A collection of essays explores the aesthetic, graphic, literary, scientific, mathematical, and computer-related aspects of the spiral in nature and in the man-made world.

The first comprehensive book on the topic in half a century explores recent symmetry – and symmetry breaking – related discoveries, and discusses the questions and answers they raise in diverse disciplines: particle and high-energy physics, structural chemistry and the biochemistry of proteins, in genetic code study, in brain research, and also in architectural structures, and business decision making, to mention only a few examples.

From the tiny twisted biological molecules to the gargantuan curling arms of many galaxies, the physical world contains a startling repetition of spiral patterns. Today, researchers have a keen interest in identifying, measuring, and defining these patterns in scientific terms. Spirals play an important role in the growth processes of many biological forms and organisms. Also, through time, humans have imitated spiral motifs in their art forms, and invented new and unusual spirals which have no counterparts in the natural world. Therefore, one goal of this multiauthored book is to stress the conspicuous role that spirals play in science, and to show the reader how to create such spirals using a computer. Another goal is to show how simple mathematical formulas can reveal magnificent shapes and images. This interdisciplinary book revolves around a common theme, spiral symmetry, and is intended for scientists, humanists, and interested laypeople.

Explains and illustrates some fifteen aspects of symmetry-related subjects.

No detailed description available for "Symmetries of Nature".

It is gratifying to launch the third edition of our book. Its coming to life testi?es about the task it has ful?lled in the service of the com- nity of chemical research and learning. As we noted in the Prefaces to the ?rst and second editions, our book surveys chemistry from the point of view of symmetry. We present many examples from ch- istry as well as from other ?elds to emphasize the unifying nature of the symmetry concept. Our aim has been to provide aesthetic pl- sure in addition to learning experience. In our ?rst Preface we paid tribute to two books in particular from which we learned a great deal; they have in?uenced signi?cantly our approach to the subject matter of our book. They are Weyl’s classic, Symmetry, and Shubnikov and Koptsik’s Symmetry in Science and Art. The structure of our book has not changed. Following the Int- duction (Chapter 1), Chapter 2 presents the simplest symmetries using chemical and non-chemical examples. Molecular geometry is discussed in Chapter 3. The next four chapters present gro- theoretical methods (Chapter 4) and, based on them, discussions of molecular vibrations (Chapter 5), electronic structures (Chapter 6), and chemical reactions (Chapter 7). For the last two chapters we return to a qualitative treatment and introduce space-group sym- tries (Chapter 8), concluding with crystal structures (Chapter 9). For the third edition we have further revised and streamlined our text and renewed the illustrative material.

Symmetry is a fundamental principle of broad concern from the physical sciences to art and design. Much of its significance derives from the perceptual appeal of symmetry to the human brain, as testified by its universal inclusion in those icons of decor--oriental rugs. Although there have been many books on physical symmetry, none have addressed the issue of human symmetry perception. This comprehensive collection provides a wide range of approaches to the study of how we see symmetries, from evolutionary through empirical to extended theoretical treatments. The book is an invaluable resource for those concerned with the methods and analytic approaches to this challenging topic. It soon becomes evident that symmetry perception is not a simple example of neural pattern processing, since the essence of symmetry is to transcend the patterns of which it is composed. Consequently, this volume contains many novel methods relevant to the analysis of the long-range processing of mid-level vision rather than early neural filtering. It provides both a historical background and an intellectual stimulant to future developments in this lapidary field of study.

Looking beyond the boundaries of various disciplines, the author demonstrates that symmetry is a fascinating phenomenon which provides endless stimulation and challenges. He explains that it is possible to readapt art to the sciences, and vice versa, by means of an evolutionary concept of symmetry. Many pictorial examples are included to enable the reader to fully understand the issues discussed. Based on the artistic evidence that the author has collected, he proposes that the new ars evolutoria can function as an example for the sciences.The book is divided into three distinct parts, each one focusing on a special issue. In Part I, the phenomenon of symmetry, including its discovery and meaning is reviewed. The author looks closely at how Vitruvius, Polyclitus, Democritus, Plato, Aristotle, Plotinus, Augustine, Alberti, Leonardo da Vinci and Durer viewed symmetry. This is followed by an explanation on how the concept of symmetry developed. The author further discusses symmetry as it appears in art and science, as well as in the modern age. Later, he expounds the view of symmetry as an evolutionary concept which can lead to a new unity of science. In Part II, he covers the points of contact between the form-developing process in nature and art. He deals with biological questions, in particular evolution.The collection of new and precise data on perception and knowledge with regard to the postulated reality of symmetry leads to further development of the evolutionary theory of symmetry in Part III. The author traces the enormous treasure of observations made in nature and culture back to a few underlying structural principles. He demonstrates symmetry as a far-reaching, leading, structuring, causal element of evolution, as the idea lying behind nature and culture. Numerous controllable reproducible double-mirror experiments on a new stereoscopic vision verify a symmetrization theory of perception.

Symmetry and the causes of shifts in different types of symmetries in flowers follow specific patterns that are ruled by developmental and genetic factors. Using a unified system of phyllotaxic equations, we have modeled the molecular mechanisms and pressure forces that act in inflorescence and floral meristems, giving flowers their organ arrangement. In this book, we state general physical principles, whereby the symmetry of the perianth is derived from the symmetry of certain TCP gene expression. Thus, we define the interplay between the expression of CYC2-like genes and the phyllotactic mechanisms. This new evo-devo approach is applied to major groups of angiosperms with predominantly actinomorphic flowers (in which rare zygomorphy is positional) and groups with mainly bilaterally symmetrical flowers (in which zygomorphy is constitutional). It has thus allowed us to revisit the contributions of the great floral morphologists of the 20th and early 21st centuries.