Quote:
On 2003-02-16 08:38, michael cyrek wrote:
"A question for Chip or even JS for that matter...What if you increased that hypothetical distance to 13 billion years, would you see any evolution? If you do then you are close to the center of the BB while instantaneously, the BB is still there with all its galaxies and etc. Therefore, the BB has (one)_a center."
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JS makes the point succinctly. Even if someone could jump away 13 billion light years at once, they'd still observe a universe expanding everywhere away from them, with the most distant red-shifted objects, as well as the CMB appearing as they do from earth. Remember that even if you're on earth or a distant world, you're seeing remote objects
as they looked 13 billion years ago. (
In the past.)
The BB is not like a conventional explosion, with matter flying out in all directions from a center, filling a pre-existing space. The BB
is the
beginning of space, time, and matter.
One could think of the universe as not having a "center." If you want a center, you could perhaps think of the "center" of the universe as being
everywhere. You could also think of it as being outside the observable universe - in the past. Notice that the CMB is closer to the
beginning than we are, and is everywhere in the sky, whereas more concentrated objects (like galaxies) are located in specific locations in the sky.
Dark energy seems to make up most of the universe and is apparently fundamental to the expansion and acceleration. Understanding dark matter and dark energy are fields that will be keeping astronomers and physicists busy for a long time to come.