what happens when you reach the end of the universe?

[[censored]]

someone posted a few days ago that the universe is estimated to be something like 40 billion light years in size, basically really big but still finite.

Should I think of being i the universe like being in large box where I could come to a point where travel in that direction is no longer possible?

Or should I look at like say the internet? where it is technically finite but without a stopping point to a starting point.

what are the latest theories on this?

[slickpoppa]

The answer is we don't know. link (http://en.wikipedia.org/wiki/Universe)

[Girchuck]

If the Universe is expanding with the speed of light, then you will not be able to reach the end until it stopped expanding, and we don't know whether or not it is going to stop expanding.

[kitaristi0]

I believe it's commonly accepted that the universe is constantly expanding, and thus it would be impossible to reach "the end of the universe".

[kitaristi0]

According to Hubble's experimental observations, the further away a galaxy is from ours, the faster it is moving away from us. (This is determined by utilising the Doppler effect). This would indicate that the universe is expanding and like I said in my previous post, it would thus be impossible to reach the end of the universe.

[kpux]

[ QUOTE ]
Or should I look at like say the internet? where it is technically finite but without a stopping point to a starting point.

[/ QUOTE ]

I think this is more what cosmologists are leaning to nowadays. The universe is probably finite, but unbounded. Imagine that we are inside a giant dodecahedron, except when you reach one of outside faces, you simply come back "into" the universe through another one of the faces. So, all of the faces of our dodecahedron are identified in pairs, creating a four-dimensional object.

[ZeeJustin]

[ QUOTE ]
Both popular and professional research articles in cosmology often use the term "Universe" when they really mean "observable universe". This is because unobservable physical phenomena are scientifically irrelevant; that is, they cannot affect any events that we can perceive, and therefore, it is argued, effectively do not exist

[/ QUOTE ]

The way I look at it is, the lack of matter aka "space" is part of the universe. The lack of matter has to be infinite, therefore, the universe is infinite in size.

However, given closed universe theories, it is possible that within this infinite universe you could draw an imagineary box, and this box is just big enough so that it is physically impossible for matter to ever escape it. This implies that the big bang is a reocurring phenomenon, and that the universe will keep expanding and contracting. The imagineary box I described, is simply the "Observable universe" in the above quote.

[Zygote]

[ QUOTE ]
According to Hubble's experimental observations, the further away a galaxy is from ours, the faster it is moving away from us. (This is determined by utilising the Doppler effect). This would indicate that the universe is expanding and like I said in my previous post, it would thus be impossible to reach the end of the universe.

[/ QUOTE ]

This is correct. According to general relativity, nothing can travel faster than the speed of light. Also, general relatively predicted that our world is not static. At first, Eistein didn't realize this and presumed the world was static using his flawed cosmological constant which he later deemed to be his biggest mistake. Therefore, the universe is either contracting or expanding. As a result of Hubble's observations, we can now conclude that the universe is expanding.

[BluffTHIS!]

The real question here is, into what is the universe expanding? The vacuum of space as we know it does contain relatively minute samples of matter and energy, but that cannot exist already in the *what* that the universe is expanding into since the universe by conventional definition contains all such matter and energy.

[Malachii]

You stop and have a burger at the Restauraunt at the End of the Universe!

[kpux]

[ QUOTE ]
The real question here is, into what is the universe expanding? The vacuum of space as we know it does contain relatively minute samples of matter and energy, but that cannot exist already in the *what* that the universe is expanding into since the universe by conventional definition contains all such matter and energy.

[/ QUOTE ]

I was going to say that this question doesn't make any sense because our three spatial dimensions are limited to what we call the universe. So the universe is all of space, and isn't expanding "into" anything.

But perhaps our three-dimensional universe is the surface of some four-dimensional manifold, like the two-dimensional surface of a sphere is the "outside" of a three-dimensional ball.

Also, if anyone has read "The Elegant Universe" by Brian Greene, he goes into a bit of detail about something he refers to as a multiverse, which he describes vaguely as a sort of multi-dimensional sea of universes, all expanding and contracting. I wish I could remember his exact wording better.

[Zeno]

[ QUOTE ]
what happens when you reach the end of the universe?

[/ QUOTE ]


There is a toll both occupied by God. If you can pay the toll you can continue, if you can't pay the toll you must turn around and head back the way you came. The real question then becomes: What's the toll?

I'll be back later with the answer - Meanwhile, go ahead and make some guesses.

-Zeno

[BluffTHIS!]

Even though your post is a clear hijack by a master hijacker, the answer is that there is already someone who paid the toll, Jesus Christ, and He is willing to give you the voucher for same if you are willing to accept it.

[Ezcheeze]

[ QUOTE ]
The way I look at it is, the lack of matter aka "space" is part of the universe. The lack of matter has to be infinite, therefore, the universe is infinite in size.

However, given closed universe theories, it is possible that within this infinite universe you could draw an imagineary box, and this box is just big enough so that it is physically impossible for matter to ever escape it. This implies that the big bang is a reocurring phenomenon, and that the universe will keep expanding and contracting. The imagineary box I described, is simply the "Observable universe" in the above quote.

[/ QUOTE ]

I think "lack of matter" is a bad way to describe space. What reason is there to think "lack of matter" has to be infinite?

As for the big bang, the current view on the univers is that it is not only expanding but expanding at an accelerating rate which gives no impression of reversing. Also, scientists have observed that the universe is flat on a global scale. This implies it will just keep expanding, there isn't enough matter in the universe to cause it to collapse back.

[Prevaricator]

Here's a better question: If the Universe contracts, what will happen when the edge of the universe reaches you?

[BluffTHIS!]

You will have already been dead for billions of years before our sun went nova when and if that occurs.

[David Sklansky]

My father told me when I was a kid that it was like Flatland inhabitants living on a sphere. You come back to where you started from. Don't know if that is the commonly accepted theory nowadays.

[Zygote]

[ QUOTE ]
My father told me when I was a kid that it was like Flatland inhabitants living on a sphere. You come back to where you started from. Don't know if that is the commonly accepted theory nowadays.

[/ QUOTE ]

I asked a friend of mine who is currently completing a dual engineering and physics degree this same question and his explanation is identical to the one you recieved from your father.

[12AX7]

[ QUOTE ]
[ QUOTE ]
My father told me when I was a kid that it was like Flatland inhabitants living on a sphere. You come back to where you started from. Don't know if that is the commonly accepted theory nowadays.

[/ QUOTE ]

I asked a friend of mine who is currently completing a dual engineering and physics degree this same question and his explanation is identical to the one you recieved from your father.

[/ QUOTE ]

Err... ummm... you fall of the edge and fall into a pit of monsters?

Seriously though... that still leaves the question...

So if you come back to the beginning... what is this universe contained within?

And then what about that? And that? ....

LOL!

Intersting questions but really... wouldn't solving problems like war, poverty, full employment, etc. be more immediately useful?

I mean, until the bottom levels of Maslow's Hierarchy are filling in for everyone... what difference does it really make?

[drudman]

[ QUOTE ]
You will have already been dead for billions of years before our sun went nova when and if that occurs.

[/ QUOTE ]

You're no fun at all.

[[censored]]

[ QUOTE ]

Intersting questions but really... wouldn't solving problems like war, poverty, full employment, etc. be more immediately useful?



[/ QUOTE ]

I solved all those problems earlier this week in the politics forum. I've since moved onto bigger things

[Zeno]

[ QUOTE ]
You will have already been dead for billions of years before our sun went nova when and if that occurs.

[/ QUOTE ]

First get your facts straight, the Sun will become a Red Giant in about 6 billion years. It will not 'go nova'. Here is a link for an explanation, read it and then click on red giant withing the article (a nova happens in a binary star system). Nova/ Red Giant (http://en.wikipedia.org/wiki/Nova)

And for more interesting suff on the universe check out Dark Matter What's this stuff? and why it's so important (http://astron.berkeley.edu/~mwhite/darkmatter/dm.html) and Dark Energy Acceleration into the void (http://www.lbl.gov/Science-Articles/Archive/dark-energy.html) .

Interesting and fasinating I would say and all so relevant to the OP.

-Zeno

[TStoneMBD]

if space is expanding at the speed of light, and nothing travels faster than the speed of light, then there is no inside edge of the universe, only an outside edge if there is space outside of the universe. nothing will ever reach the inside edge because it does not exist according to time.

someone here mentioned that space is expanding at an accelerating rate. well how can this be if nothing travels faster than the speed of light?

it seems apparent to me that if the universe is expanding at the speed of light, and that expansion comes from equal sectors of all parts of the universe, then it would appear to us that the universe is actually decelerating because as the universe becomes more vast, each sector expands at a slower rate. a simliar comparison would be 1/2, 1/3, 1/4, 1/5, etc.

an idea that intrigues me from this thread however, is what does happen if the universe is bound to contract? will the universe contract so tightly that eventually all the matter is touching each other in compact form? will the pressure of the contracting universe make the matter explode? where will the particles go? do they just evaporate? it is possible that all universe matter cannot be destroyed and when the edge of the universe reaches the pressure of the matter by gforce that this will cause another universe expansion?

[12AX7]

[ QUOTE ]
[ QUOTE ]

Intersting questions but really... wouldn't solving problems like war, poverty, full employment, etc. be more immediately useful?



[/ QUOTE ]

I solved all those problems earlier this week in the politics forum. I've since moved onto bigger things

[/ QUOTE ]

OK... so about that second level of Maslow's hierarchy... can you get me a date with the gal in your avatar? LOL! /images/graemlins/smile.gif

[12AX7]

Well, bein' an oldster I haven't thought about these things in years. But I believe the physics types and astophyics types posit that after the expansion phase is over a contraction will occur until the mass is so compressed another big bang will happen. But I could be remembering things a bit fuzzy.

Sounds like a circle to me.

[kitaristi0]

[ QUOTE ]
an idea that intrigues me from this thread however, is what does happen if the universe is bound to contract? will the universe contract so tightly that eventually all the matter is touching each other in compact form? will the pressure of the contracting universe make the matter explode? where will the particles go? do they just evaporate? it is possible that all universe matter cannot be destroyed and when the edge of the universe reaches the pressure of the matter by gforce that this will cause another universe expansion?

[/ QUOTE ]

Our universe isn't necessarily bound to contract. There are 3 generally accepted possible fates of our universe, and only one of them involves the universe contracting. If in fact our universe is a 'closed' universe, eventually the expansion of our universe will stop. Due to gravity, the universe will then collapse into a single point.

If, however, our universe is a 'flat' universe, the force of gravity keeps on slowing down the expansion, but it takes infinite time to get to rest. Thus the universe would just be, without expanding or contracting.

If our universe is an 'open' universe it'll continue to expand forever.

[Zeno]

[ QUOTE ]
If, however, our universe is a 'flat' universe, the force of gravity keeps on slowing down the expansion, but it takes infinite time to get to rest. Thus the universe would just be, without expanding or contracting.

If our universe is an 'open' universe it'll continue to expand forever.

[/ QUOTE ]

This is discussed some in the links I provide in my response to BluffTHIS. One reason I posted them.


-Zeno

[Prevaricator]

[ QUOTE ]
You will have already been dead for billions of years before our sun went nova when and if that occurs.

[/ QUOTE ]

No [censored]? Jesus christ. WHat happens to the star when the universe contracts then. Is that even possible?

[TStoneMBD]

im a little confused on why the universe expands in a constant and why it expands at the speed of light. does the universe expand at the speed in which light tries to reach new territory or it solely from the continual motion of the big bang?

[mostsmooth]

im not sure if this is a totally stupid question, but is the common belief that there was once a infinitely large space that has now become partially filled (with our "universe")due to the explosion of a singularity, or that there was once a singularity that exploded and the outer bounds of that explosion and expansion are the bounds of our "universe". in one case, whats on the other side of edge of the universe would be empty space, the other case would be that whatever enveloped the singularity before the explosion, envelopes it now.

[Cyrus]

[ QUOTE ]
The Sun will become a Red Giant in about 6 billion years.

[/ QUOTE ]

Carl Sagan was approached after a lecture by a member of the audience and was asked about that time frame again.
"Billions", said Sagan.
"Oh", the man was clearly relieved. "I heard milions"...

[Cyrus]

Concepts of time and space as we know them in our earthly macroscopic world should be breaking down quite a lot when we go cosmic. I would not expect us to hit some kind of wall like Truman did when he tried to escape his Show. I'd rather expect a never ending expanse - but, then again, "never" is probably yet another inappropriate term in this context.

[K C]

If space is expanding, what existed in this new space prior to it being "created"? From a three dimensional perspective this concept becomes absurd. Thus there seems more to this, probably a lot more, than we can conceptualize. Perhaps the universe isn't the "concrete" thing we perceive it is, but is instead an idea, although this would involve considerable expansion of our concept of "ideas." Perhaps everything exists as such ideas as a matter of fact. We are not speaking merely of our ideas but rather an unimaginable complexity of individual ideas in ralationship with one another. This may all seem silly but it no less silly than some of the notions that empiricists hold.

KC

[quinn]

[ QUOTE ]
the universe is estimated to be something like 40 billion light years in size, basically really big but still finite.


[/ QUOTE ]

Nonsense. A light year is a distance, the universe is 3-dimensional (or 4 maybe? but that one doesn't apply here). You can't describe the size of the universe with a length.

[kpux]

he probably meant in diameter

[loose passive]

On the outside of the universe is pure energy that is being coverted into matter as the big bang continues.

[Cyrus]

[ QUOTE ]
If space is expanding, what existed in this new space prior to it being "created"?

[/ QUOTE ]


I already claimed that our perception of this world (and the accompanying physics) are quite adequate in describing it -- and getting better at it every day, although not at the pace of the recent centuries.

But this perception breaks down as soon as we get away from the physical world we can immediately understand/experience, and enter the micro world of electrons (which are not the neat, little round spheres of our school lab) or the macro world of the cosmos. (How do we visualize a black hole?)

Ergo, the notions of "before" and "after" are highly suspect already.

Allow me to quote, with the required humility, the man himself. When his close friend of fifty years Michele Besso died in March 1955, Albert Einstein wrote a letter of condolence to Besso's sister and son in Switzerland. The letter ended thus:

[ QUOTE ]
... Now he has departed from this strange world ahead of me. That means nothing. People like us, who believe in physics, know that the distinction between past, present and future is only a stubbornly persistent illusion.

[/ QUOTE ]

Einstein went serenely to his death four weeks later.

[carlo]

A light beam does not go out into "infinity" but reaches the end of its journey and returns in a metamorphosed state. There is something to be said about return from the "other side"-projective geometry will help here. The snake biteing his tail is a symbol which is apropos to this question. All is not always what it seems.

regards,
carlo

[tek]

[ QUOTE ]
My father told me when I was a kid that it was like Flatland inhabitants living on a sphere. You come back to where you started from. Don't know if that is the commonly accepted theory nowadays.

[/ QUOTE ]

But it's not like living on a sphere. It's more like living in a spere. The sphere is the universe. If one were able to reach an outer boundary, there are tangents within the sphere's inner boundaries that could be taken. One would not necessarily have to travel along circumpherence of the inner curved boundary.

[[censored]]

[ QUOTE ]
[ QUOTE ]
My father told me when I was a kid that it was like Flatland inhabitants living on a sphere. You come back to where you started from. Don't know if that is the commonly accepted theory nowadays.

[/ QUOTE ]

But it's not like living on a sphere. It's more like living in a spere. The sphere is the universe. If one were able to reach an outer boundary, there are tangents within the sphere's inner boundaries that could be taken. One would not necessarily have to travel along circumpherence of the inner curved boundary.

[/ QUOTE ]


Dude you just blew my mind!

[nothumb]

This shit freaks me the fuck out.

NT