Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Intelligent Life

  1. Nov 19, 2007 #1
    A few questions that I've been thinking about in terms of intelligent life.

    What would be the best kind of signals to send into deep space if we wanted to announce the presence of intelligent life on Earth?

    What defines intelligence, anyways?

    Where would be the best place to beam whatever signals we send in order to allow for the greatest range?

    Thanks for all input.
  2. jcsd
  3. Nov 19, 2007 #2
    For the first question, I can't think of anything better to send then good ol' EM radiation in set mathimatical pulses repeating the first few steps of a fiminiachi sequence. Forgive the poor spelling.

    1-1-2-3-5-8-13 then repeat. Language is unique to groups, but mathimatics and logic are universal.

    As for what definies intelligence in the universal sense, I'm afriad I have no clue. What if there's intelligent sentient electro-maginetic wave patterns in the sun? How would we know?

    That's what makes it so exciting, what gaurentee do we have that we'll recognize it when we see it? What wonders could there be for the open mind to comprihend?

    Sorry, I'm waxing philosophical.

    As for where to broadcast, a tetrahedral pattern around the galaxy would be heard pretty well, the catch as always would be setting it up.
  4. Nov 19, 2007 #3


    User Avatar
    Science Advisor

    For SETI, the definition of "intelligent life" has always been, "aliens who have radios." This is their "working definition," and not very rigorous. They also concluded that EM was the obvious choice, and that the frequencies we call "radio" were best, because they're long enough to cut through most of the junk in between the stars.

    I personally think prime numbers would be a better message. The Fibinocci Sequence shows up so frequently in nature that it may actually be a naturally-occurring radio-wave phenomanon. I'd hate for our signal to replicate a naturally-occurring one.
  5. Nov 19, 2007 #4
    I personally vote for laser beams that could be used to signal things like pi. It would be hard to ignore a specific color of laser beam that tapped out the first ten or so digits of pi. That would be a signal that an evolved and intelligent species should recognize. Keep in mind that they will need to at least have reached a stage that is close to our level of technology to be able to "see" that signal.

    That's a very good question, and it's not easy to answer. I tend to think humans are pretty vain in their approach to what defines "intelligence". It seems to me that many forms of life, particularly mammals are highly intelligent creatures. Not many species however on a given planet will build mechanical tools in an effort to control their environment the way that humans do. We might define "intelligence" as any species that is space fairing. Even that is an arbitrary definition, and space travel was beyond human capacity until quite recently. We're humans less intelligent 4000 years ago, or just less evolved in terms of technology? Even though we can get ourselves into space today, we are still limited to traveling within our own solar system because of the nature of our current technology. Since we can't get out of our own solar system, we are only "moderately intelligent". :)

    We should probably start in our own galaxy and pick stars that are closest to us. Due to the distances involved, it's highly unlikely that a physical being with a limited lifespan could traverse intergalactic distances. It would also take an extremely long time to "beam a signal" to a distant galaxy and to have anyone who might wish to respond to send a signal back to us. We should probably begin our search for other space fairing species with the closest solar systems to Earth, and methodically hit the closest stars first.
  6. Nov 21, 2007 #5
    I think to get an accurate answer to that question, you would have to compare it to something else. Or have a base requirement or measurement that you can scale it up to.
  7. Nov 21, 2007 #6
    Sometimes I wonder what planet you guys come from. Tell me honestly if anyone would actually disclose whether intelligent life had been detected. Think of the ramifications of the disclosure and, depending on how close to home they were found, it would cause chaos.

    SETI will only ever be able to say "we probably", or "maybe" etc etc leaving a lot of room for possibilities and explanations by governments, religions, and similar authorities. SETI is an attempt to make it look like we are looking. If anyone really thought about what would happen if they found, they would save the money they used to set it up.

    Consider how far we have come in the last 50-100 years and think of how advanced any other civilisation that we find is likely to be. Anyone out there is probably light-years more advanced than we are, and by that time they will not need to answer us by old-fashioned radio waves, they will just appear here and say "Hi". By the time you are that advanced, distances are no problem. I hope they are friendly too.
  8. Nov 24, 2007 #7


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Or not ... surely it's just as much a stretch to think that c is, truly, an absolute speed limit as it is to think that it isn't?

    I mean, how to tell?
    If 'they' are to us, as we are to {insert your favourite here, say Sus scrota} in the 'intelligence' department, then 'friendly' may not be quite the right word to use ...
  9. Nov 24, 2007 #8


    User Avatar
    Science Advisor

    There is no way the existance of ETI could be kept secret. Remember LGM1967? If a signal is found, it will be circulated around the world and talked about in the news before anyone even knows for sure if it is a signal. All the people volunteering their home computers to SETI@home would have the signal in their PC's.
  10. Nov 24, 2007 #9


    User Avatar

    Staff: Mentor

    Why would it cause chaos? By now, a pretty high fraction of the population thinks we may not be alone and many more are open to the idea even if they don't have a well-formed opinion on it.
    Well, if they got the evidence they were hoping for, SETI would be able to convince basically anyone who wasn't a schetzophrenic. There will always be a small fringe who thinks NASA faked the moon landings too, but conspiracy theory aside, a TV transmission (for example) from another world would be pretty convincing evidence.
  11. Nov 24, 2007 #10
    You make a good point on the part that if they're light years more advanced than us that distances are no problem.

    You really got me thinking...
    If a galaxy is light years ahead of us, are they really more advanced? Can they be light years behind also? Then would we be more advanced than them?
  12. Nov 24, 2007 #11


    User Avatar
    Science Advisor
    Gold Member

    A more advanced race would think hard before responding. After all, what is in it for them? Will they benefit from our ignorance more than we would from their enlightenment? Knowing how we are, they would probably decline the invitation.
  13. Nov 25, 2007 #12


    User Avatar
    Gold Member

    I believe that intelligence is directly correlated with a demonstrable ability to problem-solve - to adapt - to find solutions to problems not previously encountered.
    Last edited: Nov 25, 2007
  14. Nov 25, 2007 #13


    User Avatar
    Gold Member

    Well, we're not exactly far enough ahead for anything to be very far behind us.

    We've only been sapient for tens of thousands of years. We've only had technology for hundreds. We've only had the ability to affect anything outside our own planet for seventy.
  15. Nov 25, 2007 #14
    Well, it's hard to know if it's much of a problem. The distances between galaxies is huge, so intergalactic travel may be out of the question, even for very advanced physical species. Anything we might find inside our own galaxy is likely to already know that we exist, and they probably don't think of us as all that "intelligent", especially considering the global political conditions on Earth today. I suspect if they're smart, they'll hide. :)
  16. Nov 25, 2007 #15
    M Mozina said

    Unbeknownst to us, we are probably under quarantine right now, as a noxious planetary infection.

    Anyway, getting back to the original post, I think in addition to sending mathematical constants like pi or e, prime numbers, or fibonacci series, we could send music or art images or even text, if we could figure out a way to send a rosetta stone to decode this stuff. Or, more simply, just a repeated morse code: S - O - S .

    Question: Assume we send pi. In what base would we send it? If it were base 2 binary, and we received it, would we recognize it?
    Last edited: Nov 25, 2007
  17. Nov 26, 2007 #16
    Maybe they will have to respond in order to learn we are ignorant :smile:
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook