Age versus Size of Universe
If we are able to see galaxies that are 12 billion light years
away in both directions, how long did it take for those objects to get
that far apart from each other? Surely they cannot be moving away from
each other (or us) at the speed of light! Even if the separating speed
averaged one-half the speed of light, they must have taken 24 billion
years just to get to where they were, as we see them, 12 billion years
ago. Now add the 12 billion years that the light took to get to us so we
can observe them, and that makes at least 36 billion years, doesn't it?
I do not think it works that way. We are not in the middle of the Universe,
and the farthest galaxies measure in at about 13 billion light years.
I think you may be working on the misinterpretation of the concept of
the Big Bang and the corollary idea that the universe is expanding with
the idea that galaxies that are currently moving away from us have been
doing so since the Big Bang.
Imagine for the moment that the Big Bang created a universe that is
practically as large as it is now in the first few seconds of the Big
Bang event. Then imagine that the universe continued to expand -although
nowhere near as fast as it did in the first few seconds of the Big Bang
event - due either to the residual effect of the Big Bang or, as some
are beginning to theorize, the natural action of vacuum, then any galaxy
that is formed after the few seconds of universe development will be
formed at a certain distance away from us and will move away from us at
the rate relative to its distance from us and as a function of the
current rate of expansion of the universe.
Greg (Roberto Gregorius)
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Update: June 2012