Is the universe infinite?

[OneArmedScissor]

Ok... I just got into a long discussion with a friend of mine as to whether or not the universe is infinite or finite.

I said it was sort of a mixture of both. Like a sphere inside itself. Or something you see off in the distance, but no matter how fast you run or travel, you'll never get to it.

His argument was that the universe was infinite... That it goes forever with no ends, etc.

Basically, my whole point was that it was neither, but shared properties of each (infinite and finite). His whole argument was that, "since you can never get to the end of it, that means it's infinite."

Anyways, any inputs would be appreciated!

[infamous]

Originally Posted by OneArmedScissor

Ok... I just got into a long discussion with a friend of mine as to whether or not the universe is infinite or finite.

I said it was sort of a mixture of both. Like a sphere inside itself. Or something you see off in the distance, but no matter how fast you run or travel, you'll never get to it.

His argument was that the universe was infinite... That it goes forever with no ends, etc.

Basically, my whole point was that it was neither, but shared properties of each (infinite and finite). His whole argument was that, "since you can never get to the end of it, that means it's infinite."

Anyways, any inputs would be appreciated!

These questions may never be answered with any absolute precision but the standard model views our local universe as a finite sphere. Nevertheless, our local universe may be contained within a larger megauniverse which may be infinite in nature. Hopefully this defination does not confuse things for you.

[C1ay]

The Big Bang model of the universe is finite. I personally believe the big bang universe is just an event in an infinite universe. We'll likely never know the real answer.

[OneArmedScissor]

I understand all that completely. But what pissed me off more than just about anything through the whole argument, would be that he would make these ridiculous claims/speculations. Whenever I would ask him how he came up with this, and that there is no evidence to support these claims at all, etc., he would just be like "yeah but you can't prove me wrong because you don't know"............................................. ..........
I hate arguing with people like this. Why should it be my responsibility to prove you wrong when there is no evidence to support your claim in the first place? Most annoying thing ever.

[Harzburgite]

Originally Posted by OneArmedScissor

I hate arguing with people like this. Why should it be my responsibility to prove you wrong when there is no evidence to support your claim in the first place? Most annoying thing ever.

Unless you are practicing your debating skills the best policy is to avoid such people. There are plenty like that on forums such as this. (Remember to do as I say, not as I do )

[C1ay]

Originally Posted by OneArmedScissor

Why should it be my responsibility to prove you wrong when there is no evidence to support your claim in the first place? Most annoying thing ever.

It's not. It's the burden of the one making a claim to prove it. As the critic it is your responsibility to point out the holes in his proof once he provides one. It doersn't sound to me like you are arguing with a scientist.

[EWright]

Originally Posted by C1ay

The Big Bang model of the universe is finite. I personally believe the big bang universe is just an event in an infinite universe. We'll likely never know the real answer.

I'm sorry, but the Big Bang model does not predict a finite universe.

[C1ay]

Originally Posted by EWright

I'm sorry, but the Big Bang model does not predict a finite universe.

You are saying the big bang universe has no boundary?

[EWright]

Originally Posted by C1ay

You are saying the big bang universe has no boundary?

No, big bang cosmologists say the big bang universe has no boundry. Certainly you've heard the comparative metaphore of an ant walking on the 2 dimensional surface of an expanding balloon. In those two dimensions, the baloon has no boudries. This is then applied to the third dimension, when referring to the infinite properties of the universe. It is generally difficult for most people to understand or conceive of in three dimensions.

As for the shape of the universe: flat, spherical, or hyperbolic. It is generally believed to be flat and infinite. The shape of the universe will ultimately decide its fate -- whether it expands for ever (the leading theory due to dark energy and an increasing rate of expansion) or collapse (if gravity can overcome dark energy and draw all matter back into a singularity via a 'big crunch').

[C1ay]

Originally Posted by EWright

No, big bang cosmologists say the big bang universe has no boundry. Certainly you've heard the comparative metaphore of an ant walking on the 2 dimensional surface of an expanding balloon. In those two dimensions, the baloon has no boudries. This is then applied to the third dimension, when referring to the infinite properties of the universe. It is generally difficult for most people to understand or conceive of in three dimensions.

As for the shape of the universe: flat, spherical, or hyperbolic. It is generally believed to be flat and infinite. The shape of the universe will ultimately decide its fate -- whether it expands for ever (the leading theory due to dark energy and an increasing rate of expansion) or collapse (if gravity can overcome dark energy and draw all matter back into a singularity via a 'big crunch').

So you are saying that conclusions from WMAP suggesting the universe to be 156 billion light-years wide are incorrect? Do you also disagree with claims that the universe has a finite quantity of matter?