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Freeman Dyson

From Wikipedia, the free encyclopedia

Freeman Dyson
Freeman Dyson
Freeman Dyson
Born December 15, 1923
Crowthorne, Berkshire, England
Residence USA
Nationality British (pre-1957)
American (post-1957)
Field Physicist
Institution Royal Air Force
Institute for Advanced Study
Cornell University
Alma mater University of Cambridge
Academic advisor None
Known for Dyson sphere
Dyson operator
Notable prizes Templeton Prize (2000)
He is notably the son of George Dyson (composer), and father of Esther Dyson and George Dyson (science historian).

Freeman John Dyson FRS (born December 15, 1923) is a British-born American physicist and mathematician, famous for his work in quantum mechanics, solid-state physics, nuclear weapons design and policy, and for his serious theorizing in futurism and science fiction concepts, including the search for extraterrestrial intelligence. He is a lifelong opponent of nationalism, and proponent of nuclear disarmament and international cooperation. Dyson is a member of the Board of Sponsors of The Bulletin of the Atomic Scientists.[1]

Contents

[edit] Biography

[edit] Personal

He has six children. One daughter is Esther Dyson, the noted digital technology consultant. His son is the historian of technology George Dyson, one of whose books is Project Orion: The Atomic Spaceship 1957-1965. His wife, Imme Dyson, is an accomplished masters runner. Dyson's father was the renowned English composer George Dyson. Despite sharing a last name, he is not related to early 20th-century astronomer Frank Watson Dyson. However, as a small boy Freeman Dyson was aware of Frank Watson Dyson; Freeman credits the popularity of someone with the same last name with inadvertently helping to spark his interest in science. Dyson received a Sc.D. from Bates College in 1990. A boy in Tonganoxie, Kansas, USA, was named Dyson Felty in honor of Dyson (February 12 2000); when informed of this, he unofficially adopted Dyson Felty as his godson.[citation needed]

On Esther Dyson, his daughter:

The main advantage she had was being neglected. We had two other children [then], one older and one younger, who were real problems. She wasn't a problem, and so she didn't get much attention. She always knew what she wanted, and she was very quiet and easygoing.[2]

[edit] Career

Dyson worked as an analyst for RAF Bomber Command during World War II.[3] After the war, he obtained a BA degree in mathematics from Cambridge University (1945) and was a Fellow at Trinity College, Cambridge from 1946 to 1949. In 1947 he moved to the US, on a fellowship at Cornell University and then joined the faculty there as a physics professor in 1951 without a PhD. He was elected a FRS in 1952[4] In 1953, he took up a post at the Institute for Advanced Study in Princeton, NJ. In 1957, he became a naturalized citizen of the United States.

In the years following the war, Dyson was responsible for demonstrating the equivalence of the two formulations of quantum electrodynamics which existed at the time—Richard Feynman's diagrammatic path integral formulation and the variational methods developed by Julian Schwinger and Sin-Itiro Tomonaga (Dyson operator).

From 1957 to 1961 he worked on the Orion Project, which proposed the possibility of space-flight using nuclear pulse propulsion. A prototype was demonstrated using conventional explosives, but a treaty banning the use of nuclear weapons in space caused the project to be abandoned.

In 1958 he led the design team for the TRIGA, a small, inherently safe nuclear reactor used throughout the world in hospitals and universities for the production of isotopes.

In 1977, Dyson supervised Princeton undergraduate John Aristotle Phillips in a term paper that outlined a credible design for a nuclear weapon. This earned Phillips the nickname The A-Bomb Kid.

Dyson has published a number of collections of speculations and observations about technology, science, and the future.

Dyson was awarded the Lorentz Medal in 1966 and Max Planck medal in 1969. In the 1984–85 academic year he gave the Gifford lectures at Aberdeen, which resulted in the book Infinite In All Directions.

In 1998, Dyson joined the board of the Solar Electric Light Fund. In 2000, Dyson was awarded the Templeton Prize for Progress in Religion.

In 1989, Dyson taught at Duke University as a Fritz London Memorial Lecturer.

As of 2003, Dyson is the president of the Space Studies Institute, the space research organization founded by Gerard K. O'Neill.

In 2003, Dyson was awarded the Telluride Tech Festival Award of Technology in Telluride, Colorado.

Dyson was a long time member of the JASON defense advisory group.

[edit] Concepts

[edit] Biotechnology and genetic engineering

In The Sun, the Genome, and the Internet, Dyson proposes engineering "trees that convert sunlight to liquid fuel and deliver the fuel directly …to underground pipelines." A neat solution to declining oil reserves, if it works. Dyson cheerfully admits his record as a prophet is mixed, but "it is better to be wrong than to be vague."

To answer the world's material needs, technology has to be not only beautiful but also cheap.[5]

[edit] Dyson sphere

Main article: Dyson sphere

One should expect that, within a few thousand years of its entering the stage of industrial development, any intelligent species should be found occupying an artificial biosphere which completely surrounds its parent star.[6]

In 1960 Dyson wrote a short paper for the journal Science, entitled "Search for Artificial Stellar Sources of Infrared Radiation".[7] In it, he theorized that a technologically advanced society might completely surround its native star in order to maximize the capture of the star's available energy. Eventually, the civilization would completely enclose the star, intercepting electromagnetic radiation with wavelengths from visible light downwards and radiating waste heat outwards as infrared radiation. Therefore, one method of searching for extraterrestrial civilizations would be to look for large objects radiating in the infrared range of the electromagnetic spectrum.

Dyson conceived that such structures would be clouds of asteroid-sized space habitats, though science fiction writers have preferred a solid structure: either way, such an artifact is often referred to as a Dyson sphere, although Dyson himself used the term "shell". Dyson says that he used the word "artificial biosphere" in the article meaning a habitat, not a shape.[8]

[edit] Dyson tree

Main article: Dyson tree

Dyson has also proposed the creation of a Dyson tree, a genetically-engineered plant capable of growing on a comet. He suggested that comets could be engineered to contain hollow spaces filled with a breathable atmosphere, thus providing self-sustaining habitats for humanity in the outer solar system.

Plants could grow greenhouses…just as turtles grow shells and polar bears grow fur and polyps build coral reefs in tropical seas. These plants could keep warm by the light from a distant Sun and conserve the oxygen that they produce by photosynthesis. The greenhouse would consist of a thick skin providing thermal insulation, with small transparent windows to admit sunlight. Outside the skin would be an array of simple lenses, focusing sunlight through the windows into the interior… Groups of greenhouses could grow together to form extended habitats for other species of plants and animals.[9]

—including humans, of course.

[edit] Space colonies

I've done some historical research on the costs of the Mayflower's voyage, and on the Mormons' emigration to Utah, and I think it's possible to go into space on a much smaller scale. A cost on the order of $40,000 per person [1978 dollars] would be the target to shoot for; in terms of real wages, that would make it comparable to the colonization of America. Unless it's brought down to that level it's not really interesting to me, because otherwise it would be a luxury that only governments could afford.[10]

Freeman Dyson has been interested in space travel since he was a child, reading such science fiction classics as Olaf Stapledon's Star Maker. As a young man, he worked for General Atomics on the nuclear-powered Orion spacecraft. He hoped Project Orion would put men on Mars by 1965, Saturn by 1970. He's been unhappy for a quarter-century on how the government conducts space travel:

The problem is, of course, that they can't afford to fail. The rules of the game are that you don't take a chance, because if you fail, then probably your whole program gets wiped out.[11]

He still hopes for cheap space travel, but is resigned to waiting for private entrepreneurs to develop something new—and cheap.

No law of physics or biology forbids cheap travel and settlement all over the solar system and beyond. But it is impossible to predict how long this will take. Predictions of the dates of future achievements are notoriously fallible. My guess is that the era of cheap unmanned missions will be the next fifty years, and the era of cheap manned missions will start sometime late in the twenty-first century.

Any affordable program of manned exploration must be centered in biology, and its time frame tied to the time frame of biotechnology; a hundred years, roughly the time it will take us to learn to grow warm-blooded plants, is probably reasonable.[12]

[edit] Space exploration

A direct search for life in Europa's ocean would today be prohibitively expensive. Impacts on Europa give us an easier way to look for evidence of life there. Every time a major impact occurs on Europa, a vast quantity of water is splashed from the ocean into the space around Jupiter. Some of the water evaporates, and some condenses into snow. Creatures living in the water far enough from the impact have a chance of being splashed intact into space and quickly freeze-dried. Therefore, an easy way to look for evidence of life in Europa's ocean is to look for freeze-dried fish in the ring of space debris orbiting Jupiter.[13]

[edit] Dyson's transform

Dyson also has some credits in Elementary number theory. His concept "Dyson's transform" led to one of the most important lemmas of Olivier Ramaré's theorem that every even integer is a sum of at most six primes.

[edit] Views

[edit] Criticism of global warming studies

Dyson has questioned the predictive value of current computational models of climate change, urging instead more extensive use of local observations. He considers this view to be "heretical", along with his views on the PhD system.

The good news is that we are at last putting serious effort and money into local observations. Local observations are laborious and slow, but they are essential if we are ever to have an accurate picture of climate. The bad news is that the climate models on which so much effort is expended are unreliable because they still use fudge-factors rather than physics to represent important things like evaporation and convection, clouds and rainfall. Besides the general prevalence of fudge-factors, the latest and biggest climate models have other defects that make them unreliable. With one exception, they do not predict the existence of El Niño. Since El Niño is a major feature of the observed climate, any model that fails to predict it is clearly deficient. The bad news does not mean that climate models are worthless. They are, as Manabe said thirty years ago, essential tools for understanding climate. They are not yet adequate tools for predicting climate.[14]

While he acknowledges climate change may be in part due to anthropogenic causes, such as the burning of fossil fuels, he regards the term "global warming" as a misnomer:

As a result of the burning of coal and oil, the driving of cars, and other human activities, the carbon dioxide in the atmosphere is increasing at a rate of about half a percent per year. … The physical effects of carbon dioxide are seen in changes of rainfall, cloudiness, wind strength, and temperature, which are customarily lumped together in the misleading phrase "global warming." This phrase is misleading because the warming caused by the greenhouse effect of increased carbon dioxide is not evenly distributed. In humid air, the effect of carbon dioxide on the transport of heat by radiation is less important, because it is outweighed by the much larger greenhouse effect of water vapor. The effect of carbon dioxide is more important where the air is dry, and air is usually dry only where it is cold. The warming mainly occurs where air is cold and dry, mainly in the arctic rather than in the tropics, mainly in winter rather than in summer, and mainly at night rather than in daytime. The warming is real, but it is mostly making cold places warmer rather than making hot places hotter. To represent this local warming by a global average is misleading, because the global average is only a fraction of a degree while the local warming at high latitudes is much larger.[15]

Regarding political efforts to reduce the causes of climate change, Dyson argues that other global problems should take priority.

I'm not saying the warming doesn't cause problems, obviously it does. Obviously we should be trying to understand it. I'm saying that the problems are being grossly exaggerated. They take away money and attention from other problems that are much more urgent and important. Poverty, infectious diseases, public education and public health. Not to mention the preservation of living creatures on land and in the oceans.[16]

[edit] Bureaucracy

At the British Bomber Command, Dyson and colleagues proposed ripping out two gun turrets from the RAF Lancaster bombers, to cut the catastrophic losses to German fighters in the Battle of Berlin. A Lancaster without turrets could fly 50 mph faster and be much more maneuverable.

All our advice to the commander in chief [went] through the chief of our section, who was a career civil servant. His guiding principle was to tell the commander in chief things that the commander in chief liked to hear… To push the idea of ripping out gun turrets, against the official mythology of the gallant gunner defending his crewmates…was not the kind of suggestion the commander in chief liked to hear.[17]

[edit] Warfare and weapons

On hearing the news of the bombing of Hiroshima:

I agreed emphatically with Henry Stimson. Once we had got ourselves into the business of bombing cities, we might as well do the job competently and get it over with.

I felt better that morning than I had felt for years… Those fellows who had built the atomic bombs obviously knew their stuff… Later, much later, I would remember [the downside].[18]

[edit] The role of failure

You can't possibly get a good technology going without an enormous number of failures. It's a universal rule. If you look at bicycles, there were thousands of weird models built and tried before they found the one that really worked. You could never design a bicycle theoretically. Even now, after we've been building them for 100 years, it's very difficult to understand just why a bicycle works - it's even difficult to formulate it as a mathematical problem. But just by trial and error, we found out how to do it, and the error was essential.[19]

[edit] Science and Religion

Dyson is a strong opponent of reductionism. He is a non-dogmatic Christian, happy to attend various churches and indifferent to much theology.[20]

Science and religion are two windows that people look through, trying to understand the big universe outside, trying to understand why we are here. The two windows give different views, but they look out at the same universe. Both views are one-sided, neither is complete. Both leave out essential features of the real world. And both are worthy of respect.

Trouble arises when either science or religion claims universal jurisdiction, when either religious dogma or scientific dogma claims to be infallible. Religious creationists and scientific materialists are equally dogmatic and insensitive. By their arrogance they bring both science and religion into disrepute. The media exaggerate their numbers and importance. The media rarely mention the fact that the great majority of religious people belong to moderate denominations that treat science with respect, or the fact that the great majority of scientists treat religion with respect so long as religion does not claim jurisdiction over scientific questions.[20]

Dyson disagrees with the famous remark by his fellow-physicist Steven Weinberg that "Good people will do good things, and bad people will do bad things. But for good people to do bad things—that takes religion."[21]

Weinberg's statement is true as far as it goes, but it is not the whole truth. To make it the whole truth, we must add an additional clause: "And for bad people to do good things—that takes religion." The main point of Christianity is that it is a religion for sinners. Jesus made that very clear. When the Pharisees asked his disciples, "Why eateth your Master with publicans and sinners?" he said, "I come to call not the righteous but sinners to repentance." Only a small fraction of sinners repent and do good things, but only a small fraction of good people are led by their religion to do bad things.[21]

[edit] Popular Culture

The fictional character Gordon Freeman in the Half-Life franchise was named after Dyson.

As noted above, the Dyson sphere is a favorite of science-fiction authors. See Dyson spheres in fiction

[edit] See also

[edit] References

  1. ^ Bulletin of the Atomic Scientists
  2. ^ Interview by Stewart Brand, February 1998
  3. ^ "A Failure of Intelligence", Essay in Technology Review (Nov–Dec 2006)
  4. ^ Royal Society directory entry
  5. ^ Dyson, FJ, "The Greening of the Galaxy" in Disturbing the Universe, 1979
  6. ^ Interview by Monte Davis, October 1978
  7. ^ Dyson, Freeman J. (3 June 1960). "Search for Artificial Stellar Sources of Infrared Radiation". Science 131 (3414): 1667 - 1668. DOI:10.1126/science.131.3414.1667. 
  8. ^ 20 minutes into a video
  9. ^ Dyson, FJ, "Warm-blooded plants and freeze-dried fish: the future of space exploration." The Atlantic Monthly, Nov 1997 Subscribers only
  10. ^ Interview by Monte Davis, October 1978
  11. ^ Interview by Monte Davis, October 1978
  12. ^ Dyson, FJ, "Warm-blooded plants and freeze-dried fish: the future of space exploration.", op. cit.
  13. ^ Dyson, FJ, "Warm-blooded plants and freeze-dried fish: the future of space exploration", The Atlantic Monthly, Nov. 1997
  14. ^ American Physical Society newsletter, May 1999
  15. ^ Dyson in a review in The New York Review of Books, 15 March 2003
  16. ^ University of Michigan 2005Winter Commencement Address
  17. ^ FJ Dyson, "The Children's Crusade" in Disturbing the Universe, 1979
  18. ^ FJ Dyson, "The Blood of a Poet" in Disturbing the Universe, 1979
  19. ^ Interview by Stewart Brand, February 1998
  20. ^ a b Templeton Prize Lecture
  21. ^ a b NYRB June 22, 2006

[edit] Books

[edit] By Dyson

  • Disturbing the Universe, 1979
  • Weapons and Hope, 1984
  • Infinite in all Directions, 1988
  • Origins of Life, 1986
  • From Eros to Gaia, 1992
  • Selected Papers of Freeman Dyson, 1996
  • Imagined Worlds, 1997
  • The Sun, The Genome and The Internet, 1999
  • The Scientist as Rebel, 2006

[edit] About Dyson

  • Brower, Kenneth, 1978. The Starship and the Canoe, Holt Rinehart and Winston.
  • Schweber, Sylvan S., 1994. QED and the men who made it : Dyson, Feynman, Schwinger, and Tomonaga. Princeton Univ. Press.

[edit] External links

Wikiquote has a collection of quotations related to:


Persondata
NAME Dyson, Freeman John
ALTERNATIVE NAMES
SHORT DESCRIPTION Physicist and mathematician
DATE OF BIRTH December 15, 1923
PLACE OF BIRTH England
DATE OF DEATH
PLACE OF DEATH
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