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Do You Believe There is Intelligent Life Beyond Earth?

  1. Dec 4, 2003 #1
    Drake's Equation is used to show that chances are that intelligent life evolved in other parts of the universe.

    Then I consider the possibility of Superstring Theory: alternative universes/dimensions where we would be completely oblivious to any intelligent life there.

    And consider our limited intelligence: we may not have the cognitive abilities to see what is really out there, similar to how lower animals cannot know what humans know.

    Reputable news sources, such as the History Channel, document many UFOs which to date have not been identified.

    Stories about actual contact with ETs.

    Paranormality/UFO/ET sources:
    http://www.rense.com/general41/dayfo.htm [Broken]


    Niels Bohr
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  2. jcsd
  3. Dec 4, 2003 #2
    Some "UFO Experts" speculate that some UFOs are actually time machines from the future of Earth. I of course remain agnostic to anything dealing with the paranormality.

    Niels Bohr
  4. Dec 4, 2003 #3


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    However, none of the links (edit - actually, thats only ONE source) you provided have anything to do with intelligent life elsewhere in the universe. They are not grounded in reality.

    There is a reason UFO and ghost sites are often found together - both are part of the same grab-bag of pseudoscientific nonsense.
  5. Dec 4, 2003 #4
    Beyond Earth, Hell I'm still looking for it here.
  6. Dec 5, 2003 #5
    My sources don't claim to be scientific, they are just summaries of what people claim to have witnessed or photographed. You are guilty of Straw Man.


    Niels Bohr
  7. Dec 5, 2003 #6
    whenever i play around with drake's equation, i obtain a very low prob of intelligent life

    one observation i can't dismiss is given the sheer abundance and variety of life on earth, only one species is intelligent/self aware/etc. certainly on earth, evolution favors other avenues of survival; is it not unreasonable to assume the bias toward unintelligent life applies universally?
  8. Dec 5, 2003 #7
    that because none of the numbers and probabilityes involved are exactly known...
  9. Dec 5, 2003 #8
    whether are not the inputs are "exactly known" is irrelevant; of course they are educated (hopefully) guesses. the point is whenever i input what i think is a reasonable range of assumptions spanning several orders of magnitude, i get an end result that is not optimistic.
  10. Dec 5, 2003 #9
    http://www.seti-inst.edu/science/drake-bg.html [Broken]

    would you mind showing us some values and justifing them (some links would be appreciated here)???
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  11. Dec 5, 2003 #10
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  12. Dec 6, 2003 #11


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    Straw man? You provided the source without making a specific claim of your own leaving me to infer what your point was. Regardless, I must ask then what the point was in posting that site?
  13. Jan 3, 2004 #12
    Drake Equation

    Is the Drake equation all inclusive? Could there be other factors involved in estimating the number of civilizations in our

    galaxy that is not taken into consideration in the Drake equation? Could any of the components that is used in the Drake

    Equation be superfluous information? Any additional or any missing information could dramatically affect the intended

    result. I'm not trying to intentionally debunk the accuracy of the Drake equation as it seems to be a well formulated and

    well thought out equation, I am merely asking the question: Could there be more to it? Here are some thoughts to consider.

    The following information has been taken from http://www.seti-inst.edu/seti/seti_science/drake_equation.html [Broken] .
    My comments will be placed with parenthesis().

    The Drake Equation: N = R* • fp • ne • fl • fi • fc • L

    N = The number of civilizations in The Milky Way Galaxy whose electromagnetic emissions are detectable.
    (This number would not include civilizations whose emissions cannot be detected - assuming the technology that has

    been used there actually gives off emissions into deep space)

    R* =The rate of formation of stars suitable for the development of intelligent life.
    (This would only include star systems we feel are suitable. Is it possible that an intelligent civilization does
    not need to meet our requirements of suitability to prosper)

    fp = The fraction of those stars with planetary systems.
    (Justifibly, we assume that these civilizations currently or at one time occupied a planetary system. Could a

    civilization out of our galaxy now occupy something other than a planetary system? Could the planetary system no

    longer exist and the civilization now lives on an artifical device?)

    ne = The number of planets, per solar system, with an environment suitable for life.
    (Simliar to the thought above)

    fl = The fraction of suitable planets on which life actually appears.
    (We gauge the suitability of a planet relative to what we require. Could an alien civilization live in a place we

    deem inhabitable?)

    fi = The fraction of life bearing planets on which intelligent life emerges. For more information, please visit Dr. William

    Calvin's "The Drake Equation's fi"
    (So far, our only experience of intelligent life emerging from a life bearing planet is Earth; therefore, this number

    is currently at 100%. We have no other basis to the estimate the probability that nonintelligent life gives
    rise to intelligent life.)

    fc = The fraction of civilizations that develop a technology that releases detectable signs of their existence into space.
    (Could they develop technology foreign to us? Could they develop technology that does not release emissions into
    deep space?)

    L = The length of time such civilizations release detectable signals into space.
    (This uses the length of time that alien civilizations acutally release detectable signals. Should it also be
    relative to the length of time we are actually capable of detecting them?)

    Last edited by a moderator: May 1, 2017
  14. Jan 3, 2004 #13

    Ivan Seeking

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    This is one of the few points about which I have high confidence: Intelligent life does exist elsewhere beyond any reasonable doubt. I think the only real question is how common intelligent life may be.

    If we didn't exist, my opinion on this matter would be much more tentative. :wink:
  15. Jan 4, 2004 #14
    I'm with you Ivan, I have no doubts that intelligent life exists elsewhere. I just feel that someone making a claim that it is improbable that life exists elsewhere based merely on the computation of the Drake equation is guilty of ignorance. As I said early, the equation seems to be well thought out, but maybe not thought out enough. I feel that there are far too many variables to take into consideration while estimating the probability of intelligent life. Right now, we just don't have enough information to gauge the extent of intelligent life.

  16. Jan 4, 2004 #15

    Ivan Seeking

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    Not only do most interprations of the Drake equation that I've seen suggest a high probability for intelligent life, but the Drake eqn only addresses this galaxy. How many galaxies are there?

    The question was beyond earth, not just in this galaxy.

    EDIT: by the way, welcome to PF jgravatt! :smile:
    Last edited: Jan 4, 2004
  17. Jan 4, 2004 #16


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    Intelligent life does exist elsewhere beyond any reasonable doubt.

    Considering that evolution does not demand intelligence, there is most certainly reasonable doubt. Your assertion is most likely based on what you want to believe.
  18. Jan 4, 2004 #17

    Ivan Seeking

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    So far, the evidence shows that given enough time, the chance for intelligence where we find life is 1.

    Personal attacks will not be tolerated. That's your second warning. Stick to the facts and stop the pseudo-psychological analyses.
  19. Jan 6, 2004 #18
    How does one define "intelligent"? Isn't it relative?

    Also, what makes you think that there is only one self-aware species on Earth?
  20. Jan 6, 2004 #19
    The Drake Equation: N = R* • fp • ne • fl • fi • fc • L


    R* = assumption.
    fp = assumption.
    ne = assumption.
    fl = assumption.
    fi = assumption.
    fc = assumption.
    L = assumption.

    N = the product of assumptions.

    Now apart from that Drake rubbish, let's consider a few facts.

    1) We know that the materials required for life exists beyond our planet. In fact, they even exist in deep space: http://www-691.gsfc.nasa.gov/cosmic.ice.lab/interste.htm What we also know is that those materials, and others, are more common on planetary bodies than in deep space. Therefore, the materials required for life are common on other worlds.

    2) We know that when you get a whole planet full of those materials, and stimulate them over a very long time with heat and pressure changes, different chemical combinations, tidal and weather influences, and more, eventually you get a certain combination called "life". We know this because it happened here.

    3) The only difference between the raw materials and life is time under stimulation. We know this because it happened here.

    4) The only difference between life and intelligent life is time. We know this because it happened here.

    You might now say "Just beacuse it happened here, that doesn't mean it can happen elsewhere".

    However, the fact is the physical laws remain the same everywhere. If it can happen here, it can happen elsewhere. That does not necessarily mean that it has happened elsewhere though. But consider the odds, given the size of the universe, the time it has existed, the amount of raw material under all sorts of stimulation out there.

    The Drake Equation is crap.

    A far larger problem is the Fermi Paradox.
    Last edited: Jan 6, 2004
  21. Jan 6, 2004 #20
    Now, there is one way around the Fermi Paradox which, to me, makes sense.

    We used to think that for life to work, we needed a fire at night to keep the wolves and such away. Now we don't need those fires.

    We used to think that we each needed so much land to support ourselves. Now we live in cities, with a few square metres each, while a few others out on farms send in food.

    We used to think it was kill humans to travel faster than 26 miles per hour. This idea was very swiftly disproven.

    At this moment, some few of us are aware that our use of energy is vastly inefficient and we simply pump out loads of wasted power into space. As we develop further, I suggest, we will learn to conserve energy, use it more efficiently, and not pump out excess power.

    We still have things to learn.

    But one thing is obvious, we will have to eventually stop pumping out wasted power. Technology attempts to become more efficient. Any advanced civilsation out there (if we take our own progress as an example), will be broadcasting excess power as we do for maybe fifty years, maybe a few centuries, but will eventually cease such wastefulness. Thus the reason we don't have a constant bombardment of signals from every direction. Thus the Fermi Paradox isn't really such a big deal.
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