Quote:
Originally Posted by SingleDad
ok I'm over thinking,and haven't finished the show yet, but... why aren't the photons that where fired 13bil light-year, and traveled 78 bil light-years to get here... didn't it go past the speed of light to get here... ouch! stop it hurts!! =p
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This is how I understand it:
The photon has travelled 13.7 billion lightyears to get here, but the place the photon started from has since been carried away by the expanding universe, and is now 78 billion lightyears away.
It also means when the photon started out, that place was a lot
closer than 13.7 billion lightyears to this place - that original distance has expanded to 13.7 billion lightyears in the meanwhile. (And, of course, the Earth wasn't even here then, just some hydrogen gas floating about that would eventually become the Milky Way, Earth, people... just in time for that photon to hit WMAP. Weird huh?)