Alan Guth PROBLEM SET 5
نویسنده
چکیده
The formula for the entropy density of black-body radiation is given in Lecture Notes 7. The derivation of this formula has been left to the statistical mechanics course that you either have taken or hopefully will take. For our purposes, the important point is that the early universe remains very close to thermal equilibrium, and therefore entropy is conserved. The conservation of entropy applies even during periods when particles, such as electron-positron pairs, are “freezing out” of the thermal equilibrium mix. Since total entropy is conserved, the entropy density falls off as 1/R(t).
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Alan Guth REVIEW PROBLEMS FOR QUIZ 2 QUIZ
COVERAGE: Lecture Notes 6; Problem Set 3; Ryden, Chapters 4 and 5. One of the problems on the quiz will be taken verbatim (or at least almost verbatim) from either the homework assignments, or from the starred problems from this set of Review Problems. The starred problems are the ones that I recommend that you review most carefully: Problems 1, 2, 4, 8, 10, and 11. There are no reading questio...
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