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Ubiquity par [Buchanan, Mark]
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Longueur : 290 pages Word Wise: Activé Langue : Anglais

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Descriptions du produit

Extrait

Politics is not the art of the possible.
It consists in choosing between
the disastrous and the unpalatable.

--John Kenneth Galbraith

History is the science
of things which are never repeated.

--Paul Valéry

It was 11 a.m. on a fine summer morning in Sarajevo, June 28, 1914, when the driver of an automobile carrying two passengers made a wrong turn. The car was not supposed to leave the main street, and yet it did, pulling up into a narrow passageway with no escape. It was an unremarkable mistake, easy enough to make in the crowded, dusty streets. But this mistake, made on this day and by this driver, would disrupt hundreds of millions of lives, and alter the course of world history.

The automobile stopped directly in front of a nineteen-year-old Bosnian Serb student, Gavrilo Princip. A member of the Serbian terrorist organization Black Hand, Princip couldn't believe his luck. Striding forward, he reached the carriage. He drew a small pistol from his pocket. Pointed it. Pulled the trigger twice. Within thirty minutes, the Austro-Hungarian Archduke Franz Ferdinand and his wife Sophie, the carriage's passengers, were dead. Within hours, the political fabric of Europe had begun to unravel.

In the days that followed, Austria used the assassination as an excuse to begin planning an invasion of Serbia. Russia guaranteed protection to the Serbs, while Germany, in turn, offered to intercede on Austria's behalf should Russia become involved. Within just thirty days, this chain reaction of international threats and promises had mobilized vast armies and tied Austria, Russia, Germany, France, Britain, and Turkey into a deadly knot. When the First World War ended five years later, ten million lay dead. Europe fell into an uncomfortable quiet that lasted twenty years, and then the Second World War claimed another thirty million. In just three decades, the world had suffered two engulfing cataclysms. Why? Was it all due to a chauffeur's mistake?

On the matter of the causes and origins of the First World War, of course, almost nothing has been left unsaid. If Princip touched things off, to the British historian A.J.P. Taylor the war was really the consequence of railway timetables, which locked nations into a sequence of military preparations and war declarations from which there was no escape. The belligerent states, as he saw it, "were trapped by the ingenuity of their preparations." Other historians point simply to German aggression and national desire for expansion, and suggest that the war was inevitable once Germany had become unified under Bismarck a half century earlier. The number of specific causes proposed is not much smaller than the number of historians who have considered the issue, and even today major new works on the topic appear frequently. It is worth keeping in mind, of course, that all this historical "explanation" has arrived well after the fact.

In considering how well we understand the natural rhythms of human history, and in judging how able we are nowadays to perceive even the rough outlines of the future, it is also worth remembering that the century preceding 1914 had been like a long peaceful afternoon in European history, and that to historians of the time the wars seemed to erupt like terrifying and inexplicable storms in a cloudless sky. "All the spawn of hell," the American historian Clarence Alvord wrote after the First World War, "roamed at will over the world and made of it a shambles. . . . The pretty edifice of . . . history, which had been designed and built by my contemporaries, was rent asunder. . . . The meaning we historians had read into history was false, cruelly false." Alvord and other historians thought they had discerned legitimate patterns in the past, and had convinced themselves that modern human history would unfold gradually along more or less rational lines. Instead, the future seemed to lie in the hands of bewildering, even malicious forces, preparing unimaginable catastrophes in the dark.

The First World War, the war sparked by "the most famous wrong turning in history," is the archetypal example of an unanticipated upheaval in world history, and one might optimistically suppose that such an exceptional case is never likely to be repeated. With the aid of hindsight, many historians now believe they understand the larger forces that caused the world wars of the twentieth century, and that we can once again see ahead with clear vision. But Alvord and his colleagues had similar confidence a century ago. What's more, few of us--professional historians included--seem any wiser when it comes to the present.

In the mid-1980s, the Union of Soviet Socialist Republics had existed for nearly three-quarters of a century, and it stood as a seemingly permanent fixture on the world stage. At that time, there were palpable fears in the United States that the U.S.S.R. was way ahead militarily, and that only with a concerted effort could the United States even stay competitive. In 1987, one would have had to scour the journals of history and political science to find even a tentative suggestion that the U.S.S.R. might collapse within half a century, let alone in the coming decade. Then, to everyone's amazement, the unthinkable became a reality--in just a few years.

In the wake of the U.S.S.R.'s unraveling, some historians leaped to another conclusion. Democracy seemed to be spreading over the globe, binding it up into one peaceful and lasting New World Order--the phrase favored, at least, by politicians in the West, who happily proclaimed the final victory of democracy (and capitalism) over communism. Some writers even speculated that we might be approaching "the end of history," as the world seemed to be settling into some ultimate equilibrium of global democracy, the end result of a centuries-long struggle for the realization of a deep human longing for individual dignity. Just a few years later, in what was then Yugoslavia, war and terrible inhumanity once again visited Europe. A momentary setback? Or the first ominous sign of things to come?

No doubt historians can also explain quite convincingly--though in retrospect, of course--why these events unfolded as they did. And there is nothing wrong with this kind of explanation; it is in the very nature of history that thinking and explanation must always proceed backwards. "Life is understood backwards," as Søren Kierkegaard once expressed the dilemma, "but must be lived forwards." And yet this need to resort always to explanations after the fact also underlines the seeming lack of any simple and understandable patterns in human affairs. In human history, the next dramatic episode, the next great upheaval, seems always to be lurking just around the corner. So despite their aim to find at least some meaningful patterns in history, it is probably true that many historians sympathize with the historian H. A. L. Fisher, who in 1935 concluded:

Men wiser and more learned than I have discerned in history a plot, a rhythm, a predetermined pattern. These harmonies are concealed from me. I can see only one emergency following upon another . . . and only one safe rule for the historian: that he should recognize in the development of human destinies the play of the contingent and the unforeseen. . . . The ground gained by one generation may be lost by the next.

Having read this far, you may be surprised to learn that this book is about ideas that find their origin not in history but in theoretical physics. It may seem decidedly odd that I have begun by recounting the beginning of the last century's major wars, and by trumpeting the capricious and convulsive character of human history. There is nothing new in the recognition that history follows tortuous paths, and that it has forever made a mockery of attempts to predict its course. My aim, however, is to convince you that we live in a special time, and that new ideas with a very unusual origin are beginning to make it possible to see why history is like it is; to see why it is and even must be punctuated by dramatic, unpredictable upheavals; and to see why all past efforts to perceive cycles, progressions, and understandable patterns of change in history have necessarily been doomed to failure.

A Faulty Peace

One may suspect that human history defies understanding because it depends on the unfathomable actions of human beings. Multiply individual unpredictability a billion times, and it is little wonder that there are no simple laws for history--nothing like Newton's laws, for instance, that might permit the historian to predict the course of the future. This conclusion seems plausible, and yet one should think carefully before leaping to it. If human history is subject to unpredictable upheavals, if its course is routinely and drastically altered by even the least significant of events, this does not make it unique as a process. In our world, these characteristics are ubiquitous, and it is just dawning on a few minds that there are very deep reasons for this.

The city of Kobe is one of the gems of modern Japan. It lies along the southern edge of the largest Japanese island of Honshu, and from there its seaport--the world's sixth largest--handles each year nearly a third of all Japan's import and export trade. Kobe has excellent schools, and its residents bask in what seems to be a haven of environmental stability. The city has good reason to call itself an "urban resort":peaceful sunrises have for centuries given way to bright, warm afternoons, which have in turn slipped into cool, tranquil evenings. If visiting Kobe, you would never guess that just beneath your feet invisible forces were preparing to unleash unimaginable violence. Unless, of course, you happened to be there at 5:45 a.m., January 17, 1995, when the calm suddenly fell to pieces.

At that moment, at a location just off the Japanese mainland, twenty kilometers southwest of Kobe, a few small pieces of rock in the ocean floor suddenly crumbled. In itself, this was unremarkable; minor rearrangements of the Earth's crust happen every day in response to the stresses that build up slowly as continental plates, creeping over the planet's surface, rub against one another. But this time, what started as a minor rearrangement did not end up that way. The crumbling of those first few rocks altered the stresses on others nearby, causing them also to break apart. Farther down the line, still others followed suit, and in just fifteen seconds the earth ripped apart along a line some fifty kilometers long. The resulting earthquake shook the ground with the energy of a hundred nuclear bombs, ruining every major road or rail link near Kobe and, in the city itself, causing more than a hundred thousand buildings to tilt or collapse. It sparked raging fires that took a week to control, and rendered inoperable all but 9 of the 186 berths in Kobe's port. Ultimately, the devastation killed five thousand people, injured thirty thousand, and left three hundred thousand homeless.

For centuries the area around Kobe had been geologically quiet. Then, in just a few seconds, it exploded. Why?

Japan is known for its earthquakes. A quake releasing ten times as much energy leveled the city of Nobi in central Japan in 1891, and others struck in 1927, 1943, and 1948 at other locations. The intervals between these great earthquakes--thirty-five, sixteen, and five years--hardly form a simple, predictable sequence, as is typical of earthquakes everywhere. If the historian H. A. L. Fisher failed to see in history "a plot, a rhythm, a predetermined pattern," then so too have geophysicists failed utterly, despite immense effort, to discern any simple pattern in the Earth's seismic activity.

Modern scientists can chart the motions of distant comets or asteroids with stunning precision, yet something about the workings of the Earth makes predicting earthquakes extremely difficult, if not altogether impossible. Like the fabric of international politics, the Earth's crust is subject to sporadic and seemingly inexplicable cataclysms.

The Great Burnout

Not far to the west of Wyoming's vast Bighorn Basin, the wild and unrestrained landscape of Yellowstone National Park climbs into the Rockies. Immense forests of aspen and lodgepole pine clothe the mountains like a soft fabric, hiding black bears and grizzlies, moose, elk, deer, and innumerable species of birds and squirrels, all thriving in the seemingly pristine wilderness. Here and there a great rocky dome bursts out of the pines and towers over the park like a timeless sentinel. This is America's most beautiful natural park, set aside for protection back in 1872, and now the holiday destination of more than a million visitors each year.

But if Yellowstone is a place of almost unfathomable peace, it is also, sporadically, a place of terrific, incendiary violence.

Lightning sparks several hundred fires within the park every year. Most burn less than an acre, or maybe a few acres before dying out, while others carry on to destroy a few hundred or, far more rarely, a few thousand. As of 1988, even the largest fire ever recorded, in 1886, had burned only twenty-five thousand acres. So late in June of 1988, when a lightning bolt from a summer thunderstorm sparked a small fire near Yellowstone's southern boundary, no one was unduly alarmed. The fire was named the Shoshone, and the Forest Service began monitoring its progression. Within a week, storms had ignited a couple of other fires elsewhere in the park, and yet there was still no cause for concern. On July 10, when a brief rain fell, there were a handful of fires still smoldering, but all seemed well in hand and likely to burn out in the coming weeks. It didn't happen that way.

Whether it was the unusually dry conditions or the persistent winds, no one can really say, but by the middle of July the fires had only become bigger. "Up until then, with the fires," a National Park Service spokeswoman later recalled, "it was business as usual." But on July 14, a fire given the name Clover spread to forty-seven hundred acres, and another called the Fan grew to cover twenty-nine hundred acres. Four days later yet another fire, sparked in an area known as Mink Creek, had exploded to cover thirteen thousand acres, and forest managers were beginning to see things that no expert had envisaged. The Shoshone fire suddenly gathered new life, racing to consume more than thirty thousand acres in just a few days, and by August some two hundred thousand acres of the park either had burned or were burning; on all fronts flames were advancing five to ten miles each day under a smothering blanket of smoke ten miles high.

Over the next two months, more than ten thousand firefighters from across the country, using 117 aircraft and more than a hundred fire engines, struggled ineffectually as the blaze swept through the park. Eventually the flames consumed 1.5 million acres and more than $120 million in federal firefighting money, and lost momentum and dwindled only with the coming of the first snow in autumn. Somehow, from one or several insignificant bolts of lightning an unstoppable inferno had emerged that made the previous worst fire in the history of Yellowstone look like a backyard barbecue. What made this one so bad? And why didn't anyone see it coming?


From the Hardcover edition.

Revue de presse

“Buchanan succeeds where others fail. . . . [He] is able to communicate this novel way of thinking without compromising scientific integrity.”—New Scientist

“I grabbed this book and turned the pages. Does Buchanan get it right? Does he really understand how this might change the way we look at the world? He does. This is the book I wish I had written.”
—Per Bak, author of How Nature Works

“Ubiquity explains better than any previous book why many fields of the natural world and human life are unpredictable.”
Financial Times (London)

“There are many subtleties and twists in the story to which we shall come later in this book, but the basic message, roughly speaking, is simple: The peculiar and exceptionally unstable organization of the critical state does indeed seem to be ubiquitous in our world. Researchers in the past few years have found its mathematical fingerprints in the workings of all the upheavals I’ve mentioned so far, as well as in the spreading of epidemics, the flaring of traffic jams, the patterns by which instructions trickle down from managers to workers in an office, and in many other things. At the heart of our story, then, lies the discovery that networks of things of all kinds—atoms, molecules, species, people, and even ideas—have a marked tendency to organize themselves along similar lines. On the basis of this insight, scientists are finally beginning to fathom what lies behind tumultuous events of all sorts, and to see patterns at work where they have never seen them before.”
—from the Introduction

Détails sur le produit

  • Format : Format Kindle
  • Taille du fichier : 1441 KB
  • Nombre de pages de l'édition imprimée : 290 pages
  • Pagination - ISBN de l'édition imprimée de référence : 060960810X
  • Editeur : Broadway Books; Édition : 1 Amer ed (23 avril 2002)
  • Vendu par : Amazon Media EU S.à r.l.
  • Langue : Anglais
  • ASIN: B000RH0DZS
  • Synthèse vocale : Activée
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  • Composition améliorée: Non activé
  • Moyenne des commentaires client : 5.0 étoiles sur 5 2 commentaires client
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Format: Broché Achat vérifié
Ubiquity est un livre étrange et fascinant, à la frontière de plusieurs disciplines. Il s'agit d'une suite d'exemples concrets (par exemple les feux de forêts), racontés à l'aune de l'analyse systémique, actions/réactions, etc... En fil conducteur du livre, la conclusion omniprésente que le hasard mène le monde et qu'il n'est pas utile de mettre en place des modèles prédictifs qui ne peuvent rien prédire. Un seul bémol, le livre n'a pas une chute à la hauteur des autres chapitres, il s'arrête juste, c'est un peu dommage.
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Un livre passionnant, qui touche à de nombreux sujets autour d'un thème centrale : les systèmes instables et l'état critique.
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Amazon.com: HASH(0x87f88f00) étoiles sur 5 59 commentaires
72 internautes sur 73 ont trouvé ce commentaire utile 
HASH(0x87f91bd0) étoiles sur 5 A clear presentation of a crucial idea 23 juin 2003
Par Robert Adler - Publié sur Amazon.com
Format: Broché
Who hasn't wondered why catastrophes happen, and if they can be predicted or avoided? Economists and investors try to understand why markets crash, seismologists struggle to understand and predict great earthquakes, and historians speculate why empires crumble and global cataclysms such as the First and Second World Wars occur.
Physicist and science journalist Mark Buchanan brings the science of what he calls "historical physics"--the study of systems that are far from equilibrium and, as he puts it poised "on the knife edge of instability" to bear on these questions.
He describes a much-studied model of such catastrophe-prone systems, a simple sandpile. Build a sandpile by dropping one grain at a time on the top of the heap. It will eventually reach a critical state at which a grain can either make the pile a bit taller or start an avalanche, small or large. Scientists experimenting with real and virtual sandpiles have observed several important regularities:
1. The time between avalanches is extremely variable, making it essentially impossible to predict when the next avalanche will occur.
2. The size of avalanches is also extremely variable, making it essentially impossible to predict whether the next avalanche will be tiny or huge.
3. A big avalanche doesn't need a big cause; one grain can trigger a sandpile-flattening event.
4. Avalanche sizes follow what mathematicians call a power law. What that means is that large events happen less frequently than small ones according to a fixed ratio. For sandpiles the frequency goes down by a factor of 2.14 for each doubling of avalanche size. For earthquakes the frequency goes down by a factor of four for each doubling of released energy.
5. Any process that follows a power law shows two key features. The events are "scale invariant," meaning that no particular size of event is favored. And large events--big avalanches, 8.0 earthquakes, "1000-year floods" and many other kinds of catastrophic events occur far more frequently than common sense would suggest.
We tend to assume that events distribute themselves along the familiar normal curve--like height, weight, IQ scores, etc. These distributions do have a favored scale--most people cluster around the average height, weight, or IQ, while the number of people with extremely low or extremely high scores is very small.
Buchanan shows that many events that greatly impact our lives represent changes in sandpile-like systems, and so are not just hard to predict, but inherently unpredictable. The one thing that can be predicted is that huge events will occur far more often than our intuition prepares us for.
Many natural events follow power laws, including earthquakes, forest fires, floods and the mass extinctions that have punctuated the history of life on earth. And many human events also show these regularities, including traffic jams, market crashes, the collapse of nations and empires, and wars.
Buchanan's presentation of these regularities and their implications is well reasoned, well documented and well written. Read it for yourself, and see if the ideas he presents don't help you to understand what seems to be a profound pattern that underlies many of the events that shape and shake our lives.
Robert Adler, author of Science Firsts: From the Creation of Science to the Science of Creation (Wiley & Sons, September 2002).
37 internautes sur 37 ont trouvé ce commentaire utile 
HASH(0x87f91c24) étoiles sur 5 From The Innovation Road Map Magazine 12 mai 2005
Par Paul A. Schumann Jr. - Publié sur Amazon.com
Format: Broché Achat vérifié
This is not a hard book to read, but it is difficult to integrate into the way you look at the world. Mark Buchanan is a science writer who has worked on the editorial staff of Nature and as a features editor New Scientist. In this book he is writing about the development of a growing field of physics - complexity. Complexity is chaos in critical states. A critical state exists in a system that is not in equilibrium. You may have heard of the "butterfly effect". That is, there is a possibility that a butterfly flapping its wings in South America can cause a storm in Europe weeks later. However, that same butterfly can flap all in wants inside a closed balloon with no effects, other than maybe slightly increasing the temperature of the air in the balloon. The air inside the balloon is in equilibrium, even though the molecules exhibit chaotic behavior. The atmosphere is in a critical, i.e. non-equilibrium, state. A small perturbation somewhere can lead to very big changes.

If the air inside the balloon is in equilibrium, its past, present and future are all the same. It has no "history". When things are in non-equilibrium, history matters since what happens now can never be washed away but affects the entire course of the future.

The applications of this model extend from the piling of grains of sand in an hourglass to economics.

"Despite what scientists had previously believed, might the critical state in fact be quite common? Could riddling lines of instability of a logically equivalent sort run through the Earth's crust, for example, through forests and ecosystems, and perhaps even through the somewhat more abstract "fabric" of our economics? Think of those first few crumbling rocks near Kobe, or that first insignificant dip in prices that triggered the stock market crash of 1987. Might these have been "sand grains" acting at another level? Could the special organization of the critical state explain why the world at large seems so susceptible to unpredictable upheavals?

A decade of research by hundreds of other physicists has explored this question and taken the initial idea much further. There are many subtleties and twists in the story to which we shall come later in this book, but the basic message, roughly speaking, is simple: The peculiar and exceptionally unstable organization of the critical state does indeed seem to be ubiquitous in our world. Researchers in the past few years have found its mathematical fingerprints in the workings of all the upheavals I've mentioned so far, as well as in the spreading of epidemics, the flaring of traffic jams, the patterns by which instructions trickle down from managers to workers in an office, and in many other things. At the heart of our story, then, lies the discovery that networks of things of all atoms, molecules, species, people, and even ideas have a marked tendency to organize themselves along similar lines. On the basis of this insight, scientists are finally beginning to fathom what lies behind tumultuous events of all sorts, and to see patterns at work here where they have never seen them before."

The mathematical models of this science don't really exist yet, and may never exist. We have empirical observations and we have games. The empirical data suggests that all these phenomena follow a power curve, and all with roughly the same shape. For example, looking at earthquakes, as the strength of the earthquake doubles, the frequency of occurrence drops by one fourth. This simple rule seems to apply to many examples.

So what does this have to do with creativity, strategy, leadership and innovation in organization? Well, I'm not sure yet. My intuition tells me that this is very important to those concepts. It may help us understand the frequency of occurrence of breakthrough ideas and innovation. It may help explain why some innovations cause such change and others do not. It may help produce better strategies to deal with chaotic and unstable markets. And, it may provide lessons for leaders in chaotic times.
30 internautes sur 30 ont trouvé ce commentaire utile 
HASH(0x87f91f00) étoiles sur 5 One of the best 28 mai 2006
Par B. B. Jenitez - Publié sur Amazon.com
Format: Broché
This is the book that I would like to have written. Although being a popular account, it is scientifically accurate and carefull in its suggestions, always informing the reader what is consolidated science and what is scientific speculation.
In contrast to a previous review, I have read all the pages of this book. Since I am a physicist working in this very subject (self-organized criticality), I probably can say that if someone use the example of a Gaussian (bell shaped curve) to illustrate that the power laws discussed in the book are trivial, well, this person have not understood anything.
Gaussians have exponential decays, so they predict that very larg events (catastrophes) will occur with vanishing probability. For example, the heigh of people is distributed as a Gaussian. What is the probability of finding a 3 meter person?
Zero.
Distributions wich have power law tails, depending on the power exponent, may have no well defined variance or even average value. This means that there is no "average" earthquake, and that very big earthquakes (or other cathastrophes) are not "acts of God" but have a no desprezible chance of occur due to simple chain reactions of events.
I have introduced my students to ideas like critical states and modern physical thinking by using this book. So, I can recommend it to any reader without reserve. The emphasis by the author that critical chain reactions of events must be accounted by any view of History and Society is an important mind tool in our increasing interconnected (and, because it, prone to global chain reactions) world.
36 internautes sur 38 ont trouvé ce commentaire utile 
HASH(0x87fa0444) étoiles sur 5 The Physics of History 24 octobre 2001
Par Sergio Da Silva - Publié sur Amazon.com
Format: Relié
CERTAIN complex systems, under certain circumstances, have been discovered to behave in mathematically simple, similar ways. In 'critical states', there is no reason to look for specific causes of great events. The smallest force can have gigantic effects and sudden upheavals can strike seemingly out of nowhere. The approximate frequency of such upheavals can be predicted, but not when they will happen or what size they will be.
Mark Buchanan's book reviews the current work on the subject to highlight a deep similarity between the upheavals that affect our lives in both physical and human systems. The book warmly communicates this novel way of thinking without compromising scientific integrity. This is made possible because the author is not only a science writer but also a physicist.
Buchanan starts by discussing the principle of ubiquity which is that one should focus on the simplest mathematical game belonging to a same universal class. Details are not important in deciding the outcome because things in a critical state have no inherent typical scale in either time or space. The important issue which this book highlights is that in a critical state, something known as a `power law' comes into play to reveal a hidden order and simplicity behind complexity. A power law means that there is no such thing as a normal or typical event, and that there is no qualitative difference between the larger and smaller fluctuations.
Buchanan illustrates this with the following example. If one takes a handful of rice (or sand) and drops the grains one by one on to a table top, a pile of rice is built soon. The pile will not grow taller for ever, though. Eventually the addition of one more grain will cause an avalanche. Such a grain is only special because it happened to fall in the right place at the right time. The addition of a single grain may have no effect, precipitate a small avalanche, or collapse the whole structure. One can predict the likely frequency of the avalanches, but not when they will happen or what size each will be. It may come as no surprise that big avalanches occur less frequently than small ones. What is surprising is that there is a power law: each time the size of an avalanche of rice grains is doubled, it becomes twice as rare.
The book reveals that power laws have been discovered for events ranging from forest fires and earthquakes to mass extinctions and stock market crashes. This is the power law for forest fires: when the area covered by a fire is doubled, it becomes about 2.48 times as rare. If the size of an earthquake is doubled, these quakes become four times less frequent. The bigger the quake, the rarer it is. The distribution is scale invariant, that is, what triggers small and large quakes is precisely the same. A power law for the distribution of extinction sizes (that fits the fossil record well) happens to be identical to that for earthquakes: every time the size of an extinction (as measured by the number of families of species that become extinct) is doubled, it becomes four times as rare. Interestingly for economists, a power law has been discovered in the stock market. Price fluctuations in the Standard & Poor 500 stock index were found to become about sixteen times less likely each time the size is doubled.
Not only that, but other human-influenced events come under the same 'natural' laws. Wars seem to strike with the same statistical pattern as do earthquakes or avalanches in the rice-pile game. What is more, the forest-fire game seems to capture the crucial elements of the way that conflicts spread. A war may begin in a manner similar to the ignition of a forest. Statistics over five centuries have uncovered a power law for wars. Every time the number of deaths is doubled, wars of that size become 2.62 times less common. Such a power law implies that when a war starts out no one knows how big it will become. There seem to be no special conditions to trigger a great conflict. Likewise revolutions are moments that got lucky...
This view of history will make no one feel any safer or happier. After all, wars and revolutions could strike out of nowhere. But it is comforting that the tumultuous course of mankind need not be the outcome of human madness, but of simple mathematics. At the end of the book, one feels excitement about ubiquity. It seems that a profound breakthrough in our understanding of history is coming up. I experienced it. Join me. Read the book.
8 internautes sur 8 ont trouvé ce commentaire utile 
HASH(0x87fa045c) étoiles sur 5 Certainly plausible and explains a lot 19 août 2002
Par Atheen - Publié sur Amazon.com
Format: Relié
Buchanan's book Ubiquity is a fascinating volume on self organizing criticality. It bears a striking resemblance to Per Bak's book How Nature Works, and Bak's research is cited a number of times throughout the text. As with the Bak work, Buchanan's covers a wide variety of subjects from wars to stock market fluctuations. Of particular interest to me was the discussion of evolution and the episodic character of mass extinctions, since I've read a number of books on the subject of the K-T boundary extinction.
Like Bak, Buchanan points out that much that appears to have historical significance and specific causation, while it makes for good story telling, has little predictive value about it. He uses Bak's sandpile experiments to illustrate the futility of such efforts by creating a "Sandman's view" of catastrophe (pp. 179-180). He imagines a catastrophic sand slide from the point of view of a tiny survivor to whom events seem to have been "due" to negligence on the part of the individuals responsible for a steep area. From the point of view of the sandpile, though, the information required for such control would have to be staggeringly large and nearly perfect in order to have predicted the slide and its effects. Had some minute change to the pile been possible at the putative disaster site, a similar slide could have occurred elsewhere. Then the caretakers of the sandpile would have been blamed for causing a disaster rather than preventing one. One can see in this parable why politicians in the real world tend to seek their own ultimate good rather than that of their constituents or of the environment itself. The vagaries of prediction caused by the intertwining of particulars and the vastness of the data involved put such individuals in impossible positions. They are either guilty of not preventing or of causing various negative outcomes if they are unfortunate or praised for positive outcomes if fortunate. As the author points out in a quote of John Galbraith, "Politics is not the art of the possible. It consists in choosing between the disastrous and the unpalatable (p. 1)."
The key point of the book seems to be that many systems are organized on the critical edge between instability and stability. Life itself may owe its very existence to that fact. Because of this poised-on-the-edge characteristic, small events may cascade in such a way as to produce major changes: a new value for stocks, a massive extinction that creates new opportunities for remaining species, a redistribution of power among nations, etc. Which outcomes occur and when, however, are not subject to predictive formulae, even though they may seem ideally suited to it. If even extreme events are the results of myriads of small, seemingly unimportant events-sort of the butterfly in Japan fluttering its wings concept-then there are no means by which catastrophic events can be predicted any more than smaller ones can be. According to the author, while there seems to be a mathematical frequency with which incidents of different magnitudes occur, there is no way of divining when a specific outcome of a given magnitude will actually occur, nor are the consequences should such an event be forestalled. This has implications for events meaningful to human beings: wars, the stock market peaks and valleys, even extinction events. For Buchanan, history itself may arise by virtue of natural resolutions of unstable systems of whatever kind.
After reading the author's discussion of the Gutenberg-Richter power law and the scale invariance of some systems, it occurred to me that the end of the world scenario presented by Carl Sagan in his book Cosmos-and credited to an earlier researcher-may fall into this category. In that volume, a chart had been created that plotted murder (private war) to the total destruction of mankind against a time line, finding that total annihilation should occur a few years after the year 2000. (It was expected closer to mid 21st century, but the original author had not factored in the destructive power of nuclear war. Later individuals did and produced a chart that suggested armageddon would be around 2010). While the ultimate war may well occur, if Bak and Buchanan are correct, it might not be due to either predictable or controllable factors, and it will probably not occur on any clear cut timetable like that suggested in Cosmos.
An amazingly interesting book full of concepts that, however theoretical, are certainly plausible and explain a lot about our world.
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