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Spaceship on "edge" of universe

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mcarans

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If a space ship was able to travel faster than our universe is expanding and thus reach the edge, what would happen to the ship?
 
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SJQ

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It would fall off? :lol: (sorry, couldn't resist)

My (limited) understanding is that there isn't an edge to reach. If you were to reach the edge of the visible universe (the universe as seen from Earth) and then looked outward away from Earth in the direction of your travel, you would see more of the universe, a view that looks to be pretty much more of the same sort of thing you saw from Earth. You would just be the first human to have ever seen that "pretty much more of the same sort of thing" additional piece of the universe.

Your (new) visible universe wouldn't be the same visible universe as seen from Earth (still the same universe, though). If you looked back towards Earth you'd still be seeing a view up to 13+ billion years old (at the edges of your visible universe). You couldn't see Earth, however. Your new position is 13+ billion light years from Earth. Earth is only around 4.5 billion years old, so the light of the Earth's formation won't arrive at your location for billions of years yet. The perspective changes with both location and time.

In your newly visible, not yet seen by Earth part of the universe, the same physical laws would apply, and planets, stars, galaxies, and clusters would form in the same way as they did in Earth's visible universe. It's the same universe, Earth just isn't old enough to see it yet. For this reason, navigation over cosmological distances would be interesting. Any star map you made while on Earth is 13+ billion years out of date. That's plenty of time for stars to form and die, create white dwarfs, and generally not look anything like your star map.

And you'd have to be going at one hell of a good clip - even at only c, the universe has a 13-billion-odd year head-start on you.

SJQ

Holy crap! Lookit all the turtles!!!
 
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planetling

Guest
This is very difficult for me to conceptualize. I am understanding the curvature of space to be caused by gravity. But if we were somehow able to jettison out 13+ billion years toward the beginning of the universe (in my mind, that would be toward the outer edge) we would also have escaped this curvature on the ride over. The curvature exists because of time and gravity. If we are sitting on the edge of our universe, I would tend to believe that we should also be able to cross this edge and into another realm beyond our single physical universe, if speeds of that magnitude were possible. So, the curvature only exists based upon a point of view. And that is my question?
 
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origin

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The short answer is that you can't get there from here...

Imagine a balloon representing our universe, and an ant on the balloon to repersent us. Now start inflating the balloon so it expands (like our universe) every point will move away from each other. So if we have a speedy ant that can run faster than the expansion of the surface, how long untill it reaches the edge? Of course the answer is never, because there is no edge.

Careful not to take this analogy to far, because we don't live on a 3d surface (2 spatial, 1 time) we live in 4d space (3 spatial, 1 time).
 
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centsworth_II

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planetling":1myofccq said:
...if we were somehow able to jettison out 13+ billion years toward the beginning of the universe...
If you were to jettison yourself out to a galaxy thirteen billion light years away, you would not find yourself in a baby galaxy at the edge of the universe. You would find yourself in a 13 billion year old galaxy in the center of the universe.

The only reason we see young galaxies formed at the beginning of the universe is that they have expanded so far from us that light from their formation 13 billion years ago is just reaching us. Astronomers in those distant galaxies would look back at us and see light that left our galaxy 13 billion years ago and to them it would look like we are at the edge of the universe.

The "baby" galaxies we look at at the "edge of the universe" have aged 13 billion years since the light we see them by left them. Just as the light that they see us by left our galaxy thirteen billion years ago when it was a baby. So one civilization's "edge" is another civilization's here and now.

If you could instantly transport to any spot in the observable universe, you would find yourself in a 13 billion year old star system looking out at younger and younger star systems the farther out you look. To every civilization in the universe, it looks like they are living in the present and the edge of the universe is 13 billion years away in all directions.
 
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MeteorWayne

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Very well put C_II, one of the clearest I've ever seen.
 
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captdude

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So let me see if I understand this correctly. Lets say the "big bang" took place exactly 13 billion years ago. This means that our observable "light bubble" measures 13 billion light years across. If I comprehend your analogy correctly - then you are saying that the expansion of the total universe (observable & non-observable) has taken it far beyond our 13 billion light year measurment. (you say another civilization at the edge of our observable universe would have their own 13 billion light year light bubble)
So I guess my question is, are you implying that the size of the universe extends beyond our bubble of light and that as time goes by more of it will be revealed?
 
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SJQ

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Yes. We can see only the visible universe, that from which light has had time to travel to us since the creation event some 13 billion years ago. There is no reason to limit the actual universe just to what we can see; the creation event doesn't care about how big our visible universe is at any time after it happens.
 
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Mee_n_Mac

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captdude":244lc6f4 said:
So I guess my question is, are you implying that the size of the universe extends beyond our bubble of light and that as time goes by more of it will be revealed?
It seems likely that the universe extended beyond our visible universe though there's no way to prove it (though some have hinted at such a proof). However due to the accelerating expansion of the universe, portions of which are exceeding c[sub]0[/sub] recessional velocity, we'll actually see less of the universe as time goes by. It's thought that if enough time goes by we'll eventually only be able to see our local cluster of galaxies.
 
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nec208

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mcarans":2733e9bu said:
If a space ship was able to travel faster than our universe is expanding and thus reach the edge, what would happen to the ship?

This is some thing I want to know too!! But believe it cannot be answered has no one knows the shape of the universe if it is flat,round or box like or what ever shape.

The expanding universe is the stars and galaxies are expanding .Before the big bang the universe was dark no stars,gas or galaxies .In the future all the stars will die out and the universe will be dark.

If it is proven the universe is like earth getting bigger and bigger than the question is what is out there a higher plane .


And the next question are there other universe out there we cannot see or get too .No one knows the shape of the universe or what it was like before the big bang.
 
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SpeedFreek

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Our observable "light bubble" measures 92 billion light-years across.

We detect Cosmic Background Radiation coming at us from all directions. So, if we consider the CBR that comes from opposite directions, we are detecting radiation emitted from regions of the universe that are now 92 billion light-years apart.

Please read the PDF article linked in my signature!
 
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nec208

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SpeedFreek":zgwh12xs said:
Our observable "light bubble" measures 92 billion light-years across.

We detect Cosmic Background Radiation coming at us from all directions. So, if we consider the CBR that comes from opposite directions, we are detecting radiation emitted from regions of the universe that are now 92 billion light-years apart.

Please read the PDF article linked in my signature!

The detecting radiation emitted not from the observable universe may prove the universe is flat and not round and may disprove other universe we cannot see or get to.
 
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Gravity_Ray

Guest
I am not sure if its even provable that there was light right from the begining of the universe! It took some amount of time (probably a very long time in human terms) for stars to form and emit light. So the universe is larger than the observable part of the universe.

"edge" is a human term, and may not apply to the universe.
 
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origin

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nec208":2fobulee said:
The detecting radiation emitted not from the observable universe may prove the universe is flat and not round and may disprove other universe we cannot see or get to.
Opps, this doesn't make sense. The part of the universe that is not observable is not observable because there is no light from that distance reaching us. So by definition, no radiation from the non-observable part of the universe could reach earth.
 
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Mee_n_Mac

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Gravity_Ray":thnb0157 said:
I am not sure if its even provable that there was light right from the begining of the universe! It took some amount of time (probably a very long time in human terms) for stars to form and emit light. So the universe is larger than the observable part of the universe.
I think it's understood that the was no "light" (that we could "see" today) at the beginning of the universe. Any photons would be absorbed before they could travel freely. It wasn't until about 400,000 yrs after the BB that they could do so. After the recombination period the universe was dark until stars ignited ... about 200 Myrs later (I think).

http://en.wikipedia.org/wiki/Timeline_o ... C000_years
 
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nec208

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origin":1er84b8n said:
nec208":1er84b8n said:
The detecting radiation emitted not from the observable universe may prove the universe is flat and not round and may disprove other universe we cannot see or get to.
Opps, this doesn't make sense. The part of the universe that is not observable is not observable because there is no light from that distance reaching us. So by definition, no radiation from the non-observable part of the universe could reach earth.
oops I thought he was saying we where getting radiation coming from empty space no stars,gas or planets so on and was a mystery to scientist.
 
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