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Why all matter in the universe is scattered in such a way that it forms a spiderweb-like gigantic structure (superclusters) instead of being nicely scattered uniformly throughout the universe? Is this a direct consequence of dark matter/dark energy?
Starting with rather small quantum fluctuations (the fluctuations we now see in the varying density of the cosmic microwave background), gravity tends to make the lumpiness grow. Since most of the matter involved is 'dark', dark matter does play a major role.
Here is a nice web site showing how these fluctuations can grow into the structures we see today
(published on 09/29/09)
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