is space infinate?

[zehydra]

Slight problem. The eye is known to be sometimes incorrect (optical illusions).
And one other thing Martymer, you might be able to detect the movement of contents within the universe, but you could never know whether or not the universe is expanding, because the Universe is mostly made up of stuff we can't see (dark matter/dark energy).

 

[beddo]

snip

I think our arguments are largely pointless. Yes you can manipulate number sets and display them in any way you choose but you can do so arbitrarily.

I do see what you are saying about spacing though, if any spacing is larger than 0 the whole set will be an infinite line. Infinity is not a set point of course, and there are different sizes.

I think that if we say the universe expands from a single point at a given speed and is accelerating then it is not infinite. That is not to say that it has boundaries, it may be able expand to infinity as there is nothing restricting it.

 

[beddo]

Yes. Of course it is. It's infinite and expanding.

If it's infinite then how is it getting bigger?

Infinite doesn't mean it's restricted to a certain figure.

What's infinity + 1?

You can't have infinity + 1. Infinity is not a number in that sense, it has its own set of rules that are different to the regular numbers we deal with.

There are different sizes of infinity but you cannot manipulate any of them using normal mathematical operations.

It's quite possible to manipulate infinity using normal operations, it's just that most of the answers are just infinity again.

infinity + 1 = infinity
infinity + infinity = infinity
infinity * 2 = infinity
infinity * infinity = infinity
infinity / 2 = infinity
infinity / 0 = infinity (zomg division my zero!!!)
infinity^2 = infinity

A few give different answers.

infinity * 0 is undefined, as it could be any number.

And for any given infinity, which we will call x for now, 2^x > x

It is pointless using normal operations on infinity because they have no effect. The only exception is multiplying or dividing by zero which just gives you a result of undefined.

infinity / 0 is perfectly well defined in number systems where infinity exists as a number.
And, as I said, 2^infinity gives a greater infinity than you had before.

And yes, many operations with infinity are essentially pointless to do for their own sake, but that doesn't mean you can't do them, as you claimed before.

Okay, you can do them but they are irrelevant, you only really need to use the algebra of limits.

 

[Datalord]

You're going to want to look it up if you want a real answer. Best I can so is this:

If you go in a staright line, you'll eventually get back to where you started.

Yes. Of course it is. It's infinite and expanding.

That doesn't work. If it's infinite, it can't expand.

That's not true. Space isn't 'nothing' per se. It's generally empty. I tend to think of the area outside the universe to be void, nothingness. The universe can expand into this area, so the universe can grow, which means the universe can expand without having an area to grow in to.

Space, technically though might not be infinite... it could have stopped growing, or be contracting. It's a bit of a confusion really.

You're confusing space and the universe

Our universe is a collection of all the matter and energy involved in the big bang and the space they encompass, because of positive entropy in that space, the universe expands, when entropy reaches 0, the universe will stop expanding and contract (and we all die).

Outside of our universe is more space, and a theoretically infinite number of other universes.

Space, however, is simply infinite.

 

[Guy32]

This is f***in with my mind. Screw it.

 

[NotAProdigy]

Some people need to read a little something called Entropy.

Yes it's expanding, and it'll continue to expand. In fact, the rate of expansion is accelerating because gravity isn't strong enough to hold everything in place. Galaxies will eventually go so far apart that it'll be a vast cold and isolated place which almost no life can exist. It's a little depressing, but that's the reality of it.

If the universe is ever expanding, which science says it is, then no, it isn't. Infinity can't be expanded because you could reach the point of expanse, therefore making it finite.

Science never said it's infinite, they said it is approaching infinity (a very important concept in mathematics). And in essence, unless there's something to stop the expansion it'll continue to approach infinity.

Yes. Of course it is. It's infinite and expanding.

...then what is it expanding into?

OT: No, it's still expanding from the Big Bang.
The question is what lies beyond

If you believe in the multiverse theory, all the universes are contained within their own possibilities.

 

[Julianking93]

I don't know. Common logic would lead me to believe that nothing is infinite and it has to end somewhere, but where?

What's at the edge? Is it just blackness? Would it just be like a wall that you can't pass through? Would I become a Reaver like in Firefly if I went to the edge?

It's possible that we are unable to get to the outside of the universe. Think of before we knew the world was round and before we could get into space. You could try and see everything by walking but you'd only ever be able to see the surface of the earth.

We don't truly know if there is anything outside the universe, it may be in another dimension or any number of possibilities. We're currently mostly focusing on the observable universe, hopefully the LHC will give us some more answers.

Perhaps, or it would create a black hole and suck up this universe! (No, just kidding)

But that is an interesting way of looking at it. I do believe in the multi-verse theory and I think that it would be awesome if true, but I just don't know, and neither does anybody else.

 

[thiosk]

Because of the peculiarities about the expansion of empty space and the speed of light, its actually not currently possible to answer this question. We're currently thinking No, but the concept of an effective light horizon means we may not simply be able to observe the full extent of the universe.

 

[Maze1125]

I think that if we say the universe expands from a single point at a given speed and is accelerating then it is not infinite.

It's not the edge of the universe that has a set speed, but how quickly two points of a set distance apart are moving away from each other.

If you double the distance between the two points, you double the speed at which they move away from each other. Two points on the other side of the room will take years to move any measurable distance, even with the most precise scientific measuring equipment. Yet galaxies billions of light-years away are moving away from us at thousands of miles a second.

All the points in our universe existed even when it was a singularity, if all those points tried to move away from the next one by even a fraction of a fraction of a fraction of a millimetre then the universe could jump from being a singularity to being of infinite size instantly.

 

[Cuddly Knife]

I don't think the universe is infinite, because nothing is. But I wouldn't really know anyways, as would no other person ever.

One thing that has always bothered me about the Hubble Deep Field image is if there are planets, stars, quasars, nebulae, galaxies, and other random outer space stuffs, then wouldn't most of that stuff be blocking out anything behind it, within the telescopes field of view? How, with our billions of stars in our galaxy, can we see beyond them to other galaxies? How do we get images like these?

Spoiler

Spoiler

If they are able to look back in time, then why can't they point the lens the opposite and see the future? Silly question, but really, why don't they ever look to the other direction opposite the center of the Universe? I mean, they say that we are near the edge of the universe, or at least on one of its outer arms, so what lies in that direction?

It doesn't matter anyways. We are too primitive to ever understand the complexities of it all. We'll never know unless another being who already knows these things were to tell us.

 

[Maze1125]

What's at the edge? Is it just blackness? Would it just be like a wall that you can't pass through? Would I become a Reaver like in Firefly if I went to the edge?

"The Edge" referred to in Firefly was in fact only the edge of a solar-system, not the universe.

From the sounds of it, you haven't watched the film Serenity which, if you didn't know, is a continuation of the series.

 

[Citrus]

It's a mystery. Nobody actually knows how big space is. They just like to think they do.

 

[Maze1125]

One thing that has always bothered me about the Hubble Deep Field image is if there are planets, stars, quasars, nebulae, galaxies, and other random outer space stuffs, then wouldn't most of that stuff be blocking out anything behind it, within the telescopes field of view? How, with our billions of stars in our galaxy, can we see beyond them to other galaxies? How do we get images like these?

The reason is because although they is a lot of stuff out in space there is a lot lot more "nothing".

If they are able to look back in time, then why can't they point the lens the opposite and see the future? Silly question, but really, why don't they ever look to the other direction opposite the center of the Universe?

The reason we can look back in time is because it takes light time to travel a distance.
If the light started out 1000 light-years away then, when we see that light, we're seeing something that happened 1000 years ago. If we look at something 10 billion light-years away then we're seeing something that happened 10 billion years ago (actually, the expansion of the universe messes the numbers up a bit, but the concept is the same.)

It doesn't matter which direction we look in, the light had to travel to reach us, and so every direction looks out towards earlier in the universe's life.

I mean, they say that we are near the edge of the universe, or at least on one of its outer arms, so what lies in that direction?

We're in one of the outer arms of our galaxy, not the universe.

 

[Twilight_guy]

Empty space is infinite (don't try to think why just know that you could walk forward for all eternity and never get to an end) but the universe as we know it is made up of stuff that is traveling outward and filling a portion of space.

 

[Julianking93]

What's at the edge? Is it just blackness? Would it just be like a wall that you can't pass through? Would I become a Reaver like in Firefly if I went to the edge?

"The Edge" referred to in Firefly was in fact only the edge of a solar-system, not the universe.

From the sounds of it, you haven't watched the film Serenity which, if you didn't know, is a continuation of the series.

Serenity is one of my favorite movies, I was just making a reference for entertainment purposes, I don't really think you can turn into a Reaver.

 

[Amondren]

I'm not a genus or anything but i think that it is I've also wondered something though we look at the galaxy like a sea chart whats bellow earth or above?

 

[Maze1125]

I'm not a genus or anything but i think that it is I've also wondered something though we look at the galaxy like a sea chart whats bellow earth or above?

That's just how it's portrayed so it can be easy for a layman to view.
Astronomers make sure to look in all directions, and generally it's just more of the same.

 

[Darzen]

well think about this for 1 second.since space is technicly a void.so we should be able to se the other side.but we see darkness thus the universe MUST end or the darkness wouldn't beable to stop at some thing thus the universe is not infinite but just finite or REALLY incomprehensable big.if it was infinite it wouldn't expand because once it's infinite it can't get bigger or it's finite(somewhere in there my statement makes logical sense)

 

[Maze1125]

well think about this for 1 second.since space is technicly a void.so we should be able to se the other side.but we see darkness thus the universe MUST end or the darkness wouldn't beable to stop at some thing thus the universe is not infinite but just finite or REALLY incomprehensable big.if it was infinite it wouldn't expand because once it's infinite it can't get bigger or it's finite(somewhere in there my statement makes logical sense)

You might want to go back and read some of my earlier posts in this thread. Such as this [http://www.escapistmagazine.com/forums/read/18.153094?page=3#3670413] one.

 

[FoolKiller]

Only the universe is infinite.