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Non-carbon based life-forms?

  1. Mar 20, 2005 #1
    What do you think?

    Is it impossible? highly unlikely? unlikely?

    I've heard of silicon-based life-forms, electromagnetic-based life-forms and flourine-based life-forms, they sure would make for some awesome and interesting creatures huh?

    But the majority of life out there would probably be carbon-based.
     
  2. jcsd
  3. Mar 20, 2005 #2
    I think its highly unlikley. At least no advanced life forms. Flourine is too reactive to be stable.
     
  4. Mar 20, 2005 #3
    How about not in a planet like Earth, somewhere where it fit the needs of non-carbon based life-forms of forming?
     
  5. Mar 20, 2005 #4

    marcus

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    It is inevitable

    It is inevitable. Water and carbon lifeforms like us will eventually
    construct surrogates adapted to live in vacuum and in cold
    and these cold-vacuum-capable beings will be able to reproduce somehow
    and that will be life

    there will be a Britney Spears model made of metal and polymers and she will be able to float around in space without a spacesuit and go to Mars or Titan if she wants and she will really enjoy having recreational sex with ordinary carbon-based guys like me, but the serious reproduction business will be back at the hive
     
  6. Mar 20, 2005 #5

    marcus

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    GoldBarz,
    you seem to be making some assumption I dont understand.

    most of space is cold gravityless vacuum, or anyway low temp/pressure

    like aboard all the comets in the oort cloud
    like on Callisto surface, etc

    LIFE EVOLVES TO FILL NICHES, i.e. to take up livingspace

    so you can even prove as a kind of theorem that
    carbon-life is a STAGE IN THE EVOLUTION of lifeforms adapted to cold vacuum.

    personally I am not so interested in mere lifeforms, what interests me is lifeforms that can write poems and music, maybe dance the polka too.
    I assume that things made of metal and plastic and rubber can do these things, and can reproduce themselves and modify their own programming as well.

    Given a few millennia any intelligent carbon species ought to be able to launch an intelligent metallic species able to maintain a high civilization, mine asteroids, and take care of business in vacuo.

    So if there are any carbon species out there (besides us) then i would guess there would likely be even more widely dispersed noncarbon species as well. One follows from the other---given a little time to develop
     
    Last edited: Mar 20, 2005
  7. Mar 20, 2005 #6
    But it is proved that carbon is the best to make life out of, other ones like silicon, ammonia, flourine, or even electromagnetic is possible but unlikely. That is why I said it is possible but carbon-based life forms would surely outnumber non-carbon-based life forms.

    EDIT: I am not talking about man-made ones, I am talking about natural made ones
     
  8. Mar 20, 2005 #7

    marcus

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    I am talking about NATURE-made self-reproducing forms of life.

    intelligent carbon lifeforms can be considered part of nature
    and part of an evolutionary process.

    it does not matter to me how the first organism comes into existence if it can reproduce itself, I think that carbon-lifeforms are apt to produce noncarbon forms
    just as seadwelling species are apt to give rise to species that can live on land

    I think you are making arbitrary and unnecessary distinctions.
    You seem to think that carbon and noncarbon are absolutely separate categories of life. I see no reason to suppose that. I think that one can emerge from the other, one can give rise to the other.
    Once it has intelligence, life can change its chemistry

    as an analogy: mosquito larvae live in the water as wrigglers and eat algae
    and at a certain point they pupate and what emerges from them can live in the air and eat your blood, one form has given rise to another.
    so likewise I believe that carbon forms can give rise to noncarbon forms of life and that making the distinction too sharply will dull and restrict the thoughtprocess
     
    Last edited: Mar 20, 2005
  9. Mar 20, 2005 #8

    marcus

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    I dont believe this has been proved. I do not even think you have a well-defined meaning for "best".

    If I personally was designing a species of self-reproducing organism to live in the asteroid belt, or on comets, I might choose to have them make themselves out of metal. It might be the "best" material for a lifeform to be made of, under the circumstances. they might look like large battery-driven insects. they might tend potted plants with photovoltaic leaves.

    I would insist that they be able to live comfortably in the vacuum and that they be able to write beautiful sonnets (a type of poem I like) to each other.
     
    Last edited: Mar 20, 2005
  10. Mar 20, 2005 #9
    Oh, so you do believe non-carbon based lifeform (natural made and not made by some advanced alien civilization, like life here on Earth except not carbon-based) can emerge and develop intelligence, I dont know why we are arguing since I agree.
     
  11. Mar 20, 2005 #10

    marcus

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    that is not what I said

    I believe from what you say that we dont have a common basis of concepts. I dont want to argue, and have no interest in trying to persuade you of anything.

    At this point all I want to do is present my viewpoint in case any one else is listening.

    Living organisms are selfreplicating machines that can modify themselves by various evolutionary processes. they replicate but they can also split off into different species and change.

    Humans are part of nature. the machines that humans design and build are natural occurences and part of nature.
    Humans can build intelligent selfreplicating machines capable of modifying themselves. And they will very likely do that. those machines will be living organisms and they will be part of nature. They will have arisen naturally.

    Carbon life can spawn non-carbon life, obviously. It is part of how life works that carbon life forms can evolve enough intelligence to initiate non-carbon life forms.

    the non-carbon life forms that emerge will be true, natural, living organisms. they will reproduce. they will evolve. they will come to occupy niches in the environment where they have some advantage over carbon-type life. this is just how nature works.

    One may speculate that the non-carbon life forms will thrive in low pressure and temperature environments-----cold vacuum. there is a lot of cold dry vacuum around for them to populate. the warm wet pressurized environment we need is comparatively rare.

    My private opinion is that it is harmful to the mind to make too sharp a distinction between carbon life and non-carbon life. It is all life and ONE CAN EMERGE FROM THE OTHER. Life and nature do not recognize this distinction. It is not a natural division. One can even say that noncarbon life can EVOLVE from carbon life since a man can "give birth" to a machine that is in certain special senses like himself but composed of different materials.

    Therefore I surmise that either we are alone in the galaxy and the earth is the only planet with a technical civilization, or else there are other technical civilizations---in which case I consider it likely that there are cold vacuum environments inhabited by non-carbon lifeforms.

    It may well be that there is no planet in this galaxy where noncarbon life has evolved from primordial clay or soup. It may well be that the only life that ever evolves early in a planet's history is carbon life. I am not interested in whether that is true or not. Even if the only life that ever emerges from primordial conditions is carbonbase, it can still be the case that the main type of life populating the galaxy is noncarbon. this would merely mean that the carbon life would OLDER than the noncarbon. it would not, by that token, be more natural or more life-like

    in my view, noncarbon lifeforms will tend to arise from carbon lifeforms, as we already see beginning to happen
     
    Last edited: Mar 20, 2005
  12. Mar 21, 2005 #11

    ohwilleke

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    Silicon is as plausible of any of the non-carbon possibilities, primarily due to its chemical similarity to carbon, as it is another non-metal in the same column of the periodic table. Carbon is more common in the universe, so one would expect carbon based life to be more common, but as noted above, life forms in a niche, and a silicon rich niche would hardly be surprising. Also, once life establishes itself, it would tend to squeeze out competition.

    Life with a methane based chemistry seems more likely than a Flourine cased chemistry, simply because we know of many places where there is abundant atmospheric methane.
     
  13. Mar 21, 2005 #12

    cronxeh

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    The question is way too complex. Firstly you go about finding alternatives to C-12 in a following way:

    1- how many bonds can alternative base chemical make? what if you have multiple base chemicals - which would those be, how many possible combinations do you want?

    2- how does our brain work in terms of perception, memory, data acquisition/analysis, etc - what is the exact mechanics so that we can look for alternatives from there and see exactly what the properties of alternative chemical compounds should be - it would go into the solid state discussion from there

    3- how does the 'organism' make sure it's survival? if its not some vast array of interconnected matter that feeds upon some cloud of matter - how long would it live? how many chemical compounds and which one would it need to sustain?

    this questions is so complex that there are about hundreds of unknown if even you wanted to answer one simple one - which one of the chemical elements could be an alternative?

    it could be Uranium-235, or some radioactive element that decays fast, and then you have an even more complex system, etc. Or the answer could be far simpler - that out of all the chemical compounds in the Universe, our organic life form is the most stable one.
     
  14. Mar 21, 2005 #13
    There is two other possibilities i can think of theoretically.

    First Dark Matter take up a lot of the mass of the universe and cosists of stuff we dont even know of. There is a high probability that some unknown element exists there that could form "life"

    The other thing is that theoretically, anti matter carbon could be used to create life in a anti matter dominated place of the universe...
     
  15. Mar 21, 2005 #14

    Well . . . my understanding is that dark matter is very weakly interactive
    ( hence the W.I.M.P denomination ) Ìts dark for a reason... so the chances of something complex emerging from it is... well, wimpy :rofl: .
    This is by coincidence equivalent to the chance of finding an area of the universe dominated by antimatter. Such an area would have so humongous of a firework at its border that we would certainly have found it at this point.

    Was there ever any serious studys on possible alternative chemistrys for life or anything taking these elements in account ?

    Another interesting outshot of this concept is the possibility of those carbon based life transforming themselves into metal life forms. The idea of "downloading" ourselves into cyber-brains has been out there for awhile but I believe it is more likely than people think. Think about what actually separates us from the possibility. A- Computers with computing power equivalent to the human brain. That should be attained within a couple decades.
    B- A deep understanding of the neuropsychology i.e the neurological structure of thought and consciousness. From what I understood of vulgarized neuropsych. texts, this is within reach as well. C- A suitable brain/computer interface to accomplish the transfer. This also is an area where extensive research is being accomplished and where impressive results have been attained.*

    This would have enormous consequences in every aspects of human life but the impact on space exploration would be particularly interesting. Anyone up to climb aboard the next Voyager, Mars Rover or Casini ? I say yeeha ! :biggrin:



    * On a side note, I strongly recommend the Sci-Fi novel DIASPORA by Greg Egan. It deals with the subject of the future of human life form in a truly mindblowing way !
     
  16. Mar 21, 2005 #15
    What I am trying to say is that we shouldnt just think that there are only carbon-based life out there, yeah we should focus on carbon-based life but we shouldnt rule out the non-carbon based life.

    Computers arent nature made, you are misunderstanding something marcus, I am saying silicon-based lifeforms emerging the way that we emerged

    So is the idea of non-carbon based life forms plausible?
     
  17. Mar 21, 2005 #16

    marcus

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    I also say yeehaah!

    Furthermore humans are just as natural as primeval slime and broth and for humans to "download" themselves into metal lifeforms is as natural
    as singlecell organisms arising from the primal goo.
    therefore we can regard the emergence of metallic (or other noncarbon) lifeforms from us, if it happens, as a STEP IN THE NATURAL EVOLUTION OF LIFE

    by the principle of mediocrity, if it looks likely to happen here with us (which it does to me and I think from what you say also to you, Meanhippy) then the same natural evolutionary step is apt to have occurred in other places.

    So if there is anytype life at all out there, and it has evolved intelligence (with the ability to implement itself in alternative materials) then one can argue that there is going to be a bunch of non-carbon life-forms.

    It is also possible that silicon turkeys have evolved directly from the primal goo. People used to speculate about that in the Seventies, I believe. Like Carl Sagan speculating about alternative non-carbon chemistry biota. This is interesting too, in a limited way and up to a point.

    but in visualizing the future it is kind of irrelevant. i think one has to look at the available niches for life and say that metallic lifeforms are destined to be more widespread and numerous.
    Organisms which can thrive and multiply in cold dry vacuum environments in other words.

    and i think in the long run it is irrelevant whether such organisms arose from primal goo or had carbon-base ancestors who constructed them and downloaded their civilization into them.

    things that can spawn and multiply in the big niches, whatever their longago origins, are destined to be predominant forms of life.

    this is why I hope that in years to come the Aluminum Chickens of the Asteroids will have learned from us how to compose sonnets and sonatas.
     
  18. Mar 21, 2005 #17
    Come on marcus ..

    You're slipping a bit here in your categorizations. I remember one time in a response to one of my topics you categorized the CMB Radiation as a "Perky Curve". Can't get any better than that! LOL!
     
  19. Mar 21, 2005 #18

    Chronos

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    Agreed. I don't think there is any such thing as artificial life, just life and non-life. If it can replicate and evolve, it's life by any reasonable definition. Possessing a traditional biological heritage is irrelevant. If my life form can encode and execute its replication program more efficiently than yours, I am the dominant life form.
     
  20. Mar 22, 2005 #19

    marcus

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    thanks for coming to my support
    its a minority POV, and I have no interest in arguing so it could be about time to bail

    for me (Chronos, Meanhippy, anyone who can sympathize with this viewpoint) the important thing is not philosophical distinctions but
    practical consequences in the form of expectations of what you find out there.

    maybe there is no other life in the galaxy besides us
    but if there is some, then i think it is quite likely to have evolved to live comfortably in the big niche----the dry pressureless emptiness.

    maybe I am missing something obvious
    my expectation is that humans will create self-replicating intelligent organisms able to live in space, they might look like a cross between a contemporary spacecraft and an insect, or like something else entirely. they will be at least partly metallic, and they will practice some form of metallurgy to get material to make more of their kind. they might be very small, or they might not. they might, at least at first, have implanted human personalities in them.
    once something like that is created, it can evolve on its own according to the usual rules of evolution, possibly becoming more diverse and specialized

    because I expect humans to create vacuum-dwelling lifeforms, I think it is likely that other soft wet intelligent organisms (if they exist) will also produce them. it is part of a tendency that life has to fill available niches.

    so THE KIND OF LIFE I EXPECT we shall find, if we find any at all, is life which is adapted to the biggest environoment: the cold dry vacuum, and the kind of life adapted to those environments is apt to be non-carbon
    and indeed not constantly dependent on liquid water either

    I havent considered carbonbase forms with an exoskeleton, maybe I should, the immediate drawback is the tendency of their organic fluids to boil at low pressure.
     
  21. Mar 23, 2005 #20

    Nereid

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    Who knows? Maybe the most 'common' form of 'life' in the universe is based on hyper-super-symmetric particles, which have a characteristic life of 10^-35 s? Measured in terms of our carbon-based characteristic time, these critters have already gone through zillions of 'universal generations'! Or perhaps it's dark matter ets which 'energise' their 'cells' by extracting third-order perturbations from neutrino oscillations? Or - per marcus and Chronos - the 'original' carbon-based life of ESO 998877-12345 Bax long since downloaded into strangelets, and are living happily ever after in the cores of magnetars and the trillions of white dwarfs throughout the universe?

    If we take a scientific approach - how could we tell?
     
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