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Hubble length

  1. Jul 17, 2008 #1
    I am presently reading a paper on Inflation. It uses the term Hubble length. Can someone provide the Hubble length in cm.
  2. jcsd
  3. Jul 17, 2008 #2


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    The Hubble time is about 14 billion years. That means the Hubble length is about 14 billion lightyears. 13.8 might be better.

    definitions: the hub time is 1/H0
    the hub length is c/H0

    just use google calculator. type this into the google search window verbatim
    71 km/s/megaparsec
    and press "search"

    you will get an inverse time in Hertz

    now type c divided by that, verbatim, in other words
    c/(71 km/s/megaparsec)
    and say search again

    you will get 1.3 x 1026 meters

    that is the hubble length in meters
    google calculator will just calculate it for you automatically and tell you that
    Last edited: Jul 17, 2008
  4. Jul 17, 2008 #3


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    Thus, it is probably silly to describe it in centimeters.
  5. Jul 17, 2008 #4
    Google calculator also does automatic unit conversion, you can say things like

    c/(71 km/s/megaparsec) in centimeters

    It is a great tool.
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