4 December 2025

1:30 PM – 2:15 PM

Amphi Grand Kursaal

Roger Mansuy

After a thesis in probability, Roger Mansuy chose to teach in scientific preparatory classes. In addition to teaching at the Lycées Louis-le-Grand and Saint-Louis, he is well known for his efforts to promote mathematical culture, having published a dozen academic works and written monthly columns for the magazine La Recherche.

And in the limit, we find π?

Archimedes’ constant or the circle constant has fascinated mathematicians from different cultures for millennia. We learn in school textbooks that humanity was able to estimate it precisely very early on; however, this statement hides some unsaid things about passages to the limit; through this mathematical stroll, we will seriously examine some seemingly crazy statements such as “π is 2”, “π is the smallest value of π” or “π is between 3 and 4 and we can’t say anything better”.