General theoretical conception of “entropy” and “information” in modern science

 

Kazhikenova S., Sagyt E.

 

At present science needs a new paradigm because all the aspects of the information structure depend on mechanisms of real vital activity. In the present day world information presents one of the most important resources, one of the motive forces of the humanity development. In the middle of the XX century there took place two events that, in our opinion, in a significant degree define the further ways of science development, the world scientific understanding, any objects’ theoretical and practical perfection. Here we speak of developing the theory of information, establishing the characteristics of information measures and of beginning the analyzing of entropic-information criteria mechanisms, for which studying synergy attracts all the latest achievements in unbalanced thermodynamics, theory of information and general theory of systems. The aspiration for the determinate description of real processes leads inevitably to the subject or object idealism and by this introduces into the process and the result of cognition stochasticity connected with diversity of points of view, interpretations and versions of different authors.

The occurrence of theory of information is closely related to the name of C. Shannon who suggested a solution of the main problem of finding the information transferring speed that can be achieved at the optimal method of coding and decoding so that the probability of error was as small as possible. Theory of coding is characterized by that alongside with statistical methods it uses for building concrete codes deep algebraic and combinatory ideas.

The work “entropy” was fir first time used in 1865 by German physicist Rudolf Clausius for naming a value characterizing the processes of thermal energy transition into mechanical one. In his main scientific work, a three-volume monograph “Mechanical theory of heat” R. Clausius explains in details the expediency of introducing this quite specific, new concept. Speaking of that “heat cannot itself come from one cooler body to a warmer one”, R. Clausius proved that there does not exist a method of heat transition from a cooler body to a warmer one without some changes in the nature that could compensate such a transition. His idea to name the new function of state the German scientist explained in such a way: “trope” means in Greek “transformation”; two letters “en” were taken from the work “energy”, as both values are close to each other in their physical relevance. Using the conception of entropy and Clausius’s inequality, there can be formulated the second origin of thermodynamics as a law of increasing the closed system entropy in irreversible processes: any irreversible process in a closed system takes place in such a way that the system entropy increases.

However, the formula of entropy suggested by the scientist did not revealed the inner mechanisms of the processes leading to the entropy increase. This problem was solved by Ludwig Boltzmann (1872), who suggested a formula connecting entropy with the logarithm of the system state probability. “General thermodynamics, − L. Boltzmann wrote, − adheres to unconditional irreversibility of all natural processes. It takes the function (entropy) whose value in any event can change only one-sidedly, for example, it can increase. Thus, any later state of the Universe differs from any earlier state by a larger entropy value. The difference between entropy and its maximum value, that is a motive force of all the natural processes, becomes smaller and smaller. In spite of the total energy invariability, its ability to transformations becomes smaller, the natural events become more lifeless, and any return to the former amount of entropy is excluded”. The system thermodynamic state entropy is determined through thermodynamic probability as: S = k·lnW, where k is Boltzmann’s constant. This entropy expression through thermodynamic probability is called “Boltzmann’s principle”. Thus, Boltzmann’s constant k occurrence can be considered as a consequence of connection between thermodynamic and statistic definitions of entropy.

Not less interesting discoveries were made by scientists I. Prigozhin and I. Stengers in the book “Order out of chaos” where they give convincing arguments of that irreversible processes are a source of order, generating high levels of organization. In the authors’ opinion, entropy is not simply a system unceasing sliding to a state without any organization, but under certain conditions it is a progenitress of order and finally, of life. The authors of the book underline a possibility of the spontaneous occurrence of order and organization out of disorder and chaos as a result of the process of self-organization. 

Besides, on the basis of analyzing complicated physical, chemical phenomena scientists prove the theorem of entropy minimum production (of reducing the temps of the disorder measure increase) in stationary unbalanced phenomena , proving the possibility of order occurrence out of chaos if there external impacts that always take place in the real world. The formed order in the form of structures of spatial-time, functional characteristics is described not only by external factors but in a greater extent by the characteristics of the complicated object itself. That’s why this law is called self-organization. Later on a lot of studies of different authors showed the universality of this phenomenon. Evolution of open systems exchanging with the environment the matter, energy and information is always followed by the process of self-organization. 

In works by I. Prigozhin as the main postulate there is taken the formulated at the microscopic level the second law of thermodynamics, i.e. the law of entropy increasing and time asymmetry. Besides, there is introduced a new concept, the internal time characterizing the processes in unstable dynamic systems. On a lot of examples from physics, chemistry and biology there is demonstrated a constructive role of irreversible processes. For outstanding services in the field of thermodynamics of irreversible processes I. Prigozhin was conferred a Noble Prize.

The interaction between information and self-organization based on the principle of information entropy maximum in relation to a wide circle of unbalanced processes is spoken of by Herman Haken who is by right considered the flounder of synergy. The author considers the synergetic approach to the problem of images recognition using methods of studying various systems: from biological to quantum. He makes a conclusion that “information is the decisive element of existing the life itself’ and is connected with the transmission capacity of a communication channel or with the commands acquiring the role of the environment from which there is obtained the concrete information.

Entropy and information, being the expression of two opposite tendencies in the processes of development, are reflected in the formula H + J = 1 (const). If a system evolves in the direction of order, its entropy decreases, however, it requires purposeful efforts and managing. One of the founders of cybernetics, American scientist N. Wiener, writes: “While entropy is a measure of disorganization, information transited by a certain flow of messages determines the measure of organization… We are drifting along the stream fighting against a great flow of disorganization which, in accordance with the II law of thermodynamics, is striving to bring everything to a thermal death – the global balance and similarity, that is to entropy”.

There can be cited a lot of works devoted to this subject and presenting scientific interest not only for a separate branch but for science on the whole. For example, American specialist in the field of physical-mathematical sciences, one of the pioneers of theory of chaos Ì. Feigenbaum, found universal numbers describing a structure of dynamic systems chaos and proved that any disorder has its internal order. Feigenbaum’s theory permits to conclude that between chaos and order there is a deep internal connection. An unperiodical, random process occurs as a limit of more complicated structures, chaos appears as a super-complicated organization. This conclusion is general, it can be related to models of ecology, hydrodynamics, chemistry, etc., i.e. to any systems where there is a sequence of the period doubling bifurcation.

An outstanding physicist-theoretician who made a great contribution into developing modern statistical physics and physics of open systems Yu.L. Klimontovich proved that for the processes of self-organization there acts another law – the law of entropy reducing. In other words, the analogue of Boltzmann’s Í-theorem for open systems is Klimontovich’s S-theorem whose essence is in the following: If in the capacity of the origin of randomness is taken “the balanced state” satisfying zero values of the governing parameters, then while moving away from the balanced state, due to the governing parameter changing, the entropy values relating to the given value of average energy, reduce. Thus, Klimontovich law of entropy decreasing gives a key to solving a fundamental collision of continuity and discreteness which has not yet found its solution.

A pioneer in the field of information theory is to be unconditionally considered R. Hartley. An indubitable service of this scientist is that for the first time he introduced the concept of “information” (entropy) as a random variable and defined the measure of information. Introducing a quantitative measure of information was the most important step on the way of perceiving the nature and anti-entropic processes, as originally this measure was aimed for solving only applied problems of communication engineering. The scientist suggested to estimate the amount of information by a logarithm of the number of possible events. However, Hartley considered non-essential the possibility of non-equally probable outcomes, understanding that outcome probabilities affect the information amount that is contained in a message. He considered that “difference between these outcomes cannot be expressed in numbers, and they are determined by psychological, metrological or some other factors not subject to the authority of mathematics”.

The following studies in the field of physics and biology permitted to reveal universal methods using which it is possible to establish an interconnection between the information amount and physical entropy and, in the end, to define the essence of a new scientific interpretation of the concept “information” as a measure of structural order of variable in their nature systems. American scientists C. Shannon proved that Hartley’s point of view is erroneous. Any factors – psychological, meteorological, and other – can be taken into account using theory of probability. Shannon began developing ideas that became the basis of his well-known theory of information. Shannon’s aim was to optimize the information transition over telephone and telegraph lines. To solve this problem he had to formulate what information was and how its amount could be measured. In his works he defined the information amount through entropy, a value known in thermodynamics and statistic physics as a measure of the system disorder. The unit of information was taken what was later on called “a bit”, i.e. a selection of one variant out of two equally probable. On the firm foundation of his definition of the information amount the scientists proved a surprising theorem of noisy communication channels bandwidth.