Selforganization by Nonlinear Irreversible Processes


Book Description

These Proceedings contain invited lectures presented at the third Interna tional Conference on "Irreversible Processes and Dissipative Structures" in Kiihlungsborn (German Democratic Republic) in March, 1985. These con ferences, the first of which was held in Rostock in 1977 and the second in Berlin in 1982, are devoted to the study of irreversible processes far from thermal equilibrium and to the phenomena of selforganization. The meet ing in Kiihlungsborn brought together some 160 mathematicians, physicists, chemists and biologists from 10 countries, who are all interested in the inter disciplinary field of synergetics. The main topics of the conference were basic concepts of selforganization and evolution, such as entropy, instabilities, nucleation, dissipative struc tures, chaos and turbulence. The contributions cover methods from ther modynamics, the theory of dynamic systems, stochastic and statistic theory, the method of Green's functions, the fluctuation-dissipation theorem, etc. Several problems are studied in more detail, e.g., the kinetics of nucleation especially in finite systems, the dynamics of interfaces, reaction-diffusion sys tems, chemical and biochemical pattern formation and information process ing. Further, several contributions are devoted to the development of the concepts of chaos and turbulence. The editors hope that the contributions collected in this volume will pro vide some new information about the field of selforganization, which is in full development now.




Self-Organization in Nonequilibrium Systems


Book Description

Membranes, Dissipative Structures, and Evolution Edited by G. Nicolis & R. Lefever Focuses on the problem of the emergence/maintenance of biological order at successively higher levels of complexity. Covers the spatiotemporal organization of simple biochemical networks; the formation of pluricellular or macromolecular assemblies; the evolution of these structures; and the functions of specific biological structures. Volume 29 in Advances in Chemical Physics Series, I. Prigogine & Stuart A. Rice, Editors. 1975 Theory and Applications of Molecular Paramagnetism Edited by E. A. Boudreaux & L. N. Mulay Comprehensively treats the basic theory of paramagnetic phenomena from both the classical and mechanical vantages. It examines the magnetic behavior of Lanthanide and Actinide elements as well as traditional transition metals. For each class of compounds, appropriate details of descriptive and mathematical theory are given before their applications. 1976 Theory and Aapplications of Molecular Diamagnetism Edited by L. N. Mulay & E. A. Boudreaux An invaluable reference for solving chemical problems in magnetics, magnetochemistry, and related areas where magnetic data are important, such as solid-state physics and optical spectroscopy. 1976




Propagation in Systems Far from Equilibrium


Book Description

Macroscopic physics provides us with a great variety of pattern-forming systems displaying propagation phenomena, from reactive fronts in combustion, to wavy structures in convection and to shear flow instabilities in hydrodynamics. These proceedings record progress in this rapidly expanding field. The contributions have the following major themes: - The problems of velocity selection and front morphology of propagating interfaces in multiphase media, with emphasis on recent theoretical and experimental results on dendritic crystal growth, Saffman-Taylor fingering, directional solidification and chemical waves. - The "unfolding" of large-scale, low-frequency behavior in weakly confined homogeneous systems driven far from equilibrium, and more specifically, the envelope approach to the mathematical description of textures in different cases: steady cells, propagating waves, structural defects, and phase instabilities. - The implications of the presence of global downstream transport in open flows for the nature, convective or absolute, of shear flow instabilities, with applications to real boundary layer flows or shear layers, as reported in contributions covering experimental situations of fundamental and/or engineering interest.




Modelling the Dynamics of Biological Systems


Book Description

The development of a proper description of the living world today stands as one of the most significant challenges to physics. A variety of new experimental techniques in molecular biology, microbiol ogy, physiology and other fields of biological research constantly expand our knowledge and enable us to make increasingly more detailed functional and structural descriptions. Over the past decades, the amount and complexity of available information have multiplied dramatically, while at the same time our basic understanding of the nature of regulation, behavior, morphogenesis and evolution in the living world has made only modest progress. A key obstacle is clearly the proper handling of the available data. This requires a stronger emphasis on mathematical modeling through which the consistency of the adopted explanations can be checked, and general princi ples may be extracted. As an even more serious problem, however, it appears that the proper physical concepts for the development of a theoretically oriented biology have not hitherto been available. Classical mechanics and equilibrium thermody namics, for instance, are inappropriate and useless in some of the most essen tial biological contexts. Fortunately, there is now convincing evidence that the concepts and methods of the newly developed fields of nonlinear dynam ics and complex systems theory, combined with irreversible thermodynamics and far-from-equilibrium statistical mechanics will enable us to move ahead with many of these problems.




Synergetic Computers and Cognition


Book Description

This book presents a novel approach to neural nets and thus offers a genuine alternative to the hitherto known neuro-computers. The new edition includes a section on transformation properties of the equations of the synergetic computer and on the invariance properties of the order parameter equations. Further additions are a new section on stereopsis and recent developments in the use of pulse-coupled neural nets for pattern recognition.




Foundations of Synergetics I


Book Description

This book gives an introduction to the mathematical theory of cooperative behavior in active systems of various origins, both natural and artificial. It is based on a lecture course in synergetics which I held for almost ten years at the University of Moscow. The first volume deals mainly with the problems of pattern fonnation and the properties of self-organized regular patterns in distributed active systems. It also contains a discussion of distributed analog information processing which is based on the cooperative dynamics of active systems. The second volume is devoted to the stochastic aspects of self-organization and the properties of self-established chaos. I have tried to avoid delving into particular applications. The primary intention is to present general mathematical models that describe the principal kinds of coopera tive behavior in distributed active systems. Simple examples, ranging from chemical physics to economics, serve only as illustrations of the typical context in which a particular model can apply. The manner of exposition is more in the tradition of theoretical physics than of in mathematics: Elaborate fonnal proofs and rigorous estimates are often replaced the text by arguments based on an intuitive understanding of the relevant models. Because of the interdisciplinary nature of this book, its readers might well come from very diverse fields of endeavor. It was therefore desirable to minimize the re quired preliminary knowledge. Generally, a standard university course in differential calculus and linear algebra is sufficient.




Synergetics of Cognition


Book Description

This book presents the invited lectures given at the International Symposium on Synergetics of Cognition held at SchloB Elmau, Bavaria (Fed. Rep. of Germany), June 4-8, 1989. The understanding of the processes underlying cognition is certainly one of the most challenging and difficult problems confronting the human mind. It is an enterprise that requires the cooperation of scientists from fields ranging from the neurosciences and psychology through biology to the computer sciences, physics and mathematics. The papers included in this volume reflect this joint effort. As will be evident, there is a remarkable convergence of ideas stemming from various fields, for instance, the earlier ideas on Gestalt theory celebrate a come back and remarkable analogies are being established with modem concepts of self-organization as dealt with in the interdisciplinary field of synergetics. The individual topics range from the "microscopic level", where new exciting results on specific oscillations of neural activity are reported, to computer simulations of perception, and finally psychological experiments at the "macroscopic level". We hope that this book will convey to its readers the same enthusiasm that was felt by the participants of the symposium. We wish to thank Mrs. U. Funke for the excellent organisation of the sym posium, and the Volkswagen-Stiftung, Hannover, for its financial support. We are furthermore grateful to Christoph Stadler and Zora Franko for their help in com piling the name and subject indexes. Finally we wish to thank Springer-Verlag, in particular Dr. Angela Lahee, for the excellent cooperation.




Cooperative Dynamics in Complex Physical Systems


Book Description

Many novel cooperative phenomena found in a variety of systems studied by scientists can be treated using the uniting principles of synergetics. Examples are frustrated and random systems, polymers, spin glasses, neural networks, chemical and biological systems, and fluids. In this book attention is focused on two main problems. First, how local, topological constraints (frustrations) can cause macroscopic cooperative behavior: related ideas initially developed for spin glasses are shown to play key roles also for optimization and the modeling of neural networks. Second, the dynamical constraints that arise from the nonlinear dynamics of the systems: the discussion covers turbulence in fluids, pattern formation, and conventional 1/f noise. The volume will be of interest to anyone wishing to understand the current development of work on complex systems, which is presently one of the most challenging subjects in statistical and condensed matter physics.




The Physics of Structure Formation


Book Description

The formation and evolution of complex dynamical structures is one of the most exciting areas of nonlinear physics. Such pattern formation problems are common in practically all systems involving a large number of interacting components. Here, the basic problem is to understand how competing physical forces can shape stable geometries and to explain why nature prefers just these. Motivation for the intensive study of pattern formation phenomena during the past few years derives from an increasing appreciation of the remarkable diversity of behaviour encountered in nonlinear systems and of universal features shared by entire classes of nonlinear processes. As physics copes with ever more ambi tious problems in pattern formation, summarizing our present state of knowledge becomes a pressing issue. This volume presents an overview of selected topics in this field of current interest. It deals with theoretical models of pattern formation and with simulations that bridge the gap between theory and experiment. The book is a product of the International Symposium on the Physics of Structure Formation, held from October 27 through November 2, 1986, at the Institute for Information Sciences of the University of Tiibingen. The symposium brought together a group of distinguished scientists from various disciplines to exchange ideas about recent advances in pattern formation in the physical sciences, and also to introduce young scientists to the fi




Inside Versus Outside


Book Description

In our daily lives we conceive of our surroundings as an objectively given reality. The world is perceived through our senses, and ~hese provide us, so we believe, with a faithful image of the world. But occ~ipnally we are forced to realize that our senses deceive us, e. g. , by illusions. For a while it was believed that the sensation of color is directly r~lated to the frequency of light waves, until E. Land (the inventor of the polaroid camera) showed in detailed experiments that our perception of, say, a colored spot depends on the colors of its surrounding. On the other hand, we may experience hallucinations or dreams as real. Quite evidently, the relationship between the "world" and our "brain" is intricate. Another strange problem is the way in which we perceive time or the "Now". Psychophysical experiments tell us that the psychological "Now" is an extended period of time in the sense of physics. The situation was made still more puzzling when, in the nineteen-twenties, Heisenberg and others realized that, by observing processes in the microscopic world of electrons and other elementary particles, we strongly interfere with that world. The outcome of experiments - at least in general - can only be predicted statistically. What is the nature ofthis strange relationship between "object" and "observer"? This is another crucial problem of the inside-outside or endo-exo dichotomy.