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Authors: Freeman Dyson

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After I came to America, I became a friend of Velikovsky, who was my neighbor in Princeton. Velikovsky was a Russian Jew with an
intense interest in Jewish legends and ancient history. He was born into a scholarly family in 1895 and obtained a medical degree at Moscow University in 1921. During the chaos of the Bolshevik Revolution he wrote a long Russian poem with the title “Thirty Days and Nights of Diego Pirez on the Sant’Angelo Bridge.” It was published in Paris in 1935. Diego Pirez was a sixteenth-century Portuguese Jewish mystic who came to Rome and sat on the bridge near the Vatican, surrounded by beggars and thieves to whom he told his apocalyptic visions. He was condemned to death by the Inquisition, pardoned by the pope, and later burned as a heretic by the emperor Charles V.

Velikovsky escaped from Russia and settled in Palestine with his wife and daughters. He described to me the joys of practicing medicine on the slopes of Mount Carmel above Haifa, where he rode on a donkey to visit his patients in their homes. He founded and edited a journal,
Scripta Universitatis atque Bibliothecae Hierosolymitanarum
, which was the official journal of the Hebrew University before the university was established. His work for the
Scripta
was important for the founding of the Hebrew University. But he had no wish to join the university himself. To fulfill his dreams he needed complete independence. In 1939, after sixteen years in Palestine, he moved to America, where he had no license to practice medicine. To survive in America, he needed to translate his dreams into books.

Eleven years later, Macmillan published
Worlds in Collision
, and it became a best seller. Like Diego Pirez, Velikovsky told his dreams to the public in language they could understand. His dreams were mythological stories of catastrophic events, gleaned from many cultures, especially from ancient Egypt and Israel. These catastrophes were interwoven with a weird history of planetary collisions. The planets Venus and Mars were supposed to have moved out of their regular orbits and collided with the Earth a few thousand years ago.
Electromagnetic forces were invoked to counteract the normal effects of gravity. The human and cosmic events were tied together in a flowing narrative. Velikovsky wrote like an Old Testament prophet, calling down fire and brimstone from heaven, in a style familiar to Americans raised on the King James Bible. More best sellers followed:
Ages in Chaos
in 1952,
Earth in Upheaval
in 1955,
Oedipus and Akhnaton
in 1960. Velikovsky became famous as a writer and as a public speaker.

In 1977 Velikovsky asked me to write a blurb advertising his new book,
Peoples of the Sea.
I wrote a statement addressed to him personally:

First, as a scientist, I disagree profoundly with many of the statements in your books. Second, as your friend, I disagree even more profoundly with those scientists who have tried to silence your voice. To me, you are no reincarnation of Copernicus or Galileo. You are a prophet in the tradition of William Blake, a man reviled and ridiculed by his contemporaries but now recognized as one of the greatest of English poets. A hundred and seventy years ago, Blake wrote: “The Enquiry in England is not whether a Man has Talents and Genius, but whether he is Passive and Polite and a Virtuous Ass and obedient to Noblemen’s Opinions in Art and Science. If he is, he is a Good Man. If not, he must be starved.” So you stand in good company. Blake, a buffoon to his enemies and an embarrassment to his friends, saw Earth and Heaven more clearly than any of them. Your poetic visions are as large as his and as deeply rooted in human experience. I am proud to be numbered among your friends.

I added the emphatic instruction, “This statement to be printed in its entirety or not at all.” A quick response came from Velikovsky. He
said, “How would you like it if I said you were the reincarnation of Jules Verne?” He wanted to be honored as a scientist, not as a poet. My statement was not printed, and
Peoples of the Sea
became a best seller without my help. We remained friends, and in that same year he gave me a copy of his Diego Pirez poem, which I treasure as the truest expression of his spirit. I hope it will one day be adequately translated into English.

Why do I value so highly the memory of Eddington and Velikovsky, and why does Wertheim treasure the memory of Thomson and Carter? We honor them because science is only a small part of human capability. We gain knowledge of our place in the universe not only from science but also from history, art, and literature. Science is a creative interaction of observation with imagination. “Physics at the fringe” is what happens when imagination loses touch with observation. Imagination by itself can still enlarge our vision when observation fails. The mythologies of Carter and Velikovsky fail to be science, but they are works of art and high imagining. As Blake told us long ago, “You never know what is enough unless you know what is more than enough.”

Wertheim ends her book with a description of two conferences that she attended. The first was in 2003 at the Kavli Institute for Theoretical Physics at Santa Barbara. The second was in 2010 at California State University in Long Beach. Both conferences were supposed to be about physics. The subject of the Santa Barbara conference was “string cosmology.” It was a gathering of the leading professional experts in the most fashionable part of theoretical physics, with David Gross, who won a Nobel Prize in 2004, presiding. Each expert in turn described a personal vision of the cosmos, delineating either a single universe or a multiplicity of universes. The various visions were incompatible with one another, and no observational evidence could prove any of them right or wrong.

The Long Beach conference was organized by the NPA, the amateurs on the fringe. Their meeting resembled a professional conference, with PowerPoint presentations followed by vigorous question-and-answer sessions. Carter was there and presented his vision of the universe among 120 others. Wertheim was probably the only person who attended both conferences. She is one of very few people who are at home in both worlds. She is a professional science writer with a degree in physics, and she has made friends with many insiders as well as outsiders. She asks at the end the central question raised by her book: Why should we pay more attention to one set of self-proclaimed experts than to the other?

So far as science in general is concerned, the answer to Wertheim’s question is clear. There is good reason to pay more attention to scientific experts than to amateurs, so long as science is based on experiments. Only trained experts can do experiments with the care and precision that experiments demand. Expert experimenters are not infallible, but they are less fallible than amateurs. Experiments give orthodox beliefs a solid basis. An experimental basis exists for the established disciplines of physics and chemistry and biology. However, some parts of physics are less secure than others, because the experts in physics are divided into experimenters and theorists.

Over most of the territory of physics, theorists and experimenters are engaged in a common enterprise, and theories are tested rigorously by experiment. The theorists listen to the voice of nature speaking through experimental tools. This was true for the great theorists of the early twentieth century, Einstein and Heisenberg and Schrödinger, whose revolutionary theories of relativity and quantum mechanics were tested by precise experiments and found to fit the facts of nature. The new mathematical abstractions fit the facts, while the old mechanical models did not.

String cosmology is different. String cosmology is a part of
theoretical physics that has become detached from experiments. String cosmologists are free to imagine universes and multiverses, guided by intuition and aesthetic judgment alone. Their creations must be logically consistent and mathematically elegant, but they are otherwise unconstrained. That is why Wertheim found the official string cosmology conference disconcertingly similar to the unofficial NPA conference. The insiders and the outsiders seem to be following the same rules. Both groups are telling stories of imagined worlds, and neither has an assured way of deciding who is right. If the title
Physics on the Fringe
fits the natural philosophers, the same title also fits the string cosmologists.

The fringe of physics is not a sharp boundary with truth on one side and fantasy on the other. All of science is uncertain and subject to revision. The glory of science is to imagine more than we can prove. The fringe is the unexplored territory where truth and fantasy are not yet disentangled. Hermann Weyl, who was one of the main architects of the relativity and quantum revolutions, said to me once, “I always try to combine the true with the beautiful, but when I have to choose one or the other, I usually choose the beautiful.” Following Weyl’s good example, our string cosmologists are making the same choice.

Note added in 2014: Velikovsky’s elder daughter, Shulamit Kogan, settled with her husband in Israel; the younger daughter, Ruth Sharon, settled in Princeton. Both daughters were fiercely loyal to their father. Ruth took care of the Velikovsky archive until 2005, when she presented it to the Princeton University Library. She published a biography
, Aba, the Glory and the Torment: The Life of Dr. Immanuel Velikovsky
(Paradigma, 2010).

*
Margaret Wertheim,
Physics on the Fringe: Smoke Rings, Circlons, and Alternative Theories of Everything
(Walker, 2011).

14
HOW WE KNOW

THE FIRST CHAPTER
of James Gleick’s
The Information
has the title “Drums That Talk.”
*
It explains the concept of information by looking at a simple example. The example is a drum language used in a part of the Democratic Republic of Congo where the human language is Kele. European explorers had been aware for a long time that the irregular rhythms of African drums were carrying mysterious messages through the jungle. Explorers would arrive at villages where no European had been before and find that the village elders were already prepared to meet them.

Sadly, the drum language was only understood and recorded by a single European before it started to disappear. The European was John Carrington, an English missionary who spent his life in Africa and became fluent in both Kele and drum language. He arrived in Africa in 1938 and published his findings in 1949 in a book,
The Talking Drums of Africa.

Before the arrival of the Europeans with their roads and radios, the Kele-speaking Africans had used the drum language for rapid communication from village to village in
the rain forest. Every village had an expert drummer and every villager could understand what the drums were saying. By the time Carrington wrote his book, the use of drum language was already fading and schoolchildren were no longer learning it. In the sixty years since then, telephones made drum language obsolete and completed the process of extinction.

Carrington understood how the structure of the Kele language made drum language possible. Kele is a tonal language with two sharply distinct tones. Each syllable is either low or high. The drum language is spoken by a pair of drums with the same two tones. Each Kele word is spoken by the drums as a sequence of low and high beats. In passing from human Kele to drum language, all the information contained in vowels and consonants is lost. In a European language, the consonants and vowels contain all the information, and if this information were dropped there would be nothing left. But in a tonal language like Kele, some information is carried in the tones and survives the transition from human speaker to drums. The fraction of information that survives in a drum word is small, and the words spoken by the drums are correspondingly ambiguous. A single sequence of tones may have hundreds of meanings depending on the missing vowels and consonants. The drum language must resolve the ambiguity of the individual words by adding more words. When enough redundant words are added, the meaning of the message becomes unique.

In 1954 a visitor from the United States came to Carrington’s mission school. Carrington was taking a walk in the forest and his wife wished to call him home for lunch. She sent him a message in drum language and explained it to the visitor. To be intelligible to Carrington, the message needed to be expressed with redundant and repeated phrases: “White man spirit in forest come come to house of shingles high up above of white man spirit in forest. Woman with
yam awaits. Come come.” Carrington heard the message and came home. On the average, about eight words of drum language were needed to transmit one word of human language unambiguously. Western mathematicians would say that about one eighth of the information in the human Kele language belongs to the tones that are transmitted by the drum language. The redundancy of the drum language phrases compensates for the loss of the information in vowels and consonants. The African drummers knew nothing of Western mathematics, but they found the right level of redundancy for their drum language by trial and error. Carrington’s wife had learned the language from the drummers and knew how to use it.

The story of the drum language illustrates the central dogma of information theory. The central dogma says, “Meaning is irrelevant.” Information is independent of the meaning that it expresses and of the language used to express it. Information is an abstract concept, which can be embodied equally well in human speech or in writing or in drumbeats. All that is needed to transfer information from one language to another is a coding system. A coding system may be simple or complicated. If the code is simple, as it is for the drum language with its two tones, a given amount of information requires a longer message. If the code is complicated, as it is for spoken language, the same amount of information can be conveyed in a shorter message.

Another example illustrating the central dogma is the French optical telegraph. Until 1793, the fifth year of the French Revolution, the African drummers were ahead of Europeans in their ability to transmit information rapidly over long distances. In 1793, Claude Chappe, a patriotic citizen of France, wishing to strengthen the defense of the revolutionary government against domestic and foreign enemies, invented a device that he called the telegraph. The telegraph was an optical communication system with stations consisting of
large movable pointers mounted on the tops of sixty-foot towers. Each station was manned by an operator who could read a message transmitted by a neighboring station and transmit the same message to the next station in the transmission line.

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