What is the connection between Olber's paradox and the age of the universe?

[TheAlkemist]

I just watched this http://www.youtube.com/watch?v=TFwtJC9_dXs" that said it's because the universe has a finite existence and the light from most of the stars hasn't reached us yet and this would be an argument against an infinitely old universe. Is this correct?

 

[Pengwuino]

No. It's simply because the sun is on the other side of the Earth.

 

[Akcope]

No. It's simply because the sun is on the other side of the Earth.

Exactly. It wouldn't be so dark at all if your eyes could detect visible light better.

But seems like a misunderstanding, perhaps a rephrase and better explanation of your question is in order.

 

[Doc Al]

I just watched this http://www.youtube.com/watch?v=TFwtJC9_dXs" that said it's because the universe has a finite existence and the light from most of the stars hasn't reached us yet and this would be an argument against an infinitely old universe. Is this correct?

I haven't watched that clip, but I think that's essentially the correct answer to what was called Olber's paradox.

 

[TheAlkemist]

I haven't watched that clip, but I think that's essentially the correct answer to what was called Olber's paradox.

Yes, that's what the explanation was in the clip. But is it in conflict with an infinite/eternal universe?

 

[Doc Al]

But is it in conflict with an infinite/eternal universe?

I'd say so. Perhaps a cosmologist will chime in with more details.

 

[Chalnoth]

I just watched this http://www.youtube.com/watch?v=TFwtJC9_dXs" that said it's because the universe has a finite existence and the light from most of the stars hasn't reached us yet and this would be an argument against an infinitely old universe. Is this correct?

This particular answer to the paradox requires the assumption of a static universe. If we have an expanding universe, light from distant stars is redshifted, and Olber's paradox never occurs. It is the expansion, then, that solves the problem.

Now, for entirely different reasons, the expansion of the universe requires an expanding universe to have a finite age, because if you extrapolate back in time too far, you end up with a singularity. Nobody expects this singularity to be real, but somewhere between here and the singularity must be some sort of physical process (currently unknown) that generates a region of expanding space-time.