by Empeda » Wed Jul 20, 2005 3:57 pm
The distance we can see is limited because of the big bang:
According to current theory, up to 300,000 years after the big bang, the universe was opaque - that is, a photon of light could not travel very far without being scatter, so therefore the universe wasn't 'see-through'.
A process called recombination then occurred (which on a basic level involved the formation of atoms and molecules) which made the universe transparent, meaning that the average distance that a photon of light would travel before being scatterred was greater than the 'diameter' of the universe.
The consequence of this is if the universe is about 13 billion years old - we can only see a far back as 13billion-300,000 light years, and before that the universe was opaque. We do see the 'echo' of this early stage though in the form of the Comic Microwave Background.
I'll see if I can find a link to someone who can explain this 1000 times better than I can......
The distance we can see is limited because of the big bang:
According to current theory, up to 300,000 years after the big bang, the universe was opaque - that is, a photon of light could not travel very far without being scatter, so therefore the universe wasn't 'see-through'.
A process called recombination then occurred (which on a basic level involved the formation of atoms and molecules) which made the universe transparent, meaning that the average distance that a photon of light would travel before being scatterred was greater than the 'diameter' of the universe.
The consequence of this is if the universe is about 13 billion years old - we can only see a far back as 13billion-300,000 light years, and before that the universe was opaque. We do see the 'echo' of this early stage though in the form of the Comic Microwave Background.
I'll see if I can find a link to someone who can explain this 1000 times better than I can......