Daniele Di Pietro: the maths aesthete

Daniele Di Pietro speaks a language unlike any other. Not Italian, his native tongue, but the language of mathematics, which brought him from Italy to Montpellier. Derivatives, partial differential equations, polytope methods—words that did not sound like music to his ears at the time. And for good reason: the current director of the Montpellier-based Alexandre Grothendieck Institute, named after another great mathematician, was originally destined for a career in computational fluid dynamics. However, he changed direction at the beginning of his thesis when he metAlessandro Veneziani, a mathematician passionate about his work who inspired his interest in numerical analysis.

"At that time, I also realized that without math, I wouldn't get anywhere, because I didn't have enough physical intuition to develop digital simulators," recalls Daniele Di Pietro. And that worked out well, because the young doctoral student at the time "clearlyhada knack for math. It's a formalized language that's used in all disciplines, because the first step in research is precisely to formalize a problem." Math? It's everywhere, the researcher reminds us, "in your computer, in your phone, everywhere." Universal and yet so complicated to share."Making ourselves understood by others by translating our research into everyday language is a real difficulty specific to mathematics and a real challenge. Even with our colleagues, we sometimes only understand each other 20% of the time: we speak the same language, but we all have different dialects."

Aesthetic dimension

Armed with this new passion, Daniele Di Pietro left Lausanne after completing his thesis to work in numerical analysis, arriving in France in 2007 where he found a post-doc position at the École des Ponts, quickly securing a research position at Ifpen. His career continued to grow exponentially, leading to an appointment as professor at the University of Montpellier in 2012, at the age of just 33, where he focused his research on the development and analysis of innovative numerical methods for partial differential equations. Mathematical research that takes on an aesthetic dimension in the words of Daniele Di Pietro: "I like to find beauty in mathematics, the kind that comes from an idea, a spark."

With more than 100 publications to his name, the mathematician and aesthete who has been directing IMAG for three years now is delighted with the appeal of a laboratory that has recruited four research directors since the start of his term, an exceptional situation. "Mathematical research is very active, and IMAG stands out particularly in terms of project submissions ," explains Daniele Di Pietro. And the latest is not the least: the researcher has just secured an ERC synergy grant, "the largest projects funded by the European Research Council, for which we have obtained €7.8 million, including €4.4 million for IMAG," says the laboratory director, who is accompanied by three other internationally renowned researchers: Jérôme Droniou from IMAG, Paola Antonietti from the Politecnico di Milano, and Lourenço Beirão da Veiga from the University of Milan Bicocca.

Tell a beautiful story

The NEMESIS project aims to develop innovative numerical methods for partial differential equations in order to design a more flexible approach to the numerical simulation of physical problems. "It's a project that's difficult to explain, because the multidisciplinary jury isn't made up solely of mathematicians: we had to make sure that everyone could understand it," explains the researcher, for whom writing a project proposal is a bit like telling a story. "To summarize, you have to choose the right elements, a bit like choosing the right characters to tell a good story in which you are, of course, the hero, since you are proposing to solve the problem presented."

To help people understand this large-scale project, the researcher also explains how it could be used. "Nemesis targets several applications, including magnetohydrodynamics, which is involved, for example, in aluminum smelting, and flows in porous and fractured media, which are involved in CO2 storage processes and in assessing the risks of nuclear waste storage."

Feminizing mathematics

Daniele Di Pietro is delighted with this exceptional funding, but also says that it "will keep him very busy. It's a huge project, and it's also a huge amount of pressure."The next step is to recruit around ten doctoral and post-doctoral students at IMAG to work on NEMESIS. "It's difficult, because we're looking for excellent, highly independent candidates: we need to find people of the very highest caliber."Male or female candidates? "Mathematics has long been a very male-dominated field of research, "acknowledges the researcher, " but in recent years, the discipline has been catching up considerably in this area and the field is becoming much more feminized," explains the director of IMAG, with a clear desire to ensure equal opportunities for men and women. "Of course, our primary recruitment criterion remains excellence. But, at the same level, we give preference to hiring women in order to catch up in terms of gender parity."

The next major challenge facing the director of IMAG will be accommodation. "To accommodate the new recruits, we're going to have to push back the walls." While waiting to launch this major recruitment campaign, which will begin in January 2024, the mathematician has made an initial investment that takes pride of place on his desk: a very large screen. Has he abandoned the blackboard that feeds the stereotypical image of the mathematician writing equations incomprehensible to the average person? "I have to admit that the image is partly true, but I'm allergic to chalk," confesses Daniele Di Pietro. This peculiarity keeps him away from the blackboard, but it hasn't stopped him from proudly adding this ERC to an already impressive list of achievements.