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Why do people ask why life exists?

  1. Dec 6, 2004 #1
    People always say "It's so surprising that we exist" or "It's so surprising that life exists in such a chaotic universe".....There was even an article in Discover magazine a while ago where an Astrophysics professor was discussing how the Universe has a series of constants and properties, that if even very minusculely altered, would eliminate life.

    My question is...why are people surprised that there's life? We clearly exist because we can THINK about this stuff. If we weren't to exist...well then we wouldn't be wondering about this, would we?

    Sure, if we slightly change the force gravity exerts or whatever, life wouldn't exist.....but it does! :bugeye:

    What does everyone think?
     
  2. jcsd
  3. Dec 6, 2004 #2
    I totally agree. I remember first year astronomy class (last year) when the prof was talking about that same thing. I've always thought that the idea of 'these that things had to be so precise and the factors that could not be changed life would not exist is so amazing' debate to be blatantly obvious. Sure, countless factors could have led to primordial demise, but they didn't. Is that amazing? Not really. Why is it amazing? Because of the probability that all these factors coming together to create life (and ultimately us) is so small. So what again? The chances are improbable, not impossible. Case in point
    1.) The conditions required to create human life as we know it are extremely rare
    2.) Last time I checked, other planets with human (or any life for that matter) are also extremely rare.

    Therefore we should not be suprised, we were just the ones who won the proverbial lottery of odds. It's one in a <insert huge number here> and we just came up number 1.

    I think.

    Jordan Veale
     
  4. Dec 6, 2004 #3

    marcus

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    Jordan V, I agree with what you and fomenko said as far as it goes, what you say makes complete sense, but there is another part to it.
    Someone in Waterloo Ontario has constructed a theory explaining WHY the series of constants is what it is.

    this theory does not have anything to do with life. it is an attempt to explain why certain of them have the numerical values they do (which HAPPEN to make complex chemistry with a lot of elements possible but that is coincidental)

    recall what fomenko said
    "a while ago where an Astrophysics professor was discussing how the Universe has a series of constants and properties, that if even very minusculely altered, would eliminate life.

    My question is...why are people surprised..."

    Well. I wouldnt say people should necessarily be surprised that, say, this key number alpha is 1/137
    but they should notice the number (which indicates the strength of electric interactions compared with others) and realize that there is something to explain there.

    Some scientists harp on the fact that alpha needs to be very close to what it is, in order for there to be longlived stars and rocky planets and carbon chemistry etc etc. But I suspect they put a big emphasis on that just to impress people with the importance of that number and get the attention of the audience.

    No matter whether they harp on it or not, there is still the question of why
    the electric interaction coupling constant alpha turned out to be right around 1/137. It is a serious question, not about life either. It would be nice to have an explanation.

    there is no evidence that there is more than one universe
    we have no indication that there is anything else besides this universe
    we have no indication that alpha is "just an accident" that happens to favor life
    there could be some good reason why it is what it is

    and the other constants in the basic series, too.

    =========
    my feeling is you shouldnt feel obliged to be interested in this. I dont try to
    persuade anybody that it is exciting or surprising. If it is, for you, fine, and if not, fine too.
    =========
    but in return how about you dont knock it if somebody else finds the question of why those numbers are what they are quite fascinating.
    I do, for instance. It is almost the most interesting question for me that is.

    ========
    there are not yet any clearly good theories.
    the only reasonable at all theory I know of is one that I dont especially believe, but might be true-----it hasnt been conclusively disproved.
    it is by Lee Smolin, at perimeter institute, waterloo, canada
    it is explained online in this article he wrote:
    Scientific alternatives to the anthropic principle
    http://arxiv.org/hep-th/0407213
    you click on PDF to download
     
    Last edited: Dec 6, 2004
  5. Dec 6, 2004 #4
    Archers Analogy

    To UpCreekl: I'm glad you agree.

    However, there is this reply that goes: "If 200 trained archers simultaneously fired arrows at you, and they all missed, wouldn't you be surprised and investigate it? Even though IF they hadn't missed you would NOT be alive to think about it?"

    I somehow think that's a bad analogy.
     
    Last edited: Dec 6, 2004
  6. Dec 7, 2004 #5

    Garth

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    What we are discussing here is the Anthropic Principle, which while it does get a bad press at times, is pretty innocuous in its Weak form, "The world is as it is because we are". (Stephen Hawking) It simply means that of all possible explanations for the state of the universe those that result in a universe unsuitable for life cannot describe our own universe.

    This requirement does place certain constraints on possible cosmological and physical theories, they have to be propitious for life, because we are here debating them!

    This constraint can yield, and has yielded, predictions as to limits within which any, as yet unknown, physical parameters have to lie. The nucleo-synthesis of carbon and the beryllium-carbon resonance famously predicted by Fred Hoyle being an example of one such parameter.

    Think of a new theory, is it propitious for life? No? Well then abandon it as failing the empirical test. Is not then the Weak Anthropic Principle a scientific principle with predictive power? I cannot see how it is not.

    Smolin indeed criticises it as not having any such predictive power. Yet as I have pointed out elsewhere, although his Cosmological Natural Selection hypothesis in itself does not refer to the existence of life, nevertheless it has resulted in a universe in which Smolin and the rest of us are alive. The CNS ‘simply’ maximises the number of black holes in any universe, but also we may consider any other theory that determines the physical constants, the fact that they may not refer to biological requirements does not itself alter the inescapable fact of our existence. We therefore may ask why should this process produce a biologically propitious universe and not otherwise?

    Of course it is perfectly possible to believe that the answer to this question is a pure ‘fluke’, a “happy coincidence”, because if it were not so we would not be here to contemplate the fact, but others may choose to believe differently. Here the ‘hand of physics’ points beyond itself to the metaphysics of unobservable other universes or a Grand Design or whatever and from the point of view of the scientific method it is difficult to distinguish between these different responses. One person may be happy to look where the hand is pointing and another not, the choice is yours!

    Garth
     
  7. Dec 7, 2004 #6

    Nereid

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    Excellent posts marcus and Garth!

    If I may, I'd like to bring one aspect of this back to science. "[W]hy should this process [CNS] produce a biologically propitious universe and not otherwise?" Garth said. If we are doing science (and not philosophy), shouldn't we ask "Even in principle, is this question amenable to being tested by observation or experiment?"
     
  8. Dec 7, 2004 #7

    Chronos

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    The weak anthropic principle does not predict anything, in my mind. It merely reminds us that something must be wrong with any theory that predicts life cannot exist. The existence of life is merely an observation: no different than the sky is blue or the sun shines. We would be equally justified rejecting any theory that contradicted those observations. I think it is misleading if not silly to call anthropery a 'principle', much less a theory. Wouldn't it seem bizarre if someone proposed 'the sun shines principle' as a predictive model?
     
  9. Dec 7, 2004 #8

    turbo

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    My thoughts exactly Chronos! The anthropic principle is not predictive and cannot be falsified, therefore it is not science. When I first read Smolin's paper on a universe fine-tuned to produce black holes, I thought that he was trying to make a humorous point that we can take any product of our observable universe and hold it up as an example of how the universe must be tuned "just so" to produce that one product (lots of black holes, in this instance).

    I agreed whole-heartedly with him when I thought he was being sarcastic to the anthropic crowd - now I don't know... We could as easily argue that the universe is fine-tuned just the way it is in order to produce quasars, pulsars, gas giants, or even Hello Kitty merchandise (which wouldn't exist without us) - an absurd extension of the "logic" of the anthropic principle, perhaps, but if one holds Hello Kitty in high regard, perhaps it could be viewed as a worthy end-product to which the universe "aspires". :rofl:
     
  10. Dec 7, 2004 #9

    Garth

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    But you can propose that if you want to! Over a hundred years ago they knew the Earth, and therefore the Sun, was older than several hundreds of millions of years, yet the maximum duration of the Sun's gravitational virial energy was some thirty million years. In those days if you had proposed in solar physics a 'the sun (still) shines principle', you would have concluded that there had to be another source for its energy, which is what they actually did do, and Jules Verne included it in his novel "20,000 leagues under the sea". (The Nautilus was powered by the 'same energy source as the Sun') The fact that nucear fusion was not discovered until the next century does not alter the power of their prediction!
    There is of course another similar principle, "The sky is dark at night". Olbers paradox places predictive constraints on all possible viable cosmologies. Only those that produce a dark night sky pass Nereid's 'observation or experiment' test.

    Garth
     
    Last edited: Dec 7, 2004
  11. Dec 8, 2004 #10
    Anthropic Principle

    Very good posts everyone, although a bit heavy for my 17-year old brain :tongue2:

    What I'm understanding is the Anthropic Principle is relatively falliable because all it says is that "The Universe's laws must be exactly so to produce the universe we see now". Sounds like circular reasoning to me.....

    Marcus brought up a good point which basically answers my question
    there could be some good reason why it [the constant]is what it is
    It does seem very curious that since we have no testable theories of the existance of other universes, and that OUR Universe is (probably) the only one, that a law/constant turned out to be the way it is.

    Anton
     
  12. Dec 6, 2011 #11

    Edi

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    I think that the big mistake here is that people somehow forget that human life (or any life on this planet, for that matter) is not the only organism, that can think and be called 'alive'.
    That is, even if the universe would be tuned differently, with gravity stronger or weaker or whatever, then the universe would be a different place, yes, but with a high chance of having some form of life in there. Then that form of life would, eventually, ask the same question - why is the universe just right for our life to exist? .. and now it is possible to see that asking such a question is quite absurd, actually.
    Life adapts to the universe, not the other way around!

    ;)
     
  13. Dec 6, 2011 #12

    Ryan_m_b

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    I agree with the sentiment Edi but I'm still going to have to lock this thread. If you check the dates on the posts you'll see it's a 7 year dead thread.
     
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