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Papers (preferably classic) on Big Bang/Inflationary theory and/or origins of energy?

  1. Mar 13, 2012 #1
    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?

  2. jcsd
  3. Mar 13, 2012 #2
    Re: Papers (preferably classic) on Big Bang/Inflationary theory and/or origins of ene

    It is a matter of taste how one uses the term "big bang". Generally in the cosmologist circles it is taken to mean the hot dense state some time before nucleosynthesis/baryogenesis/whatever lowish energy scale epoch you are interested in talking about. So you would say that the standard cosmology timeline is inflation -> reheating -> big bang -> everything else.

    The thing about energy is that you don't need any to produce a universe, even as large as ours, as long as you have physics which can initiate inflation. After inflation has started, the total energy stored in the inflating field increases almost exponentially, and at the end of inflation, it is enough to produce all the particles we see around today.
  4. Mar 15, 2012 #3


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    Re: Papers (preferably classic) on Big Bang/Inflationary theory and/or origins of ene

    Unfortunately, the language here is sometimes confusing, because there are two different definitions here.

    1. The Big Bang Theory is exactly as you describe. It is a description of how our universe has changed over time. It does include a starting point, but because that starting point is a singularity, basically nobody believes that is a "real" event. People generally only trust the theory for later times, in particular where it has been tested in detail, and expect some other theory to describe what happened before.

    2. The big bang event is generally used to refer to whatever event started off our region of space-time, or alternatively to the extremely hot and dense state at the early universe. It is sometimes, confusingly, used to refer to the singularity that nobody believes exists. So in general, when somebody is talking about the big bang as an event, they mean a time in the very early universe, but the specific definition of precisely when can get a little bit fuzzy. However, all of the fuzzy definitions of the big bang event occur within a minuscule fraction of a second of one another, so that for most practical purposes they are the same.
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