Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: C-Jackson on 16/07/2012 14:09:16
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A question I have long pondered: best estimates of the age of the universe (from globular cluster data and inverse of the Hubble Constant) are from 14 to 18 billion years (by). Distance to some of the most distant observable objects (quasars) is upwards of 12 billion light years. First of all, this distance is not the current position of said quasar, but it's distance 12 billion years ago. So, this quasar was 12 billion light years away from our current position, 12 billion years ago. How does one account for the disparity in distances versus age of the universe. Even if both the earth and the quasar were moving in opposite directions from the point source of the big bang, they both would have to be moving FTL to reach the separated distances in the allotted time (which would, at a maximum, be 6 billion years)
I have heard the theory of "Phase Shift" of the universe during early expansion, which would account for some of this distance, but I'm still a little baffled...
Please use terms a biologist/SF writer can understand to explain this to me... Thanks!
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You should give us some references/links to check it up please. The light from something takes time to travel and if it has taken a million years to reach our eye then what we see is a description of something one million years ago. In that million years the object sending the light must have moved, presumably, but how fast?
The universe is isotropic and homogeneous, looking the same in any direction. It doesn't matter where you are when looking out on the universe. The Big Bang was a phenomena having no 'center', instead it was 'everywhere' and as the 'space' inflated particles came to be all over it. And in the end, we don't know how big the universe is, we can only measure what we observe. And that way we can find a age for it, but for the size of it?
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One more thing, it may be that it is 'seamlessly connected' so that you not knowing, believing yourself to travel in a straight line still will find yourself doing a 'round trip'. And so the universe become infinitively finite :) while constantly presenting you the same isotropy and homogeneous appearance.
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Thanks for the reply yor_on. Kind of what I thought... the "phase shift" after the big bang seems to have taken place at a point where the universe was already about the size it is today... At least that seems to be the current theory. Here's a link to a science blogger that does a good explanation: http://scienceblogs.com/startswithabang/2009/07/31/the-size-of-the-universe-a-har/