What is infinity? Is the universe infinite?

Question

Everything has an end, right? What is beyond the sky? Where does the universe end? Where does it begin?

There is no good or right answer for this question. Any speculations are appreciated, scientific or philosophical.

Answer 1

I don't think the universe is infinite. I think the multi universe theory might explain how there could be something beyond our universe,(the multi universe theory stating that there is more than one universe) but then what is beyond that? This is a tough question, because no one knows for sure. But as an avid Carl Sagan and Stephen Hawkings reader, thanks for giving my brain something to do.

Answer 2

The beginning of the universe is actually at the end of it. When you look up at the stars in the night sky, what you're often seeing is ancient light, depending on the star. Some are so far away that the light you see now left the star when Columbus was still sailing the seas, taking all that time to travel here and hit your eye.

The Big Bang exploded outwards, but the light from it never dissapeared. It just kept going. The farther into space you look, the older the light is, hence the younger the universe is. At it's most outer edges is the beginning.

What's beyond, I don't know.

Answer 3

There has to be an end; if there is a start there must be an end. It's funny, I put a question about this the other day. There really is no sure answer; but logic dictates that there must be an end of some sort.

As one of my answers put it, perhaps it's a bubble form. I agree that it may be and the cycle has it's beginning and end; although, the cycle itself may be infinite. But that has to have an end also. I guess it's all about what we find as an end; the beginning of something new? Here we go again.

Nice to find a great mind out there searching.

Answer 4

The Universe is probably limited in size though it has no edges but thats something you can read about in other questions.

Infinity just means a boundless number or size. For example, 1, 2, 3 are integers - there are an infinite number of them though you couldn't possibly write them down - in fact no matter how many you wrote, when you were done, at the end of your life you'd be EXACTLYas close to infinity as you were when you put '1'.

The observable universe seems to be 13.7 billion light years across. As space is not limited to the speed of light the actual universe that light rests in may be millions of times larger.

Answer 5

There are different kinds of infinity.

One is described as "finite and unbounded". An analogy would be a sphere. A sphere has finite volume, but a two dimensional creature moving on the surface would never reach a boundary of any kind. Hence, "finite and unbounded".

Another is described as "infinite and unbounded". An analogy would be a three-dimensional hyperboloid ("saddle shape"). The surface extends to infinity in any direction; and a two dimensional creature moving on the surface would never reach a boundary of any kind. Hence, "infinite and unbounded."

There are models of the universe which employ both concepts. The easiest one to imagine is the finite and unbounded model.

Instead of a three dimensional sphere, you have to imagine a fourth dimensional sphere - that is, three dimensions curved in four. Like the three dimensional sphere, it is finite in four dimensions. But a three dimensional creature (like you) moving along the "surface" (which we call "space") will never reach a boundary of any kind.

In this way, the universe can be thought of as being finite and infinite at the same time. You just need an extra dimension in which it can be curved into a finite "shape". Then the "surface" (space) has no end, just as the surface of a three dimensional sphere has no end.

Big Al Mintaka

Answer 6

Infinity is this:

9.9 is a little less than 10

9.999 is closer to 10.

9.999... with a million more 9s is really close to 10 but not exactly 10.

9.999... with an infinite number of 9s is exactly 10. Infinity is the number of 9s you need to the right of the decimal place to make that number equal 10.

Answer 7

infinity to me is it goes on forever without end. Now this is hard to imagine and hard to fathom but here is how I think it works. Space was said to have started with the big bang, so, i think what they are saying is the universe continues to expand and continues with several ongoing big bangs so to speak. There is so much out there that we are unaware of. I mean they are still discovering new animals and species of animals here on earth.

Answer 8

Yes. The universe is infinite.

Answer 9

There is no "end" to the universe in physical terms. Its like travelling from point x on a three dimensional circle---

Answer 10

Probably unheard of planets and species that humans only fantasize about.