Aliens - Are they out there?

  1. I've asked this question to a lot of people and a good majority of them said no, aliens do not exist. I just don't understand their logic in thinking that. To me I think there's a 100% chance that inteligent life exists out there. Life on our planet isn't so special in my eyes, to me it seems life in the universe would be just as common. Our planet is crawling with creatures of all shapes and sizes, some more inteligent than others. If a planet out there had the same, or similar conditions, life from here could live there perfectly. I mean, there's probably billions of lives being born, living and dieing every day on this planet, human or not. Is that really not a mirical that could exist some where else in the universe?

    We have 2000 years of recorded history, which is a hell of a long time. With the size of the universe and the amount of time it's been alive there could be species out there who have 4000 years of records, maybe even 5000 or 10,000, who knows. They could be in a multi-populated system, even in a multi-populated galaxy, all of which we are completely oblivious to.

    I don't understand why people think that way, but they do... Maybe someone could shed some light...
  2. jcsd
  3. D H

    Staff: Mentor

    The Hitch Hiker's Guide to the Galaxy is a wholly remarkable book. The introduction begins like this:

    "Space," it says, "is big. Really big. You just won't believe how vastly hugely mindboggingly big it is. I mean you may think it's a long way down the road to the chemist, but that's just peanuts to space. Listen ..." and so on.

    We might as well be alone in the universe if the closest intelligent life form is two or three galaxies away from us. There is good reason to believe that intelligent life is not widespread at all. See this thread.
  4. chroot

    chroot 10,351
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    The questions Does alien life exist? and Have we or will ever communicate with or be visited by alien life? are very distinct.

    I personally believe that life is not unique to the Earth, and other planets almost assuredly have something we would classify as "life," even if it's near the boundary between what we'd simply call "chemistry." Quite a lot of "biochemistry" can happen in a test tube without really being connected to anything we'd call "life."

    Despite believing that alien life exists, I believe that we will never communicate with it or be visited by it. We've seen on earth that evolution favors simplicity, and the majority of the earth's biomass is bacteria and lower forms of life. I suspect that life elsewhere would go a similar route, and intelligent life is probably quite rare.

    You might want to fill in Drake's equation with your own personal estimates for each term, and see for yourself what chance you really believe in.

    - Warren
  5. I guess you'd have to take in account the question of, "how wide spread is life?" too. I mean, just because we wont be visited by, communicate with or even listen to inteligent life out there, still doesn't mean it wont exist. If all these theories on black holes and worm holes could be true, would that not be more of a miracle than the miracle we call life on Earth?

    Our planet just shows what can sprout from "the right conditions." Life in the ground, life in the air, life on land and even life in the sea, to the very depths of the planet. It's a very over exadurated miracle if you ask me.

    We're not very advanced, not very advanced at all.
  6. Ivan Seeking

    Ivan Seeking 12,122
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    There is also the question of what we mean by "out there". Drake's equation is for this galaxy only. Include all galaxies and the answer has to be that there is a 100% [ many significant digits] chance of "intelligent life" out there; that, or the universe was made for just for us. :biggrin:

    It seems that the odds for intelligent life in this galaxy are growing by the day. Not only are we discovering new planets regularly, now we even know of ways to identify earth-like planets. If we find large numbers of those, Seth Shostak and Jill Tartar should be done soon. Also, "rare" can still be a large number in galactic terms.

    Shostak is predicting success with the Allen Array.
    Last edited: Jan 2, 2007
  7. chroot

    chroot 10,351
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    This is such an interesting and common expression of humanity. We tend to exhibit enormous individual hubris, and then express deep humility about our entire species...

    Why shouldn't we believe that we are an exceptional, advanced life form? What reason is there to not believe that all other "inhabited worlds" are inhabited only by algae?

    Drake's equation doesn't take into account the events -- improbable events -- that led to human life on our own planet. Many factors, from our large Moon to asteroid impacts to oxygen-producing cyanobacteria to dramatic climate change, all seem to have been crucial in our evolution. Even if the galaxy contains several hundred planets that could support advanced life, it's unlikely that any of them experienced the same kinds of events that the Earth experienced on the way to evolving intelligent life.

    I also believe that the universe is so large, and other stars so distant, that it greatly inhibits any one intelligent lifeform from finding any others. Sure, the world looked enormous to travellers only a centuries ago, and now we can fly to Hong Kong in a few hours and sip wine in a leather chair -- but that was just a matter of technology.

    Communicating with (and travelling to) other inhabited planets might be physically impossible. Imagine if we eventually discover another civilization broadcasting their own radio signals even so "close" as the Andromeda Galaxy. A conversation will take billions of years. Travelling there is essentially impossible. Even at ultra-relativistic velocities, the people aboard the starship will have to procreate, live, and die for thousands of generations during the journey. Who knows what "species" would finally show up at the aliens' doorstop?

    - Warren
  8. Any form of specie other than what we know on Earth would be alien. (It can even be argued that any form other than Homo sapiens is alien) But to think that not a single life form exists is thick and narrow minded.
  9. -Job-

    -Job- 1,127
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    The chances of intelligent life existing elsewhere increase with the size of the universe, but the chances of an encounter get smaller.
    I mean we would first have to be detected, and so far we have a pretty small radius.
  10. Even us our selves are aliens... To an outside race we would be no different in their eyes then they would be to us.

    One thing I do think though is if they had the technology to get here, they'd also have the technology to obliterate us off the face of the planet. Slavery anyone?
  11. DaveC426913

    DaveC426913 16,539
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    Actually, what's thick and narrow-minded is thinking there's only one valid viewpoint about this issue... :uhh:
  12. there are probably creatures living on electrons asking the same question:)
  13. :rofl: :rofl: :rofl:
  14. It's either we are alone in the universe, or someone else is out there. Both options are scary as hell.

    look up in the sky and there will be ten thousand million million stars shining at you, each glimering with a little faint shine. out of all those other stars, dont you think at least one of them are also ideal for life, no matter how conceitedly special we claim our planet is. people always say that earth is in 'the "perfect" spot. a one in a million chance.' but if you think about how many times the dice has been rolled, chances are they are out there somewhere.

    I think that hollywood has done a disservice by portraying aliens as rutheless conquerors and psychotic abductors in film after film. Its amazing that life developed on two seperate planets would ever meet, why would they waste their only other friend in the universe just for some type of conquest. You can think of it this way, lets say I am dropped off on the planet with no other life around me (pretend i can photosynthesize or something xD) and i walk around every day aimlessly wondering if i will ever meet another person. And one day, i find someone named joe, fand for all we know, we are the only ones on the entire planet. and then i kill him.

    WHY would an alien race kill the only other life forms in the known univers
  15. :rofl:

    for all we know we the entire universe could be the size of a quark to another being greater than us

    what if the big bang were just a routine experiment at the alien version of CERN and we are the byproducts of a particle accelerator
    Last edited: Jan 16, 2007
  16. DaveC426913

    DaveC426913 16,539
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    You expect logic from others yet your stance is merely belief. Why do you hold others to a standard higher than you hold yourself?

    All of which had a single common origin.
    What's 1 billion x 1? Lots.
    Reproducing isn't the problem.
    What's 1 billion x 0? Still 0.

    Sure. If they were transplanted** there. Of what relevance is that?

    This is called an imagination. It has nothing to do with the likelihood that life started out there.

    Don't get me wrong, I'm not saying I believe there's nothing out there, and I'm not saying you shouldn't continue to believe. But you can't claim to have any more logical argument than anyone else. Wait until the data's in.

    **Tee hee. I made a typo. I created the word transplaneted.
    Last edited: Jan 16, 2007
  17. what if we were some science fair experiment for an elementary school somwehre else in theuniverse. I"m sure that student has received a good grade.
  18. Math Is Hard

    Math Is Hard 4,635
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    Maybe, maybe not. You just reminded me of something David Hume said when attacking the notion of a perfect creator:

    "This world, for aught he knows, is very faulty and imperfect, compared to a superior standard; and was only the first rude essay of some infant deity, who afterwards abandoned it, ashamed of his lame performance.. "
  19. DaveC426913

    DaveC426913 16,539
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    My dog ate my planet. :biggrin:
  20. Math Is Hard

    Math Is Hard 4,635
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    :rofl: :rofl: :rofl:
  21. Who says that life is limited to beings that exhibit characteristics that we have knowledge of. For all we know, the mechanism of "life" could be realized through means other than "earthlike" conceptions. I'm sure that in certain circumstances certain compounds or energy variations could fulfill a role analogous to what water does here on earth. Maybe "life" exists in the middle of a sun? Maybe relatively (to us) extreme habitats like ultra-high energy are the perfect breeding ground for other mechanisms that are similar to the mode of behavior that we claim "life" exhibits here. Maybe we should define life before we ask if it exists elsewhere.
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