On Friday, November 18, Etienne Ghys will be awarded the CNRS medal for his initiatives in Popular Science. While he admits that he owes his recognition more to his publications than to his involvement in popular science activities, these are nevertheless very important to him. He would like to break out of the long-established dichotomy between good researchers and good popularizers, who make science attractive to the public. What if they both go hand in hand?

Q: Where did you get this appetite for Popular Science?

A: Actually, I've always been involved in popular science, even if I wasn't aware of it initially. My first popular science initiatives date back to my work in the journal "Images des mathématiques" which I helped to relaunch in its digital version in 2009. But long before that, I was always aware that if you are not able to explain what you do, it is because you do not really understand it yourself. So, I proceeded first with my students and doctoral students, then I widened the circle. From 1993-94, I gave many lectures to high school teachers, then, by virtue of concentric circles, I sought to go beyond the framework of professional mathematics. One day while filling out my “CRAC” (an activity report), I finally had the satisfaction of being able to check the box "How many films have you made?". I’m referring to my film “Dimension” released in 2010.

Q: How do you get into Popular Science exactly?

A: I realized very quickly in my career that I needed others to understand. For the record, the idea of making the film Dimension came to me during a meeting with a computer engineer, Jos Leys, who helped me upload images for a conference I was preparing for the BNF in 2006. I contacted him again some time later to prepare a lecture that I had the honor of giving at the International Congress of Mathematicians. We came up with the idea of illustrating the conference with small extracts of animated images of about fifteen seconds; it was a real success. When I wanted to thank Jos Leys, he asked me to explain what was in these images. And finally, by explaining the content of the images, I understood things better myself and at the end of our conversation, I had the idea of filming Dimension!  It’s as simple as that, we get into popular science by explaining, sharing, and it brings you so much happiness because we learn so much from others too.

"Popular science also means explaining yourself to yourself!"
I would add that on the centenary anniversary of Poincaré's death, when I produced podcasts from his lectures, I also realized that by reading aloud, I sometimes became aware of what I did not understand. So, I'd stop the recording, I'd read it again until the text really meant something to me, and I'd go back over it again and again until I was happy.

Q: Why do you think popular science initiatives need to be developed?

A: They need to be developed for the future of mathematics and more broadly the future of science! Today, mathematics has become so complex that even within the discipline, mathematicians can no longer understand each other. One could imagine that tomorrow there will be algebraic mathematicians, geometric mathematicians and mathematicians who do popular science! Communication tools within one subject area, and between different fields of study, have become as important as the content that constitutes them.
I think that popular science must be developed at all kinds of levels, and with many audiences, scientists amongst themselves, or with scientists and secondary school teachers for example. Otherwise, disciplinary content is at risk.

Q: For a long time, there was a hierarchy between researchers who published and researchers who worked in popular science. Is this still the case?

A: Things are changing, slowly, but they are evolving. The proof of this is this medal for popular science launched last year by the CNRS. The CNRS has also set up a Research Group, called Audimath, which brings together the network of all popular science in mathematics.
However, to convince our institutions that popular science is a noble activity, there is still a long way to go! Institutions must structure themselves and provide the means so that popular science initiatives are not "an extra on top of everything else” but are recognized as true initiatives in the work of researchers. This will involve specific training, recognition for careers in this field and an assessment of popular science skills. Right now, we are not very advanced on these last two points.

Q: Beyond your productions or publications of popular science books, is there a media initiative that you are particularly proud of?

I am very proud of what we have been able to do at the MMI (Academy of Mathematics and Computer Science created as part of the laboratory of excellence known as Milyon Labex). This type of place does not exist elsewhere, we must allow it to continue and even increase its activity, with schools as well as the general public. It is a place that aims to bridge the gap between the world of research and education and that is very important.

Etienne Ghys, production by a mathematician in popular science

- Images des mathématiques
- Dimensions
- La Théorie du chaos, Paris, De Vive voix, 2010 (ISBN 978-2846841078) — CD audio, coll. « L'Académie raconte les sciences »
- Film Chaos
- Maison des mathématiques et de l’informatique (MMI)
- La Petite Histoire des flocons de neige, Odile Jacob, 2021, 144 p. (ISBN 978-2-738-15441-5)
- "Étienne Ghys, les maths montées en neige", France Culture, La Méthode scientifique broadcast, March 18, 2021