Some Dynamic Ideas
We move now from the relatively familiar world of atoms and molecules into another fascinating area of physics known as thermodynamics. The reason we are following this path is that thermodynamics lies between the non-living realm of solids, liquids and gasses and the much more complex realm of living things.
Thermodynamics, as the name suggests, has to do with understanding what happens when we add heat (thermo-) energy to a dynamic system. A system is a group of parts which are viewed as interacting and, for the purposes of physical experiment, isolated from external influences except those variables which the experimenter is trying to control. In a dynamic system, we consider factors such as matter, motion and gravity, which Isaac Newton discovered follow certain principles which he called dynamics.
Instead of relatively cold or constant-temperature objects moving according to physical principles like a grandfather clock, the importance of heat energy and thermodynamics became increasingly significant in the 19th Century as attention was given to creating more efficient steam engines to drive the industrial revolution.
The Conservation of Energy
The "Laws of Motion" and other discoveries of Newton led to great scientific fervor in the 19th Century. Static electricity, which causes a rubbed amber rod to attract tiny pieces of paper, was discovered to move as a current which could be produced by a chemical battery. Electricity could also produce light and heat. Magnetism could be used to create electricity, and vice versa. In 1847, Joule determined that all these forms of energy, as the underlying force became known, were interchangeable. He wrote:
"Indeed the phenomena of nature, whether mechanical, chemical or vital, consist almost entirely in a continual conversion of attraction through space, living force (N.B., kinetic energy) and heat into one another. Thus it is that order is maintained in the universe [Author’s emphasis ] – nothing is deranged, nothing is ever lost, but the entire machinery, complicated as it is, works smoothly and harmoniously. . . and everything may appear complicated and involved in the apparent confusion and intricacy of an almost endless variety of causes, effects, conversions, and arrangements, yet is the most perfect regularity preserved – the whole being governed by the sovereign will of God."1
Thus we see that, even in the mid-19th Century, Joule (and other scientists) believed that order was an essential aspect of the universe, a universe in which energy is neither created nor destroyed, but simply converted in an orderly manner from one form into another, according to the will of God. Joule’s concepts were close in many ways to the key concepts of Ordergonics. This view of the universe was extended into a view of society and of humans as energy-transforming machines, and even the psychoanalytic theories of Sigmund Freud were deeply influenced by this mechanical concept of energy conversion. The principle of conservation of energy was so widely accepted that it became known as the First Law of Thermodynamics.
As Jeremy Rifkin explains this Law:
"The most important thing to remember, again, is that we cannot create energy. No person has ever succeeded in doing it and no person ever will. The only thing we can do is transform energy from one state to another. This is a heavy realization to come to when we stop to consider that everything is made out of energy. The shape, form, and movement of everything that exists is really only an embodiment of the various concentrations and transformations of energy. A human being, a skyscraper, an automobile, and a blade of grass all represent energy that has been transformed from one state to another. When the skyscraper is razed, and the blade of grass dies, the energy they embodied doesn't disappear. It is merely transformed into the environment."2
The Second Law Of Thermodynamics
The second law of thermodynamics states that, in a closed system, the amount of available energy tends to dissipate into less useful or less ordered forms. In the 19th Century scientists observed that energy available in pressurized hot steam to drive an engine is converted into work and heat, neither of which can be used to drive the engine any more. The amount of energy no longer available for being converted into work is called entropy, a term which has been much misused in modern times to mean the tendency of any order to erode over time.
Whenever energy is fully consumed to produce work in the world, it dissipates into a form that cannot be used to produce more work. Many people see in this second law of thermodynamics a paradigm of what is happening to the earth today. More and more, the energy available in oil and other fossil fuels is being burned to drive our automobiles, electric power plants and other machines that support our energy-consuming lifestyle. This energy then dissipates into the atmosphere where, along with the increase in air pollution, it contributes to the warming of the earth. Not only is the earth running out of fossil fuel, which represents energy from the sun trapped millions of years ago, but also the burning of this fuel is creating global warming which eventually could cause the melting of polar ice caps, the flooding of worldwide coastal areas and other major threats to civilization.
Entropy And The Arrow Of Time
Entropy is responsible for what Sir Arthur Eddington identified as the Arrow of Time. While Newtonian dynamics considered time reversible, the second law of thermodynamics says that, because energy tends irreversibly to dissipate, time points in only one direction, into the future, and we can never go back. Perhaps you have seen movies run in reverse where cars back up, people fly upside down from pools onto diving boards, smashed teacups reconstruct themselves on table tops, spilled milk gathers back into the bottle, and many other sometimes hilarious events occur. We laugh because it is so impossible. The movie of life never runs in reverse. The Arrow of Time points in only one direction.
As we consider the relationship between order and energy, then, we come to a very important realization: that energy is needed to restore or maintain order in dynamic systems. Elevators come down by gravity. To get them back up again, we must expend energy. While on one hand the universe is running down, burning out, because of entropy, on the other hand some expenditure of energy is creating ever higher forms of order. The worldwide communications system which includes satellite transmissions and telephones everywhere, which lets you contact someone halfway round the world by pressing a few buttons on your telephone, is just one of thousands of examples of a high level of order which was created and is maintained by an enormous amount of energy.
Entropy And Probability
The irreversibility of thermodynamics compared with the reversibility of classical dynamics intrigued many physicists. Ludwig Boltzmann saw that the tendency of order in a system to disperse to a state of uniformity or symmetry throughout the system could be expressed in terms of probability. It is much more probable, he reasoned, that the energy in a system will be spread uniformly than that the energy will be concentrated in one spot. This application of the new mathematics of probability to thermodynamics was to have many important consequences.
Prigogine and Stengers observe, "Probability can adequately explain a
system's forgetting of all initial dissymmetry, of all special distributions.
... This forgetting is possible because, whatever the evolution peculiar to the
system, it will ultimately lead to... disorder and maximum symmetry. Once this
state has been reached, the system will move only short distances from the
state, and for short periods of time. In other words, the system will merely
fluctuate around the attractor [rest or disorder] state."3
For example, let us suppose that we had a closed container divided in half.
In the left half are molecules of oxygen, in the right half molecules of
nitrogen. If we remove the divider between them, the two halves quickly become
equally filled with both oxygen and nitrogen. While the divided state
represented a higher level of order, the combined state represents disorder,
symmetry and increased entropy. Now, we can imagine that it might be possible,
with all those molecules zooming about, for all the oxygen to return to its end
of the container and all the nitrogen to its end "on their own." But as
Boltzmann pointed out, that would be highly improbable, so improbable as to be
virtually impossible. What is most probable is that the molecules and the two
gasses will remain evenly and equally dispersed. This condition is known as
equilibrium, whereas a condition with a high degree of order or organization is
called "far from equilibrium." As we will see when we discuss the relationship
between order and energy in living organisms, the conditions within living cells
is far from equilibrium and requires a constant processing of energy.
For example, let us suppose that we had a closed container divided in half. In the left half are molecules of oxygen, in the right half molecules of nitrogen. If we remove the divider between them, the two halves quickly become equally filled with both oxygen and nitrogen. While the divided state represented a higher level of order, the combined state represents disorder, symmetry and increased entropy. Now, we can imagine that it might be possible, with all those molecules zooming about, for all the oxygen to return to its end of the container and all the nitrogen to its end "on their own." But as Boltzmann pointed out, that would be highly improbable, so improbable as to be virtually impossible. What is most probable is that the molecules and the two gasses will remain evenly and equally dispersed. This condition is known as equilibrium, whereas a condition with a high degree of order or organization is called "far from equilibrium." As we will see when we discuss the relationship between order and energy in living organisms, the conditions within living cells is far from equilibrium and requires a constant processing of energy.
Equilibrium Structures Are Timeless
"Equilibrium structures can be seen as the results of statistical compensation for the activity of microscopic elements (molecules, atoms)," note Prigogine and Stengers.4 In our example of the two gasses in a container, the uniform distribution of the gas molecules at the microscopic level leads to the observation that the container is at equilibrium, even though individual molecules are still moving rapidly about. Because equilibrium structures are inert, they do not change with time. Once these equilibrium structures have been formed, "they may be isolated and maintained indefinitely without further interaction with their environment."5 Think of our airtight container of the two gasses – it could be left on a shelf for decades if not centuries and, when examined, would be found to still contain the two gasses in uniform distribution.
Why Is The Universe Not Uniform?
While physicists make much of the second law of thermodynamics, it is very interesting to note that this should lead to a universe of complete uniformity. That is, the "natural" tendency of matter and energy is to completely disperse into a uniform state. If that were the case, the universe would consist of nothing but completely dispersed energy! Instead, there is and always has been a high degree of order in the universe, shaping the energy/matter into clouds, then solid objects. Order has been a component of the universe since the very beginning.
In this chapter and the preceding one, we have talked about order and energy at the atomic level through the molecular level, introducing the concepts of thermodynamics and entropy. Since this information may be somewhat new to many readers, it may be helpful at this point to summarize:
1. All physical entities in the universe, from atoms to humans to galaxies, are composed of subatomic particles which consist of bundles of ordered energy.
2. All physical entities consist of energy, and energy can neither be created nor destroyed, only converted from one form to another.
3. Within closed systems, the component parts have a strong tendency to move to a state of uniform distribution, increased disorder, dispersed energy or entropy.
4. The principle of entropy means that the Arrow of Time points in only one direction, toward a future of increased entropy.
5. Yet the very existence of matter, in addition to its forms in particles, atoms, molecules and more complex structures, defies the entropic principle and points to the tremendous power of order at work in the universe.
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