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Probability that an exact copy of something can exist in a very large universe

  1. Apr 10, 2012 #1
    I was watching a video about googolplex which can be found here:

    my question is: even if the "number of states" of all the particles of the volume a person takes up is 101070 and the universe was 1010100 meters, it would not mean that there must be an exact copy of that person (all the particles in the same state) somewhere in the universe. It seems more likely that there will be many more "exact copies" of clouds of hydrogen gas, and exact copies of small clouds of dust, but only a chance (relatively low for that matter) that there is another "exact copy" person.

    I may be wrong, I'm a little bit confused. Thanks for any help its much appreciated!
  2. jcsd
  3. Apr 10, 2012 #2


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    Yes, that't true. You can (all of those numbers are very rough estimates, of course) calculate the probability that a person's molecular structure is exactly reproduced but it will never be "certain". Also important is that those calculations are typically based on random combinations of molecules and the molecules in a person are certainly not random combinations.
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