> It may seem like I'm getting off the subject for a little bit, but trust me, it will lead back to it.
>
> I've always wondered exactly how big is the universe. I mean, our galaxy in just one of possibly millions out there. There is a great chance that there are galaxies out there that we don't know of. But exactly how big is the universe?

It's not of fixed size. It has been expanding ever since the Big Bang, and may continue to do so forever (or, as it turns out, if there is sufficient mass in the universe, it may eventually collapse on itself. We don't yet know for sure, last I heard). The universe seems to be on the order of 10 billion light years in radius right now. This is measured relative to our position...there is no "center" to the universe, really.

> And if the universe is a specific amount of light years big, there must be boundries. Maybe there aren't boundaries and the universe is like a sphere. But saying that maybe there are boundaries, what is past the boundries of the universe? But wouldn't that mean that it's not a true boundry? To me, it's mind boggling. The idea about the size of the universe is beyond my brain's thinking capacity.
>

A boundary of a region implicitly calls for a larger space in which it's "embedded" because the boundary is defined as the set of points which are arbitrarily close to some points in the region and arbitrarily close to some points not in the region. When you talk about the universe as a region, it's all of space, by definition. There are *no* points outside the universe, so by definition there are no boundary points.

I know what you mean by thinking that there *should* be something like a boundary, though. All you'd have to do is take whatever piece of matter is furthest from us, then instantaneously move to that point. There should be nothing further in that direction, so we should be in a sense at some sort of boundary. I have a feeling that general relativity has a way of explaining it -- maybe spacetime is stretched out to make it look like space continues for billions more light years in every direction, once you get to that far point -- but I don't know nearly enough to try to explain it myself.

If you posit a static universe, one that isn't expanding or contracting, it's actually easier to think of a universe without boundaries. It could just wrap around in each direction (like a level of Murkon's Refuge!) Or it could be infinite in all directions. Or, even more interestingly, it could be infinite in one or more directions and wrap around in the other directions (envision an infinite cylinder: you wrap around going left or right, but you go on forever up and down). Now an infinite cylinder *does* have a boundary when we see it as embedded in 3-D space (in fact, the boundary of the cylinder is the entirety of the cylinder), but as I mentioned before it doesn't make sense to talk about the boundary of the cylinder when you view the cylinder as the entirety of space.

> But to get back to where I was actually heading...life. Those two questions at the beginning of this post lead me to think about life and its existance. Now just saying that there is no such thing as other life forms out in the universe besides us on Earth (even if there are people who do believe, I'm just saying theoretically that there isn't), why would the universe run without life forms?

Why wouldn't it?

> Does it possibly run on a different time system that one that exists on earth.

If you mean, "Might the true nature of time be quite different than how we humans perceive it," then I'd think quite possibly.

> Also, what would it be like if there was no "universe"?
>

It would seem that even if there were no physical universe -- no matter, energy, or physical laws, the higher realm of potentiality would remain. There would still be "possible universes" that could be created (by God, if God exists). Even higher than that is the realm of absolute logical truth. No matter what the universe is like, and higher up, no matter what a divine creator might wish, nothing can change absolutes such as the Pythagorean theorem, the infinite size of the set of primes, and even subtler things like Fermat's Last Theorem. Non-mathematical examples could probably be thought up as well, I suppose. We might suppose that the universe could lack the proper framework to make it likely that those truths would ever be discovered, or even, in the lack of a physical universe, that any entity *could* contemplate them, but they'd be truths nonetheless.

I thought about this a few years ago when looking at images of the Mandelbrot set, a fractal specified by one simple equation (Z = Z^2 + C). [Do a Google search for "Mandelbrot" for plenty of info on it.] One might say that such a striking dichotomy of order and disorder, beauty and chaos, unlimited variance and infinitely scaled self-similarity is very good evidence of an intelligent designer to the universe. But no, I think not. The perceived beauty of the images one generates are observer-dependent of course, but the self-similarity and patterns one observes are quite objective. Not only that, but the patterns are not based on any aspect of the physical universe, but based on mathematical computation and truth, which are absolute. It would be *impossible* to have a universe in which these patterns did not exist (though they might well go unnoticed) exactly as they seem to us.