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The First Three Minutes - Steven Weinberg

  1. May 20, 2012 #1
    Has anyone studied the book "The First Three Minutes" written by Steven Weinberg? In this book the author stated the early universe conditions as: "At about one hundredth second after the big bang, the temperature of the universe was about a hundred thousand million degrees Centigrade. As the explosion continued, the temperature dropped, reaching thirty thousand million Centigrade after about one-tenth of a second, ten thousand million after about one second and three thousand million degrees after about fourteen seconds".

    Can anyone tell me about a scientific book or paper where these data are written in a reliable format?
     
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  3. May 20, 2012 #2

    phinds

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    Since Weinberg is an authority on this, why not poke around on the internet to see if you can find papers by HIM?
     
  4. May 21, 2012 #3
    yes!! Thanks for the idea... but if you know where to look... tell me
     
  5. May 21, 2012 #4

    Chronos

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    Try arxiv.
     
  6. May 21, 2012 #5

    alt

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    He's an authority on this ? The OP's quote of the book says;

    As the explosion continued ..

    Yet we hear constantly that it was no explosion.
     
  7. May 21, 2012 #6
    I suspect there may have been sarcasm in Phinds's post.
     
  8. May 21, 2012 #7

    phinds

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    No sarcasm. Weinberg IS an authority on this. Unfortunately even good serious physicists such as he is DO use really sloppy language in their popular books.
     
  9. May 21, 2012 #8
    Guys... thanks a lot... but can you provide me some papers where I can find these exact data?
     
  10. May 21, 2012 #9

    phinds

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    reread post #4
     
  11. May 21, 2012 #10
    Thanks. Can you give me specific links? It will save a lot of my time.. moreover this is not my field...
     
  12. May 21, 2012 #11

    phinds

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    You may get lucky and someone here will know of something, or even less likely someone may be willing to do your research FOR you, but generally, folks here are expected to do their own work where they can, and you can do a search as easily as anyone else.
     
  13. May 21, 2012 #12

    Borek

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  14. May 21, 2012 #13

    alt

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    Thanks. Sloppy language can be a problem ..
     
  15. May 21, 2012 #14

    Bobbywhy

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    @Borek: Thank you for the link to arxiv! That is great fun.
     
  16. Jun 24, 2012 #15
    I happened to read bits of this book last night.

    I think it's more critical than sloppy language. I've only ready Chapt 2, Expansion of the Universe, but there are several issues.

    He states several times that the recession velocity of very distant galaxies must be corrected to avoid going above speed of light. We know that's wrong, distant galaxies can and do recede from us at speed greater than c. That's the whole point of the Hubble sphere. (I've since noted that this very book is listed in the references of the "Common misconceptions" paper by Davis & Lineweaver).

    What really bugged me is the conclusion of the chapter. It goes something like that (re-translated from French to English so not the original text) :

    « We don't think that this expansion is the effect of a particular repulsive cosmic force, but simply escape velocities acquired in a past explosion. These velocities decrease progressively under the influence of gravity (…) »

    :frown:
     
  17. Jun 24, 2012 #16
    Also, sometimes famous physicists will use language that in hindsight is considered non-optimal. One example of this is George Gamov's explanation of relativity as increasing mass, which has led to a lot of confusion and it's considered non-optimal today. The first edition was written in the late 1970's, and I think it's taken a while for people to get confused looks from people thinking about the big bang as an explosion to realize that it's not a good idea to call it an explosion.

    The other thing is that google has it's limitations. For one thing google doesn't classify things by level of difficulty, and it's difficult to get something that is between at the popular science level and things that are intended for graduate students. Weinberg has written several excellent graduate level textbooks, but that may not be what the OP is looking for.
     
    Last edited: Jun 24, 2012
  18. Jun 24, 2012 #17

    phinds

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    The original edition of this book was written in 1977. No, wait. Actually, it was PUBLISHED in 1977, so written even earlier. The accelerated expansion of the universe was not known at that time. Even the 2nd edition was published in 1993 and the accelerated expansion was STILL not known.

    SO ... you are complaining about the guy not knowing stuff that NOBODY knew?
     
  19. Jun 24, 2012 #18
    That's not the problem. What will happen is that even with decelerating universes you will have galaxies eventually go past the hubble horizon. v=Hr. You set v to c, and you'll get the radius at which galaxies are going away from you faster than light.

    Now, I think he was referring to special relativistic corrections and talking about galaxies that we are observing now, but it's still potentially misleading.
     
  20. Jun 24, 2012 #19

    phinds

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    Yes, clearly I didn't think it all the way through. Thanks for that correction. I was focusing on the age of the book more than the content being discussed ... big mistake.
     
  21. Jun 24, 2012 #20

    RUTA

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    The v = c sphere can reside inside the particle horizon, so we can see galaxies with v > c. That is the case in the most popular model, i.e., Einstein-deSitter.
     
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