Re: Beyond the observable universe
 

What's beyond the edge of the observable universe? More universe, in my completely uneducated opinion.

It's said that people can't imagine infinity. Humans have a beginning, and an end. Our species had a beginning, and people here are very keen to predict the end. Our entire planet had a beginning and will eventually have an end. We're linear, finite creatures, so it's understandable that we can't comprehend something that isn't finite.

Personally, I think that's bogus. I can't imagine a universe that isn't infinite. It's much easier for me to reconcile an endless universe that has always, and always will be here, than it is for me to imagine the possibilities that would present themselves if the universe did have a boundary, and if it didn't always exist. It's like trying to imagine being dead - you can't do it.

Re: Beyond the observable universe
 

I have the opposite problem. I can't imagine a space without a boundary. It would mean the universe would always have existed, and have no beginning. And if it does have a beginning, and not an end, how did it go from being finite to being infinite? But yeah, it might be that we're simply incapable of imagining something infinite. We can think about it, and consider it as a concept, but when it comes to imagining how it came to, and how it can exist? That's a whole different story. Maybe it is infinite. Or maybe it's a balloon inside an even greater universe.

Re: Beyond the observable universe
 

Define "Universe". My definition is this, the infinite blackness surrounding and including our known surroundings. Your definition appears to be that which is contained within that infinite blackness.

Is that blackness infinitely empty outside of the "known universe", or is there an infinite supply of matter and/or energy? It is difficult for me to imagine infinite matter and/or energy, but it is just as impossible for me to imagine that the there is some magical border to space.

I reconcile these two "impossibilities" by assuming that matter and energy end at some point. This is the finite end of the "knowable universe", but there is no barrier, no end, no wrap-around, it is simply a void. This void will be impossible to measure, it will be impossible to traverse.

In the end, our "knowable universe" is actually a matter/energy bubble that is smaller than a quantum particle in the grandness of the infinite blackness.

Matter can neither be created, nor destroyed, only converted to energy. The infinite blackness does not have a known beginning, neither has it a known end. It is not something that "exists", it is the absence of existence, and that which contains existence.

Our existence has a beginning, our solar system has a beginning, it is theorized that the "knowable" universe had a beginning, and its end will come with it freezes to death. Taking the Bing Bang theory, the Bing Bang does not have a beginning, nor an end, and is still happening.

That is how I understand it.

The greater universe being the non-existent blackness that surrounds the bubble. Like a bubble or balloon, filled with helium, then exposed to lower pressure, the "knowable universe" will expand. Only, not having a physical bubble, or balloon, there is nothing to pop. Having no counter-pressure, it will simply expand at an increasingly slower rate, to an infinite size.

Re: Beyond the observable universe
 

Y'all seem to have formed your picture of the universe from your own thoughts and feelings and supposition, rather than science and mathematics. Why is that?

Re: Beyond the observable universe
 

Believe it or not I've never really given much thought on the project. Occassionally I used to think of what was at the edge and beyond, but then I started waxing into why things exist and deep stuff that usually gets me in a bad mood.

That being said, I was always amused with Futurama's take on the "edge of the universe". I like what I've read in here though, makes me think without getting into an existentialist crisis.

Re: Beyond the observable universe
 

As I recall, the question there is whether the density of the universe is greater than a certain multiple of the square of the Hubble constant. The key point being whether, if I fire a photon off in a given direction, it will eventually come back to me.

But there are no boundaries involved there. To call it a shape is misleading. The Photon, at least under those assumptions, isn't coming back to you because it's run into the surface of the universe and bounced off it or anything – it was always on the 'surface' of the universe.

A sphere is the set of points that are all distance r from a given point. Here r seems undefined. You could stand at the apex of the photon's trajectory and fire another photon off and it would go on a ways before coming back to you – and you could do so an infinite number of times.

...

Maybe it works better with an example:
Say I tell you that space is spherical. Just enter it as an assumption. What can you tell me about what's beyond the observable universe that you couldn't tell me five minutes ago? Say I tell you space is flat - what can you tell me now that's different to what you could tell me if it was a sphere?

If your answer in both cases is the same, regardless of what that answer is - even if it's nothing, then you haven't actually expressed anything meaningful, the terms aren't supported by a framework of concepts that hooks onto reality.

Re: Beyond the observable universe
 

Why did you quote me? Your response didn't address my post at all.

EDIT: To clear things up for you, in the post you quoted I was referring to your preceding post. In it you claimed various things, such as one particular theory of numbers to be fact, and you also seemed set on one particular theory of the structure of the universe. You also claimed we're not well equipped to answer such questions, despite the plethora knowledge we do have, and the numerous valid workable theories.

tl;dr, your post was not structured well (in the sense that your point was a bit ranty) and lead me to believe you didn't know about current theories regarding the things you were talking about.

EDIT2: The answer to the cases is vastly different, actually.

Re: Beyond the observable universe
 

Because I thought that it did.

We're clearly dealing with too great an inferential distance here for the discussion to be worthwhile. Just don't pay it any mind.

Re: Beyond the observable universe
 

Heh, right.

Here's some light (no math knowledge required) reading on the subject, should you wish to be more educated in the matter

Curious About Astronomy: Why is the Universe flat and not spherical?

WMAP- Shape of the Universe

What Do You Mean, The Universe Is Flat?, Part 1 | Degrees of Freedom, Scientific American Blog Network

EDIT: If you're feeling up for it, there are several astronomy journals you can find through Google, though several are of course behind pay walls. :( They can explain current theories much more rigorously.

Re: Beyond the observable universe
 

Go figure, I actually remember reading the original article. It does, however, seem to cover primarily the observable universe, and not what is beyond the horizon. Since we can't see beyond it, we can't really do much other than guess and make estimates based on what little evidence is available. We can assume the rest of the universe, beyond the horizon, is also flat, but it could be curved as well. We probably won't ever know for certain.

... But I'm starting to think this would be better suited for someone with a university degree or something.