05/11/2019

Wearing flip-flops, Briton Robert Morris performs a combination of techniques.

Cecilia Manzoni

In the historic city of Lancaster, in northwest England, a scene frequently repeated itself in the Morris family home. As the children were putting to bed, Jim would create a cozy atmosphere and begin telling stories, only to be interrupted by a categorical plea. “No stories, Dad! I want math!” demanded Robert, the youngest son. Over time, his passion for mathematics reached new heights. At 15, the teenager channeled his energy into solving complex mathematical problems, and at 17, he won a bronze medal at the 39th International Mathematical Olympiad (IMO).

Robert Morris, a researcher at IMPA since 2010 and winner of the 2017 SBM Prize, works in the field of combinatorics, focusing on probabilistic combinatorics and applications of the probabilistic method in areas such as Ramsey theory and number theory.

Combinatorics, a field of mathematics that studies finite sets of elements that satisfy specific criteria, began to expand in the 20th century with the work of the Hungarian Paul Erdős. The area is basically divided into probabilistic combinatorics, which studies the typical properties of finite and random objects; and extremal combinatorics, which studies the extremal properties of these objects. These objects can be sets of numbers, graphs, colors, geometric objects, among others.

“Combinatorics is very different from other areas of mathematics. The difficulty in reaching the frontier of the field is much lower. I could explain a problem on the board that anyone could understand in 10 minutes. The process of solving problems in the field is not necessarily time-consuming, and sometimes a problem that seems unattainable may have a very simple solution that has never been addressed,” says the mathematician.

This simplicity also sets the tone for the lifestyle led by the Briton, who is slowly transforming into a true Carioca (Rio de Janeiro native). Morris, who says he feels alienated from English culture, found in Brazil the relaxed attitude he lacked. His flip-flops have become his trademark. "I'm known in the combinatorics community for going to all the conferences in flip-flops," he jokes.

A career in mathematics was never in doubt. When he graduated in the field from the University of Cambridge, he didn't hesitate to pursue a master's degree in mathematics at the same institution. After completing the course in 2001, his plans involved a gap year traveling through Latin America, Australia, and New Zealand.

An unexpected encounter with students of Professor Béla Bollobás, currently a special visiting researcher at IMPA, in a pub in Glasgow, Scotland, resulted in an invitation to pursue a doctorate at the University of Memphis (Tennessee, United States). Faced with the opportunity to work with a leading figure in combinatorics, plans to take a sabbatical were postponed.

“Adapting to Memphis was quite complicated. It’s a conservative city with many cultural differences, which made me become closer to the international students,” Morris comments.

It was during his doctoral studies that he visited Brazil, when Bollobás took his advisees to a combinatorics conference at IMPA in 2004. "I was completely fascinated and, after spending two weeks here, I was sure I would live in Rio."

The long-awaited move to the country happened quickly. Two years later, in 2006, as soon as he finished his doctorate, Morris came to IMPA for a postdoctoral fellowship. During this period, he immersed himself in Rio de Janeiro's culture, becoming a regular at "Forró de Rabeca," an event that enlivened the nights in downtown Rio de Janeiro.

He returned to England after a year for a postdoctoral position at the University of Cambridge. “I thought it would be a good professional opportunity, but I was very sad to go back. I no longer felt like I belonged to that culture. On the other hand, the University of Cambridge was quite flexible regarding travel, so I had the opportunity to spend time doing research in Tokyo (Japan) and Tel Aviv (Israel).”

His permanent move to Brazil resulted from an invitation to become a researcher at IMPA in 2010. "In any case, I already spent every summer in Rio," emphasizes Morris, who lives in the country with his Honduran wife Karen and their two daughters.

Since then, the Briton has won the SBM Prize in 2017; the European Prize in Combinatorics in 2015; and the Fulkerson Prize from the American Mathematical Society in 2018, among other distinctions. An affiliated member of the Brazilian Academy of Sciences (ABC), he views scientific research as a pleasurable activity. “Spending an entire day in front of a whiteboard pursuing an idea to solve a beautiful and difficult problem is a lot of fun. It gives me a feeling of happiness.”

After dreaming so much about Brazil, Morris vows he's not leaving. And IMPA plays a big role in that. “I’m very happy with the institute. I consider it a perfect place to do research. We have the freedom to only teach in our area, excellent students, and this space in the forest makes a huge difference. If I get stuck on a problem, I go outside to admire the view, breathe, observe the monkeys and toucans. I return to the classroom refreshed and ready for a new attack on the problem.”