Guth PROBLEM SET 10 ( The Last ! ) DUE
نویسنده
چکیده
The success of the big bang predictions for the abundances of the light elements suggests that the universe was already in thermal equilibrium at one second after the big bang. At this time, the region that later evolves to become the observed universe was, in the context of the conventional (non-inflationary) cosmological model, many horizon distances across. Try to estimate how many. You may assume that the universe is flat, that it was radiation-dominated for t < ∼ 50,000 yr, and for this crude estimate you can also assume that it has been matter-dominated for all t > ∼ 50,000 yr, and that a(t)T (t) ≈ const for the whole period from 1 second to the present.
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