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odysseus0101
2002-Jan-09, 06:20 AM
I'm sure that contemporary theories of the formation of the universe (at least of the matter of the universe...but that is an entirely different topic [and one with which, if I may say, astronomers are not enitrely equipped to deal]) can account for exactly why the matter radiating out from the point of the Big Bang coalesed into stars where it did, but I've never heard it. Here's what I'm thinking: All the matter in the universe is condensed into one superdense mass. This mass explodes, and all its matter radiates away from it. It seems that this matter would be radiating with perfect uniformity, as a rapidly expanding sphere, because there would be no external gravitation to warp the explosion into a non-uniform consistency. If this matter is exploding outward from a central point with perfect uniformity, what would cause any particular point within that explosion to condense into a larger object?

Jim
2002-Jan-09, 12:12 PM
In a word, inflation.

Early (like 10<sup>-35</sup> seconds after the BB) in the growth of the Universe, there was a "phase change" or "symmetry break" that released a lot of energy. This caused a very rapid expansion which led to "lumpiness" in the Universe. Gravity then did the rest.

A fuller explanation can be found at:

http://archive.ncsa.uiuc.edu/Cyberia/Cosmos/SeedsStructure.html

ToSeek
2002-Jan-09, 01:47 PM
On 2002-01-09 01:20, odysseus0101 wrote:
If this matter is exploding outward from a central point with perfect uniformity, what would cause any particular point within that explosion to condense into a larger object?


The current theory seems to be that the structure of the early universe was significantly influenced by sound waves, and it's the structure of the sound waves that's being detected in the minute variations in the CMB:

http://www.spaceflightnow.com/news/n0105/02bigbang/