Book Reviews


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Genetic Algorithms & Engineering Optimization

Mitsuo Gen / Runwei Cheng (Both of Ashikaga Institute of Technology, Japan)

0-471-31531-1 Hardcover: US$99.00
Published: Dec 1999
Copyright: 2000

(Reviewer: Hae Chang Gea, Rutgers University)

This well-written book provides in-depth discussions of many engineering applications using GA and a comprehensive reference.  Because of the broad range of subjects covered in the book, it is more a reference book than a textbook.   This book is divided into nine chapters.   Chapter 1 covers fundamental concepts of GA such as encoding, genetic operators, adaptation and optimization.  It is a very compact introduction.  Therefore, for readers who are new to GA, further reading is recommended.

The focus of this book is on its in-depth discussion of engineering applications.  Starting from Chapter 2, a variety of engineering optimization problems are presented.   Chapter 2 discusses combinatorial optimization problems including set-covering problem, bin-packing problem, knapsack problem and minimum spanning tree problem.  For each kind of problems, detailed description of formulation, application of GA and their numerical experiences are provided. 

Chapter 3 devotes to multi-objective optimization problems.  Multi-objective optimization arises in many engineering design applications.  It is pleasant to read this chapter because it covers basic concepts and many different approaches to solving multi-objective optimization including Pareto ranking and tournament methods, weighted-sum, distance method, comprise approach and goal programming.  Furthermore, it provides GA implementation on each of them. 

Chapter 4 discusses fuzzy optimization problems on account of uncertainty and imprecision problem in engineering applications.  Similar to Chapter 3, many methods and their GA implementation are presented such as fuzzy linear programming, fuzzy nonlinear programming, and fuzzy multi-objective programming.  Chapters 2 to 4 present not only GA practice in engineering optimization but also many important issues in engineering design applications.  Equipped with these concepts, the next five chapters are moving to specific topics of the adaptation and application of GA.

Chapter 5 presents reliability design problems.  It covers network reliability design, tree-based network reliability and LAN design, and multi-objective reliability design.  Unfortunately, discussion is very limited to network design problems.  Concepts for probabilistic design optimization such as Limit State, reliability index and safety index are not included.

Chapter 6 covers scheduling problems.   Unlike chapter 5, it gives a comprehensive review and discussion in this subject.  This chapter begins with basic approaches to scheduling problems and then moves to specific job scheduling problems including grouped job scheduling, resource-constrained project scheduling, parallel machine scheduling and multi-processor scheduling.  GA implementations and numerical examples are also presented.

The last three chapters discuss advanced transportation problems, network design and routing, and manufacturing cell design.   They are extensions of chapters 5 and 6 with some advanced applications and discussions.  Therefore, they may not be interesting to general readers.  However, researchers in these areas may find many useful discussions and references. 

The bibliography, with 737 entries, is very useful.  The authors obviously have spent enormous time and energy to prepare this book.  However, in some cases, one could have wished for more recent journal publications and less Ph.D. dissertations.  In brief, this book is a very fine reference book for GA in engineering application.   This reviewer would recommend this book for graduate students and researchers in this area as an excellent resource for the topics covered.

-o-


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                "The Man Who Loved Only Numbers" by Paul Hoffman

                                                  Hyperion, New York, 1998.
                                         (Reviewed by Haym Benaroya, Rutgers)

When I first started to read this book, I wasn't sure what could be said about a man who was only interested in numbers. But quickly I began to learn much about not only Paul Erdös (pronounced "air-dish"), but about a large part of the mathematical world that revolved about him, and about which he orbited. We learn some interesting facts. For example, Erdös was a prolific researcher who published 485 papers with co-authors. His total papers published numbers 1475. This is an astounding number, especially considering that many are considered monumental. This quantity was only surpassed by the great Leonhard Euler.

Beyond the statistics of the man, we find out that he is a kind person. He is generous with ideas, passing them on to his colleagues without a worry regarding attribution. We meet many of Erdös' colleagues, upon whose friendship and generosity he depended for room and board. This is because Erdös did not maintain a home, but rather traveled from one location to another, continuing his mathematics wherever and whenever he went. Ronald Graham, a mathematician at AT&T Bell Labs, who Erdös visited regularly, even added a room and bathroom to his house to make the visit more comfortable for everyone.

Erdös believed that there is no more important activity than doing mathematics. He was a "mathematical monk. He renounced physical pleasure and material possessions for an ascetic, contemplative life, a life devoted to a single narrow mission: uncovering mathematical truth." Of course, he had a significant cadre of friends and colleagues who did everything else for him, thus permitting him to live such a cloistered life. He put out contracts on problems he was unable to solve, ranging from $10-$3,000, depending on the difficulty of the problem.

Erdös lived to the age of eighty-three, passing into the company of the SF (Supreme Fascist) on 20 September 1996. SF was Erdös' shorthand for God. He has other shorthand terms, for example, epsilon, the mathematical symbol used to signify small, was the term for children. Erdös was born in Budapest on March 26, 1913, the son of two high school mathematics teachers. He lived through the trials and tribulations of Europe during the first half of this century, moving about many times in response to the political chasms that opened and closed.

Erdös circumvented anti-Jewish laws regarding admissions to universities by winning a national competition to enter in 1930 the University Pázmány Péter in Budapest at the age of 17 and graduating four years later with a Ph.D.

This book is more than about Erdös, although his is the binding thread throughout. By virtue of his travels and his abilities, his life was intertwined with the scientific and intellectual life of the twentieth century. We read about Germaine, Hardy, Russell, Ramanujan, Gödel, Einstein, Fermat, Bellman and Weils, among many others.

There is also the news story from the 15 August 1945 Daily News with the headline 3 Aliens Nabbed at Short-Wave Station. Well, you guessed it, Erdös was one of the three, all of whom were mathematicians, who happened to ignore a no trespassing sign and decided to walk around on a Long Island beach. A policeman reported that they were speaking some foreign language. That language turned out to be mathematics.

Of course, there are numbers all over the place that even non-mathematicians can appreciate. Here is an example:

2,682,4404 + 15,365,6394 + 18,796,7604 = 20,615,6734

To find out what the meaning of this equation is, you will have to look in the book on page 217. The math is interesting and followable.

I tend to enjoy books about mathematicians and scientists. Even so, I must say that this is one of the best written such books. I found myself looking forward to every spare minute I could spend with Paul Hoffman's book. I enjoyed the photographs. I recommend it wholeheartedly. It is more than just a story about a mathematician. It is a story that touches all of us in many ways.

                                                                        -o-

                         Mechanical Engineers’ Handbook, Second Edition
                                                           Myer Kutz, Editor
                                                  Published by Wiley-Interscience
                                                        John Wiley & Sons, Inc.
                                          Professional, Reference and Trade Group
                                                             Cloth; $250.00
                                                       ISBN: 0-471-13007-9

                                         (Reviewed by Haym Benaroya, Rutgers)


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The second edition of the Mechanical Engineers’ Handbook edited by Myer Kutz, offers contributions from more than 80 leading experts in industry, government and academia. Myer Kutz, MSME, is founder and President of Myer Kutz Associates, Inc., publishing and information service consultants. This single, easy-to-use volume covers a broad spectrum of critical engineering topics, updating both engineers and engineering managers with developments in materials, methods, and equipment - from concurrent engineering and computer aided technology, to new composite materials and design and packaging techniques. In addition to material that remains unchanged, a third of the book consists of entirely new chapters, and some of the revisions, made by new authors, are so different from their predecessors that they could count as new chapters.

This edition opens with a thorough revision of the structure of solid materials, and includes important updates on nickel, aluminum, plastics and elastomers, and composites. Many of the chapters covering mechanical design fundamentals have been updated, and new requirements in manufacturing engineering called for essential revisions as well. New chapters focus on the roles of virtual reality, ergonomic design, electronic packaging, and pollution control technology, and the teamwork-based methods of product development that have evolved have also earned a prominent place in the second edition. The final section of the Handbook focuses on topics that address career growth, including developments in project management, detailed cost estimating, certifications and awards, and legal issues for engineers.

I immediately went to a chapter I have some knowledge about, Chapter 23 on Vibration and Shock, to investigate the thoroughness of the discussion. Although a different individual writes each chapter, this may be considered a measure of the quality of the remaining chapters. I read useful discussions of basic and more advanced topics. The figures are of good quality. However, the photos of equipment seemed to be from a previous generation. This appears to be borne out by the list of references that date from 1961-1981 (books) and a list of references from the Shock and Vibration Information Center that only reach 1979. With the major advances in materials and electronics, one would have hoped for a more up to date exposition.

The Mechanical Engineers’ Handbook has the following features:

  • A section on manufacturing engineering with four new and revised chapters
  • 7 new chapters on management, career, and legal issues
  • More than 1,300 charts, tables, photographs, and illustrations
  • Extensive cross-referencing and indexing for ease of use and searchability
  • Detailed, up-to-date reference sections at the end of each chapter
  • Directions to on-line databases and other information sources

The two editions of the Mechanical Engineers’ Handbook are separated by a dozen years. This is a massive book, weighing in at 2352 pages. The production is first-rate, with all chapters prepared in a visually professional style, including the figures. The cost, while breathtaking, is still minor for an office or a library that depends on such a reference. Even with the above specific comments about one chapter, this is still a worthwhile resource. (Reviewed by Haym Benaroya).

                                                    -o-

Weak Convergence of Probability Measures

by Patrick Billingsley

John Wiley & Sons, Second Edition, 1999 ISBN 0-471-19745

(Reviewed by Daniel Ocone, Professor of Mathematics, Rutgers University)

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Here is a problem that is at once a simple extension of the central limit question and a prototype of approximation issues in analysis of stochastic models. Take a random walk with independent steps, each having a zero mean and a variance s2. For a positive integer n, simultaneously rescale time so n steps are taken in each time unit and rescale step size by the central limit factor 1/n. Define the value of the process between step times by linear interpolation, so that sample paths are continuous, and denote the resulting process by Xn = {Xn(t);t ł 0}. At any fixed time t, Xn(t) is a normalized sum of independent random variables plus a negligible error, and hence, by the central limit theorem, Xn(t) converges in distribution as n® Ą to a normal random variable, regardless of the distribution of the original, unscaled steps. Likewise, the multi-dimensional central limit theorem identifies a normal limit of the sequence of random vectors {(Xn(t1),... ,Xn(tM))}, for any finite set of times. Is it possible to go further and find a limit in distribution of the sequence of processes {Xn}? This would be a process X that captures the limiting statistical behavior not just of Xn at fixed times, but of the paths of Xn; for example, the distributional limit of {sup[0,1]|Xn(t)|} would be given by {sup[0,1]|X(t)|}. How does one properly define distributional limits of processes, and what are general techniques for identifying them? The answer in the case of {Xn} -the limit is Brownian motion-can be interpreted as a functional central limit theorem. Think of each process Xn, not as a collection of random variables, but as a random element whose value is the continuous sample path t® Xn(t). From this point of view, a limit theorem for {Xn} is a generalization to random functions of the central limit theorem for finite-dimensional random vectors.

The central limit question for {Xn} is the motivating problem of Billingsley's text. The book presents the general theory of convergence in distribution for stochastic processes and uses it for an in-depth study of scaled random walks. This may not be apparent from the abstruse-sounding title,Weak Convergence of Probability Measures, but it is weak convergence theory for probability measures on a metric space that underpins the subject. The generality of the metric space setting covers both random variables and stochastic processes at once. A random variable takes values in the metric space consisting of the real line with the distance metric; for a stochastic process, we find a metric space of paths including all sample paths and interpret the process as a random element taking values in this space. For instance, the process {Xn(t); t Î [0,1]} of our example takes values in the space of continuous functions on [0,1], for which it is natural to use the supremum norm metric. The theory of weak convergence then provides both the right general definition of distributional convergence and the theoretical framework for finding limits. Billingsley's book covers both the abstract theory and the methods for applying it to stochastic processes.

The book under review is billed as a second edition of a text originally published in 1968. In the thirty plus years since, applications and theory of weak convergence have developed extensively, but the core material of the text is still basic and still makes a good introduction. In preparing a second edition, Billingsley has made major revisions, almost to the point of producing a different book. True, the basic sections reappear in recognizable form and the same pedagogical motivations remain intact, but some old material has been dropped, all the exposition has been reworked, and entirely new topics appear. In short, it has been thoroughly updated.

Billingsley's book is more textbook than monograph; it pays careful attention to exposition and conceptual understanding and includes problems. At the same time, it goes deeply and brings the reader to a sophisticated level. The treatment starts with basic theory for an abstract, separable metric space. After thoroughly exploring the weak convergence concept, it presents the important theorem of Prohorov, which gives a necessary and sufficient condition that a sequence of probability measures admit a weakly converging subsequence. These abstract results are then generalized to the two metric spaces that really matter for stochastic processes, the space C of continuous functions and the space D of right continuous functions with left limits. Each merits a separate chapter. The space C is endowed with the supremum norm metric and is the easier case to handle. Here Prohorov's theorem takes the form of uniform estimates on the modulus of continuity of a sample path. This result is used to give straightforward proofs of the existence of Brownian motion and of Donsker's invariance principle, which states that the processes Xn defined above indeed converge in distribution to Brownian motion, regardless of the precise probability distribution of the original steps. The supremum norm metric, which will not allow two paths with different jump times to be close, is no longer appropriate for the space D. Instead, a special topology called the Skorohod topology is used, which Billingsley describes in careful and explicit detail. He then derives the basic convergence criterion on D. For applications beyond Donsker's theorem, Billingsley focuses on central limit theorems for scaled random walks with dependent steps. He derives limit theorems for asymptotic behavior of lacunary trigonometric series and of the number of prime divisors in a sequence of integers, and theorems for scaled martingales and ergodic processes. Finally, a new chapter touches on useful complements: how the basic functional central limit theorem can be used to discuss convergence and approximation in a fixed probability space, and Strassen's functional version of the law of the iterated logarithm.

The first edition is known for its excellent and accessible exposition. The second edition carries on the tradition. The subject of weak convergence ought to be standard knowledge for all researchers in stochastic processes. Unfortunately, the entrance cost is high; it requires a good grounding in graduate measure and integration theory and basic point-set topology. However, Billingsley has a gift for clear, motivated exposition, and guides the novice well. An appendix provides a helpful review of the required facts about metric spaces. New tools are introduced carefully with plenty of discussion and examples. Important applications are introduced as soon as possible, illustrating utility of the abstract theory as it is being developed and before it overwhelms. Many proofs, already elegant in the first edition, have been burnished even further, and some of the tougher results, such as maximal inequalities or limit theorems for mixing process, have simpler, more insightful proofs. These improvements make it a pleasure to read, even for those familiar with the old book.

The applications in Billingsley's book have been updated in the second edition, but they still focus heavily on scaled random walks. Since the first edition was published, applications of weak convergence have extended dramatically in many areas of applied and theoretical stochastic processes: the martingale theory approach to Markov processes [SV, EK], large deviation theory [DE], approximate models in control and electrical engineering applications [K], high traffic limits of queuing networks, etc. Billingsley's book does not try to touch on these; he has even dropped a section on diffusion processes in the first edition. However, the fundamental theory in the spaces C and D behind all applications is the same. Because of its pedagogical virtues, I would recommend his book as a starting place to any student of the topic, whatever his or her applied interests ultimately are. For its elegance of presentation and its nice examples, it should appeal to the expert as well.

[DE] P. Dupuis and R.S. Ellis, A Weak Convergence Approach to the Theory of Large Deviations, John Wiley & Sons, New York, 1997.

[EK] S.N. Ethier and T.G. Kurtz, Markov Processes: Characterization and Convergence, John Wiley & Sons, New York, 1986.

[K] H.J. Kushner, Approximation and Weak Convergence Methods for Random Processes, MIT Press, Cambridge, 1984.

[SV] D.W. Stroock and S.R.S. Varadhan, Multidimensional Diffusion Processes, Springer-Verlag, New York, 1979.

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                                                                     -o-

The Fabric of Reality by David Deutsch

Penguin Books 1997

                                           (Reviewed by Haym Benaroya, Rutgers)

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This is a very exciting book by a theoretical physicist who proposes a worldview where some of the “strange” occurrences that are predicted by quantum mechanics are better understood. Nevertheless, this is not solely a book on quantum mechanics. This book presents the thesis that the fabric of reality rests on a synthesis of the theories of evolution, computation, epistemology, and quantum mechanics. At first sight, these appear to be nearly orthogonal pursuits. But it turns out, according to the author, that we need to consider and include all in a framework that has as its goal an explanation of our world.

Due to the quantum nature of matter, experiments show very strange, counter-intuitive results on how photons behave. In particular, photons, i.e., electrons, sometimes behave as particles and other times behave as waves. In addition, in the slit experiment, a single electron can appear to behave as a wave, showing interactions with other particles. Except that there are no other particles to interact with!

Such observations, the author concludes, provide us evidence that other universes exist that are parallel to ours, and all these universes together make up a “reality” called a multiverse. The multiverse is the infinity of universes that comprise reality. Some are weakly coupled, those where there are many similarities; others are not coupled at all where there is no similarity at all.

There is an interesting discussion about time machines and the paradoxes, a “knowledge paradox”, that time travel can lead to. For example, suppose I travel back in time with the complete works of Shakespeare to the time before Shakespeare had written his plays. I find Shakespeare and show him “his” plays. He then adopts them (there is no intent here to disparage Shakespeare by having him steal his own work), and publishes them. How is it possible, then, that the work was never really created but rather stolen from the future?

Deutsch makes the argument that if we were able to move “back in time”, what we would be in reality doing is moving to an earlier time in some weakly coupled universe, not to an earlier era in the current universe. Therefore, the paradoxes of time travel to the past cannot confront us. In the previous example, going back to the time of Shakespeare, we are providing a Shakespeare in another universe the writings of “our” Shakespeare. In effect, knowledge is being passed between closely coupled universes.

As part of his worldview, Deutsch makes the emphatic point that predicting what will happen is not the same as understanding why things happen. He also takes the holistic approach to explaining our environment, that is, taking the larger view rather than the usual reductionist views that is more common in science. The reductionist view explains things by developing theories about smaller and smaller building blocks. In this book, the view is put forward that evolution, computation, epistemology and quantum physics, together, provide an understanding of our reality. “Considered jointly, these four strands of explanation reveal a unified fabric of reality that is objective and comprehensible.”

The Fabric of Reality explains and connects many topics at the leading edge of current research and thinking, from quantum computers to time travel and from the physical limits of virtual reality to the ultimate fate of the universe. This book is suitable for scientist and lay person alike, for philosopher and science fiction reader, biologist and computer expert. Be prepared to see the views of establishment scientists taken to task. The book is optimistic about the prospects that we are close to a theory that provides an explanation of why things exist as they do. This book must be read carefully, because each paragraph is chock full of thought. In fact, after I finish writing this review, I am going back to re-read the whole book. I am sure there are dimensions of this multiverse view that I have missed. To be greatly enjoyed.

                                                                      -o-

                          Biographies of Four Mathematicians:
                   Hadamard, von Neumann, Ramanujan and Smale


                

                                                   (Reviewed by Haym Benaroya, Rutgers)

I received the four books discussed below from the publisher, The American Mathematical Society www.ams.org, at one time. (Two are jointly published with the London Mathematical Society.) My original intention was to review each separately, but realized that it would be an interesting exercise to do a “comparative” review. For those of you who read the endings of mysteries first, here is the short version of the reviews which follow: These mathographies, to repeat a phrase coined by Halmos in his autobiography, are all wonderful and enjoyable to read, but the books are as different as the mathematicians whose lives they recount.

The books reviewed here are:

Jacques Hadamard, A Universal Mathematician, by Vladimir Maz'ya and Tatyana Shaposhnikova, Linköping University - AMS | LMS, 1998, 574 pp., Softcover, ISBN 0-8218-1923-2.

John von Neumann: The Scientific Genius Who Pioneered the Modern Computer, Game Theory, Nuclear Deterrence, and Much More, by Norman Macrae - AMS, 1992, 406 pp., Hardcover, ISBN 0-8218-2064-8.

Ramanujan: Letters and Commentary, by Bruce C. Berndt, University of Illinois, Urbana, and Robert A. Rankin, University of Glasgow - AMS | LMS, 1995, 347 pp., Hardcover, ISBN 0-8218-0287-9.

Stephen Smale: The Mathematician Who Broke the Dimension Barrier, by Steve Batterson, Emory University - AMS, 2000, 306 pp., Hardcover, ISBN 0-8218-2045-1.

All these mathematicians are considered to be among the most creative of this (and the last) centuries. Nevertheless, they could not have had different lives. Hadamard lived to the age of 98, but Ramanujan lived to only 33, and was in poor health during the last few years of his life. Hadamard was born at the end of the US Civil War (1865) and died in the year of President Kennedy’s assassination (1963): A truly remarkable span of time especially when considering the changes in society and science, and the two world wars that he witnessed.

Von Neumann lived only into his fifties, and Smale is today in his seventieth year. Politically, the ideas and philosophy of von Karman and Smale are at opposite ends of the spectrum, the former was very conservative, and the latter was a member of the US communist party. Hadamard lived through the Dreyfus affair in the France of the late 1890’s. They were related by a distant marriage.

Hadamard, by virtue of his longevity and of being in France during the times when many of the foundations of modern mathematics were being laid, seems to have come into contact with anyone who was of any significance to science and mathematics. One of the pleasures of reading this book was finding out about many of the mathematicians of the last 150 years. I truly enjoyed leafing through the book, in advance of reading it, to see the pictures of all the famous mathematicians I only otherwise know by name and work.

In these stories there are tragic sides. Two of  Hadamard’s sons, one a volunteer and apparently more mathematically gifted (!) than his father, were killed in W.W.I. . A third son was killed in W.W.II. Another is, of course, the very short life of Ramanujan.

All the authors are mathematicians except Macrae, the author of von Neumann. This explains the lack of mathematics in his biography. Biographical writers are not usually trained in mathematics, and mathematicians do not usually write biographies. We are fortunate that the other biographies provide a flavor of these men’s lives, both personally and mathematically.

The books are very well written and engaging. I generally like looking through a book before reading it from the beginning. The problem was that, with all these books, I found myself drawn into the narrative and it was truly difficult to disengage.

Next, I would like to summarize each book individually, and then to conclude this discussion afterwards.

Hadamard

This book presents a fascinating story of the long life and great accomplishments of Jacques Hadamard (1865-1963), who was once called "the living legend of mathematics". As one of the last universal mathematicians, Hadamard's contributions to mathematics are landmarks in various fields. His life is linked with world history of the 20th century in a dramatic way. This work provides an inspiring view of the development of various branches of mathematics during the 19th and 20th centuries.

Part I of the book portrays Hadamard's family, childhood and student years, scientific triumphs, and his personal life and trials during the first two world wars. The story is told of his involvement in the Dreyfus affair and his subsequent fight for justice and human rights. Also recounted are Hadamard's worldwide travels, his famous seminar, his passion for botany, his home orchestra, where he played the violin with Einstein, and his interest in the psychology of mathematical creativity.

Hadamard's life is described in a readable and inviting way. The authors humorously weave throughout the text his jokes and the myths about him. They also movingly recount the tragic side of his life. Stories about his relatives and friends, and old letters and documents create an authentic and colorful picture. The book contains over 300 photographs and illustrations.

Part II of the book includes a lucid overview of Hadamard's enormous work, spanning over six decades. The authors do an excellent job of connecting his results to current concerns. While the book is accessible to beginners, it also provides rich information of interest to experts.

Von Neumann

Born in Budapest in 1903, John von Neumann grew up in one of the most extraordinary of scientific communities. From his arrival in America in the mid-1930s--with bases in Boston, Princeton, Washington, and Los Alamos--von Neumann pioneered and participated in the major scientific and political dramas of the next three decades, leaving his mark on more fields of scientific endeavor than any other scientist. Von Neumann's work in areas such as game theory, mathematics, physics, and meteorology formed the building blocks for the most important discoveries of the century: the modern computer, game theory, the atom bomb, radar, and artificial intelligence, to name just a few.

From the laboratory to the highest levels of government, this definitive biography gives us a behind-the-scenes look at the politics and personalities involved in these world-changing discoveries. Written more than 30 years after von Neumann's untimely death at age 54, it was prepared with the cooperation of his family and includes information gained from interviewing countless sources across Europe and America. Norman Macrae paints a highly readable, humanizing portrait of a man whose legacy still influences and shapes modern science and knowledge.

When I read a biography, whether about a mathematician or anyone else, I look forward to looking at many photos. This biography of von Neumann has no photos! A major disappointment. While the text is engaging, and generally well written, a more thorough editing job would have been appropriate.

Ramanujan
 
The letters that Ramanujan wrote to G. H. Hardy on January 16 and February 27, 1913, are two of the most famous letters in the history of mathematics. These and other letters introduced Ramanujan and his remarkable theorems to the world and stimulated much research, especially in the 1920s and 1930s. This book brings together many letters to, from, and about Ramanujan. The letters came from the National Archives in Delhi, the Archives in the State of Tamil Nadu, and a variety of other sources. Helping to orient the reader is the extensive commentary, mathematical and cultural, by Berndt and Rankin; in particular, they discuss in detail the history, up to the present day, of each mathematical result in the letters.

Containing many letters that have never been published before, this book will appeal to those interested in Ramanujan's mathematics as well as those wanting to learn more about the personal side of his life. Of all four books reviewed here, this one is the only that thoroughly intersperses the math with the biography. While this is more true to life, it does make reading more difficult for the lay reader. More difficult, but not impossible.

Smale

In 1957, Stephen Smale startled the mathematical world by showing that, in a theoretical sense, it is possible to turn a sphere inside out. A few years later, from the beaches of Rio, he introduced the horseshoe map, demonstrating that simple functions could have chaotic dynamics. His next stunning mathematical accomplishment was to solve the higher-dimensional Poincaré conjecture, thus demonstrating that higher dimensions are simpler than the more familiar three. In 1966 in Moscow, he was awarded the Fields Medal, the most prestigious prize in mathematics.

Smale's vision and influence extended beyond mathematics into two vastly different realms. In 1965 in Berkeley, he initiated a program with Jerry Rubin of civil disobedience directed at ending the Vietnam War. Moreover, as a mineral collector, he accumulated a museum-quality collection that ranks among the finest in the world. Despite these diverse accomplishments, Smale's name is virtually unknown outside mathematics and mineral collecting. One of the objectives of this book is to bring his life and work to the attention of a larger community. 

Concluding Thoughts

I wholeheartedly recommend all these books. While all can be read by interested lay people, there are differences. Von Neumann has no equations and would be easily read by anyone with an interest. Hadamard is written in two parts. The first part also contains no equations. Part II is a detailed mathematical exposition of the branches of mathematics where Hadamard made his contributions. Smale follows a similar approach with technical content placed in appendices. Ramanujan, except for historical portions, would be difficult for the non-mathematician to follow. Mathematics in interspersed throughout the biography. However, I still found enjoyable what I could understand.

<            All these books contained extensive references. Only Hadamard is, regrettably, in softcover. Otherwise, the productions are attractive and pleasant to work with. In this day of exorbitant prices, these are priced moderately at between $35 and $59.

                                                                        -o-

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                              Analytical Mechanics, by J.S. Török,
                                     Wiley Interscience, 2000

                                        (Reviewed by H. Baruh, Rutgers University)

This book compiles concepts from analytical dynamics into a concise text. The author begins with a discussion of Newtonian concepts.  Then, the basic concepts of Lagrangian mechanics are introduced. Lagrange's equations are derived and issues such as impulsive motion and motion integrals are discussed.  The next chapter deals with variational calculus.  Hamilton's principle is derived and Lagrange's equations are shown to be derivable from that principle, as well.  The author continues with the dynamics of rotating bodies, together with some qualitative analysis of gyroscopic motion.  The last two chapters are devoted to Hamiltonian systems and to basic stability theory. The author derives Hamilton's canonical equations, the Hamilton-Jacobi equation, and discusses the phase space. Then, stability of linear and nonlinear systems are discussed and methods are introduced to test for stability.  The book ends with three appendices that explain the various mathematical concepts used throughout the book.

While the author indicates that this book is suitable for an engineering course, the book seems more like a theoretical physics text, where the emphasis is more on particle mechanics and the subject material is seen as a springboard to more advanced concepts from physics, such as quantum theory. The book puts little emphasis on rigid body motion; there is little discussion of angular velocity in three dimensions, quantification of angular velocity, Lagrangian mechanics and three dimensional motion, nonholonomic systems, and impulse-momentum relations.  Constrained systems are considered only lightly. The material on the calculus of variations should have appeared before the sections on Lagrangian mechanics, this way the reader would get a better understanding of the concept of a variation.

One advantage of the book is that it contains a very large set of problems at the end of each chapter.The problems are interesting and well-posed, and solving a good number of them certainly enriches one's knowledge of dynamics.  However, this advantage is countered by the disadvantage that there are very few illustrative examples throughout the text.  While the writing is clear and easy to follow, the lack of examples make it difficult for the reader to grasp applications of the basic concepts.   Any faculty member teaching out of this book should solve as many examples as possible in the classroom.

The last two chapters of the book are usually found in more advanced texts and the subjects are usually covered in graduate level courses.   These chapters are well-written, they make interesting reading, and they can be used as a good source of references.

In conclusion, Analytical Mechanics appears more like a physics textbook (which, of course, is not a disadvantage for someone in a physics curriculum). I would recommend marketing this text to physics curricula.  The book is written clearly and is easy to read.  It suffers from a lack of examples in the text, as well as a lack of emphasis on three-dimensional rigid body dynamics.  On the other hand, the book makes a good reference text; a lot of information is presented very concisely.

                                                                        -o-

At Home in the Universe:
The Search for the Laws of Self-Organization and Complexity

Oxford University Press 1995>
by Stuart Kauffman

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(Reviewed by Haym Benaroya, Rutgers)

This is a very exciting and understandable book. The subtitle of the book: The Search for the Laws of Self-Organization and Complexity actually gives the reader the underlying thrust. The thesis is that life evolved due to a combination of two underlying realities: Darwinian evolution coupled with the tendency of complex systems to self-organize. This self-organization has as its components, the organization of autocatalytic (nonequilibrium chemical) systems into closed catalytic living molecular groups. These groups are dynamically stable but can evolve and mutate. The laws of natural selection govern such evolution. In addition, these living systems exist either near or at the border between chaotic and complex but ordered state spaces.

The book is written in a casual style, giving the reader the feel of actually engaging in conversation with the author. This book is not, however, only about evolution. Rather, at its heart is the discovery of the order that lies deep within the most complex of systems, from the origin of life, to the workings of giant corporations, to the rise and fall of great civilizations. Kauffman contends that complexity itself triggers self-organization, what he calls “order for free,” and that if enough different molecules pass a certain threshold of complexity, they begin to self-organize into a new entity: a living cell. In turn, Kauffman extends this new paradigm to economic and cultural systems, showing that all may evolve according to similar general laws.

Besides the excitement of learning this revolutionary view about how “all this evolution took place in such a short time,” the reader is introduced to relatively simple example systems that demonstrate the concept and its workings.  This reader is not versed in chemistry or biology and found it possible to follow the arguments (while being impressed by the long biochemical words). Those who wish to be exposed to a more rigorous monograph on this subject need only look to Kauffman’s earlier work, The Origins of Order: Self-Organization and Selection in Evolution. It would be a wonderful follow-on to At Home in the Universe.

As one who has some background in dynamics, seeing how complexity and chaos theories have an impact on the evolution of life on Earth is truly a profound experience. In this time of doubt and argument amongst many that life could have evolved to its amazing current complexity in the time available since Earth became hospitable to life, this book presents an important argument on how it could have happened. As Kauffman puts it, rather than We the Improbable, referring to life on Earth, the reality is: We the Expected. The evolution of life on Earth was a likely, highly probable, event. Darwin’s Evolution worked hand-in-hand with Complexity and Self-Organization to build a rich, diverse and robust ecosystem.

At Home in the Universe is concluded on a very philosophical and, I think, optimistic note. The author observes the emergence of a global civilization, the ultimate complex system of human experience, and expresses the hope (belief?) that the result of the mixing of humanity will result in completely new cultures. The last section, “Reinventing the Sacred,” states that “awe and respect have become powerfully unfashionable in our confused postmodern society.” Kauffman humbly concludes that his is a proposed thesis; he is gratified that it seems to fit with the reality around us. “We are all part of the process, created by it, creating it.”

Be awed. Read this book!