was pouring rain on a chilly spring day, and Artur Avila was marooned at the University of Paris Jussieu campus, minus the jacket he had misplaced before boarding a red-eye from Chicago. “Let’s wait,” said the Brazilian mathematician in a sleep-deprived drawl, his snug black T-shirt revealing the approximate physique of a sturdy World Cup midfielder. “I don’t want to get sick.” In everyday matters, Avila steers clear of complications and risk. Afraid his mind will veer from road signs and oncoming traffic to “unimodal maps” and “quasi-periodic Schrödinger operators,” he doesn’t drive or bike. “There are too many cars in Paris,” he said. “I’m fearful of some crazy bus killing me.”
Soon the conversation turned to a different kind of worry for Avila — that public reminders of Brazil’s apparent lack of intellectual achievement will discourage students there from pursuing careers in pure math and science research. In the lead-up to this summer’s World Cup competition, popular news websites and TV shows like “Good Morning Brazil” parroted the question: How has the world’s seventh-largest economy managed to score five World Cup titles but zero Nobel Prizes? (The British biologistPeter Medawar’s tenuous connection to Brazil — born there but raised in his mother’s native England — merits at best an asterisk.) Even Argentina, that bitter soccer rival with a population one-fifth the size of Brazil’s, boasts five Nobel laureates.
To Avila, the criticism stings. “It’s not good for the self-image of Brazil,” he said.
Even then, in May, the native son of Rio de Janeiro had a secret weapon, a compelling argument that Brazil belongs among elite math nations like the United States, France and Russia. But he could tell no one — until today. The International Mathematical Union has made Avila the first Brazilian recipient of the Fields Medal, awarding the 35-year-old what many consider the equivalent of a Nobel Prize in mathematics for his “profound contributions to dynamical systems theory” that “have changed the face of the field,” according to the prize selection committee.
“He has high geometric vision. He tells you what you should look at, what you should do. Then, of course, you have to work.”
“He’s one of the very best analysts in the world,” said Jean-Christophe Yoccoz, a renowned Collège de France mathematician and 1994 Fields medalist. Of the many talented postdoctoral researchers Yoccoz has advised, he said, “Artur is in a class by himself.” Most mathematicians focus on a narrow subfield and have a low success rate, Yoccoz explained, but Avila “attacks many important problems and solves many of them.”
His work “cannot be reduced to ‘one big theorem’ as Artur has so many deep results in several different topics,” said Marcelo Viana, who worked with Avila to solve a long-standing problem about the chaotic behavior of billiard balls. The two proved a formula that predicts which side of the table a ball is most likely to hit next — and which side it will likely hit after a thousand bounces, or a million, all with the same margin of error. By contrast, Viana observed, if you try to predict the weather, “you’ll get very good predictions for tomorrow, not very good predictions for the day after, and completely lousy predictions for 15 days from now.”
Months before today’s announcement on the IMU website, the Brazilian dynamicistWelington de Melo predicted that his former doctoral student would win math’s highest honor. “It’s going to be extremely important to Brazil,” he said. “We never before got such a high prize. It is especially important because Artur was a student in Brazil all the time.”
Math on the Beach
Two things Avila fears more than erratic buses are PowerPoint slides and income tax forms. The pressure to perfect a plenary talk for the thousands attending the 2010 math congress in Hyderabad, India, induced in him a kind of mental paralysis, he said. After giving a lecture at the California Institute of Technology in 2008, he declined an honorarium of more than $2,000 just to avoid the paperwork.
“I would get fired pretty fast from most jobs,” he said, adding that he sleeps well past noon and is “not good at managing time.”
But in mathematics, Avila has a reputation for diving headfirst into unfamiliar waters and rapidly solving a raft of ambitious open questions. His colleagues describe his working style as highly collaborative and freakishly fast and Avila himself as having a clear-minded intuition for simplifying deep complications.
“He has high geometric vision,” said Raphael Krikorian, an Armenian-French dynamicist at Pierre and Marie Curie University in Paris. “He tells you what you should look at, what you should do. Then, of course, you have to work.”
Now a globe-trotting dual citizen of Brazil and France, Avila spends half the year in Paris as a research director at CNRS, France’s largest state-run science organization, and the other half in Rio as a fellow at IMPA, Brazil’s national institute for pure and applied mathematics. (The Brazil-France connection is no coincidence; in the 1970s and 1980s, top young French mathematicians like Étienne Ghys and Yoccoz fulfilled their mandatory military service with a civil-service alternative: conducting research at IMPA.)
In balmy Rio during the summer and winter months, Avila mulls over problems while lying in bed or wandering Leblon beach a block from his apartment. There, he has more time and freedom to think deeply about his work and to let ideas flow freely. “I don’t believe that I can just hit my head on the wall and the solution will appear,” he likes to say. He sometimes invites collaborators to Rio one at a time for what can only be described as an unconventional work experience.
Thomas Lin/Quanta Magazine
Avila spends about half of the year in Paris, where he prefers walking over other forms of transportation.
“The last time I was in Rio, I specifically got a hotel near the beach so I could work with him,” saidAmie Wilkinson, a mathematician at the University of Chicago. After searching for Avila on a beach that was “packed shoulder-to-shoulder” with “oversexed cariocas” and returning to her hotel to try to call him, Wilkinson eventually found him “literally standing in the water,” she said. “We met and worked up to our knees in water. It was totally crazy.”
“If you work with Artur,” she said, “you have to get into a bathing suit.”
Avila was born to parents who could not envision their son growing up to become a pure mathematician — they had never heard of one — and wanted him to aim for a stable career as a bureaucrat. His father’s formal education growing up in the rural Amazon didn’t start until his teenage years, but by the time Artur was born, his father had become an accountant in a government reinsurance enterprise, able to provide a middle-class lifestyle in Rio for his family and buy math books for his quiet son, who early on was more interested in reading than imitating Pelé’s bicycle kick. When Avila was 6, his mother — who still files his tax returns — enrolled him at Colégio de São Bento, a conservative Catholic school known for its academics and for the gold-plated, 16th-century São Bento Monastery. Two years later his parents separated. As the years passed, Avila increasingly focused on mathematics to the exclusion of almost everything else — he often did poorly in other subjects and was expelled after the eighth grade for refusing to take mandatory religion exams. He said he “left the school completely unprepared for normal social interaction.”
Avila got his first taste of the wider mathematics community just before he was expelled in 1992 when Luiz Fabiano Pinheiro, a master teacher at São Bento affectionately known as “Fabiano,” encouraged the 13-year-old prodigy to participate in the junior division of the prestigious Mathematical Olympiad competition. Avila was excited by problems he had never encountered but felt woefully unprepared. “For the first time, I felt I couldn’t do anything,” he said. The next year, after Fabiano helped him transfer to a new school, Avila won top honors at the state level. Two years later, he took gold at the International Mathematical Olympiad in Toronto.
“The first time I met Artur, I knew that he would be pre-eminent,” Fabiano said in Portuguese as his ex-wife, Eliana Vianna, interpreted. “Artur was the best of all my students ever,” said the retired 72-year-old who taught for five decades.
Through the math competitions, Avila discovered IMPA, where Brazil held its Olympiad award ceremonies each year. There, he met prominent mathematicians likeCarlos Gustavo Moreira and Nicolau Corção Saldanha, and while still technically in high school, he began studying graduate-level mathematics.
Dynamical Systems
In Brazil, Avila could relish mathematics without the career pressures he might have faced in the United States. “It was better for me to study at IMPA than if I were at Princeton or Harvard,” he said. “Growing up and being educated in Brazil was very positive for me.”
A major focus at IMPA is dynamical systems, the branch of mathematics that studies systems that evolve over time according to some set of rules — a collection of planets moving around a star, for example, or a billiard ball bouncing around a table, or a population of organisms that grows or declines over time.
One reason that many young mathematicians are drawn to dynamical systems, several researchers said, is that the relatively new subject, unlike the ancient field of number theory, doesn’t require a great deal of prior theoretical knowledge to begin solving problems. And dynamical systems are everywhere in math and nature. “It’s like a glue that connects many other subjects,” Krikorian said. Of the “two cultures of mathematics” described by the University of Cambridge mathematician and 1998 Fields medalist Timothy Gowers, there are theory-builders who create new mathematics and there are problem-solvers who analyze existing questions. Most dynamicists, said Yoccoz, including Avila and himself, are problem-solvers. “Both ways are necessary,” he said.
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