the scale of the universe

[Pirian]

Here's a thought: If the universe is finite in size (as suggested by the discussion on it being X light-years across), what's past the "bounds" of the universe? Into what space (ignore bad pun) is the universe expanding?

Well one theory is that the universe creates space as it expands, well in the simplest terms

[Kononeko]

http://img85.imageshack.us/img85/9236/murphy4zd.jpg
"I wonder what the space baby thinks about all of this?"

[Mizango]

Here's a thought: If the universe is finite in size (as suggested by the discussion on it being X light-years across), what's past the "bounds" of the universe? Into what space (ignore bad pun) is the universe expanding?

That's the beauty of science, when we don't know something we simply say 'we don't know'. Do people have lots of theories and interesting ideas? Certainly. But we dont know anything definitively.

But if you want to be mind blown and get all technical then you can look at by definition and get your answer which would be; 'Nothing'. I mean technically speaking nothing exists outside the universe because by the very definition the universe is everything and everything is the universe. You are treading into the world of Theoretical physics and multi-verses, parallel yous and I's etc.. the possibilities are endless if you really want to walk that path.

[Kaylia]

Here's a thought: If the universe is finite in size (as suggested by the discussion on it being X light-years across), what's past the "bounds" of the universe? Into what space (ignore bad pun) is the universe expanding?

Sciences doesnt allow you do say anything about what lies beyond your model. Until we observe interaction with something outside, we will just have to assume the current models are the best and not speculate over what we would do if we had hypothetical data.

That said, it's always a mindfuck to think about the type of structure outside the boundaries of our universe. We might get a better idea once we link quantum mechanics and relativity, but at the moment, it's nothing but pure guess.

That's the beauty of science, when we don't know something we simply say 'we don't know'. Do people have lots of theories and interesting ideas? Certainly. But we dont know anything definitively.

But if you want to be mind blown and get all technical then you can look at by definition and get your answer which would be; 'Nothing'. I mean technically speaking nothing exists outside the universe because by the very definition the universe is everything and everything is the universe. You are treading into the world of Theoretical physics and multi-verses, parallel yous and I's etc.. the possibilities are endless if you really want to walk that path.

Well, at this point it's just semantic. Usually, the universe is everything that exist within this "space and time", and it corresponds to the universe as we know it. If there is something outside these boundaries, it would still "exist", but it would most likely be outside space and time (as we know it).


If universe for you literally mean everything, then nothing is the only possible answer.

[Mizango]

Yep. 'Nothing' seems to be the answer most people would give and accept. This reminds me of the conversation Woozie and I had a few months ago about this very topic, about what it would be like if the universe were just a bubble in a endless expanse of bubbles.

I swear we were not high.

[Sylvrdragon]

Yep. 'Nothing' seems to be the answer most people would give and accept. This reminds me of the conversation Woozie and I had a few months ago about this very topic, about what it would be like if the universe were just a bubble in a endless expanse of bubbles.

I swear we were not high.

This is basically what I believe. I think our "Universe" is just one expanding ink blot among countless others. I think that by the time we come into contact with another blot, entropy will have reduced this 'verse to subatomic particles or we will have been sucked into what's left of the massive black holes.

Actually, that's how I picture things to have begun: That the whole of our universe is a tiny tiny fraction of a preceding universe that was sucked into the nearest singularity, which later exploded in what we think of as the Big Bang. It might even explain why the singularity at the start of our universe exploded- if a stray particle from another universe collided with it at high speeds.

-or, this might just be a sci-fi junkies ignorant pet theory that would be met with a sigh of exasperation and barely suppressed rage from a real Physicist.

[Kaylia]

I don't know with term like "multiverse" tossed around, I think we would find a new word to describe the new structure that include the big bang. But like I said, it's just semantic, and doesnt really matter.


If there is something else, "bubble" is a safe guess with all the central force going on in physics. It doesnt bother me as much as a "cube" or something. Actually, I have hard time imagining something that isnt grouped like atoms/planet or w/e.

[Diamicles]

treading into the world of Theoretical physics and multi-verses, parallel yous and I's etc.. the possibilities are endless if you really want to walk that path.

these sorts of things give me a warm fuzzy feeling inside, I loved my theoretical physics course (especially since I was the only student in there that semester)

[Mizango]

these sorts of things give me a warm fuzzy feeling inside, I loved my theoretical physics course (especially since I was the only student in there that semester)

QQ I've had something like that happen to me before as well, but there were 3 of us lol.

[Zeh]

You guys ever think that we were never supposed to think about this, or if we were more advanced we'd be able to come up with an answer? It's damn fool luck that we evolved into beings able to colonize the entire planet, let alone think about the mystery box of the universe. I can't comprehend this shit. No one can. If I had some uber starship traveling at the edge of the universe just to see what the universe was expanding into I'd probably die. How the fuck is the universe expanding? What is it creating 'blank' space from? I thought all atoms and matter came from matter like what the fuck

[Mizango]

How is it expanding? Draw dots on a balloon and blow it up, that will give you a really good visual. Just know that we know and can see that galaxies and so on are moving away from one another and from us. Read up on Edwin Hubble (Yes, the telescope is named after him) and Doppler effect and it will give you full details.

On the way home from work now, so for now you get a rush job lol. I will come back to this when I get there!

[xopher]

You guys ever think that we were never supposed to think about this, or if we were more advanced we'd be able to come up with an answer? It's damn fool luck that we evolved into beings able to colonize the entire planet, let alone think about the mystery box of the universe. I can't comprehend this shit. No one can. If I had some uber starship traveling at the edge of the universe just to see what the universe was expanding into I'd probably die. How the fuck is the universe expanding? What is it creating 'blank' space from? I thought all atoms and matter came from matter like what the fuck

Never meant to think about this?

What do you think meant for us to not think about this?

Being shown the universe on this scale makes me believe that nothing out there even knows of our existence.

[Pirian]

How the fuck is the universe expanding? What is it creating 'blank' space from? I thought all atoms and matter came from matter like what the fuck

It's not making new matter, just new "space-time". It's called the "vacuum" of space for a reason there's nothing there

[Zeh]

By not meant to, I mean like every other creature on the planet besides humans. They don't and can't think about this. I think of life as an anomaly. Something that just happened, much akin to my birth

@Mizango

Balloons pop at some point, don't they?

[Woozie]

The thing I hate about the balloon analogy is that it depends on the fact that there's something for the balloon to expand into (the balloon analogy is a two dimensional surface of an object in a three dimensional world that it is expanding in, whereas the universe isn't really expanding into anything). The whole point in the analogy is to show that space isn't expanding "into" anything, but the analogy gives virtually the opposite impression.

Nonetheless, it's the best analogy we've got. The simple fact is, our brains aren't capable of comprehending what's truly going on, which is why we're lucky we can explain everything with math instead (math doesn't care what our brains can and can't comprehend.

Edit: Also

http://www.mso.anu.edu.au/~charley/p...DavisSciAm.pdf

http://www.astro.ucla.edu/~wright/cosmology_faq.html

Should answer a lot of questions people tend to ask in these threads.

[Correction]

Reminds me of a Simpsons intro.



Edit http://www.youtube.com/watch?v=7GDC3u8k02c

The original

[Kaylia]

It's not making new matter, just new "space-time". It's called the "vacuum" of space for a reason there's nothing there

What's about virtual particles?

[Kaylia]

The thing I hate about the balloon analogy is that it depends on the fact that there's something for the balloon to expand into (the balloon analogy is a two dimensional surface of an object in a three dimensional world that it is expanding in, whereas the universe isn't really expanding into anything). The whole point in the analogy is to show that space isn't expanding "into" anything, but the analogy gives virtually the opposite impression.

Nonetheless, it's the best analogy we've got. The simple fact is, our brains aren't capable of comprehending what's truly going on, which is why we're lucky we can explain everything with math instead (math doesn't care what our brains can and can't comprehend.

Edit: Also

http://www.mso.anu.edu.au/~charley/p...DavisSciAm.pdf

http://www.astro.ucla.edu/~wright/cosmology_faq.html

Should answer a lot of questions people tend to ask in these threads.

Raisin bread analogy is slightly better, since you can bring your attention to the raisin within the bread, and not so much the expansion of the shape. But I agree, its hard to find example to describe space/time physics.

[Woozie]

What is the raisin bread analogy? I've never heard it explained that way (or any other way other than the balloon. Seriously, I say this a lot, but physicist are way too uncreative lol).

[Woozie]

A bit late, but the "observed universe" part isn't accurate, since it didn't take in consideration the universe expansion. It should be bigger than 13 billions light years. No?


Pretty cool visual though.

Well, the furthest objects we can see are now 47 billion light years away. So the size of the observable universe depends on how you define the observable universe.