03/08/2021

Ellenberg and Belotto mark the second day of the 33rd CBM.

After opening with a record audience of 2,440 registered participants, the second day of the 3Tuesdays Brazilian Mathematics Colloquium (CBM), this Tuesday (3), was marked by lectures with new perspectives, relaxation and an audience from various parts of Brazil and the world.

In the virtual audience, which follows the programming through The Colloquium was held on YouTube and via Zoom, with participants from different parts of Brazil and the world, ranging from the municipality of Quatipuru, in Pará, and Porto Alegre, in Rio Grande do Sul, to cities in Germany and Portugal, and Buenos Aires, in Argentina.

The day began with the introductory lecture “ On the regularity of geodesics in sub-Riemannian geometry ,” by the Brazilian mathematician André Belotto, from the University of Aix-Marseille. With many practical and didactic examples, Belotto explained the behavior of geodesics, the curves that minimize the distance between two points, under the constraints of sub-Riemannian geometry, the focus of his lecture.

To do this, Belotto used illustrations of these curves in situations such as a car maneuvering and even answered the problem of Queen Dido – a legend about a queen who traveled to North Africa via the Mediterranean, widely used in physics and mathematics – through a geodesic.

In the afternoon, it was the turn of American Jordan Ellenberg, from the University of Wisconsin, to give the second plenary session of the 3Tuesdays CBM. Also in a very relaxed manner, Ellenberg spoke with the virtual audience about the topic of his lecture, " Upper bounds for rational points" . Winner of the 2015 Guggenheim Foundation award, Ellenberg is also the author of the bestseller "The Power of Mathematical Thinking: The Science of How Not to Be Wrong", published in Brazil by Zahar and translated into dozens of languages.

In his lecture, Ellenberg made a point of highlighting that the Brazilian version was the first to be released outside of his country. “Brazil was the first country to show interest in my book, so it’s always good to visit IMPA. This is my second 'visit'. The first was in person, and I hope the next one will be too,” said Ellenberg, who spoke to the audience about algebraic geometry and number theory.

The lectures from this Tuesday (3) are available on the Colloquium's YouTube channel . The event's program continues throughout this week, with more plenary sessions, lectures, announcements and courses. Don't miss it!