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Hydrogen and the early universe

  1. Feb 4, 2010 #1
    Hey all,

    I was reading some stuff on-line, when I saw a post by someone that said:

    Hydrogen, a colourless, odourless gas, which left long enough will turn into people.

    Someone replied:

    Negative. An abundance of primordial helium is also required otherwise fusion in stars proceed too quickly to allow enough time for life to form.

    What are your thoughts on the original post and the reply. Is it not the case that Hydrogen will eventually make Helium and thus the statement is essentially true?

    Credible references (for my own sake and further reading) would be helpful too :)
    Last edited: Feb 4, 2010
  2. jcsd
  3. Feb 4, 2010 #2


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    Nice quote! I found it here about half way down the page:
    Hydrogen is a colourless, odourless gas which, given enough time, turns into people.
    — Henry Hiebert

    There are a bunch of good quotes on that page. To find the hydrogen one scroll down right about half way and then go about 10 more quotes down from that. It comes soon after the one from Captain Kirk of the Starship Enterprise:

    "Very funny, Scotty. Now beam me down my clothes."

    I think if you could magically restart the universe after somehow filtering out all the helium (but everything else the same) then it would still work. Because the first generation of stars would form a bunch of elements including helium and blow them out. And then you would have a mix of elements in the star-forming regions.

    I'm not especially sure about this, I've never seen it discussed. It seems kind of unphysical to imagine not having a bunch of primordial helium because (I assume you are not changing the relative strengths of fundamental forces, everything stays the same) given that the helium nucleus is so stable it is inevitable that a lot of it would form at the same time as hydrogen. So it is kind of artificial to imagine somehow filtering it out before you start the process of star-formation.

    But if you imagine monkeying with the fundamental forces so helium is no longer so stable then it is a whole new ball-game.

    I think it is a great quote, and contains an essential truth in a neat epigram package.
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