Sunday, February 27, 2011

Freeman Dyson's Review of a James Gleick Book

The NY Review of Books has a wonderful review of James Gleick's new book The Information: A History, a Theory, a Flood written by one of my favourite mathematicians, Freeman Dyson. Here are some key bits:
The consequences of the information flood are not all bad. One of the creative enterprises made possible by the flood is Wikipedia, started ten years ago by Jimmy Wales. Among my friends and acquaintances, everybody distrusts Wikipedia and everybody uses it. Distrust and productive use are not incompatible. Wikipedia is the ultimate open source repository of information. Everyone is free to read it and everyone is free to write it. It contains articles in 262 languages written by several million authors. The information that it contains is totally unreliable and surprisingly accurate. It is often unreliable because many of the authors are ignorant or careless. It is often accurate because the articles are edited and corrected by readers who are better informed than the authors.

Jimmy Wales hoped when he started Wikipedia that the combination of enthusiastic volunteer writers with open source information technology would cause a revolution in human access to knowledge. The rate of growth of Wikipedia exceeded his wildest dreams. Within ten years it has become the biggest storehouse of information on the planet and the noisiest battleground of conflicting opinions. It illustrates Shannon’s law of reliable communication. Shannon’s law says that accurate transmission of information is possible in a communication system with a high level of noise. Even in the noisiest system, errors can be reliably corrected and accurate information transmitted, provided that the transmission is sufficiently redundant. That is, in a nutshell, how Wikipedia works.
I love the idea of bottom-up knowledge. Too much of our life is controlled by top-down autocrats busy trying to mold us to fit their version of what we should be ("proper" citizens, "dutiful" servants, patient and loyal consumers).

And Dyson catches the joys of science:
The information flood has also brought enormous benefits to science. The public has a distorted view of science, because children are taught in school that science is a collection of firmly established truths. In fact, science is not a collection of truths. It is a continuing exploration of mysteries. Wherever we go exploring in the world around us, we find mysteries. Our planet is covered by continents and oceans whose origin we cannot explain. Our atmosphere is constantly stirred by poorly understood disturbances that we call weather and climate. The visible matter in the universe is outweighed by a much larger quantity of dark invisible matter that we do not understand at all. The origin of life is a total mystery, and so is the existence of human consciousness. We have no clear idea how the electrical discharges occurring in nerve cells in our brains are connected with our feelings and desires and actions.

Even physics, the most exact and most firmly established branch of science, is still full of mysteries. We do not know how much of Shannon’s theory of information will remain valid when quantum devices replace classical electric circuits as the carriers of information. Quantum devices may be made of single atoms or microscopic magnetic circuits. All that we know for sure is that they can theoretically do certain jobs that are beyond the reach of classical devices. Quantum computing is still an unexplored mystery on the frontier of information theory. Science is the sum total of a great multitude of mysteries. It is an unending argument between a great multitude of voices. It resembles Wikipedia much more than it resembles the Encyclopaedia Britannica.
I love the great "democratic" thrusts of our age: science, democratic governance, popular culture, Wikipedia, etc. These are expressions of individuals that rise up and catch wind if enough people are attracted, or they can fail -- like democracy in Germany in 1933 -- if not enough people are willing to stand up for individual rights and individual beliefs.

And this bit shows Dyson's great optimism:
The explosive growth of information in our human society is a part of the slower growth of ordered structures in the evolution of life as a whole. Life has for billions of years been evolving with organisms and ecosystems embodying increasing amounts of information. The evolution of life is a part of the evolution of the universe, which also evolves with increasing amounts of information embodied in ordered structures, galaxies and stars and planetary systems. In the living and in the nonliving world, we see a growth of order, starting from the featureless and uniform gas of the early universe and producing the magnificent diversity of weird objects that we see in the sky and in the rain forest. Everywhere around us, wherever we look, we see evidence of increasing order and increasing information. The technology arising from Shannon’s discoveries is only a local acceleration of the natural growth of information.

The visible growth of ordered structures in the universe seemed paradoxical to nineteenth-century scientists and philosophers, who believed in a dismal doctrine called the heat death. Lord Kelvin, one of the leading physicists of that time, promoted the heat death dogma, predicting that the flow of heat from warmer to cooler objects will result in a decrease of temperature differences everywhere, until all temperatures ultimately become equal. Life needs temperature differences, to avoid being stifled by its waste heat. So life will disappear.

This dismal view of the future was in startling contrast to the ebullient growth of life that we see around us. Thanks to the discoveries of astronomers in the twentieth century, we now know that the heat death is a myth. The heat death can never happen, and there is no paradox. The best popular account of the disappearance of the paradox is a chapter, “How Order Was Born of Chaos,” in the book Creation of the Universe, by Fang Lizhi and his wife Li Shuxian. Fang Lizhi is doubly famous as a leading Chinese astronomer and a leading political dissident. He is now pursuing his double career at the University of Arizona.

The belief in a heat death was based on an idea that I call the cooking rule. The cooking rule says that a piece of steak gets warmer when we put it on a hot grill. More generally, the rule says that any object gets warmer when it gains energy, and gets cooler when it loses energy. Humans have been cooking steaks for thousands of years, and nobody ever saw a steak get colder while cooking on a fire. The cooking rule is true for objects small enough for us to handle. If the cooking rule is always true, then Lord Kelvin’s argument for the heat death is correct.

We now know that the cooking rule is not true for objects of astronomical size, for which gravitation is the dominant form of energy. The sun is a familiar example. As the sun loses energy by radiation, it becomes hotter and not cooler. Since the sun is made of compressible gas squeezed by its own gravitation, loss of energy causes it to become smaller and denser, and the compression causes it to become hotter. For almost all astronomical objects, gravitation dominates, and they have the same unexpected behavior. Gravitation reverses the usual relation between energy and temperature. In the domain of astronomy, when heat flows from hotter to cooler objects, the hot objects get hotter and the cool objects get cooler. As a result, temperature differences in the astronomical universe tend to increase rather than decrease as time goes on. There is no final state of uniform temperature, and there is no heat death. Gravitation gives us a universe hospitable to life. Information and order can continue to grow for billions of years in the future, as they have evidently grown in the past.
I thoroughly enjoyed Freeman Dyson's review. Now I can look forward to reading James Gleick's book. I've got myself signed up for the first copy at the local library!

This review points at an article by James Gleick that was published too late to be included in his book. It was published as the article "The Information Palace" in the NY Review of Books:
The word “information” has grown urgent and problematic—a signpost seen everywhere, freighted with new meaning and import. We hardly need the lexicographers of the Oxford English Dictionary to tell us that, but after all, this is what they live for. It is a word, they tell us, “exhibiting significant linguistic productivity,” a word that “both reflects and embodies major cultural and technological change,” therefore a word crying out for their attention. In their latest quarterly revision, December 2010, just posted, the entry for “information” is utterly overhauled. (The OED, in case you hadn’t noticed, has evolved into an enterprise of cyberspace, rather than a mere book.)

The renovation has turned a cottage into a palace. Information, n., now runs 9,400 words, the length of a novella. It is a sort of masterpiece—an adventure in cultural history. A century ago “information” did not have much resonance. It was a nothing word. “An item of training; an instruction.” Now (as people have been saying for fifty years) we are in the Information Age. Which, by the way, the OED defines for us in its dry-as-chili-powder prose: “the era in which the retrieval, management, and transmission of information, esp. by using computer technology, is a principal (commercial) activity.”


Originally—and by originally I mean in the fourteenth century, when the written record begins, as far as the OED can tell—the word had a sinister flavor. It budged its way into the old gruff Anglo-Saxon as part of the Norman invasion. It meant something like “accusation” or “incrimination.” The earliest citation comes from the Rolls of Parliament for 1386: “Thanne were such proclamacions made‥bi suggestion & informacion of suche that wolde nought her falsnesse had be knowen to owre lige Lorde.” For centuries thereafter, informations were filed, or recorded, or laid, against people.

From then to now the word takes a twisty path, and the OED‘s lexicographers hold our hand around every corner. Information can be “a teaching; an instruction.” It can be “divine influence or direction; inspiration, esp. through the Holy spirit.” It can be “that of which one is apprised or told; intelligence, news.”
And this bit of sleuthing in the OED gives Gleick:
By the way, how do we know people have been talking about the Information Age for fifty years? The OED tells us. The first recorded usage is attributed to “R. S. Leghorn in H. B. Maynard Top Managem. Handbk. xlvii. 1024,” 1960. He turns out to have been Richard Leghorn, founder of Itek Corporation, which made aerospace spy cameras, and later Chief of Intelligence and Reconnaissance Systems Development at the Pentagon. In a single sentence Leghorn invented the phrase and predicted it would not catch on:
Present and anticipated spectacular informational achievements will usher in public recognition of the “information age,” probably under a more symbolic title.
No better title has come along. Along with information age, the OED now recognizes information storage, information transfer, information processing, information retrieval, information architecture, information superhighway, plus (the bad news) information explosion, gap, warfare, overload, and fatigue.

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