It was with immense sadness that we learned of the passing of Nicolas Bergeron on Thursday, February 15, 2024. Nicolas had been a Professor at the DMA since 2018.

Trained as a geometer, Nicolas combined great culture and curiosity with a profoundly coherent vision of mathematics. His work left its mark on topology, group theory and symmetric spaces, number theory and algebraic geometry. We recall his enthusiasm in recent months, his good humor and modesty as he shared with us the progress of his collaboration with Pierre Charollois and Luis Garcia. Their latest paper opens up a new path towards solving Hilbert’s 12th problem for complex cubic bodies.

Nicolas was very interested in the dissemination of science and the emergence of mathematical ideas and concepts. He took part in several audiovisual productions, including the film “Man Ray et les équations shakespeariennes” and the series “Voyage au pays des maths” on Arte-TV.
A proud member of the collective adventure of the Henri Paul de Saint-Gervais group, he contributed actively to the writing of the book “L’uniformisation des surfaces de Riemann” and to the creation of the Analysis Situs website. A fan of Jacques Roubaud and OuLiPo, his erudition went far beyond mathematics. It was thanks to him that Henri Paul de Saint-Gervais was appointed Satrape of the Collège de Pataphysique!

Nicolas Bergeron’s intellectual generosity, benevolence and commitment have made him a pillar of the mathematical community.
His investment in teaching in all its forms and in the life of the community, through scientific publishing and directing the IMJ-PRG and then the DMA, were essential. He took care and pleasure in guiding students at the École Normale Supérieure, never counting the hours.

Nicolas’ office was always open to students and colleagues alike. He brightened up the coffee room with his sense of humor and his chocolates. He will be greatly missed.