Michael Atiyah, a British mathematician who united arithmetic and physics through the 1960s in a method not seen because the days of Isaac Newton, died on Friday. He was 89.
The Royal Society in London, of which he was president within the 1990s, confirmed the dying however gave no particulars. Dr. Atiyah, who was retired, had been an honorary professor within the Faculty of Arithmetic on the College of Edinburgh.
Dr. Atiyah, who spent a few years at Oxford and Cambridge universities, revealed an unexpected connection between arithmetic and physics via a theorem he proved in collaboration with Isadore Singer, one of the essential mathematicians of the final half of the 20th century.
His work with Dr. Singer, of the Massachusetts Institute of Know-how, led to the flowering of string principle and gauge principle as methods to grasp the construction and dynamics of the universe, and has offered highly effective instruments for each mathematicians and theoretical physicists.
“He has closely influenced the entire up to date growth of how math and physics have interacted,” the physicist Edward Witten, of the Institute for Superior Examine in Princeton, N.J., mentioned in an interview for this obituary in 2015. Dr. Atiyah spent a superb a part of his profession on the institute.
Newton and his up to date Gottfried Wilhelm von Leibniz established the primary main bridge between arithmetic and physics by creating calculus and displaying that it may describe bodily attributes like velocity and acceleration. Dr. Atiyah and Dr. Singer found the same however much more delicate connection.
Dr. Atiyah was additionally energetic amongst scientists in selling peace. From 1997 to 2002 he was president of the Pugwash Conferences on Science and World Affairs, a corporation that brings collectively students and public figures with the goal of curbing armed conflicts around the globe. (It takes its identify from the positioning of its first assembly, in 1957, within the village of Pugwash, Nova Scotia. In 1995, the group and its founder, Joseph Rotblat, had been awarded the Nobel Peace Prize.)
Throughout his tenure at Pugwash Dr. Atiyah labored to defuse a nuclear standoff between India and Pakistan and to cut back tensions within the Center East. Earlier, as president of the Royal Society (1990-1995), he publicly criticized the British nuclear program, arguing that it was a harmful waste of scientific sources.
Dr. Atiyah acquired the 2 highest honors in arithmetic: the Fields Medal, in 1966, and the Abel Prize, in 2004. A number of colleagues of his have acquired Fields Medals for discoveries constructing on his work as nicely. He was knighted in 1983 and made a grand officer of the French Legion of Honor in 2011.
Dr. Atiyah, a comparatively brief and jolly man who had gone largely bald as a younger man, was famend for his vitality and a commanding voice, most notably in his lectures.
“He may hypnotize you into believing you understood one thing,” mentioned Graeme Segal, a former pupil of his and now an emeritus fellow in arithmetic at Oxford. “He would make you assume that every thing was potential, and there have been all these fantastic concepts, and you may put them collectively and do one thing with them.”
Michael Francis Atiyah was born on April 22, 1929, in London to the previous Jean Levens, a Scot, and Edward Atiyah, a Lebanese. His mother and father had met whereas his father was a pupil at Oxford. The household moved to Sudan, the place Edward Atiyah was a diplomatic liaison officer for the British colonial authorities.
Even with the daddy’s Arab ancestry and dedication to the Arab folks, the Atiyah household recognized culturally as British. Michael Atiyah spoke English at house and in school, and Arabic with prolonged household. (Written Arabic was the one class he ever failed, he mentioned.)
At 12, he went to the Victoria Faculty in Cairo, a widely known English boarding college, and at 16 he and his household moved again to England. At Cambridge, Dr. Atiyah did his undergraduate and graduate research at Trinity Faculty, the place he acquired his doctorate in 1955. That very same 12 months he married Lily Brown, who was additionally a mathematician. She died at 90 in March in Edinburgh. Dr. Atiyah was grasp of Trinity Faculty from 1990 to 1997.
Dr. Atiyah’s early work was in topology, a discipline of arithmetic that research form, together with that of mathematical objects with many greater than three dimensions. Although such objects can’t be visualized, topology gives instruments to determine what number of holes they’ve and the way completely different components of an object are related to at least one one other. Topology considers shapes to be elastic and malleable — in a position to be stretched or squished with out their elementary nature being modified, so long as no new holes are punched and no items are newly joined collectively. Working with the German mathematician Friedrich Hirzebruch, Dr. Atiyah developed a topological instrument referred to as Okay-theory.
Dr. Atiyah teamed up with Dr. Singer within the early 1960s. Dr. Singer is a specialist in mathematical evaluation, the examine of differential equations, that are used to explain bodily phenomena within the language of calculus.
The equations are extraordinarily helpful for describing real-world conditions, however they’ve a depraved drawback: Nobody is aware of the way to clear up them exactly. Dr. Atiyah and Dr. Singer got down to see if Dr. Atiyah’s topological instruments may assist discover the options.
Though they couldn’t discover the precise options to any differential equation, they did handle to make use of topology to disclose the variety of options such an equation has. This grew to become their well-known Atiyah-Singer Index Theorem, which they developed into a whole discipline, referred to as index principle.
“It’s a little bit of black magic,” Dr. Atiyah mentioned in 2015, “to determine issues out about differential equations despite the fact that you may’t clear up them.”
However that was only the start of the connections that the index principle would make. Within the mid-1970s, in the course of this work, Dr. Atiyah discovered one thing shocking: Physicists had been creating their very own, much less formal model of index principle in parallel with the mathematicians. They had been utilizing it to attempt to perceive quantum discipline principle.
Dr. Atiyah and Dr. Singer teamed up with the mathematician Raoul Bott and Dr. Witten, who was then barely out of graduate college. The group (and shortly many others) used index principle to see how discoveries in arithmetic revealed truths about physics, and the way bodily details revealed mathematical insights. Within the course of, they reworked each fields.
“It offers the entire panorama on which theoretical physics is constructed now,” Dr. Atiyah mentioned.
Dr. Atiyah’s survivors embody his sons David and Robin and three grandchildren. His eldest son, John, died whereas mountaineering in 2002.
Dr. Atiyah continued to affect younger mathematicians to the top of his life, and to experiment together with his personal mathematical concepts. In October, he created a stir when he claimed to have solved the Riemann Speculation, one of the well-known unsolved issues in arithmetic, however the proof didn’t maintain up.
Dr. Atiyah described himself as an optimist. In 2013 he advised a web-based interviewer: “I consider in new concepts, in progress. It’s religion. I’ve lately been interested by religion. In the event you’re a non secular individual, which I’m not, you consider God created the universe. That’s why it really works, and also you’re making an attempt to grasp God’s works. There are various scientists who work in that framework.
“Scientists, exterior of faith, have their very own religion,” he went on. “They consider the universe is rational. They’re looking for the legal guidelines of nature. However why are there legal guidelines? That’s the article of religion for scientists. It’s not rational. It’s helpful. It’s sensible. There’s proof in its favor: The solar does rise every single day. However however, on the finish of the day, it’s an article of religion.”