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What is the role of life in the universe?

  1. Nov 14, 2004 #1
    I’m in the process of reading a book by Paul Davies called The Origin of Life, and in it, it seems apparent that life began quite suddenly after the earth was created. 3.5 billion years ago or maybe even earlier. This to me seems to indicate a couple of extraordinary things about life. First is that not only doesn’t a planet need hospitable conditions for life to originate, but also alongside the evolving universe, life comes into existence shortly after the big bang. We could however, say that due to the enormous numbers of stars and potential planets existing in the universe there’s bound to be many planets harboring life, or people could just say that life is a highly improbable outcome.

    But the view that life is a highly improbable outcome seems almost ridiculous, and if we still adopt the view that it is a rare event, we’re faced with the realization that it was a rare event that happened relatively shortly after the beginning of the universe.

    If on the other hand we find that life is a crucial part of the universe, does this say anything about the universe its self being fine-tuned for life? And if so what role does life play in the universe?

    Freeman Dyson (Dyson, 1988): “there are good scientific reasons for taking seriously the possibility, that life and intelligence can succeed in molding the universe … to their own purposes…It appears to me, that the tendency of mind to infiltrate and control matter is a law of nature.”
     
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  3. Nov 14, 2004 #2
    As the universe expands we find more complex structure emerging, first stars and galaxies, planets and moons, then more and more complicated forms of life on earth? It seems curious that life on earth arose about the same time that the universe accelerates in its expansion.

    It's not that these very complex structures are impossible to form, but it is only improbable, and that may be the point. Even in quantum mechanics there is a superposition of alternatives from which only one possibility is chosen in a given measurement. And that choice is less probable than the whole.

    What I think is going on is the effect of a conservation of information or entropy in the universe. There is some uncertainty in our measurement and observations of anything in the universe. But above all, what is absolutely certain is that there does exist a universe. There is no question about that, ever. This is true at all times.

    Information theory tells us that entropy is related to information through probabilities, that the information content of an absolute certainty is zero, and more information is contained in the more improbable events. We learn nothing from a choice of an absolute given. There's no surprise in learning it. But if some highly unlikely event takes place, we sit up and take notice.

    So if the information content of the universe as a whole must be conserved at zero, then there must be something in the universe to balance all the effects of entropy in the universe. If the expansion itself of the unverse is seen as an increase in entropy, then there must exist forces to reduce entropy. And life may be that counter-balance to entropy in the universe. Our purpose in life may be to perfect form and structure, at least that seems to be how we define progress.

    But how would you prove that the universe is constructed by principles that balance entropy? If the certainty that the universe exists is 100% even when the universe was so small that the first quantum mechanical situation arose, then you know that conservation of information is active in the principles of quantum mechanics. When the perfect symmetry of the universe broke and alternatives to that symmetry became possible, you know that the structures that arose must have represented a decrease in entropy (= increase in information) that offset the entropy of so many possible alternatives.

    One encouragement in this perspective is that recently we are told that even black holes conserve information. And I have read that information is conserved for all horizons, even the cosmological event horizon at the edge of our observable universe. It seems that at the edge of our view of the universe, even there objects are receding so fast that we observe redshifts increasing and processes slowing down in what is called a big freeze. So I wonder if this all contributes to a reduction of entropy or a conservation of information in the rest of the universe.

    Yet, one of the questions I have is how is the universe as a whole defined for the purposes of information conservation. Is information conserved for everything that exist at this instance of time? Or is information conserved for everything in our light-cone, for everything we observe?
     
  4. Nov 14, 2004 #3

    marcus

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    Please give us the title of the book or article which you refer to as
    "Dyson, 1988"

    It will be in the bibliography of Davies book, which you are in the process of reading, or so I would expect.

    I would urge you to read something about CNS (cosmic natural selection) for balance.

    Try "Scientific Alternatives to the Anthropic Principle" by Smolin

    the universe may be fine-tuned to produce massive black holes----which result in offspring universes with approximately the same physical constants----and only coincidentally to be hospitable to life.

    the smolin multiverse theory is unusual in that it generates readily testable predictions-----one can check it by common sorts of astronomical observations

    Indeed maybe it has already been ruled out----we are waiting to hear more on that.


    =============

    BTW this is a side issue but the first generation of stars after the big bang were metal-poor
    many of the familiar chemical elements had not been synthesized in significant amounts

    it takes several generations of stars, forming and exploding or blowing off their outer layers, to build up an interstellar medius rich in heavier elements like nitrogen, carbon, oxygen, silicon, calcium etc
    so that rocky planets can condense and harbor complex chemistry

    early stars, if they had planets, would have had planets consisting mostly of hydrogen and helium, plus a little lithium-----not very promising.


    the big bang (beginning of the current expansion phase of universe) is estimated at 13.7 billion yrs ago.

    As far as we know life is only about 3 billion yrs. old.
    Life did not come into existence, as far as we can tell, soon after the big bang.

    It may have. But according to the little evidence we have it took a long long time after big bang for life to appear.

    Also the evidence on earth suggests that life stayed SINGLE CELL for most of that time. Like for 2 billion years it just sat around and did not get the idea to but cell and cell together.

    Multicell life only goes back to (approx, roughly) 0.6 million yrs.

    So if some intelligences fine-tuned the U to promote multicell life they seem to have botched the job. they were incompetent bunglers.
    they produced something way mondo sub-optimal.

    By contrast the U seems very well tuned to produce black holes.
    black holes have been observed at high redshift, in other words very far back in time. this is in line with the CNS hypothesis. Moreover, black holes are demonstrably plentiful---most galaxies are now believed to have one or more central ones, the milkyway has two. And lots of stellarsize ones have been detected.

    Having an ample periodic table of stable elements, capable of rich chemistry, may be a SIDE EFFECT of universes evolving in ways favoring the formation of black holes---this is explained, for instance, in the article cited earlier.

    I think Freeman Dyson may have changed his tune since the 1980s. He is still writing but I havent heard anything more about the role of intelligence in cosmology-----the idea was a favorite of his in the 1970s and you cite a 1980s reference---so he may think differently now. Any recent source?
     
  5. Nov 14, 2004 #4

    http://astro.elte.hu/~bab/Role_Life_Univp.htm

    This is the article, but I think it’s in one of his books Imagined Worlds or Disturbing the Universe, whichever he wrote back in 1988.

    Thanks for the reading advice, I’ve already taken a look at Smolin paper, but I was under the impression that black hole’s producing universes had been ruled out early this year.
     
  6. Nov 14, 2004 #5

    Garth

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    Is the Smolin model an alternative to the Anthropic Principle and its coincidences? The theory depends on the physical constants that maximise the number of black holes also being propitious for life.
    But wouldn't that be rather a coincidence?

    Garth
     
  7. Nov 14, 2004 #6
    Does anyone here consider the possibility of creationism?

    Just curious. I don't want to start a fight, but it could be a posbility?

    We as humans, naturally want to think there is a heaven.
     
  8. Nov 14, 2004 #7

    selfAdjoint

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    Scientists assert about creationism that it is not a science, because (a) it assumes its conclusion, and (b) it does absolutely no real research. Whether you take the "young earth" kind with literal creation in 4000 BC or so and Noah's flood and all, or the "old earth version, with no big bang, and in either case no evolution of species, it's false, has been falsified by genuine science, and cannot be used to erect a scientific alternative to standard cosmology and geology, let alone evolution.

    Maybe you need a heaven, having perhaps been brought up with the idea, but many others have no need for it. Marcus, up on the Strings, Branes & LQG forum, just quoted Laplace's great line: asked by a bishop why he had not mentioned god in his great book on celestial mechanics Laplace replied "I found I had no need for that hypothesis." even so for heaven, to many.
     
  9. Nov 14, 2004 #8
    Absolutely.

    So where did this idea come from?

    Not only did it not happen soon. But it didn't even happen in a lot of places as far as we can tell.

    So there wasn't just lot of time for this improbably event to have occurred, but it also had billions upon billions of opportunities to occur even within our own galaxy.

    Yet to the best of our knowledge it has only occurred once in all of those opportunities. (but we really have no clue whether it occurs more often or not)

    There may yet be other life forms right here in our own solar system that we simple haven't discovered yet. The idea that life may have existed on Mars as primitive microbes hasn't been completely ruled out. We'll never know whether life might have started on Venus at some time in the past. There's still possibilities that life might yet exist on the moons of Jupiter or Saturn. We just don't know.

    Should we ever happen to actually find an independent life form in our own solar system all of a sudden we'd pretty much have to conclude that it isn't an improbably event at all. Life might exists are just about every observable stars system around us. We can't even really tell whether small planets might exist. Whether such planets might contain life is totally beyond our ability to observe.

    We simply don't know how probably or improbable life might be. Once a solar system has formed and all of the chemical components are in place life might arise fairly easily at that point. We just don't know.

    Even when life does evolve, how probable is it to become technological? The dinosaurs existed for something like 65 millions years with no evidence that they were becoming technological in any way.

    Do you realize that humans have only been seriously technological in the past couple hundred years!!! Imagine how technological we will become should we happen to survive for even 1000 years (as a technological species). Current human behavior doesn't look promising for such longevity though. Our technology is driven mainly by greed and financial goals. We are a throw-away wasteful polluting selfish species. Some would argue whether humans actually qualify as "intelligent" lifeforms.
     
  10. Nov 14, 2004 #9

    Garth

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    I think not "wanting to starting a fight" is probably being a bit too optimistic!!

    Nevertheless, for my pennyworth - it depends on what you mean by 'creationism'. The term is normally hijacked by the "Genesis 1 is literally true, - with a 6 x 24 hour day creation - about 6 to 10,000 years ago" brigade.

    However, all down the ages right up to the present day there has also been a number of people who answered the question, "How do you explain it all?" by saying, "God".

    Such answer is by definition a statement of faith, but equally the answer "There is no such God" is also a statement of faith. The matter cannot be resolved by scientific proof one way or the other.
    As I have posted before on these forums:
    Garth
     
  11. Nov 14, 2004 #10

    marcus

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    Thanks. I looked in the selection you linked to
    and found the reference to Dyson
    Dyson, F. 1988, Infinite in all Directions, Harper, New York, N.Y.

    By coincidence, I have Dyson's "Disturbing the Universe" book 1979.
    I couldnt find anything like this in it---in a quick look.

    But I distinctly recall a Scientific American article by Dyson from the 1970s---a special issue on Energy---one of the September specials.
    Or earlier than 1970s. And he definitely said we probably will not understand cosmology until we have a better idea of the role of intelligence in it. The suggestion was that accidentally evolved lifeforms like us may have tinkered with the fundamental constants. May even have overseen the production of the universe as we know it. May have found ways to outwit collapse or chill----fire and ice----if threatened by them.

    exciting stories, good stimulus for speculation---and Dyson is good at that.

    Your link was interesting as well.

    I see it discussed Smolin CNS. And critically!

    that is interesting too, and if you find a reference for CNS being refuted earlier this year please post it! I am not convinced that it has been refuted with certainty and would like to know of any evidence. I still feel that the Fat Lady has not sung yet, for CNS.
     
  12. Nov 14, 2004 #11

    Garth

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    Although I agree with everything you say about 6-day creationism, about that quote:
    Actually it was the Emperor Napoleon who asked Laplace that question. Those who quote it as a knock down argument for atheism ought to be aware that Laplace was a practicing Catholic all his life.
    What he had just explained to Napoleon was his theory of the stability of the solar system and planetary orbits. Newton had been aware that the perturbations of other planets might push the Earth off its normal orbit and consequently made life impossible. He was prepared for God to "stick his finger in" and push the Earth back onto its correct orbit, as one might correct an old clock. Laplace's research had convinced him that this was not necessary as the perturbations 'evened out' over time (excuse my hand waving explanation for his detailed mathematical analysis!). And so he did not need to bring God into it.
    Actually you could (I would) argue that if God had had to intervene in the Creation as Newton had surmised then that Creation would not be perfect but like a badly built clock that constantly needed correction.

    Garth
     
  13. Nov 14, 2004 #12
    L.Susskind is against Smolin's theory. He gives his reasonings in this paper
    http://arxiv.org/abs/hep-th/0407266
    he denies the validity of CNS in this excerpt:
    "The implication (Susskind gives a reference of a paper of Maldacena here) is that if there is any kind of universe creation in the interior of the black hole, the
    quantum state of the offspring is completely unique and can have no memory of the initial
    state. That would preclude the kind of slow mutation rate envisioned by Smolin."
    -----------------------------------------------------------------------------------

    Respect to the origin of life, I remember that was fascinated 5 years ago more or less about how life and intelligence can emerge from nothing, just like magic. i remember that i went to my local library (I hadn't internet in that epoch) and picked a book of Oparin. it was too technical for me, but it seems that that book is a classic. there was a lot of chemistry in the book, one of the things that I remember principally is his hypothesis about life emerging from structures called coacervates. It seemed very strange that consciousness and intelligence and mind could emerge only because some chemical processes, but i accepted it. My vision of it has changed over the years, now I think that life is a common characteristic of all matter (though in elementary particles is very poorly developed) and that this quality of intelligence enhances as there is an increasing of the complexity of the system (for example in the formation of the brain). It seems to me that the aparition of intelligence was predestined even after the first seconds after Big Bang, I'm sure that there's some obscure law guiding the process of acquisition of higher levels of intelligence and sentience, just we haven't discovered it yet that law
     
  14. Nov 14, 2004 #13

    Chronos

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    Judging by some fairly recent correspondence, Dr. Smolin has not yet thrown in the towel on CNS.
     
  15. Nov 14, 2004 #14

    selfAdjoint

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    Well, I hope you weren't converted to panbiosis by Oparin! He wrote back in the thirtiies and I don't think his coacervates are still considered part of the early history of life. Rather than trying to mimic cell walls, reseachers are now thinking of two-base RNA's and self-catilyzing molecules. To me panbiosis is just a form of giving up on chemistry, which is still under way to finish the job of explaining life.
     
  16. Nov 14, 2004 #15

    marcus

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    meteor I think what susskind said was not carefully reasoned
    but seemed more like a hasty innuendo. it does not constitute an solid objection to CNS.

    I was wondering if you brought it up seriously or humorously.

    here is the full quote and the reference [14] to Horowitz Maldacena paper:

    ---quote---
    Finally, we have learned some things about black holes over the last decade that even Stephen Hawking agrees with [13]. Black holes do not lose information. The implication [14] is that if there is any kind of universe creation in the interior of the black hole, the quantum state of the offspring is completely unique and can have no memory of the initial state. That would preclude the kind of slow mutation rate envisioned by Smolin.

    [14] G. T. Horowitz and J. Maldacena, The black hole final state,” JHEP 0402, 008 (2004) [arXiv:hep-th/0310281].
    ---end quote---

    the paper he cites by Horowitz Maldacena is a proposal, not a proven result.
    ---quote hep-th/0310281 abstract---
    We propose that in quantum gravity one needs to impose a final state boundary condition at black hole singularities. This resolves the apparent contradiction between string theory and semiclassical arguments over whether black hole evaporation is unitary.
    ---end quote---

    They apparently assume there is a singularity. A boundary. It is just the LQG point that spacetime does not end, where there used to be the classical singularity. One does not need to impose a final state (as Horo and Malda believe necessary.)
    Their paper is speculative, they admit, and takes string theory (?) as point of departure

    ---quote from Horo and Malda conclusions---
    We have suggested a possible resolution of the apparent contradiction between string theory and semiclassical arguments over whether black hole evaporation is unitary. By imposing a final state boundary condition at the black hole singularity, one circumvents the usual causality problem and obtains unitary evolution even in a semiclassical treatment. The ideas in this paper are completely consistent with the ideas of Hartle and Hawking about a unique wavefunction for the universe [11]. It is precisely this uniqueness that saves the day in black hole evaporation. Notice that a unique initial quantum state does not imply a unique macroscopic state, we could have a superposition of different macrocopically distinct universes. Our proposal is clearly very speculative, and we have not given any constructive method for computing the black hole final state. In principle, this can be deduced from a precise calculation of the evolution |psi>_M arrow |psi>_out
     
  17. Nov 14, 2004 #16

    marcus

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    meteor I think what susskind said was not carefully reasoned
    but instead seems more like hasty innuendo. I do not think it comes to grips with CNS or constitutes a solid objection.

    I was wondering if you brought it up seriously or humorously.

    here is the full quote and the reference [14] to Horowitz Maldacena paper:

    ---quote---
    Finally, we have learned some things about black holes over the last decade that even Stephen Hawking agrees with [13]. Black holes do not lose information. The implication [14] is that if there is any kind of universe creation in the interior of the black hole, the quantum state of the offspring is completely unique and can have no memory of the initial state. That would preclude the kind of slow mutation rate envisioned by Smolin.

    [14] G. T. Horowitz and J. Maldacena, The black hole final state,” JHEP 0402, 008 (2004) [arXiv:hep-th/0310281].
    ---end quote---

    the paper he cites by Horowitz Maldacena is a proposal, not a proven result.
    ---quote hep-th/0310281 abstract---
    We propose that in quantum gravity one needs to impose a final state boundary condition at black hole singularities. This resolves the apparent contradiction between string theory and semiclassical arguments over whether black hole evaporation is unitary.
    ---end quote---

    They apparently assume there is a singularity. A boundary. It is just the LQG point that spacetime does not end, where there used to be the classical singularity. One does not need to impose a final state (as Horo and Malda believe necessary.)
    Their paper is speculative, they admit, and takes string theory (?) as point of departure

    ---quote from Horo and Malda conclusions---
    We have suggested a possible resolution of the apparent contradiction between string theory and semiclassical arguments over whether black hole evaporation is unitary. By imposing a final state boundary condition at the black hole singularity, one circumvents the usual causality problem and obtains unitary evolution even in a semiclassical treatment. The ideas in this paper are completely consistent with the ideas of Hartle and Hawking about a unique wavefunction for the universe [11]. It is precisely this uniqueness that saves the day in black hole evaporation. Notice that a unique initial quantum state does not imply a unique macroscopic state, we could have a superposition of different macrocopically distinct universes. Our proposal is clearly very speculative, and we have not given any constructive method for computing the black hole final state. In principle, this can be deduced from a precise calculation of the evolution |psi>_M arrow |psi>_out. Hopefully, we will soon discover some techniques to compute it!
    ---end quote---

    Susskind throwing this up as an objection does not encourage me to put much weight on his other arguments. Perhaps you see it differently.
    (unless you were just kidding.)
     
  18. Nov 14, 2004 #17
    All the evidence seems to give a strong indication that life emerges as soon as possible. Carbon production and second or third generation stars are indeed important processes, but I guess what I was saying was that in respect to the age of the universe, life and intelligent life has existed and evolved during a quarter of that time at best!

    I’m not merely looking at the number of stars and saying statistically speaking there’s been many chances, I’m looking at the evidence which seems to suggest that life emerges as soon as possible, whether its an integral part of the evolution of the universe.

    And because we don’t know how abundant life is in the universe, we ought to take seriously the idea that it may be a more crucial part than we’ve been led to believe.
     
  19. Nov 14, 2004 #18
    Here’s a 1998 interview with Dyson, not much in the way of molding the universe though, a lot of emphasis on patience and thinking in the long term however.

    CNS is still an interesting theory. Do you think it could be applied to other models such as Andrei Linde’s eternal inflation, or cyclic universes? I wasn’t saying I’d found anything that truly refuted the theory, Susskind and Hawking seemed to make a pretty strong case against the black hole universe theory, mainly on points regarding the merging of black holes, I forget what Smolin’s argument is, maybe two universes merging into one?
     
  20. Nov 14, 2004 #19

    turbo

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    Link added

    Here is a link to the EDGE exchange...it is about 3/4 of the way down the page.


    Correction!

    http://www.edge.org/

    Sorry about that - here is the link.
     
    Last edited: Nov 15, 2004
  21. Nov 15, 2004 #20

    Chronos

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    Turbo, I can't get the link to work...:biggrin:
     
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