In 1953, an experiment was carried out on a laboratory that would soon gain worldwide notoriety, an experiment whose results have been repeated and confirmed many times over since then. Stanley Miller and Harold Urey took small amounts of four simple compounds, water, methane, ammonia and hydrogen, thought by them to represent the chemical compounds most abundant before the appearance of life on Earth, and put the mixture inside a clean flask. The mixture inside the sealed flask was zapped repeatedly with electrical discharges, and after seven days the flask had taken a thick reddish-brown color resembling blood, and was found to contain complex organic molecules such as carboxylic acids and aldehydes, including some of the basic building blocks of life, specifically alanine and glycine, two amino acids essential to living proteins. The enormous significance of this discovery is that for the very first time it was shown how the basic building blocks needed to create very primitive life forms could arise from natural processes alone. Indeed, the four simple compounds placed by Miller and Urey inside the flask before the zapping are compounds that are abundant not just here on Earth but elsewhere in the Universe. And it is not hard to imagine an environment where naturally occurring electrical storms can do a lot of zapping into such “primeval soup”. Furthermore, experiments carried out using heat sources instead of electrical discharges (duplicating the conditions that would have been produced by early volcanoes) provided similar results. It was later found that other mixtures of gases including carbon monoxide, carbon dioxide and nitrogen were equally useful provided that no oxygen was included as part of the mixture. As long as these conditions do occur (and the Universe appears to have been built in such a way as to allow these conditions to take place many times over not just here on Earth but beyond), it is inevitable that the building blocks of life will begin to appear sooner or later. The experiment thus resolved the enigma of how these basic building blocks of life could have arisen on Earth seemingly out of nowhere. However, the “grouping together” of these basic building blocks in the correct order needed to build even simple organisms such as bacteria and fungi is something else, and going from simple protozoa all the way up to a dinosaur or a pterodactyl in a matter of a few tens of millions of years is a completely different story. Several ingenious mechanisms at the molecular level (such as mutations and crossovers) have been proposed to explain the assembly process, and in order to speed up the process so as to make it possible for life to evolve in complexity in the short span of tens of millions of years instead of trillions of years (keeping in mind that the estimated age of the Universe does not exceed 15 billions years), science has resorted to its pièce de résistance in these matters: Darwin’s theory of evolution. One key ingredient to evolution is its strong reliance upon the power of large numbers in order to make seemingly impossible happenings an expected naturally occurring phenomenon. The argument is still the same as the one given by Lucretius two thousand years ago, although under a different guise: Given an “almost” infinite (very big) amount of “primeval random soup” ceaselessly combining and recombining during an “almost” infinite amount of time all the possibilities and configurations that are allowed under the laws of Nature will occur and recur without end. The Lucretian argument is very seductive, until one begins to honestly throw numbers into the picture in trying to obtain an estimate of the odds for primitive life forms to appear under such circumstances. And until recently the odds were truly dismal indeed. To begin with, on a planet of limited size such as Earth, even if all the oceans were filled to capacity with that “primeval random soup” instead of water, the amount of “random soup” would certainly fall far short of “almost infinite”. And the time frame available for the miracle to take place (less than a few tens of millions of years) also falls far short of “almost infinite”. Just as in the case seen on Chapter Two where trying to get a fast computer working randomly to spew out the simple phrase “THE HOUSE ON THE PRAIRE” was found to be almost a mathematical impossibility even on a time scale far exceeding the age of the universe many times over, trying to get correctly the genetic code of a very primitive virus consisting of a crude sequence of something like 10,000 units arranged in a very precise order could also be found to be even more mathematically impossible to occur (this is one reason of why biologists don’t like to get their hands dirty with the actual mathematical details of evolution). Somehow, in honest appraisals, the numbers would always come up short, and as usual the gimmick of large numbers quickly deflated, making the appearance of life on Earth not just a very improbable event but almost an impossible event. Clearly, something was amiss. One assumed key ingredient of all of the proposed combinations and recombinations of the basic building blocks of life was that they were supposed to take place as part of a linear process, in a fully deterministic and predictable manner. We must keep this in mind as we proceed forward.
It was held by Charles Darwin himself that the changes being accumulated selectively by each species came slowly, gradually, with very small increments taking place one small step at a time, under time spans extending over several geological eras (essentially, this is the description of a linear biological process). If we were to agree with Darwin, from what we know today those changes indeed would have to be spread far apart over vast periods of time. We still have records to this date from the time of the Roman Empire, more than two thousand years ago, describing many biological species discovered during those times by early explorers, and to this date all of those species retain exactly the same shape as they had before. We do not see any new species of sharks appearing in the ocean. We do not see any giraffes growing smaller or longer necks. We know from fossil records that a lot of species have been driven into extinction either by changing global climatic conditions or by predatory actions by Man, but nothing new has come across recently into this planet to replace them, as far as higher life forms are concerned. The world of higher life forms, the world most visible to us, is remarkably stable, and the only documented changes to date that we are witnessing within our lifetimes are taking place at the level of small microorganisms. It is towards the world of the very small, a world invisible to most of us, where we must turn our eyes in order to find support for Darwin’s theory of evolution. But if the changes on all life forms (especially upper life forms) have to come very, very slowly, then evolution comes into serious troubles when trying to reconcile such slow changes with the rather limited time lifespan of our Universe. [When Charles Darwin reached his conclusions, it was a widely held belief at the time that the Universe had existed "forever", that the clock could be run backwards indefinitely without ever reaching a stopping point. It should come to us as no surprise then that a limited supply of "time" was of no concern to Darwin, and evolution could thus "take its time" to carry out its act, there being a truly infinite amount of time at its disposal.] If anything, a growing body of evidence seems to point to an alternate theory that has come to be known as punctuated evolution. This revolutionary theory proposes that evolution does not move at an even “linear” rate one step at a time, but instead it moves at an uneven rate where there are long periods of time during which a species appears to be in very stable equilibrium, punctuated by periods of sudden rapid evolution. It is likely that this new theory would have shocked Darwin (and it still shocks many traditional evolutionists), for if true (and there’s a good chance it might be), this alternative would put the linear piecewise building model of Darwin into very serious trouble. The basic tenet, primitive life forms evolving into more advanced and complex life forms, is still preserved intact. However, the mechanism needed to bring about such process, the linear mechanism proposed by Darwin, can no longer be the sole main mechanism for any worthy evolutionary process.
As it turns out, trying to beat the dismal odds of probability and explain the possibility of punctuated evolution were perhaps the least of the problems being faced by “traditional” evolution.
Soon after Charles Darwin introduced evolutionary theory into the world, it met its fiercest foe, its sharpest detractor, and its strongest opponent. Though this may come as a surprise to some, we are not talking about creationists who basing their convictions upon the Bible’s Book of Genesis firmly believe that every biological species that has lived here on Earth was created independently. No, we are not talking about a direct assault launched by religious zealots against a scientific theory. Rather, it is a head-on frontal attack against a scientific theory coming from another field of science itself, fighting it out on nearly equal grounds. This most formidable opponent of them all is none other than the second law of thermodynamics.
In a way, creationists have resorted indirectly to the second law of thermodynamics by arguing, not without basis, that an extremely intricate structure such as an elephant or a shark cannot arise slowly and spontaneously out of nowhere, which would require each atom and molecule that make up the enormously complex organization of many living organisms to come together at precisely the right place at the right time without any prior planning and without any type of disturbance. We would never expect Nature to carve out a replica of a sculpture like Auguste Rodin’s Le Penseur from a tall mountain that is being worn down through the ages by snow, wind and rain. And a grown up elephant is a vastly more complex arrangement than any sculpture ever made by Man, so much so that even today with all the combined technological resources of Earth put together we would not be able to assemble within a reasonable time frame a simple amoeba atom-by-atom, much less an elephant. But the second law of thermodynamics, if applied in full rigor, goes even farther. According to it, the creation of order somewhere must always come at the expense of the destruction of order somewhere else, and once this has taken place the total amount of disorder will always outweigh whatever order could have been created, since it is the natural course of all things when taken as a whole to deteriorate and decay, not to build themselves from the ground up in open defiance of all known laws of probability. And when we are talking about living organisms, we are talking about the –almost unbelievable- spontaneous appearance of order out of chaos. True, from a fiery start in which life was surely absent, to the subsequent cooling down into a uniform chaotic hot gas, gravitation was able to pull the trick of condensing a lot of that primeval gas into the stars and galaxies we see in the sky. But even gravitation alone cannot bring together a wide diversity of atoms to build those highly ordered molecular structures we call living forms, not while having to contend at the same time with the second law of thermodynamics. Indeed, according to the second law of thermodynamics, we ourselves should not even exist. Any evolutionary process attempting to build us from scratch over a long period of time would be promptly wiped out by the merciless grip of this law, and all life as we know it not only becomes extremely improbable, it becomes impossible. Yet, here we are!
We are thus confronted by a seemingly irresolvable paradox. On one hand, we know nowadays that evolution is supported by a growing body of evidence and experimental data [The appearance into the scene of new strains of bacteria highly resistant to antibiotics, and the increasing adaptability of new viruses such as the AIDS virus to their environment, accomplished through clever mutations, can only by explained by an acceptance of evolution and natural selection as the driving forces responsible for the creation of these new life forms. It is unfortunate that the final proof required to close down the arguments between evolutionists and creationists is coming at such an enormously high price for mankind.] On the other hand, no physical process known to Man with the exception of life itself has ever been shown to contradict the second law of thermodynamics.
As tempting as it may be to give up in cases such as this one, faced with the challenge of trying to reconcile such opposing viewpoints sooner or later there will be someone who will take the challenge and come up with a solution nobody else before him had figured out. In this case, such a man was Ilya Prigogine, and his solution has come to be known to us as “dissipative structure”.
Before proceeding, we need to clarify the notion of “thermal equilibrium”. Imagine you have a bucket filled with very cold water near the freezing mark in one hand and a very hot red-glowing iron rod in the other. If you dip the hot iron rod into the bucket of cold water, the cold water will warm up and the hot iron rod will cool down until they both have the same temperature. Energy has flowed from the hot iron rod into the bucket of cold water to warm it up, and as a result of giving up that energy the iron rod cools down. No energy has been destroyed in the process, and the total energy remains the same, in accordance with the first law of thermodynamics. When both the iron rod and the water in the bucket have reached the same temperature, they are in a state of equilibrium; thermal equilibrium, that is. Energy can no longer keep flowing from the iron rod into the water since they both have the same temperature. If such a thing were to happen, the water would begin to warm up and the iron rod would begin to cool down even further, and the temperature difference between the two would grow wider (in the opposite direction) instead of smaller. As long as the total energy content remains the same, there is nothing in the first law of thermodynamics that forbids this from happening. But we never see this happening, and we would be very much amazed if such a thing occurred. This is because the second law of thermodynamics completely rules out this possibility. Once a system has reached a state of thermal equilibrium, the only way in which it can be restored back to its original configuration is by work done on the system with that work coming from an outside source. When the original system was not yet in thermal equilibrium, before the hot iron rod was dipped into the bucket of cold water, the system had lower entropy. But once the system reached thermal equilibrium, its entropy increased. By using an outside source to restore the system back to its original configuration, i.e. to lower again the entropy of the system, the entropy of the outside source will have to increase, and if the process of dipping again the hot rod into a bucket of cold water with the outside source restoring the original configuration over and over again is repeated indefinitely, it is likely that sooner or later the bucket of water, the iron rod and the outside source will all reach a state of thermal equilibrium, with all three settling down at the same final temperature. No further action can be extracted from here. In effect, it is as if they had reached a state of thermal death. Frightening as it may sound to many, unless there is some new important natural law we have not yet discovered that will overcome the second law of thermodynamics, the entire Universe is heading towards its own final state of thermal equilibrium, its thermal death [among the first ones who were able to foresee this outcome was the German scientist Rudolf Clausius].
Since a state of thermal equilibrium is, for all practical purposes, of interest mainly to a mortician or an archaeologist, when we study natural phenomena we like to focus on states that have not yet reached full thermal equilibrium. Of interest to many researchers are states near thermal equilibrium (as opposed to states far away from thermal equilibrium) since in many cases they can be modeled by sets of linear equations. Linear equations have several distinct advantages. One of them is that they can be manipulated and solved without a lot of mathematical complications. Another advantage is that they can be used to make rather precise predictions about the outcome of many experiments. If the phenomenon that is being studied happens to be by its very nature nonlinear, then the first order of business is to try to linearize its behavior near a point of interest (and in many cases the point of interest is very close to the point of equilibrium of the system). Nonlinear phenomena sometimes present behavior that is downright bizarre. In a linear progression such as the following:
5, 10, 15, 20, 25, …
coming from a given mathematical model, the reader would have no problems in predicting (and expecting) the next four terms to be 30, 35, 40 and 45. But in a nonlinear progression coming from another mathematical model, if the first terms are
3, 6, 9, 12, 15, …
then the next four terms, instead of being 18, 21, 24 and 27, could very well be something like 30, 10, 1 and 400, in that order. It must be kept in mind that a sequence such as this one, if produced by a nonlinear mathematical procedure, is not a random sequence. Indeed, if we start out again with the above same five numbers and the same nonlinear rule for generating them, then we will always obtain the same sequence that follows in a fully predictable manner, whereas a wholly random process will most likely yield an entirely different sequence each time it is run (in a random process, even the first five terms will be different every time the process runs). This is typical of chaotic phenomena as opposed to random phenomena: they are fully predictable in principle, yet their outcome is unpredictable or, to use a better expression, unexpected. When dealing with nonlinear phenomena, researchers have come to expect the unexpected, and it is precisely in this realm where the modern science of chaos has originated.
Writing an article entitled Thermodynamics of Evolution for the November 1972 issue of Physics Today, Ilya Prigogine and his collaborators state:
“The physicochemical basis of biological order is a puzzling problem that has occupied whole generations of biologists and physicists and has given rise, in the past, to passionate discussions. Biological systems are highly complex and ordered objects. It is generally accepted that the present order reflects structures acquired during a long evolution. Moreover, the maintenance of order in actual living systems requires a great number of metabolic and synthetic reactions as well as the existence of complex mechanisms controlling the rate and the timing of the various processes. All these features bring the scientist a wealth of new problems. In the first place one has systems that have evolved spontaneously to extremely organized and complex forms. On the other hand metabolism, synthesis and regulation imply a highly heterogeneous distribution of matter inside the cell through chemical reactions and active transport … In contrast to this is the familiar idea that the evolution of a physicochemical system leads to an equilibrium state of maximum disorder. In an isolated system, which cannot exchange energy and matter with the surroundings, this tendency is expressed in terms of a function of the macroscopic state of the system: the entropy. It amounts to saying that entropy S increases monotonically until it becomes a maximum. This celebrated second law of thermodynamics implies that in an isolated system the formation of ordered structures is ruled out … The probability that at ordinary temperatures a macroscopic number of molecules is assembled to give rise to the highly ordered structures and to the coordinated functions characterizing living systems is vanishingly small. The idea of spontaneous genesis of life in its present form is therefore highly improbable, even on the scale of the billions of years during which prebiotic evolution occurred. The conclusion to be drawn from this analysis is that the apparent contradiction between biological order and the laws of physics –in particular the second law of thermodynamics- cannot be resolved as long as we try to understand living systems by the methods of the familiar equilibrium statistical mechanics and equally familiar thermodynamics.”
When studying systems near thermal equilibrium, the outcomes become pretty much predictable. And in such environments, the odds of complex patterns and structures arising spontaneously are practically nonexistent. Yet, this was the background upon which the possibility of the appearance of complex organisms was being studied, a background that led nowhere.
The real breakthrough came when Ilya Prigogine decided it was time to abandon the linear world and start looking for answers in another field, the field of nonequilibrium thermodynamics. His efforts were rewarded, for he eventually made a major discovery. Previously, it had always been taken for granted that all chemical reactions tend to move in a direction which will produce a system in chemical equilibrium, and on the way nothing else will emerge from the random soup in which the chemical reaction takes place; no periodic phenomena, no signs of any visible type of order emerging, no complex structures, nothing. However, Prigogine and his collaborators found out that ordered systems could be stable far from chemical equilibrium, so far that the usual laws of equilibrium thermodynamics and near-equilibrium thermodynamics did no longer apply. Indeed, it is possible for stable states to exist that are spontaneously built up from fluctuations and are maintained by a flow of energy and matter from outside of the system. These stable states were given the name dissipative structures. Close to equilibrium, the fluctuations that give rise to dissipative structures tend to decay rapidly and therefore do not grow into stable ordered structures. The second law of thermodynamics still applies as a whole, since the spontaneous formation of dissipative structures and their survival depends upon a constant supply of matter and energy from outside the system, and this constant supply has a price tag that must be paid by an ever rising entropy (or disorder) from wherever it is coming from, and thus the total entropy of the universe keeps on rising. In the article already cited, let’s us see how Prigogine and his collaborators themselves describe these concepts:
“The destruction of order always prevails in the neighborhood of thermodynamic equilibrium. In contrast, creation of order may occur far from equilibrium and with specific nonlinear kinetic laws, beyond the domain of stability of the states that have the usual thermodynamic disorder … in chemical kinetics nonlinearity may arise in a practically unlimited number of ways through autocatalysis, cross-catalysis, activation, inhibition, and so on … In all these phenomena, a new ordering mechanism, not reducible to the equilibrium principle, appears. For reasons to be explained later, we shall refer to this principle as order through fluctuations. The structures are created by the continuous flow of energy and matter from the outside world; their maintenance requires a critical distance from equilibrium, that is, a minimum level of dissipation. For all these reasons we have called them dissipative structures.”
The concept of dissipative structures has other applications besides giving the origin of life a plausible explanation most scientists can live with. It has also been applied to problems in biology, meteorology, chemistry, fluid dynamics, economics and sociology. We must never loose sight of the fact that dissipative structures owe their very existence to nonlinear processes. John Briggs and F. David Peat state the following about nonlinearity in their book Turbulent Mirror:
“Nonlinear equations are like a mathematical version of the twilight zone. Solvers making their way through an apparently normal mathematical landscape can suddenly find themselves in an alternate reality. In a nonlinear equation a small change in one variable can have a disproportional, even catastrophic impact on other variables. Where correlations between the elements of an evolving system remain relatively constant for a large range of values, at some critical point they split up and the equation describing the system rockets into a new behavior. Values that were quite close together soar apart. In linear equations, the solution of one equation allows the solver to generalize to other solutions; this isn’t the case with nonlinear equations. Though they show certain universal qualities, nonlinear solutions tend to be stubbornly individual and peculiar. Unlike the smooth curves made by students plotting linear equations in high school math classes, plots of nonlinear equations show breaks, loops, recursions –all kinds of turbulence. In the nonlinear world –which includes most of our real world- exact prediction is both practically and theoretically impossible. Nonlinearity has dashed the reductionist dream. [The reductionist philosophy of modern science attempts to reduce complex phenomena to simple explanations. Only until recently it has been recognized that some natural phenomena cannot possibly be understood by reducing it to more elementary constituents. The modern science of chaos provides many examples of this. Benoit Mandelbrot's fractal geometry provides many other examples. Not even mathematics has been spared, for with Kurt Gödel's incompleteness theorem we have the full assurance that the truthfulness of many mathematical propositions cannot be formally proven nor disproved, and we have the unpleasant choice of assuming they may be true though they very well may be false, or vice versa. This inability to try to find simple explanations for everything has given rise to new approaches such as holism where it is assumed that the whole may be greater than the sum of its parts.”]
Inside a chemical reaction where nonlinearity is hard at work, dissipative structures can exhibit unusual behavior that does not resemble anything we would expect from a mixture of reagents trying to settle down toward a state of stable equilibrium. They may exhibit a “primitive memory effect” that makes them capable of storing information accumulated from a remote past, they may show some capability for propagating information over macroscopic distances by means of chemical signals, or they may even break into spontaneous self-sustaining oscillations that can be observed visually in a laboratory. To support his theory, Prigogine resorts to experimental evidence found in the chemical laboratory that shows that, assuming the right conditions are in place for the experiment, dissipative structures can be created at will, specifically the Belousov-Zhabotinsky reaction. This reaction, which is quite something to look at while it takes place within the confines of a petri dish, requiring a brew of malonic acid, bromate and cerium ions mixed in sulfuric acid, starts out with an initially random chaotic motion of molecules in a solution. Due to the nonlinear character of the chemical reactions taking place, the slightest fluctuation in one part of the solution can become magnified (this is precisely what Prigogine refers to when he uses the term order through fluctuations). If there is a “chance” concentration of a small quantity of “blue” molecules in one region of the petri dish –and this will usually happen precisely because in the initial solution all of the molecules are moving at random rather than staying out spread uniformly in the same place- then these “blue” molecules will act as an aid to assist in the production of more “blue” molecules –the technical term for this helping process is catalysis- which in turn will assist in the production of even more “blue” molecules. The process continues to grow exponentially allowing the “blue” molecules to build up in one region while at the same time the “red” molecules will prevail in a nearby region, until an increasingly intricate pattern begins to show up on the petri dish. This order originating in a microscopic fluctuation emerges and eventually takes over the random chaos of the original solution, and it is kept on going by the energy that is being constantly furnished by the chemical reaction. Let us hear from Prigogine himself in Chapter 13 (“Self-organization in Chemical Reactions”) of his book Self-Organization in Nonequilibrium Systems: From Dissipative Structures to Order through Fluctuations:
“The rate of chemical reactions is generally a nonlinear function of the variables involved (e.g. concentration or temperature). As the result, a chemically reacting mixture is described by nonlinear equations having, in general, more than one solution … Belousov (1958) reported a second case of an oscillatory chemical reaction in homogeneous solution, specifically, the oxidation of citric acid by potassium bromate catalyzed by the ceric-cerous ion couple. Zhabotinski (1964) pursued the study of the reaction and demonstrated that the cerium catalyst could be replaced by manganese or ferroin and that the citric acid reducing agent could be replaced by a variety of organic compounds, either possessing a methylene group or easily forming such a group during oxidation (e.g. malonic or bromo-malonic acid) … When the reaction occurs in a well-stirred medium, sustained oscillations in the chemical concentrations appear for certain ranges of initial composition of the mixture … Eventually the oscillations die out, as the system remains closed to mass transfer and the raw materials for the reaction are exhausted … Finally, when the reaction takes place in an unstirred shallow layer (e.g. in a petri dish) or in a visual container, various forms of wavelike activity are observed … In the thin layer the most common ones are concentration waves with cylindrical symmetry or rotating spiral waves … The reaction remains oscillatory everywhere in space except along the axis … We have, therefore, a striking experimental illustration of a spatiotemporal dissipative structure.”
The reader, assuming he/she has the required resources at hand, can duplicate in any high school laboratory some of the many interesting phenomena that occur when a chemical reaction like the Belousov-Zhabotinsky reaction happens to take place sufficiently far away from chemical equilibrium. For those interested in following this up, the recipe will now be given for an experiment that is both visually fascinating and instructive [the credit for the recipe of this experiment should be given to Dr. Alan M. Schwartz, Senior Research Scientist at Pharmacia Intermedics Ophthalmics].
First, the reagents required for the experiment are the following:
250 mL. of distilled or deionized water (reaction is poisoned by chloride).
25 mL. of concentrated sulfuric acid.
1 gr. of ceric sulfate powder.
1.5 gr. of potassium bromate.
3 gr. of malonic acid.
4 mL. of standard Ferroin solution (ferrous phenanthroline sulfate).
The procedure for the experiment goes as follows:
Pour the distilled water into a 400 mL. beaker. While constantly stirring, slowly pour the concentrated sulfuric acid into the beaker containing the water (this has to be done with care). Slowly add the ceric sulfate and potassium bromate to the warm aqueous sulfuric acid and stir until all solids have dissolved. Add the malonic acid and stir until the solution is complete. After this, slowly add the standard Ferroin solution.
After about one minute, the color of the solution will begin to oscillate between red and green as the chemical reaction tries unsuccessfully to reach a state of equilibrium. Thus, a chemical reaction sufficiently far from equilibrium may not behave according to classical thermodynamic theory, but may oscillate without stopping much in the manner of the Belousov-Zhabotinsky or the Briggs-Rauscher reactions. And this is not something that may take place. Quite the contrary, it will always take place, assuming we have gathered together all the required initial conditions for the phenomenon to manifest itself. In our color-shifting experiment, if just one of the chemical reagents is absent, the phenomenon will not take place even if we sit down “till forever” waiting for it to happen. Thus, we must assume that all the required initial conditions are there to begin with. However, once the process has begun, the initial conditions may very well become unreachable, in yet another manifestation of the enormous power of the second law of thermodynamics. Quoting again from the book Turbulent Mirror, John Briggs and F. David Peat add their following observations in relation to Prigogine’s work:
“Once any complex system appears, Prigogine says, it becomes separated from reversible time by what he calls an ‘infinite entropy barrier.’ Processes that run in the reversed time direction become not just astronomically improbable, as (Ludwig) Boltzmann had said, but infinitely improbable. This can be illustrated by thinking about the ripples spreading out from a stone thrown into a pond. To time-reverse this situation would require coordinating precisely all the infinitesimal disturbances around the edge of the pond so that they move inward, growing in amplitude and finally converging at a simple dimple … Any ultimate coordinating of events around the pond is made impossible by the fact that all systems are open to the rest of the universe. Nature is bathed in a constant flux of gravity, electricity and magnetism in addition to small fluctuations in temperature and other forces. Even the movement of distant stars will produce minute changes in the gravitational field experienced on earth. While these fluctuations will be beyond any hope of measurement on earth, nevertheless they will always destroy initial correlations. So even if the correct initial conditions could be set up around the edge of the pond, they would be rapidly obliterated by such subtle contingencies long before contracting ripples converged on the center. In ideal, isolated systems time may be reversible but in real systems the symmetry of time is always broken”
Prigogine’s thesis, carried to the extreme, to the very realm of life, provides a way out in the resolution of the apparent contradiction between the second law of thermodynamics and evolution, making it possible for the most complex of all dissipative structures, living organisms, to appear on the surface of the Earth in spite of the overwhelming odds against such a thing from happening. Can the argument be carried out still further? In every instance we have made too many assumptions, taking for granted that all the required initial conditions will be there to begin with, handed to us from out of nowhere. This may be asking for too much. Nowhere do we see inscribed as an absolute law that all the initial conditions must be there at a certain time and place in order to enable such a thing as nonequilibrium thermodynamics to work its wonders. Yet as we peek towards the planets of our own solar system with more powerful space probes, and as we peek deeper outside into the cosmos, a growing body of evidence provides more than enough reasons to believe that the nonequilibrium thermodynamics required to bring living organisms into the universe may not be the exception but rather the rule. One thing we can be absolutely sure of is that, given the right conditions, such as those found right here on Earth, and allowing nonlinear processes to operate for an extended period of time, life will emerge sooner or later in other places inside this vast Universe of ours, as surely as the planets of our Solar system orbit around the Sun and as surely as the Earth rotates around its axis. Assuming otherwise would require us to believe that we have some exclusive universal patent granted to us for the sole possession of nonlinear processes and crucial chemical elements (such as carbon and oxygen) that should only be found here on Earth and nowhere else. The astronomical data we have at hand is more than enough to dispel this as mere wishful thinking. The discovery of the role played by nonlinear processes in the formation of complex life forms has raised enormously the possibility of finding life elsewhere in the Universe. But, in the final analysis, the full merit for the creation of evolving life forms must go to the initial conditions that have prepared the scenario, much as the merit of a masterpiece such as Hamlet must go to the man who wrote it instead of the actors who have played out the drama after it was written (no offense intended for the many fine actors who at one time or another have staged this drama).
We must now stress the fact that the basic building blocks of life that Stanley Miller and Harold Urey were able to produce in the laboratory have also recently been found in rather abundant quantities in interstellar dust clouds and even in meteorite samples. Thus the Universe appears to have a contingency plan to make these basic building blocks available one way or the other, either by having been produced right here on planet Earth or produced outside in the cosmos to be delivered later to our planet. In his book The Creation of Life, Andrew Scott states the following:
“In its day, the Miller experiment was significant and important, because it was the first to tell us that the basic chemicals of life may form with unexpected ease. But now that we suspect these same chemicals may be common throughout the Universe, and since subsequent simulations have failed to get us much further towards living things, the significance of the Miller experiment needs to be reassessed. I suggest that Miller’s and all later simulations might have been much more significant if they had failed to yield any of the simple chemicals from which we are all made. If it had proved completely impossible to re-create the formation of any of life’s simple building-blocks under primordial conditions, despite many years of trying, then that really would have been a dramatic discovery. It would have suggested that life could not have originated in this planet.”
With hindsight, knowing the ease with which the basic building blocks of life can be created in abundance in the Universe, added to the powerful sorcery that nonlinearity can exercise upon those basic building blocks to propel complexity out of chaos, then life instead of being a rare oddity was in fact an anticipated event, a miracle waiting to happen.
Having recognized that nonlinearity is the powerful trick that will foster the appearance of life and allow it to evolve into more complex forms, we must now come to grips with the fact that this new knowledge has come with a high price tag. In the “old-style” linear evolutionary process proposed by Darwin, one small step at a time, a gradual buildup in principle could be followed step-by-step, although the mathematical odds against such a thing from happening were found to be a major obstacle that traditional evolutionary theory was never able to overcome. Accepting the fact that nonlinearity may be the only way out of the conundrum deprives us almost immediately of our powers to analyze and predict the startup and subsequent evolution of any kind of life forms, for the very trademark of nonlinear scenarios is that they are wholly unpredictable under any conventional methods.
The current lack of adequate mathematical tools to try to study and categorize nonlinear phenomena does not mean that we are totally deprived of resources to discover analogies to the nonlinear events that occur in Nature. In the preface to his book Theory and Applications of Cellular Automata, Stephen Wolfram makes the following observations:
“The understanding of complexity and its origins is a fundamental challenge for modern science. Research in physics, biology and other fields has been immensely successful in finding the basic components of most of the systems of everyday experience. What must now be done is to discover how large numbers of these components, often each quite simple, can act together to produce the complex behavior that is seen. Science has traditionally concentrated on analyzing systems by breaking them down into simple constituent parts. A new form of science is now developing which addresses the problem of how those parts act together to produce the complexity of the whole. Fundamental to the approach is the investigation of models which are as simple as possible in construction, yet capture the essential mathematical features necessary to reproduce the complexity that is seen. Cellular automata provide probably the best examples of such models. Their basic construction is very simple. Yet their overall behaviour is found to be highly complex, and can reproduce the complex phenomena observed in many physical and other systems.”
Yep, it is cellular automata such as the game of Life that provide us with a chance to create new nonlinear universes, with each universe operating under its own rules, the rules that we as the creators decide to use. That a cellular automaton like the game of Life is inherently nonlinear can be verified with rather simple arguments. In the game of Life, the state any given cell will have on the next future generation (call it the second generation) will depend upon the current state of all its neighbors (in the first generation), and likewise its current state will also be a decisive factor in determining the next state of each of its neighbors. But once we have moved from one generation to the next (from the first generation to the second), after the fate of the cell has been determined by the previous value of each of its neighbors and the cell has had a chance to influence the value of its neighbors, when we go to the next succeeding generation (the third generation) the cell will have another chance to influence the value of its neighbors reflecting back upon them their combined influence exerted on the cell during the past generation. The situation is akin to a fighter angrily striking back hard at his opponent in retaliation for previously being angrily struck hard by his opponent who perhaps was only responding angrily for being struck hard in the first place; in which case the first blow provoked as response an angry second blow which in turned provoked as response an angrier third blow and so on ad infinitum (or until one of the fighters passes out). This is nothing less than what is commonly known as feedback, except that in the case of cellular automata the word used is recursiveness (we use the word “feedback” when dealing with continuous systems such as the microphone picking continuously the sound from the nearby speaker which goes again into the microphone and comes out amplified from the speaker just to go again into the microphone for further amplification and so on until the system breaks into a sharp piercing squeal; as opposed to the word “recursive” which is used with discrete systems such as cellular automata that go from one step to the next in a full jump with no “in-between” state). And it just so happens that recursiveness is the property in dealing with discrete mathematical models that gives rise to the phenomenon of nonlinearity.
Earlier before we had mentioned that the traditional evolutionary model proposed by Charles Darwin was powerless to account for the possibility of punctuated evolution. Interestingly enough, some cellular automata have been created and discovered recently that seem to display precisely that kind of behavior. The CEO of Thinking Machines, Danny Hills, created a program containing patterns he called “ramps”. The patterns were allowed to evolve, and evolutionary selection was based upon their capability to resolve a specific problem. Throughout the simulations, the computer kept a record of the fitness of the population as a function of time, and when the results were plotted on a graph it was shown that the graph displayed clear signs of punctuated evolution, with the fitness remaining nearly constant for a relatively long period of time and jumping all of the sudden to a higher plateau, with the process repeating itself in an unpredictable manner.
There is little reason to doubt that there exist many cellular automata capable of harboring patterns that will display obvious signs of evolution. But surely there are infinitely many others that will lead nowhere after a short while or that will end in one big mess (like completely chaotic patterns quickly degrading into oblivion). Nonlinearity is an extremely powerful tool in the design of new universes, in the design of alternate realities, but only if it is used wisely, very wisely.
By the same token, just by looking at our own Universe we can visualize immediately that there are many ways in which this Universe could have developed that would have made it impossible for life to appear anywhere. Just for the sake of argument, let us explore the possible outcome if the universal constant of gravitation G had been much less than its current value (if it had been much greater than its current value, all objects in the Universe would have gathered together rather quickly to create a “dark” universe filled with black holes instead of stars). In that case, the force of gravity would not have been enough to pull together the hydrogen atoms required to form stars, planets and galaxies, and all those atoms would be scattered around in an expanding universe, thinning out as an ordinary gas incapable of harboring any life forms, incapable of harnessing the enormous power of nonlinearity to bring about a much higher order of complexity into this Universe. Fortunately, by an extraordinarily lucky coincidence (?), the universal constant of gravitation has turned out to be just exactly the value required to form the solar system allowing nonlinearity to operate and bring about into this corner of the Universe nothing short of a miracle, the miracle of life.
Once we have agreed that the emergence of life in the Universe had to depend directly upon the necessary initial conditions required for this miracle to happen, initial conditions that preordained a nonlinear planet in a nonlinear Universe, initial conditions that in turn can be traced backwards in time not just to another set of prior initial conditions but to the very first initial conditions -and by this we mean the initial conditions that preceded the creation of the universe itself-, we are ready to turn the table around and discuss how our mere presence here on planet Earth poses severe limitations on those very first initial conditions, according to a principle known to cosmologists as the anthropic principle.
