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What Is In A Chance?

  1. Mar 10, 2004 #1
    Let's take a look at how evolution is fined tuned for life forms? When you consider carbon, element number six in the periodic table it must first become hydrogen, helium, lithium, beryllium, and boron. After it come nitrogen and oxygen and the rest of the ninety-two or so natural elements. Life as we know it is based on carbon. It is the only element that can form the long and complex chains necessary for the process of life itself. Elsewhere in the universe any life form may be based on liquids other than water, but carbon is the necessary elemental jack-of-all-trades for life. It is also the essential Lego-like stepping stone for the production of eighty-six natural elements heavier than carbon.

    But the formation of carbon sits on a knife edge of uncertainty. To form carbon, radioactive beryllium (element number 4) must absorb a nucleus of helium (element number 2) and build to element number 6 (carbon). Doesn’t that seem simple enough: 4 + 2 = 6. Who said physics is difficult. However beryllium does not have much of an existence. The mean life of this radioactive beryllium atom is 10 16 seconds.

    I got the feeling of the brevity of 1016 seconds, I looked at that number in decimal numbers or 0.00000000000000001 seconds. In that sliver of time, one little ole helium nucleus must find, collide with, and be absorbed by the beryllium nucleus, thus metamorphosing into the atomic staff of life.

    It seems that the only way the helium nucleus decays is if the energies of these nuclei are matched exactly to the required energies of excitation. And matched they are. Carbon is the fourth most abundant element that is solid at temperatures when water is liquid. If this reaction were foiled by mismatch, the universe would contain hydrogen and helium and not much of anything else. The elements of our life would not have formed.

    It is probable that all of these events could have simply happened with enough time and by random events. These discoveries of science provide a quantifiable basis for that awe. I admit that this universe in which we live is a very special chance happening.
     
    Last edited: Mar 10, 2004
  2. jcsd
  3. Mar 12, 2004 #2
    "Carbon has four symmetric valences that facilitate the assembly of long-chain compounds. Simple carbon chain compounds can build spontaneously into enzymes and replicating devices such as RNA. And simple proteins are formed from primordial amino acids. These contribute to the production of more carbon compounds and replicating machinery. Thus DNA evolves. Out of the variety of such long-chain compounds come things like membrane. Sheets of conjoined, adherent molecules form membranes, asymmetric on the two sides. By surface tension, these form readily into spherules, presenting barriers which favor differential transport of substances into and out of the spherules. The replicating machinery of DNA, RNA and enzymes is relatively protected within the spherules. This suggests the beginning of cells. The machinery that can replicate the whole aggregate, by replicating the machinery itself and the spherule, is favoured over less competent systems for survival and continuing replication. The operation of this selection process means that evolution is off and running!"
    ?
     
    Last edited: Mar 12, 2004
  4. Mar 14, 2004 #3
    Hello Polly

    Originally posted by Polly

    "Carbon has four symmetric valences that facilitate the assembly of long-chain compounds. Simple carbon chain compounds can build spontaneously into enzymes and replicating devices such as RNA. And simple proteins are formed from primordial amino acids. These contribute to the production of more carbon compounds and replicating machinery. Thus DNA evolves. Out of the variety of such long-chain compounds come things like membrane. Sheets of conjoined, adherent molecules form membranes, asymmetric on the two sides. By surface tension, these form readily into spherules, presenting barriers which favor differential transport of substances into and out of the spherules. The replicating machinery of DNA, RNA and enzymes is relatively protected within the spherules. This suggests the beginning of cells. The machinery that can replicate the whole aggregate, by replicating the machinery itself and the spherule, is favoured over less competent systems for survival and continuing replication. The operation of this selection process means that evolution is off and running!"
    ?


    Yes Polly, the element carbon does have four symetric valences. Which is needed as the basic building block of all life forms. A carbon atom is first connected to a single bond, so it has three remaining open valences.

    But the point I was trying to make is the chances of carbon atoms forming in the first place. The implications of carbon forming from a radioactive beryllium nucleus which lasts for about 10 16 part of one second which must unite with a helium nucleus, with both nuclei at the same state of excitation, the formation of the element carbon itself is so statistically improbable as to be less than zero. Remeber we are not talking about one carbon atom, we are talking about this impossible reaction happening so often as to be the fourth most common element in the universe.

    For the remaining formation of carbon into long chains of reactions and interactions into a cell, you must first have carbon.

    You can't start out in the middle of a universe without explaining to me how this element 'carbon' came about by chance.
     
    Last edited: Mar 14, 2004
  5. Mar 14, 2004 #4

    selfAdjoint

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    But the point I was trying to make is the chances of carbon atoms forming in the first place. The implications of carbon forming from a radioactive beryllium nucleus which lasts for about 10 16 part of one second which must unite with a helium nucleus, with both nuclei at the same state of excitation, the formation of the element carbon itself is so statistically improbable as to be less than zero. Remeber we are not talking about one carbon atom, we are talking about this impossible reaction happening so often as to be the fourth most common element in the universe.

    And both of them in the heart of a supernova. That is in a VERY STRONG gravity field. And what do we know about time, and therefore the lifetimes of particles, in a strong gravity field?
     
  6. Mar 16, 2004 #5
    Originally posted by selfAdjoint

    And both of them in the heart of a supernova. That is in a VERY STRONG gravity field. And what do we know about time, and therefore the lifetimes of particles, in a strong gravity field?

    So let me get your premise correctly. A supernova or massive exploding star produces a 'very strong gravitational field?'

    A dying star expands to many times it size as the star uses up its long accumulated fuel. The star then explodes outward releasing its constituents that make up the elements which create new stars and galaxies. Sorry but any increase in gravitation would pull the exploding matter inward which sometimes happens into such a small condensed core that a so-called black hole forms where everything in the area is pulled in to the center core including photons and from which is believed nothing is released. There is thought to be a function in black holes called a 'singularity' where the gravity is so great that time itself is no more.

    I don't believe that Carbon is one of the elements formed in supernova or in black holes from which nothing is said to escape.

    As you say, time is relative depending on velocity and gravity according to Einstein's theory. I still can't see how the element carbon is formed in Supernova.
     
  7. Mar 16, 2004 #6

    selfAdjoint

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    There is no increase in gravitation. Before the star explodes it still has its original mass, and the gravity is still massive at its center, and lifetimes of particles are extended.
     
  8. Mar 17, 2004 #7
    Originally posted by selfAdjoint

    There is no increase in gravitation. Before the star explodes it still has its original mass, and the gravity is still massive at its center, and lifetimes of particles are extended.

    Are you saying that massive stars, dying or not, have gravity sufficient enough to slow time enough to extend the radioactive beryllium's lifetime and at the same nucleus state of excitability as a helium nucleus?

    Local time even at high gravity is slow relative to other places with less gravity. Nothing to diminish the possibility for the formation of the element carbon.
     
  9. Mar 17, 2004 #8
    Talus,

    I enjoyed your post -- which I found to echo the Anthropic Principle (i.e. if the universe were not precisely as it is -- if Boltzmann's constant, the gravitational constant, the cosmological constant, Planck's constant, the strong and weak force constants, the rest masses of each particle, the speed of light, etc. were only slightly different than how they actually are -- then we would simply not be here.)

    I just wanted to (respectfully) point out my disagreement with one of your statements.

    You said, Life as we know it is based on carbon. It is the only element that can form the long and complex chains necessary for the process of life itself.

    The first sentence is correct, but the second is not (in my opinion, that is).
    I don't think you can conclusively exclude silicone (or, for that matter, nitrogen/ phosphorus) as a basis for a complete biochemistry.

    Although there are some drawbacks to silicone (or nitrogen/ phosphorus) acting as carbon analogs, that might simply be a result of our carbon-centric perspective (in which we only know and understand a carbon-based biochemistry in our specific environment).
    In the appropriate exotic environment, any speculative exobiology has to consider the possibility of these two alternatives.

    silicone
    Regarding silicone, although the silicone analog of the alkane hydrocarbons (i.e. silanes) decompose spontaneously at long chain lengths, that's only because they're highly reactive with H2O. In the correct (non-water-based) environment, it's theoretically possible to have silicone-based life -- in such environments, the Si-O-Si bond is is even more stable than the Si-Si bond.

    nitrogen/phosphorus
    For nitrogen/ phosphorus, the formation of complex macromolecules is completely possible -- insofar as phosphorus can spontaneously form long stable chains (that is, with the P-N bond, since phosphorus alone is highly reactive). Like carbon, there's a wide range of possible P-N structures (including rings, that we see so much of in Earth's biology).

    hypothetical examples
    The key thing to keep in mind is that it is very dependent on the specific environment in which the prospective life is to occur. For example, on Earth, where the atmosphere is 80% nitrogen, a P-N life-form wouldn't make sense, since N2 is so inert and the only life-forms here that can "fix" molecular nitrogen are plants that use symbiotic anaerobic bacteria.

    But in an atmosphere made of NO2 (nitrogen dioxide) or N3 (ammonia), it becomes less "energetically-expensive" to fix nitrogen (since it forms a number of oxides with oxygen -- N2O, N2O4, etc.) In such an environment, you could have P-N "plants" taking nitrogen dioxide from the atmosphere and phosphorus from the ground. They reduce the NO2 to P-N "sugars", then release oxygen as metabolic waste. Animals (P-N based) consume these plants, then metabolize the P-N "sugars", and exhale nitrogen-dioxide into the atmosphere, and depost phosphorus waste into the ground... thereby completing the P-N metabolic cycle.

    You could formulate the same cycle with a hypothetical ammonia-based atmosphere (the opposite pattern of oxidation/ reduction occurs from the NO2 example above... and hydrogen replaces nitrogen dioxide; also methane would take the role that CO2 has here on Earth).

    Conclusion
    I completely agree with you that carbon makes the most sense, and is probably the likely candidate for the biochemical basis for any exobiology. The fact that carbon is formed preferentially in stellar nuclear fusion means that it is by far more abundant in the universe than Si or P-N. My point is simply that (in principle) you cannot rule out these other (hypothetical) alternatives.

    Anyway, thanks again for the interesting post.


    Best regards,
    metasystem
     
  10. Mar 17, 2004 #9
    Originally posted by metasystem
    metasystem:

    I as well enjoyed your stimulating observations of other possible life forms which might be based on other than the element carbon. But it might be more helpful to determine the fundamental definition of the nature of life itself. Would you say that duplication is life when inanimate objects like crystals form new crystals? Are the functions of secretion, excretion, movement, conscious awareness the definition of life?

    It seems that no fossil life forms have been found on earth prior to the presence of H2O in more than 100 years of archeologists digging around the world. There is absolutely no way of postulating of life based on non-carbon life forms until we actually find such an entity. But exactly what is LIFE?

    Conclusion
    I completely agree with you that carbon makes the most sense, and is probably the likely candidate for the biochemical basis for any exobiology. The fact that carbon is formed preferentially in stellar nuclear fusion means that it is by far more abundant in the universe than Si or P-N. My point is simply that (in principle) you cannot rule out these other (hypothetical) alternatives.


    I believe that you are correct in your assumption that absolutely no alternatives can be eliminated in the formation of life. The reality that life exists on this little piece of star dust at the edge of this galaxy has the exact prerequisites for life itself. The irreducible complexity of each part of this process indicates to me that with only one nano difference in anything would result in a lifeless planet.

    It is interesting to speculate with our consciousness.

    Your servant,

    Talus
     
    Last edited: Mar 17, 2004
  11. Mar 17, 2004 #10
    I think (biologically) that it's easier to list the attributes of living things than it is to define what life is. Any comprehensive definition of life usually ends up leaving something out or inadvertently adding something in that has an empirical exception somewhere in nature. For example, if you define life as simply the ability to self-replicate, then you must consider (as you pointed out) crystals/ Madelbrot sets/ Wolfram's automata to be "alive", and you must also consider infertile couples to be "not alive".

    So I think it's more useful, albeit less philosophically satisfying, to simply list the attributes that living things have (I won't list them because one can simply look them up), but I will agree with you that there are certainly gray areas (for example, would a biochemically-inorganic artifical intelligence be considered to be "alive"? etc.)

    But if we want to satisfy some philosophical yearnings, what I find interesting is the notion that on our planet, intelligent life evolved from carbon, nitrogen, oxygen, phosphorus, sulfur, and hydrogen, coupled with solar energy. With the exception of hydrogen, all of this matter originated from the supernovae of a previous generation of stars in our region of the galaxy, and it came together during the formation of our solar system about 5 billion years ago.

    So really, it is not all that scientifically inaccurate to say that we are "born of stardust"... despite the poetic new-agey connotations of that phrase. In a sense then, we (humans) are really just another part of the physical universe, but a special part that has the capacity for self awareness.

    It's almost as if the universe found a way to "know" itself and contemplate its own beauty -- and that way is us.

    Best regards,
    metasystem
     
  12. Mar 18, 2004 #11
    Originally posted by metasystem

    I think (biologically) that it's easier to list the attributes of living things than it is to define what life is. Any comprehensive definition of life usually ends up leaving something out or inadvertently adding something in that has an empirical exception somewhere in nature. For example, if you define life as simply the ability to self-replicate, then you must consider (as you pointed out) crystals/ Madelbrot sets/ Wolfram's automata to be "alive", and you must also consider infertile couples to be "not alive".
    So I think it's more useful, albeit less philosophically satisfying, to simply list the attributes that living things have (I won't list them because one can simply look them up), but I will agree with you that there are certainly gray areas (for example, would a biochemically-inorganic artifical intelligence be considered to be "alive"? etc.)


    We have digressed from the negligible probability of the abundant creation of element carbon in the universe to an attempt to define the parameters of the definition of life. It seems that 'life' is nothing more than each individual's perception of existence. Like in Mary Shelly's Frankenstein, the good doctor ecstatically stated, "it’s alive." The concept was fictionalized in that inanimate organic material could be created to have all the biological functions of a living entity.

    But if we want to satisfy some philosophical yearnings, what I find interesting is the notion that on our planet, intelligent life evolved from carbon, nitrogen, oxygen, phosphorus, sulfur, and hydrogen, coupled with solar energy. With the exception of hydrogen, all of this matter originated from the supernovae of a previous generation of stars in our region of the galaxy, and it came together during the formation of our solar system about 5 billion years ago.

    With all due respect I must take exception to this notion. When we talk about life and cognition evolving from primary inorganic elements, over billions of years, this possibility has yet to be proven. It seems that evolution is no more than just one more theory until proven beyond circumstantial evidence. As with any theory, the proof comes when the process can be reproduced by multiple experiments which produces even the most elementary life form. I am not advocating an unseen power theory creating the process by which life came about even it was in the format of evolution. The fact remains to this day that all species of life forms on this planet did not appear until the Cambrian period as seen in fossil evidence coupled with the fact that no life form has been found to exist before water appeared on the surface of the earth.

    So really, it is not all that scientifically inaccurate to say that we are "born of stardust"... despite the poetic new-agey connotations of that phrase. In a sense then, we (humans) are really just another part of the physical universe, but a special part that has the capacity for self awareness.

    Sorry for the 'born of stardust' similitude. I find Bell's theorem interesting in the fact he implies 'separate parts' of the universe could be intimately connected at a deep and fundamental level. Bohm asserts that the most fundamental level is an unbroken wholeness which is, in his words, 'that-
    which-is.' All things, including space, time and matter are forms of that-which-is. The theory indicates that all particles in the universe are somehow connected to one another and 'aware' of each other by some innate wisdom of all particles. In the split screen experiments, it has been demonstrated that particles sometimes 'choose' to take the alternative slit in the screen. What is going on here in this existence of ours?

    Albert Einstein, Boris Podolsky, and Nathan Rosen published a scientific paper in 1935 that showed that, according to the mathematics of Quantum Mechanics, for other kinds of measurement, things didn't work out quite so neatly as previously expected. If one wanted to measure angular momentum, or spin, measuring angular momentum around one axis was complementary to measuring it around a perpendicular axis. It still took energy to measure angular momentum. But it was possible to measure the angular momentum of an object without contributing any angular momentum to it at all.

    Processes were known that result in two particles, with equal and opposite spins, being emitted in opposite directions. If one chooses an axis, and measure the spin of one of the particles relative to that axis, in order that no angular momentum is added or lost, when one shoehorns one particle into a state where it really is spinning, say, either up or down, the same thing must happen to the other particle, even though it may be far away!

    This phenomenon apparently has been demonstrated by multiple experimentation.

    It's almost as if the universe found a way to "know" itself and contemplate its own beauty -- and that way is us.

    What is the plausibility that the universe 'found a way' to "know" itself or to contemplate anything? Even that us which came about by any chance evolutionary route into this existence?

    Interesting contemplation of statistical probabilities having formed ex-nilo.

    Talus
     
    Last edited: Mar 18, 2004
  13. Mar 23, 2004 #12
    Talus,

    You are treating the concept of a "theory" as though it were a "hypothesis". In common usage, theory may mean this but in scientific usage it is quite the opposite (perhaps hypothesis is simply too cumbersome of a word for people to use on a casual basis). A theory is not an "educated guess". It must be supported by repeated and wide array of empirical evidence before it earns the status of theory. A theory is the end point of all knowledge - not the beginning. It is the highest level of certainty (although varies by theory according to strength). As such, this particular theory is highly supported by overwhelming evidence and cross verified by independant studies and vastly divergent fields of study which jive with one another. For whatever gaps are present due to practicality, there is simply no other competing theory which comes close to this great level of evidence and verification. It is not "just another theory" among many.
     
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