Meet the 'Lady Gaga' of the maths world, Cédric Villani

At 42, mathematician Cédric Villani is something of a rock star. He is not just a prodigious mathematician – he won the Fields Medal, the most prestigious award in mathematics, in 2010. Since then, he has been travelling across the world to deliver public lectures and to advocate for mathematics in countries without the infrastructure to support it, particularly in Africa. He has also written a comic book in French.

Villani has another claim to fame, in part because of his distinctive personal style, which includes a three-piece suit, a flamboyant cravat knotted into a loose bow and a giant spider brooch. This has won him the unusual second distinction of featuring in photo shoots and on the covers of French fashion magazines.

The New Yorker referred to him as the “Lady Gaga of French mathematicians”. The Guardian called him "Lord Byron on a mini break."

Villani received the Fields medal from Pratibha Patil in Hyderabad in August 2010. Exactly six years later, he is in India again, this time to deliver lectures in Mumbai, Bengaluru and Kolkata.

Perhaps as a concession to the heat, Villani had dispensed with his waistcoat, but the rest of the much talked of ensemble remained intact, including a giant spider brooch crafted from silver and amethyst – a gift from friends in Uruguay, he said.

Mathematics, Villani said in an interview to Scroll.in, is not about calculations. It is about making connections. That ability to draw connections is what has defined his work and what won him his award. His talk at the Tata Institute of Fundamental Research in Mumbai on Friday, titled Of Triangles, Gases, Prices and Men exemplified this.

His work links the idea of the speed of fluid dispersal – that the rate of dispersal of particles when released into a vacuum always increases – to the Soviet-developed theory of optimal transport – that it is possible to mathematically determine the most efficient way to allocate resources from one location to another.

In conversation with Scroll.in, Villani spoke about communicating about mathematics, the infrastructure needed to develop it, and the surprising India connection he discovered while researching for his comic.

Edited excerpts follow:

What makes mathematics beautiful to you?
Mathematics is a science of understanding, of reasoning, of finding the truth and universal laws. Mathematicians are always happy to find beautiful connections and reasonings. That is what we live for. My public lectures explain and try to make the audience feel about one unexpected connection. But mathematics is many things at the same time. It has become tremendously useful for the technology and all the digital applications and so on. It has changed our whole way of thinking, in a way it is a contribution to philosophy. It has changed our representation of the world, etc.

You have spent these years since winning the Medal communicating to lay audiences about mathematics. How do you go about doing that in a way that makes it not just accessible but to build appreciation?
You are very right to distinguish between several things. When I go and do public lectures and so on, it is not a math course. A math course has to have some level of difficulty. Students have to work and make an effort. On the contrary, in an outreach talk, you want listeners to have a good time, like watching a movie. So public communication is and has to be about playing with the audience and telling stories and games. I developed a number of stories which I tell about my experience, about what happened in the world and history, some adventures. I always say history has to be about stories of people, of projects and of ideas. These three should come together. These are threads that will be woven together.

You’re also working on a comic book, isn’t it?
Oh, yes. I published the comic book last year in France. It was called – in English, it would Moonshine Talkers. It has been translated only in Spanish and Romanian at present. Talking moonshine is a mixture of talking big dreams and trying to be a crook.

It is a historic scientific graphic novel about the Second World War achievements and the role of science and technology in this. It is about the responsibility of science and technology in its use. The concept of the book is that these are the inner thinkings of four people who had an important role in the shadows in the second world war. One is the physicist Werner Heisenberg. Another is the mathematician Alan Turing. There is a physicist called Leo Szilard, who was at the start of the atomic bomb project, and the fourth is the British general Hugh Dowding, who was the coordinator of the Battle of Britain.

These four are seen at very emotional moments in which they recall their role for themselves or for other people, and about their legacy. It was a very enjoyable process, the collaboration with the artist. Maybe in the two or three past years, this was the one that gave me the biggest joy.

Szilard actually wanted to come to India to follow his secret love Gerda [Phillipsborn], a German girl who went in an orphanage to care for children. One of the children she took care of became the president of India later. [Note: she befriended Dr Zakir Husain, later the president of India.] He wanted to follow her – he was madly in love with her – from Berlin, but somehow the Indian university he applied to rejected his application. He was one of the best in the world, you know, but they preferred to hire some Indian.

Did he ever reunite with his love?
No, they never saw each other. He married another youthful love called Trude. The story of his secret love was uncovered by a physicist [note: Gene Dannen] only a few years ago.

Related to Szilard being rejected by an Indian university, what kind of infrastructure do you need to nurture mathematics, particularly in places without immediate access to centres or other mathematicians? How do you ensure that that talent or creativity does not get lost or obscured?
Traditionally, the very first thing you need is a library. In the old days, the biggest mathematical schools went with libraries. Like Alexandria and so on. Now things have changed because of the internet and because everything is accessible, but still you need a good connection. In many countries of the developing world – I am thinking of Africa for instance – internet access is a problem and so is access to science.

Then you need the people. That means people you can talk to and usually it takes a long amount of time to build this. Gather people, build them and make sure your place becomes a reference. You don’t just buy this with money. I will not quote names but there are very rich countries that have embarked in the past decades on building big universities with lots of money and high salaries and so on. It doesn’t work. It is not sufficient. People want to come to a place because they find the people with whom to talk.

The material needs of mathematics institutes are not much compared to other sciences. Then it is just about salaries and money for travel. But it is not that easy because it is usually tricky to convince and recall what it is used for. When you say to a politician, I need one million to buy this equipment to help make big experiments, the politician says ok, one million is a lot of money but we can see what is the result – the big equipment – and can do some nice inauguration. But if you say we need salaries and travel money so that there can be a good bunch of articles – what will I do with the articles? So it is more difficult to convince people even if the amounts of money are not so big.

Do you find back in Europe that there is still that kind of drive to go out and speak to people from countries that are still building their research programmes?
Now, going for six months is very difficult. People don’t travel on such time scales. It is gone. Everything has become faster and faster. The conferences, etc are shorter, it’s everywhere. We are more busy and in more of a hurry everywhere. Also, worldwide, there have been some evolutions when the biggest challenges have kind of shifted.

The biggest challenge by a long shot now remains Africa. It is a huge continent, totally undeveloped in terms of mathematics, with a very few exceptional individuals here and there. In each country we can find sometimes just one world class mathematician and there is quite some desire of the community to help. It is not easy.

Mathematicians build on the traditions of those who come before them – do you notice differences in the way Indians think about mathematics or Europeans or people from Africa? Are there cultural differences in the approaches to the science?
If I take a worldview, what is most striking about India is that there are some subjects in which the Indian school is very highly regarded. One of them is subjects at the interface of computer science and algorithmics and mathematics.

In India there is a tradition from time to time of some very exceptional individuals. Of course Ramanujan is the most famous, but in my area I can see closely SRS Varadhan [note: known for his work on his unified theory of large deviations]. He has a way of very original thinking nobody can understand. His papers – we don’t understand how it was done.

It is not that [Indian mathematicians’ work] does not fit into already existing frameworks and institutions. People in Paris go to École Normale Supérieure from an early age. We know about the problems of each other. We are mainstream from a very early age.

Corrections and clarifications: A previous version of this story erroneously referred to Zakir Husain as India's vice-president.