What's At The End Of The Universe

[Turtleguy]

I found a video on the net that was about the universe. It showed a pic the Hubel Telescope took of the universe 47 billion lightyears away. The end of the uiverse. Yes the universe is 47 billion light years in radius. I always thought there was no end. Now that I know there is an end I wonder, what is at the end? If we flew past the end where would we be? Would we be back at the begining?

[Adcox]

I found a video on the net that was about the universe. It showed a pic the Hubel Telescope took of the universe 47 billion lightyears away. The end of the uiverse. Yes the universe is 47 billion light years in radius. I always thought there was no end. Now that I know there is an end I wonder, what is at the end? If we flew past the end where would we be? Would we be back at the begining?

Good question maybe another dimension

[Aubrienne_Ellyrias]

show the video on here you!!!

[leadbelly]

Indeed. We may have to go to more dimensions, to liftoff from the observed universe. Is there an edge? Remember, we are seeing a snapshot in time, when we look billions of lightyears away. The shape of a monolitihic universe may be roundish, or discoidal. It appears that way from the distribution and density of matter and energy.

Here is a basic lecture on the early universe, which actually only touches on the issue of beyond the edge. But, the current theory is that we live in a "flat" universe, which may have expanded into a larger region or dimension. What we observe may only be a portion of a vastly larger universe.

Link (1 hr.)

[StarMountainKid]

Here's a link as to the size of the universe:

http://www.space.com/scienceastronomy/myst...day_040524.html

The universe is 13.7 billion years old, light from the earliest galaxies have been traveling to us for at least 13 billion years, so we'd think the diameter of the universe would be 13.7 x 2 = 27.4 billion years. However, the universe has been expanding since its beginning, so the distance covered by the light gets increased by this expansion. So that early galaxy is now 78 billion light years away. It's as if you mark one inch on a rubber band, streach the rubber band and now that one inch measures three inches. The diameter of the universe is 158 billion light years looking 90% of the way back in time. This is from the link.

This would be the diameter of just the observable universe. The actual size of the total universe may be 10 - 1000 times larger.

[MIB-Agent]

The Universe has no edge so it therefore has no end.

[ex infernis]

The Universe has no edge so it therefore has no end.

and you know this how?

[Pandora7321]

I thought the universe had no center and no edge. Before you ask me how I know, I don't. I just read that. I don't know how true or not it is.

[Altheia]

http://www.unexplained-mysteries.com/forum...showtopic=84457

the end of the universe..sounds so decisive.

[Siara]

I picture it as some sort of space warp... You go to the western edge of the universe, move forward, and suddenly you're on the eastern edge. You go to the northern edge of the universe, move forward, and suddenly you're on the southern edge (using a terrestrial direction system 'cause I don't know a more sophisticated system).

[majin nemesis]

the begining of nothing or the beginning of something

[Captain Kolak]

Our univers does not have a clearly defined edge. It is just energy and light expanding. And it is becoming more dilute the further it expands. Like if you drop a rock into a calm pool. The waves are still present far away but hard to notice. Until they die away. And for it to expand, it must expand into something. And in this case nothing is something (Space).

[Picturesque Orion]

I found a video on the net that was about the universe. It showed a pic the Hubel Telescope took of the universe 47 billion lightyears away. The end of the uiverse. Yes the universe is 47 billion light years in radius. I always thought there was no end. Now that I know there is an end I wonder, what is at the end? If we flew past the end where would we be? Would we be back at the begining?

Dont take everything you see too seriously, just remember that it is all theories so we aint sure if it is true or not. Modern day scientist cant say the exact size of the universe. Modern day scientists can't say that the universe is infinite or finite, so they make theories. The hubble thing.... it is just a theory, so dont be so sure that there is an end. There is also a theory that the universe is infinite, so it never ends, but this isnt secure, because it is just a theory. The 47 billion light year size of the universe is just a theory, as I said before, modern day scientists can't say the exact size of the universe if it is finite.

We are free to think and believe what we want, thats why theories are there.

[Picturesque Orion]

Our univers does not have a clearly defined edge. It is just energy and light expanding. And it is becoming more dilute the further it expands. Like if you drop a rock into a calm pool. The waves are still present far away but hard to notice. Until they die away. And for it to expand, it must expand into something. And in this case nothing is something (Space).

I totaly agree with this, the universe is just a huge pile of matter, and like all matter it has a limit, coz if you say that matter is infinite than you must say the a simple football is infinite in size. So........ this matter ( the universe ) must be somewhere to exist no? Well this somewhere is Space. What is space? Space is the emptyness where the universe exists, the universe like all matter must exist somewhere, this somewhere is space. So yes space is nothingness, emptyness filled with a huge amount off matter and energy ( the universe) so if you take a super fast space craft and travel to the end of the universe you will be able to go on, nothing is gonna stop ya, but since you left the universe you will be travelling in nothingness, emptyness...... everything will be black because not even light will be there. So... if space is the emptyness and nothingness where the universe resides then we can say that space is infinite. How could you say that emptyness is finite?? How could someone say that complete nothingess has an end? So I think that space is the infinite one, the universe wich is matter in space is finite because all matter has to end. A football end somewhere, a pencil end somewhere, a house ends somewhere, the earth ends somewhere in space too, it's size cannot be infinite because then only the Earth would exist.

[Cadetak]

Its not that the universe ends its just that there comes a point where there is no more matter(stars, planets, etc.) and the point where no energy has reached. If you where to travel to the point where the universe 'ends' you wouldn't hit a wall or anything you would just find yourself in a place where there is nothing.

Or at least thats what I think...or what I think I think.

[Harte]

Many seem to be under the false impression that "the Universe" is just the matter and energy. It's not, it's the space too.

So, no, you wouldn't find yourself somewhere where there is only space and no matter or energy - that's still the universe and there is no such "empty" place in it anyway, if the Big Bang theory is correct.

Even empty space is boiling with the creation and almost instantaneous destruction of particles of matter and antimatter, if you look on a small enough scale.

Given the big bang, which created the universe (and this includes the space as well as the matter/energy,) if there were an edge of the universe, it would be just as dense with matter/energy as any other place. After all, that part of the universe will have started out in exactly the same point as all the rest of the universe, IOW, the cosmic egg.

One way to think of an "edge" of the universe is to consider a singularity to be the edge. It is, by definition, anyway.

Another way is to think of the edge as the beginning or the end (if there ever is an end) of the universe in time. After all, the universe is composed of spacetime, right?

Whether the universe actually has an edge in the usual sense depends solely on the spacetime geometry.

The idea that one could travel outward and end up back home corresponds to a closed universe (a gigantic black hole, IOW,) which has a spherical shape. This sort of universe is bounded, so I suppose you could say it has an edge, but you can't see it unless you step up into higher dimensions.

A universe without an edge (in 3-D,) infinite IOW, corresponds to an open geometry - sometimes referred to as hyperbolic.

The hyperbolic and spherical shapes are not 3-D shapes, they are 4-D shapes of spacetime geometry, which is why you end up back at home in the closed universe.

Kind of complicated but if you think on it, you can get it.

Harte

Edited June 10, 2007 by Harte

[Picturesque Orion]

Many seem to be under the false impression that "the Universe" is just the matter and energy. It's not, it's the space too.

So, no, you wouldn't find yourself somewhere where there is only space and no matter or energy - that's still the universe and there is no such "empty" place in it anyway, if the Big Bang theory is correct.

Even empty space is boiling with the creation and almost instantaneous destruction of particles of matter and antimatter, if you look on a small enough scale.

Given the big bang, which created the universe (and this includes the space as well as the matter/energy,) if there were an edge of the universe, it would be just as dense with matter/energy as any other place. After all, that part of the universe will have started out in exactly the same point as all the rest of the universe, IOW, the cosmic egg.

One way to think of an "edge" of the universe is to consider a singularity to be the edge. It is, by definition, anyway.

Another way is to think of the edge as the beginning or the end (if there ever is an end) of the universe in time. After all, the universe is composed of spacetime, right?

Whether the universe actually has an edge in the usual sense depends solely on the spacetime geometry.

The idea that one could travel outward and end up back home corresponds to a closed universe (a gigantic black hole, IOW,) which has a spherical shape. This sort of universe is bounded, so I suppose you could say it has an edge, but you can't see it unless you step up into higher dimensions.

A universe without an edge (in 3-D,) infinite IOW, corresponds to an open geometry - sometimes referred to as hyperbolic.

The hyperbolic and spherical shapes are not 3-D shapes, they are 4-D shapes of spacetime geometry, which is why you end up back at home in the closed universe.

Kind of complicated but if you think on it, you can get it.

Harte

But the Universe has to be somewhere no? Welll we call that somewhere space. As simple as that.

Before the Big Bang all the matter or the universe was compressed in one place, like in one huge ball, but this compressed matter had to be somewhere to exist, this somewhere is what we call space, when the Big Bang occured alll this matter expanded in that somewhere wich we call space.

Edited June 10, 2007 by Ghostkol

[jesspy]

whats at the end of the universe? a brickwall lol

kidding

wouldnt it be the start of another universe?

Edited June 10, 2007 by jesspy

[Harte]

But the Universe has to be somewhere no? Welll we call that somewhere space. As simple as that.

Nope, it's not as simple as that. The universe includes the space it occupies. When they say "the universe is expanding," what they mean is that space itself is expanding, not just that the materials that are floating in space are moving away from each other.

Before the Big Bang all the matter or the universe was compressed in one place, like in one huge ball, but this compressed matter had to be somewhere to exist, this somewhere is what we call space, when the Big Bang occured alll this matter expanded in that somewhere wich we call space.

Nope. Space was part of the "cosmic egg" that exploded. IOW, space itself exploded outward from this.

It ain't my fault that you don't comprehend. Truth actually is stranger than fiction.

Harte

Edited June 10, 2007 by Harte

[Captain Kolak]

What is the universe, energy expanding.......... (that includes matter), what is space. Nothing. So the universe is expanding into nothing but that nothing is figuratively SOMETHING.

[War Eagle]

Only a few years ago scientists/Astronomers had to come clean in admitting that they got it completely wrong about Pluto being a planet... and thats just our solar neighbor?!

It's also been said that the universe is expanding at faster than the speed of light and now they apparently have that wrong too.

Now they claim to know whats outside the known universe?!...

[Leonardo]

There is no end of the universe. It's current expansion is happening everywhere simultaneously. To state that the universe 'expanded from a centre/cosmic egg' is misleading, because here never was a centre/cosmic egg for it to expand from, or rather the centre/cosmic egg was everywhere at once.

From our perspective, using radio-astronomy, it appears the universe expanded from a central point some few billions of years ago and is now a certain size based on the rate of universal expansion. However, go to any other point of the universe (it would have to be relativistically far away from here) and you would find the universe expanding from another centre based on the radio-astronomical observations from there.

The size of the universe is defined for us by the speed of light and the rate of expansion. You could go to the current edge of the observable universe and it would still be the same size in all directions.

whats at the end of the universe? a brickwall lol

kidding

wouldnt it be the start of another universe?

How about the start of our own

Edited June 11, 2007 by Leonardo

[InnerSpace]

Only a few years ago scientists/Astronomers had to come clean in admitting that they got it completely wrong about Pluto being a planet... and thats just our solar neighbor?!

It's also been said that the universe is expanding at faster than the speed of light and now they apparently have that wrong too.

Now they claim to know whats outside the known universe?!...

LOL REBEL

[Harte]

What is the universe, energy expanding.......... (that includes matter), what is space. Nothing. So the universe is expanding into nothing but that nothing is figuratively SOMETHING.

Sorry, but that's just not the case. Space is itself expanding. It is the expansion of space itself that causes the galaxies to get further and further apart from each other. Space is four dimensional (spacetime.) Space is not expanding into anything that we can conceive of. It's certainly not expanding into more space. If you must visualize the universe expanding into something, then you're gonna have to somehow imagine the geometry of higher dimensions.

Only a few years ago scientists/Astronomers had to come clean in admitting that they got it completely wrong about Pluto being a planet... and thats just our solar neighbor?!

Rebel,

The Pluto thing is only the result of the refining and updating of the definition of what a planet actually is. Nobody was ever "wrong" on this. Going by the original definition, Pluto was a planet. Now it's not. That's all.

It's also been said that the universe is expanding at faster than the speed of light and now they apparently have that wrong too.

Now they claim to know whats outside the known universe?!...

Nobody has claimed to "know" anything of the sort. But, like everything else in Cosmology, there are various theories about it.

You know, I love your link, and I love the fact that you included it. Bravo.

But if you had read what is at the link, you would have seen that the universe actually is expanding faster than light:

However, for the simplest interpretation of your question, the answer is that the universe does expand faster than the speed of light, and, perhaps more surprisingly, some of the galaxies we can see right now are currently moving away from us faster than the speed of light! As a consequence of their great speeds, these galaxies will likely not be visible to us forever; some of them are right now emitting their last bit of light that will ever be able to make it all the way across space and reach us (billions of years from now). After that, we will observe them to freeze and fade, never to be heard from again.

SNIP

To answer the broader question in detail, we need to specify what we mean by the universe "expanding faster than the speed of light." The universe is not a collection of galaxies sitting in space, all moving away from a central point. Instead, a more appropriate analogy is to think of the universe as a giant blob of dough with raisins spread throughout it (the raisins represent galaxies; the dough represents space). When the dough is placed in an oven, it begins to expand, or, more accurately, to stretch, keeping the same proportions as it had before but with all the distances between galaxies getting bigger as time goes on.

The bottom line is that different pairs of galaxies are moving at different speeds with respect to each other; the further the galaxies are, the faster they move apart. So when we ask whether the universe is "expanding faster than the speed of light," I am going to interpret that to mean, "Are there any two galaxies in the universe which are moving faster than the speed of light with respect to each other?"

SNIP

In light of this, a more fair question to ask might be whether or not any galaxies in the visible universe (the part we can currently see) are moving away from us faster than the speed of light.

Surprisingly, the answer is yes! Ned Wright's Cosmology Tutorial has a calculator which allows you to compute many quantities, including distance, for different models of the universe and for galaxies at different "redshifts" from us (the redshift is an experimentally easy-to-determine property of the galaxy's light that tells us how much the universe has stretched between the time the light was emitted and the time it was received). Using the best observationally-determined values for the universe's rate of expansion, acceleration and other parameters (which are the default inputs for the calculator), I found that if you use a value of around 1.4 for z (the redshift), you get the required distance of 4,200 megaparsecs. Therefore, any galaxy with a redshift greater than 1.4 is currently moving away from us faster than the speed of light.

Can we see these galaxies? Yes, we certainly can! Bright galaxies are regularly detected out to redshifts of a few; a redshift of 1.4 isn't really that much. For example, here are some pictures of quasars (galaxies with extremely active black holes in their centers) with redshifts around 5. We can even see light (although not individual objects) all the way back to a redshift of 1000 or so. (This light is referred to as the Cosmic Microwave Background and was emitted around 380,000 years after the Big Bang, right after the Universe had cooled down enough for light to get through all the intervening matter.) Meanwhile, the numbers spit out by the calculator tell us that for a galaxy with a redshift of 1.4, the light we are currently seeing from this galaxy was emitted around 4.6 billion years after the Big Bang, when the Universe was already quite well-developed.

You might be wondering how we could possibly see a galaxy that is moving away from us faster than the speed of light! The answer is that the motion of the galaxy now has no effect whatsoever on the light that it emitted billions of years ago. The light doesn't care what the galaxy is doing; it just cares about the stretching of space between its current location and us. So we can easily imagine a situation where the galaxy was not moving faster than the speed of light at the moment the light was emitted; therefore, the light was able to "outrun" the expansion of space and move towards us, while the galaxy moved away from us as the universe expanded. Keeping in mind what we learned above -- that farther objects recede faster in a proportionally stretching universe -- we can immediately see that right after the light is emitted, the galaxy is moving away from us faster than the point at which the light is located, and that this disparity will only increase as time goes on and the galaxy and light separate even more. Therefore, we can easily have a situation where the galaxy keeps on moving away faster and faster, eventually reaching or exceeding the speed of light relative to us, while the light which it emitted billions of years ago leisurely coasts on, never having to move across a region of space that was stretching faster than the speed of light, and therefore reaches us eventually.

Source is the last link you gave.

Einstein showed us that all motion in space is relative. There are visible galaxies in the night sky that are actually moving away from us at speeds faster than light. To them, we are the ones moving away. To their nearby neighboring galaxies, they do not appear to be moving nearly as fast as we see them move.

The last link you gave, the one I quoted from, tells you exactly why farther galaxies have a higher velocity realtive to our position of observation than galaxies which are nearer to us.

Harte

[QuickSilver2005]

Wow, that's quite interesting. I've always imagined a boundless space occupied with energy/matter moving outwards. With that in mind I thought once you get past the outer edge of the expanding matter/energy and keep a pace that is faster than the expansion that you may be able to look back and watch the universe expand as a whole. That would be one site to see. However being that I've never actually researched into the field, that is just an idea I had. Harte, you wouldn't happen to have a link or two I could check out perhaps? I'm very interested in knowing more about this. I may have misread, but If I understand correctly, you are saying that the "space" is attached to the matter/energy that is expanding outward as in they are "one and the same"? Correct me if I got that wrong, however that's pretty cool if I do say so myself.