How can astronomers see light from shortly after the big bang? How did we get "here" before the light that emanated from our "creation"?
Answer
You ask:
How can astronomers see light from shortly after the big bang? How did we get "here" before the light that emanated from our "creation"?
The very idea of "Big Bang" assumes General Relativity holds.
An analogue of this big bang can be a balloon that starts from a point and starts expanding. Our three space dimension universe has as analogue the two dimensional surface of this balloon. Everything we observe, the light going from point to point on the balloon is on that surface . The inside of the balloon is not a space where matter or photons propagate. Everything happens at the expanding surface.
Thus the light the astronomers see from the Big Bang, the cosmic microwave background radiation is the light coming from everywhere on our point on this surface. We hypothesize a time 0 for light coming to us because we see how cold the photons are, and calculate the red shift from the initial hot production of all those photons. But they are coming from everywhere ( the balloon analogue).
It is very anthropic in a sense to claim that we each of us are the center from where the Big Bang started :).
No comments:
Post a Comment