“I like math, because it explains the world”

Bringing nature and math together isn’t that amazing?

For me, not at all! I wanted to tell about my daily relationship with this discipline. My view of the world is first and naturally mathematical.

In this large willow that I adore, at the bottom of my garden, for example. On windy days, its long, flexible branches lift and move almost parallel to each other. In the wind, I see trees, but above all vectors, that is to say the segments of a line which indicate the direction, the direction and the force of a movement. It’s very concrete! You don’t need to be a scholar or a math whiz.

Do you really see them?

This happens to me all the time, because I like to understand the reality around me. This need for understanding undoubtedly led me to math, by allowing me to access abstraction. Faced with spider webs in my garden, I wonder about their spiral construction; when I walk in front of the sea, I count the seconds between one wave and the next, and I notice the fields of sinusoids on the expanse of water; in a tire track on the snow, I wonder if the curves can be perpendicular to a straight line…

Where does this understanding of the world come from?

My love of math comes from this need to explain the world. Understanding is beautiful and strong: we grope, we search and understanding comes like a light at the end of a tunnel. Often, I start with a question.

Take a rose and its petals curled into a spiral. Having read somewhere that the quantity of petals was always a number in the Fibonacci sequence, I wanted to check. And indeed, I counted 21, a number which is part of the illustrious Fibonacci sequence. This 13th century mathematician discovered a sequence of integers in which each is the sum of the two preceding it: 0, 1, 1, 2, 3, 5, 8, 13, 21… Fascinating, isn’t it? not?

And also your father?

My father worked at La Poste to pay for his studies, before becoming a physics professor. The moments we shared were often devoted to scientific explanations. Like when storms occurred. As soon as the sky darkened, I asked him for an explanation. Potential difference, ionization, electric discharge… I didn’t miss a thing.

My father knew how to explain why the sky splits and the air cracks. The magic was not in the weather, but in the knowledge. His power to explain fascinated me. Even today, at 90 years old, he warns me when storms are forecast.

What relationship do you have with nature?

I grew up on the fifth floor of a public housing building surrounded by vast grassy areas, next to meadows with cows. We couldn’t afford to go on vacation.

My appetite for nature comes from my mother, capable of instantly stopping an activity to contemplate a daffodil or a butterfly. She took me into the forest to find the first snowdrops, blackberries, mushrooms…

I discovered the seasons when I lived in my first tiny house. Today, my life has three dimensions: the mind with math; sensoriality with nature; and the heart with love.

And spirituality?

I wonder. I was raised Catholic and there is a small cross in my house, a statue of the Blessed Virgin. I find faith purely intimate and personal, more connected to an inner life than to a religion. Mathematics helps us get closer to infinity. They guide our thinking without ever imposing limits. So you never know!

Doesn’t explaining nature scientifically take away its magic?

Quite the contrary, because it turns out to be so complex and so well arranged! The magic is reinforced because by understanding how physical phenomena work, I feel closer to them. I am amazed all the time. We must not forget to take advantage of what is, like nature, beautiful, bearer of hope and universality. It also shows us the importance of being useful to each other.

What do you like about mathematics?

In sixth grade, the teacher explained the sets to us and I found it wonderful. This universe seemed extremely reassuring to me. Mathematics forms a bubble. Like nature, they allow me to put my thoughts to rest.

Few other things achieve this for me: feeling the love I have for those close to me, watching a film, walking in the garden and doing math are the only moments when my mind manages to anchor itself in the present moment . Then there is no more noise in my head. I was diagnosed with attention deficit hyperactivity disorder (ADHD).

You even mention the “ beauty » math…

Yes, they are harmonious, natural, dynamic, playful, creative. Each foray into mathematical territory can change us, make us even more alive, more awake, more independent. They are also emancipatory because we build what we want. The poetry of mathematics describes a tailor-made universe, adapted to each person.

But they obey precise rules, all the same…

At school, we learn Euclidean geometry, that is to say in a “flat” space, that is to say without curvature. But there are a multitude of others. This idea that there are different worlds is very liberating. The whole question is to dare. I think that those who suffer in math lack the ability to get started, the desire to take a step into the void.

To access the beauty of this discipline, you must agree to think, imagine and venture. Often, we don’t know where we are going and if we will succeed in completing the path we have chosen. I’m not afraid because I always feel held back by an invisible elastic band. So at worst, I would fail, it’s nothing serious. This elastic was passed down to me by my parents, a kind of emotional trust.

So you are one of those rare math teachers who understand that we can get stuck when faced with equations?

Oh yes! I chose math because being able to unblock a student when faced with a problem or an equation seems so rewarding to me. You see the light come on in his eyes and a world open before him!

But why do some students get stuck?

I think abstraction makes discipline difficult. Furthermore, in France, we perceive this subject as elitist, so many think that if they are not good, it means that they are not intelligent. Which triggers stress which itself prevents you from succeeding. When we encounter difficulties, we feel worthless, we reject them.

At 17, one in two girls no longer studies mathematics, compared to only one in four boys*. For what?

There are very few female figures in mathematical laboratories and they are not very present in the media. They feel less legitimate than boys. This has to change, of course.

After being a teacher, you have just been appointed class coordinator for children with disabilities. Is it a challenge to teach math to students of heterogeneous levels?

It’s the greatest challenge. Teaching is a true vocation: when I first started school, I told my mother that I wanted to become a teacher! I am very attached to school: even if it does not always work well, I like to know that there is a space where we can learn, transform ourselves, access things we ignore…

School is a place where everyone goes, and I like the idea that it allows us to “create a society”, a society that is committed to including everyone and forgetting no one.

*Mathematicians. Girls, future of mathematics, Ed. CNRS, January 2024.