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Life in Universe, statistical point of view

  1. Aug 8, 2008 #1

    I was having a discussion with a friend about the probability of life in the universe outside of earth.

    From what i know, there are 70 000 000 000 000 000 000 000 stars and god knows how many planets. Given the low probability of life spawning on a single planet but the huge amounts of planets that add up my opinion is that not the biggest surprise in the universe would be not to find life.

    By life we can think of basic life and intelligent life. Is it the generally accepted theory in accordance with my point of view or am i missing an important fact somewhere along the road?
  2. jcsd
  3. Aug 8, 2008 #2


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    A nice example here is the Drake equation. It shows how a simple argument can be used to support both claims (we are alone, and there are many other planets with life). In the link I gave you, you will find two reasonable sounding sets of parameters leading to completely different results, at the very bottom of the "Historical estimates of the parameters" section.
  4. Aug 8, 2008 #3
    Tank you very much. The drake equation seems to be focusing on the chances that we find an advanced enough form of life that is able to communicate.

    I think it is the most difficult and for sure the greatest achivement that could happen in mankind history.

    But beyond that, my view was that is it safe to assume that some kind of life, from simple forms to highly advanced forms, exist in the universe. Is that a view shared by most experts on that question?
  5. Aug 8, 2008 #4
    We spend many billions of dollars to find life elsewhere than Earth, so I think it is safe to assume that is the presumption "shared by most experts"....that it is out there and we expect to find it eventually.
  6. Aug 21, 2008 #5
    most people would like to think they are very special in the universe, so they would say NO

    we certainly are not the first in creation, so why would there not be others?
  7. Aug 22, 2008 #6
    Though this is slightly off-topic I find it interesting that the four most commonly used elements found in living things are also four of the most common reactive elements in the Universe.

    See http://en.wikipedia.org/wiki/CHON" [Broken]

    So I think there is definitely life out there too.
    Last edited by a moderator: May 3, 2017
  8. Aug 22, 2008 #7


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    I think that i sthe veiw "shared by most experts", but I think (and hope) that most of the scientific community is keeping an open mind and willing to except what the evidence says, rather than looking for the result they want. I myself am completely open on this one; I could believe the results either way.

    Many of the variables involved (the variables in the Drake Equation) are completely unknown. As far as I'm concerned the issue is 50/50; the answer is either "yes" or "no."
  9. Aug 26, 2008 #8
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