Freeman Dyson (1923-2020): all-rounder without a doctor’s degree

With Freeman Dyson, who died last Friday at the age of 96 in his hometown of Princeton, the world has lost a multifaceted scientist and an astute observer of the human spectacle. At a symposium for his ninetieth birthday it seemed that there was a multiple personality disorder. There were sessions on number theory, particle physics, space travel, evolution theory, extraterrestrial life, climate change and nuclear disarmament.

As Dyson himself said: he was a frog, not an eagle. He enjoyed sitting in a pool enjoying the mud, after which he jumped to another pond. The elevated bird’s eye view was not spent on him. In the Netherlands he became known for his many books and a performance in the VPRO series A wonderful accident from Wim Kayzer.

Freeman John Dyson was born on December 15, 1923 as the son of the British composer and conductor Sir George Dyson and the lawyer and social worker Mildred Atkey. During the war he studied mathematics in Cambridge. His mathematical gifts were quickly recognized and used in the British bombing of Germany. This war experience gave him a lifelong guilt and made him a convinced pacifist.

During a post-war visit to the United States, he met a group of young American physicists. They returned from Los Alamos and wanted to solve the riddles of quantum theory. Among them Richard Feynman, the most idiosyncratic and brilliant of the bunch. It clicked immediately.

There were then two different approaches to particle physics. Julian Schwinger had drawn up a complicated calculation scheme that few understood. Feynman, on the other hand, stated a deceptively simple drawing scheme. During a long bus trip in 1948 from the west coast to Princeton, where Robert Oppenheimer had offered him a job at the Institute for Advanced Study, Dyson experienced his aha moment. Feynman’s diagrams accurately depicted Schwinger’s abstract algebra.

The birth of modern particle physics was recognized with a Nobel Prize for Schwinger, Feynman and the Japanese Shinichiro Tomonaga, who had independently found a third way. Dyson, who had brought everything together, just fell out of the boat. But, as he would say later: it is better to ask why you didn’t win the Nobel Prize than why you did.

Lifelong in Princeton

Apart from a trip to Cornell, Dyson would stay in Princeton all his life. Until last week he walked to his office every morning. He felt that he had shattered Oppenheimer’s confidence because he would leave particle physics. It was time for another pool.

He focused on designing nuclear-powered rockets. Destination of project Orion was nothing less than Saturn. Dyson was one of the few who was disappointed by the limited ambition of the moon landing. In the 1960s he became intensively involved in arms negotiations with the Soviet Union. He was also one of the first to think seriously about the search for extraterrestrial life. To be Dyson sphere has become famous. If a civilization reached the pinnacle of technology, it would capture all the energy of a star by surrounding it with a giant sphere that will be visible through heat radiation. He also fantasized about the colonization of the cosmos, through self-replicating robots or a spacecraft with the genetic material of all terrestrial organisms.

In the meantime, he devoted himself to his first love: mathematics. His ideas managed to reach the most abstract corners of number theory.

Science fiction story

Dyson also started writing in the 1970s. He was an author long before he became a scientist. At the age of nine he wrote his first science fiction story, about the small planet Eros that threatens to collide with the earth. Books are known for a wider audience Disturbing the Universe (1979) and Infinite in All Directions (1988), and the many articles for the The New Yorker and The New York Review of Books. His latest article, about dark matter, appeared in the January issue. In 2018 he published his autobiography Maker of Patterns, almost entirely composed of letters that he sent to his parents. The 19-year-old Dyson sounds just as sharp and serious as the 96-year-old.

Also read the book review: Frank self-portrait of the free physicist Freeman Dyson

Even though he has about twenty honorary doctorates, Dyson has never obtained a true doctorate degree. His career went too fast to put on that intermediate station. As an eternal PhD student, he had a free ticket to pursue every interest. He always did that with a cross, rebellious view. We joked: if you want Freeman to agree with you, surround him with opponents. This contradiction also brought him criticism. Many colleagues were disappointed that he turned out to be a climate skeptic. Not that he denied the role of man in global warming – he had been at the forefront of modern climate studies even in the 1970s – but he felt that the importance was overestimated. He also wrote unrestrained about the role of magic and expressed skepticism about the necessity of a “theory of everything” in physics.

Dyson had the remarkable gift of being in the right place at the right time. For example, he met Feynman at the height of his creativity and he was in Moscow just after Stalin died. He saw Dr. Martin Luther King, Jr. made his famous speech in Washington and visited film director Stanley Kubrick on the 2001 set: A Space Odyssey. Dyson was the scientific version of Forest Gump. When I noticed this, he responded spontaneously: “But I never met Forrest Gump!”

What is the secret of such a productive life? It reminds me of an interview with Leonard Bernstein. After a wide-ranging discourse, Bernstein says: “I no longer know what the question is, but the answer is” yes. ” Dyson always said yes. Against science and against life.

Robbert Dijkgraaf is director of the Institute for Advanced Study in Princeton.

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