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Out of Chaos “Light from darkness, order out of chaos” is a familiar and recurrent theme associated not only with Christianity but with many primitive mythologies as well. The Easter message of life arising out of death is an important instance; another is the Genesis account of creation, where the world is described as being created from out of the formless void. There is also a parallel in the scientific description of the evolution of the universe. Thermodynamics is the science of the flow of heat and energy in the numerous physical and chemical transformations which are taking place all the time. It owes its origins to the experience of weapons makers who noticed that when the bore of a cannon is reamed out, the metal becomes hot. The resulting insight, simple as it seems, was that the muscle power used by the worker, originating in the calories from his last meal, are converted into heat. Work and heat, then were seen as interconvertable. From this humble beginning arose the elegant science encapsulated in the three laws of thermodynamics. The first law simply states that energy cannot be created or destroyed; it can only be converted from one form to another. In other words, the total amount of energy in the universe is all there is; there will never be more and there will never be less. At first glance, that doesn’t seem to be so severe a limitation. On the other hand, it rules out what is known as perpetual motion of the first kind. It is inherently impossible, for example, to power a car without fuel or work a mule without food, in spite of the countless patent applications which claimed to have overcome this limitation. Strictly speaking, the first law is not universal; it does not hold up for extremely high-energy transformations such as are found in nuclear fission or fusion. Einstein has taught us that mass and energy can be converted into one another under suitable conditions. The first law, then, can be restated so that the sum of mass and energy cannot be created or destroyed. For everyday purposes, however, the first law is never violated. The third law is relatively specific and of no great interest here. It states that it is impossible to reach a temperature of absolute zero. The reason is that in order to cool any material, it is necessary to have an even colder material as a heat sink, and by definition there cannot be anything colder than absolute zero. The really interesting one is the second law, which in its simplest form, the dictum of ever-increasing entropy, requires some elaboration in order to make sense. Nonetheless, it is so fundamental a concept that it is at the heart of the crises involving both pollution and scarcity of resources. It also leads to some insights about the nature of evolution. There is a difference between energy and available or useful energy. The radiation from the sun which bathes the earth is a result of extremely high-energy fusion reactions converting hydrogen to helium. As it reaches the earth it is highly available, potentially capable of reaching high temperatures if appropriately harnessed. Most of it, however, is converted into moderate-temperature heat, warming the surface or evaporating water or the like. In the form of heat, it cannot be used to run a car or provide nutritional calories. To go back to the cannon-borers, muscle power can ream out the bore; a warm cannon cannot provide muscle power. This passage of energy from a relatively available to a relatively unavailable form is described by saying that entropy increases. Entropy can be thought of as a measure of the unavailability of energy. The second law applies to more than energy. In its broadest aspect, it says that useful work can be done only when energy can be allowed to flow from an available to an unavailable form. In other words, the process of extracting useful energy to do work results in the discharge of less useful energy, usually in the form of heat. One of the most pervasive applications is in substances spontaneously mixing together. Consider a swimming pool with filtered water. Beside it is a bucket of red dye. The pool and the bucket are in a state of low entropy. The dye could be used for various purposes, for example. Now dump the dye into the pool. The two substances quickly mix. The entropy has increased. It would take great effort to get the dye back into the bucket. The dye is no longer useful. Entropy in this sense is a measure of the disorder which nature seems to pursue relentlessly. Things wear down, mix together, come to the same temperature, and in so many other ways show increasing disorder. To restore a measure of order, it is necessary to do work, using up available energy. Another way of saying these things is to say nature continually converts order into chaos. What is a more recent insight is that nature is also capable of creating a new form of order out of the chaos. Much has been written about whether the evolutionary process so central to our understanding of the universe is in fact contrary to the second law. The conventional reductionist response is that whenever entropy seems to be decreasing locally (order is increasing), consideration of the full system will show that elsewhere there is a compensating increase in entropy, exactly as required by the second law. Modern chaos theory says otherwise. Again and again, nature is able to bring order out of chaos. The simplest living organism, for example, is a marvel of order and purpose. The ordering principle cannot be explained simply from the low-entropy content of its food. There must be something going on at a level which transcends the merely physical. The process by which this organism evolves into a more highly adapted one also defies a reductionistic explanation. Teilhard speaks of a radial and a tangential aspect of evolution. The tangential aspect involves the ordinary transformations of matter and energy and, of course, obeys the second law. The radial component, however, leads to greater interiorization, greater consciousness, gradually evolving new species. This component, he feels, does not need to obey the second law. It is this aspect which, in defiance of the second law, brings forth the new out of the ashes of the old. There seems to be a lesson here. What seems to us as chaos, in the suffering of our personal lives, in the dreadful state of world affairs, in the wounded planet we live on, is a necessary preliminary to the creation of something new. Let us embrace the chaos. To do less would be to deny reality. Let us also keep up our spirits with the hope that once again order will come out of the chaos. Dom Roberti |