how big is the universe? if you carried on going through space would it ever end?

Answer 1

The universe may or may not be infinite. Either way, it has no boundary. If you could go faster than the speed of light (you can't really, just hypothetically speaking) long enough, you end up back in the same place if it's finite. You'd actually return before you left, but that's another story. Yes, it sounds weird, but that's the way general relativity works. Really. Quantum mechanics is even weirder.

Followup: Incidentally I'm not restricting my answer to only that portion of the universe which is visible, which is limited by the age of the universe and the finite speed of light. When many people say "universe", they really mean "visible universe". The entire universe, though, is likely immeasurably larger. Since we can't see it, though, this sometimes leads to debates about the meaning of it all. You know, if a tree falls and no one hears it kinda stuff.

Answer 2

It has been said that because our universe creates its own "space and time" it is expanding into pure nothing. Is there a possibility that this "nothings"' main attribute is that of a perfect vacuum pulling the universe apart like a balloon inside a bell jar when the air is removed?


The Answer
Interesting idea, which may help explain why the universe appears to be expanding at an ever increasing rate. If I can extend your logic - an infinitely dense point of matter appears in an otherwise perfect vacuum state. An event of some sort causes that point to begin to expand very rapidly, overcoming whatever initial gravitation pull would keep the point of mass together. As the new universe continues to expand, there is less and less gravitational pull to bring all of this mass back to its origin. If the pulling force outward is constant and the gravitational pull continues to decrease, the expansion rate will continue to increase. This is a valid line of thought, however, let's say one inserts a puff of gas into an evacuated bell jar. The gas will quickly expand, but the more volume it fills, the slower the expansion rate (at least in terms of the radius of the expansion; maybe the change in volume per unit time is constant or increases?).
Apart from that potentially damaging argument, there is the issue of the definition of "universe." Or universe, by one definition, is everything. There is nothing beyond or outside of it, not even the empty space-time we can conceive of as perfect space, so there would be no vacuum into which the universe could expand. This may seem a bit of a paradox, as we can always imagine something outside of our house or our solar system, but then it really becomes a question of philosophy as much as science.

Answer 3

Bigger than any of us could even begin to imagine.

No, if you carried on going through space you would never reach the end - not because it's infinite (it's NOT even though loads of people on here claim it is), but because the way in which space-time warps means you would always end up back where you started (in several billion, billion years).

Answer 4

Current theory is that the universe is aproximately 92 billion light years across and expanding. Put another way, multiply incredibly large by gigantic and then multiply that by stupendously enormous to the power huge.

Wikipedia says;

The comoving distance from the Earth to the edge of the visible universe is about 46.5 billion light-years in any direction; this is the comoving radius of the visible universe. It is sometimes quoted as a diameter of 92-94 billion light-years. Since the visible universe is a perfect sphere and space is roughly flat, this size corresponds to a comoving volume of about 4/3 π R3 = 4.0×1032 cubic light-years or 3.4×1080 cubic meters.

The figures quoted above are distances now (in cosmological time), not distances at the time the light was emitted. For example, the cosmic microwave background radiation that we see right now was emitted about 13.7 billion years ago by matter that has, in the intervening time, condensed into galaxies. Those galaxies are now about 46 billion light-years from us, but at the time the light was emitted, that matter was only about 40 million light-years away from the matter that would eventually become the Earth. See comoving coordinates.


Misconceptions
Many secondary sources have reported a wide variety of incorrect figures for the size of the visible universe. Some of these are listed below.

13.7 billion light-years. The age of the universe is about 13.7 billion years, and nothing travels faster than light; does it not follow that the radius of the observable universe must be 13.7 billion light-years? This reasoning might make sense if we lived in the flat spacetime of special relativity, but in the real universe, spacetime (not space!) is highly curved at cosmological scales, and light does not move rectilinearly. Distances obtained as the speed of light times a cosmological time interval have no direct physical significance. [3]
15.8 billion light-years. This is obtained in the same way as the 13.7 billion light-year figure, but starting from an incorrect age of the universe which was reported in the popular press in mid-2006 (e.g. [1] [2] [3]). For an analysis of this claim and the paper that prompted it, see [4].
27 billion light-years. This is a diameter obtained from the (incorrect) radius of 13.7 billion light-years.
78 billion light-years. This figure, as mentioned above, is a lower bound on the size of the whole universe, and has nothing to do with the size of the visible universe.
156 billion light-years. This figure was obtained by doubling 78 billion light-years on the assumption that it is a radius. Since 78 billion light-years is already a diameter (or rather a circumference), the doubled figure is meaningless even in its original context. This figure was very widely reported (e.g. [4] [5] [6]).
180 billion light-years. This estimate accompanied the age estimate of 15.8 billion years in some sources; it was obtained by incorrectly adding 15% to the incorrect figure of 156 billion light-years.

Answer 5

If you went fast enough and far enough yes you would come to an end to the universe, and a beginning to the open void of space.

Answer 6

The simple answer to your question is nobody really knows. Seeing as the technology it takes to travel across the universe is further away than the time you have left in your life there is no point even thinking about it.

Answer 7

The introduction begins like this:

"Space," it says, "is big. Really big. You just won't believe how vastly hugely mindboggingly big it is. I mean you may think it's a long way down the road to the chemist, but that's just peanuts to space. Listen ..." and so on.

Answer 8

It has an end just like a black hole has a boundry. The universe is massive enough to bend space back onto itself causing an event horizon.

Answer 9

the universe is supposed to be always expanding some think its slowing. so if you were travelling like 1000 times the speed of light you could in a couple of million catch up to the expanding boundary of the universe just tell me what you find ok

Answer 10

I even have travelled previous the reaches of our ecosystem and totally understand that infinity is the only be conscious that sums it up so nicely. What fills the area is the wish of love and peace... and a good neck chew.