It is my understanding that the big bang is not a theory of the origins of the energy of the universe, but is a theory of the origin of the structure of the universe (ie, it's early evolution). Also, I understand that it is a common misconception that the big bang is a theory of the absolute origin of the universe in this sense. Is that correct? What are some papers (eg. classic original research and/or more recent review journal papers) which deal specifically with the problem of identifying how far back big bang/inflationary theory can go? I've read Guth (1981), but I'd like something that discusses this problem more specifically. In addition, are there any classical papers which discuss hypotheses on the origins of the energy of the universe and how this relates (or does not relate) to the early development theories? Thanks!