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Chalnoth
#4
Jan20-12, 12:46 AM
Sci Advisor
P: 4,805
Earth at the center of the Universe

Quote Quote by ugalpha View Post
So i read the answer of Marcus in the thread "Where is the Center of the Universe" where there was a brief mention of the "Un-Copernican" view of the Cosmos. Now i do not think that we are at the center of the Universe but this got me thinking.

"IF" the homogeneity of the Cosmos really was only the consequence of us being in the center of the Universe, How far away from our planet would we have to observe the universe to start seeing the heterogeneity of the Cosmos?

10,100,1000 billion miles?
I think you're mixing up terms. Homogeneity means the same everywhere. So it is directly contrary to the notion of us being the center.

You probably mean isotropy, which means the same in every direction. If the universe is isotropic but not homogeneous as viewed by us, then this means moving some distance away it would cease to look isotropic. Exactly how far we'd have to move, then, depends upon how things change as we move away from the Earth. But at the very least we'd have to move far beyond our own galaxy, which is around 100,000 light years across (As in close to a billion billion miles). We'd be talking millions of light years at least, perhaps hundreds of millions of light years, in order to see any difference.