starthinker]

It expands into a size 44.

[Undesired Walrus]

I'm sure you will get many intelligent, exciting, and incomprehensible answers, but 'I don't know' is the most exciting answer, to me.

[Cathoskeptic]

You can find the answer at the Alamo. In the basement.

[Ziggurat]

A similar question was asked very recently by someone else. My response (http://forums.randi.org/showthread.php?p=5252498#post5252498) to that post might be useful here too.

[Aitch]

It expands into a size 44.

Cup size? ;)

[Perpetual Student]

A similar question was asked very recently by someone else. My response (http://forums.randi.org/showthread.php?p=5252498#post5252498) to that post might be useful here too.

That's a fascinating question and an interesting response. Ultimately, all we really have are mathematical models of reality, but the question seems to have a haunting need (for me) to be addressed in a manner that does not seem possible -- like "what is the ultimate reality of an electron?"

[sol invictus]

A similar question was asked very recently by someone else. My response (http://forums.randi.org/showthread.php?p=5252498#post5252498) to that post might be useful here too.

Regarding your post, it's worth pointing out that one of the standard possibilities for cosmology is an open universe. Such a space cannot be embedded in a space of one higher dimension (you need more, I think at least two, but maybe more). So adding extra dimensions can make the extrinsic geometry far more complicated and hard to visualize than the intrinsic geometry.

To respond to the OP, first off it's better not to "start" with the singularity. Start (in your mind) with the universe at a later time, say today, and then run it forwards and backwards in time and see what happens to it. Now, what is it expanding into? Well, mathematically the answer is as Zig says - it's not necessary for there to be anything outside for it to expand into. It can be the whole space and still expand.

Here's an example you may be able to picture - an infinite 2D plane covered with dots. The dots are uniformly distributed in a square lattice, one inch apart. As time passes, the separation between every given pair of points increases as if the plane is stretching out in all directions, but doing so everywhere across its entire infinite surface. So there you go - that's an expanding 2D space with no need for anything more than 2D (i.e. nothing for it to expand into).