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Planck length

  1. Nov 20, 2005 #1
    Could someone give me a layman's definition of this unit? I've looked about on wikipedia and Google search results, but I'm still not clear on what this measurement actually is?

  2. jcsd
  3. Nov 20, 2005 #2
    planck length = sqrt[(G*h-bar)/c^3]=10^-35m
    G=gravtational constant
    h-bar=plancks constant over 2pi
    c= speed of light
    Plancks length combines all the constants of nature and gives kind of a length where quantum mechanics and general relitivity breaks down. it's also the hypothetical lenght of an average string in string theory
    Last edited: Nov 20, 2005
  4. Nov 20, 2005 #3
    you can also combine the constants of nature to give you planck energy and planck time
  5. Dec 3, 2005 #4
    it is the scale at which all the forces of nature are unified
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