Biography: Freeman Dyson
Theoretical Physicist and Author

Freeman Dyson was born in Crowthorne, in the county of Berkshire, England. His father, George Dyson, was a composer and educator. His mother was trained as an attorney and worked with her father's law practice prior to her marriage. Young Freeman Dyson showed precocious ability in mathematics, and took a great interest in science and philosophy from an early age. He read science fiction and enjoyed speculating about space travel and life in outer space. He was also preoccupied with philosophical questions of war, peace, and social justice, issues that would continue to concern him in his career as a scientist.

Young Freeman attended Winchester College, the prestigious boarding school where his father taught music. The elder Dyson would leave Winchester to direct the Royal College of Music, and received a knighthood. Freeman Dyson graduated from Winchester and entered Cambridge University. His studies were interrupted by World War II; he served as a civilian statistician in the operational research section of the Royal Air Force Bomber Command. At war's end, he returned to Cambridge, where he completed a degree in mathematics and was named a Fellow of Trinity College. He was offered a Harkness Fellowship to study in the United States, and arrived at Cornell University in Ithaca, New York in 1947.

Cornell in the late 1940s was the center of advanced research in physics, with many veterans of the Manhattan project on faculty. Dyson fell in with the iconoclastic young physicist Richard Feynman. Only five years older than Dyson himself, Feynman had already created a controversy in the rarefied world of quantum electrodynamics (QED). Feynman created a pictorial system for representing the behavior of subatomic particles, now known as the Feynman Diagrams. Two other physicists, Julian Schwinger and Sin-Itiro Tomonaga, had developed a different model for representing these phenomena, the so-called "operator method," which had already won acceptance. Established physicists, including the revered J. Robert Oppenheimer, rejected the Feynman Diagrams as incompatible with the operator method. Dyson believed in the Feynman Diagrams, and was able to prove mathematically that, properly understood, the diagrams and the operator method were entirely compatible. His 1949 paper and subsequent lectures on the subject led many physicists, including Oppenheimer, to recognize the validity of Feynman's theory.

Dyson applied the Feynman Diagrams to scattering theory, a branch of physics that describes the scattering of waves and particles, and explains the behavior of everything from billiard balls to rainbows. He discovered an elaborate mathematical sequence, now known as the Dyson Series, that filled in major gaps in scattering theory, further extending the reach of QED.

In 1951, Dyson was appointed to a physics professorship at Cornell, even though he had not completed a doctorate and his undergraduate degree was in mathematics. The same year, he was named a Fellow of the Royal Society. Dyson had only taught at Cornell for a few years when, in 1953, J. Robert Oppenheimer offered him a lifetime appointment at the Institute for Advanced Study at Princeton. The Institute, where Albert Einstein had spent his last years, afforded Dyson the freedom to carry on research in any area that interested him. Oppenheimer wanted to reward Dyson for, as he put it, "proving me wrong." Dyson remained at the Institute for 43 years.

In 1957, Freeman Dyson became a United States citizen. That same year, marked a return to one of his favorite interests: space travel; he joined the Orion Project, which explored the application of nuclear technology to space travel. Dyson also led the design team that produced TRIGA, the safe, compact nuclear reactor used in hospital and laboratories the world over to produce isotopes for research and therapy. The peaceful application of nuclear energy was a major concern for Dyson throughout his career, especially in the 1950s and '60s. Concern over the environmental and public health consequences of open-air nuclear weapons testing led many scientists, including Dyson, to call for an international treaty, banning above-ground testing.

In 1963, President John F. Kennedy signed the first Limited Nuclear Test Ban Treaty. A prototype Orion space vehicle was tested using conventional explosives, but in 1964, in the face of growingconcern over the dangers of releasing nuclear energy into the atmosphere, the Orion Project was discontinued. Dyson was consulted on nuclear weapons and other technology issues by successive administrations in Washington. His counsel was particularly influential in dissuading the military from considering the use of tactical nuclear weapons in the Vietnam War.

One of Dyson's major achievements in physics came in 1966 when, along with his colleague Andrew Lenard, he demonstrated that the stability of bulk matter is due to the exclusion principle, applied to electrons and protons, not to electromagnetic repulsion, as had been supposed. This fortified physicists' understanding of the "normal force," one of the pillars of classical physics.

Dyson made substantial contributions to the field of condensed matter physics while working on a dizzying variety of mathematical problems in the fields of topology, number theory and random matrices. One of these occurred in 1973, when he detected the relationship of a new conjecture in number theory to a more familiar concept in physics, suggesting a correlation between the distribution of prime numbers and energy levels in the nuclei of heavy elements, such as uranium.

His ability to find the links between applied sciences and mathematics has made Dyson an invaluable collaborator to specialists in many areas. In 1979 he worked with the Institute for Energy Analysis on a climate study project. These were among the first studies to bring together meteorologists, physicists, mathematicians and biologists to study climate. These studies led to widespread concern that human activities, notably deforestation and burning of fossil fuels, were contributing to pronounced changes in the global climate. Dyson accepted the essence of these findings, but his nuanced position on the issue would later cause friction with some of his colleagues.

In 1979, he published an autobiography, Disturbing the Universe, that not only recounted his youth, his experiences in the Second World War, and his friendships with the great minds of our age, but presented a basic outline of his scientific thought to the general reader. In this and subsequent books, Dyson showed a rare ability to convey highly complex and obscure concepts in simple, comprehensible terms. He had launched himself on what he has called "a second career," as an author.

In 1984 he published a book on "nuclear arms and the human predicament. " Weapons and Hope became a bestseller and received the National Book Award in the United States. That same year, he was selected to give the Gifford Lectures in Scotland. One of the highest honors in Scottish academia, the lectures typically address theological or philosophical concerns. Over the years, Dyson had set himself apart from others in the scientific community with his openness to religious and metaphysical speculation. He has described himself as a "practicing Christian," although he makes no specific assertions on Christian doctrine. Dyson's lectures, given at the University of Aberdeen, were published in 1988 as Infinite in All Directions. In the book and lectures, Dyson proposed a "mental component of the universe," and continued, "If we believe in this mental component and call it God, then we can say that we are small pieces of God's mental apparatus."

In speculative writings since the 1960s, Dyson has proposed the possibility of an interplanetary civilization enclosing its sun to capture its useful energy and expel its waste heat as infrared radiation. This model of an artificial biosphere has been much discussed by space travel theorists, who call it a Dyson Sphere. They use the phrase Dyson Tree to refer to another key concept of Dyson's thinking on space, the genetic engineering of plants that can grow on other planetary bodies, even asteroids or comets, to create a self-sustaining oxygen-rich environment that will support human life. He discusses his thoughts on the colonization of space in a 1992 book From Eros to Gaia.

Dyson retired from the Institute for Advanced Study in 1994, although he retains the title Professor Emeritus, and continues to reside in Princeton. He has devoted much of his energy to solar power and the study of space travel. Since retiring from the Institute, he has served on the boards of the Solar Electric Light Fund and the Space Studies Institute, and is a longtime member of the JASON defense advisory group and of the Board of Sponsors of the Bulletin of the Atomic Scientists. In his 1995 book, The Sun, the Genome and the Internet, Dyson asserted that solar power, genetic engineering and advanced communications technology offer the greatest potential for relieving poverty in the developing world.

In 2000, Dyson received the Templeton Prize for Progress in Religion. Dyson accepted the honor graciously, an act that gratified some religious believers, while annoying a number of his non-believing admirers. In recent years, Dyson has also attracted controversy with his contrarian statements on climate science. He has long accepted that human activity, particularly the burning of fossil fuels, is responsible for the accumulation of carbon dioxide in the atmosphere, warming the planet and causing long-term climate change. But he has urged his colleagues to remain open to other points of view, especially when it comes to strategies for responding to climate change. Dyson has advocated massive tree-planting to reduce the level of carbon dioxide in the atmosphere.

With all his other activities and interests, Dyson has continued to conduct significant mathematical research. In 2012 he produced a mathematical vindication of William Press's solution to the prisoner's Dilemma, an important concept in game theory, with serious implications for the debate over individual selection versus group selection in evolution.

At the end of his ninth decade, Freeman Dyson continues to write, speak and debate on a wide range of scientific and philosophical issues such as those addressed in his 2007 book, A Many-Colored Glass: Reflections on the Place of Life in the Universe. He has six children, including the science historian George Dyson and the journalist and technology entrepreneur Esther Dyson.