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Theoretical physicist says universe has radius=10cm

  1. Jul 26, 2011 #1
    Hello everyone.
    I was just reading Ian Stewart's "Concepts of Modern Mathematics". In the end of the first chapter he writes

    A certain theoretical physicist secured himself a mighty reputation on the basis of his deduction, on very general mathematical grounds, of a formula for the radius of the universe [...] It was several years before anybody had enough curiosity to substitute the numbers in it and work out the answer. Ten centimeters."

    This seems quite the fluke. Is this actually true? Can you tell me who this "certain theoretical physicist" is/was?

  2. jcsd
  3. Jul 26, 2011 #2


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    He should have asked for help from Physics Forums before going to press. It would have saved him a lot of embarrassment.
  4. Jul 26, 2011 #3


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    For very large definitions of "centimeter"
  5. Jul 27, 2011 #4
    Or very small definitions of universe :P
  6. Jul 28, 2011 #5


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    The author couldn't be bothered to actually give the name of this certain someone and the papers involved?
  7. Jul 28, 2011 #6
    Paradox. ?
  8. Jul 28, 2011 #7
    via mathematical approach* quite possible!
  9. Aug 7, 2011 #8
    No, they author didn't bother. That's why I posted this, I am curious about it.
  10. Aug 7, 2011 #9
    Thats why physics is awesome. There is obviously still stuff to work out!
  11. Sep 11, 2013 #10
  12. Sep 12, 2013 #11


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    Note that they are talking about the size of the observable universe right after inflation, not at the big bang.
  13. Sep 12, 2013 #12


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    As the book from which the 10cm quote came was published in 1975, I wouldn't take very seriously any envelope-pushing claims it makes.
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