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III.The Principle of Self-Organization Dissipative Structures A well-known
type of re-organization is the transformation of water from liquid
to vapor and ice. Although several scientists had
BbBenard Bénard cellsells more and the system turns to far from equilibrium, a critical point is reached when the whorls re-organize into a coherent whole, forming a lattice of six-sided cells. (A lattice is a three-dimensional arrangement in a geometric pattern.) If the heat is turned up even more the cells dissolve. A remarkable example of self-organizing systems in biology are slime molds. A slime mold is composed of thousands of amoebas that live individual lives but come together when hungry. When the individual vibrations produced by the hunger reach a critical point, they organize into a coherent entity that can move on the ground as a unit. When it reaches a desired location in the forest the mold sprouts a stalk and body that emits spores from which new amoebas are born, thus renewing the process.
Slime molds These are just a few examples of natural systems that exhibit both random and organized behavior. The elements exist independently until specific conditions drive them to organize into a coherent whole. There are many such systems in the natural world and Prigogine believes that this principle applies to a great variety of phenomena, both natural and man-made, from how individual neurons connect in the brain to form networks to how cities grow and human interactions take place. He called them dissipative structures. The term indicates the two natures of the structures: On the one hand the tendency to disperse in a disorderly way; on the other the ability to congregate and organize. With this discovery Prigogine gave a new meaning to the second law of thermodynamics. Thermodynamics is the science that studies the transformation of heat to and from other forms of energy. This phenomenon began to be studied in the early 19th century during the development of steam engines. It was observed that useful energy was lost to friction and heat and could not be retrieved. The continual loss of energy would run machines down and the second law of thermodynamics was derived from these observations. To find the rate of change in energy, the German physicist Rudolf Clausius introduced the concept of entropy. This is the measure of the amount of energy unavailable for useful work. Entropy is also a measure of the degree of disorder, i.e., the more entropy, the higher the disorder. Nevertheless, Prigogine showed that natural systems are capable of overcoming the tendency toward entropy by being open to the environment and interacting with it. The process takes place as follows. Natural systems possess feedback mechanisms. Feedback is a circular process in which a part or the whole of the output is fed back into the input. In a wider sense it refers to the transfer of information about the outcome of a process back to its source. Two types have been identified: linear and nonlinear. Linear feedback regulates systems by returning them to the point set initially. In this case the amount of output fed back into the input is the same and so the system is maintained stable. A well-known mechanism of this kind is the thermostat, a device that regulates the fluctuations in temperature of a dwelling, engine, and so on, by turning a heating or cooling unit on and off. An example of linear feedback in living organisms is homeostasis, the mechanism that maintains the organism's inner stability by spontaneously compensating for changes in the environment. For instance, sweating cools the body when it is hot and shivering heats it when it is cold. Feedback, however, amplifies the state of a system when the process entails increasingly larger amounts of output fed back into the input. This feedback is nonlinear. (A nonlinear rate of change is plotted on a graph with a line that curves upward. An example is interest paid both on the capital and on the interest. The amount always increases.) A classical case is that of a microphone placed too close to a loudspeaker. The output from the amplifier is picked up by the microphone, fed back into the amplifier and emitted by the speakers. The effect is a screeching sound. If the microphone is not moved the sound becomes increasingly louder because of the self-reinforcing effect of nonlinear feedback between amplifier and microphone. Nevertheless, Prigogine showed that in dissipative structures the amplifications produced by nonlinear feedback loops generate reorganization. This is especially true of living organisms because of the constant flow of energy and matter through the system. The molecules of life have been found to be a revealing case. Hypercycles
The German biochemist and Nobel laureate Manfred Eigen was
the
Catalysts are substances that initiate, accelerate or slow
down the rate of chemical reactions without themselves undergoing
change in the process. Enzymes, found in yeast and saliva,
are the most common and efficient catalysts. While studying processes
in biochemical systems The following is what happens. Like all molecules, the molecules of life - proteins, nucleic acids, carbohydrates, and sugars - are composed of atoms. The electrons in the atoms have spin - a type of rotation around their axis - and revolve around a nucleus, composed of protons and neutrons, in orbits of various shapes. (Spin or angular momentum can be either left or right and is the product of the speed of rotation and moment of inertia.) There is as much relative space between the nucleus and the electrons as there is between the sun and the planets. To some extent one may think of an atom as a miniature solar system. Unlike
planets, however, electrons change orbits farther from and closer
to the nucleus. They move farther when they absorb energy and closer
when they emit it.
(This model of the atom was formulated by the Danish physicist and
Nobel laureate Niels Bohr during the early development of atomic theory.
Today, scientists do not speak of orbits but of electron clouds and
energy levels.)
The energy is provided by the sun in the form of particles
of light called photons. The elemental unit of energy in electrons,
photons, and other subatomic particles is the quantum, and
that is why the study of atoms and their components is called quantum
physics. The laws of electricity, magnetism, and by Carbon 60
The revolutions
and spin of electrons make them vibrate. The vibrations generate waves
that are shaped in accordance with the harmonic principles
of frequency, length, and amplitude, the same that govern music.The
higher the frequencies are, the more complex the shapes will be.
(The electro-magnetic
spectrum, from radio waves at the low frequency end to gamma rays
at the high frequency end, of which the visible portion of colors
from red to violet is one small section, Vibrating atoms cause biomolecules to vibrate. A concentration of vibrating molecules, together with catalysts, temperature and pressure produce ever-larger vibrations. When the intensity goes beyond a critical point in the cycle the process may take a new course. If this new course involves the whole system biomolecules are forced to reorganize to a new state that may be more complex than the original and possess new qualities. In this case the amount of information that can be handled and the functions that can be performed will be greater. When they reach a certain level of complexity biomolecules close in the shape of a loop. reproduce themselves. Each time this occurs an enzyme is produced. A group of enzymes may reciprocally catalyze their own formation in such manner that a closed loop or catalytic cycle is generated. When this occurs catalytic cycles link with each other and form hypercycles. It is through this process of repetition and reorganization that biomolecules evolve at higher levels of complexity.
Repetition of a process and feedback, both negative and positive, provide for the maintenance, growth, development and evolution, both small and large, of natural systems. Recently it was discovered that they also generate the countless shapes found in Nature. |
investigated the phenomenon of reorganization in physical systems
dynamically at far from equilibrium, the Russian-born physical chemist
and Nobel laureate Ilya Prigogine was the first to carry out
in-depth studies and provide detailed description of how physical
systems convert disorder into order when subjected to high-energy
input. He was especially drawn to the phenomenon known as the Bénard
cells. When a pan with a thin layer of water is heated uniformly
from below, as long as the system is dynamically at equilibrium the
molecules move in a disorganized and random manner. When the heat
is turned up, however, whorls begin to form that become increasingly
agitated. As the heat is increased
even 
first
to apply the principle of self-organization to the issue of the development
of living systems. Eigen studies showed that the evolution of living
organisms could have been the result of a process of progressive organization
of molecules possessing special nonlinear feedback mechanisms called
catalytic cycles.
subjected
to inputs of energy, Eigen discovered that different catalytic cycles
linked to form feedback loops in which enzymes produced in one cycle
became the catalysts of the next. When going through phases of instability,
he found, these hypercycles, as he called them, can create
successively higher levels of organization characterized by increased
richness and diversity of components and structure. He also discovered
that they were very stable, able to reproduce themselves and correct
reproduction errors. 
extension
of chemistry and life, are the result of the exchanges of photons
between electrons. 
is determined by the same principles.) The
waves fill the entire atomic space - hence the notion of clouds -
and their shapes determine the properties, function, and behavior
of each atom. The fundamental equation that describes the probability
of the evolution of the shape of the waves - the so-called wave
function - was developed by the Austrian physicist and Nobel
laureate Erwin Schôdinger.
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