Until this year, Cédric Villani, Ph.D., was a world-class scholar, a man affectionately nicknamed “the Lady Gaga of French Mathematicians,” and the flamboyantly dressed genius behind the TED talk, “What’s so sexy about math?” But on June 18, the dapper academic added another title to his impressive resumé: Politician.

Villani, a member of new French president Emmanuel Macron’s centrist En Marche! party, was recently elected to the lower house of the French Parliament to represent a group of southern Parisian suburbs.

It’s a big change for the mathematician, who has no political experience and until recently has stayed largely within academic spheres. In 2010, he won the Fields Medal, the world’s highest prize for mathematical research, awarded to researchers under the age of 40. Since then, he’s become one of the most famous and visible scientists in France.

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One of many Gaga-esque portraits on Villani's personal website.

Has popularity might have as much to do with his efforts to evangelize mathematics as with the sartorial habits that earned him his Lady Gaga nickname: He’s known for wearing a three-piece suit, a watch chain, a velvet cravat, and a dramatic brooch drawn from “his collection of more than 30 customized brooches.” But it’s his work on the mathematics of particle motion through space that earned him the respect of his fellow mathematicians.

In particular, he solved a fundamental problem of how particles move within a cloud. While mathematicians have known since Ludwig Boltzmann first explained it in 1872 that the smooth, even, predictable behavior of a gas cloud is an emergent property of millions of random particle events, they didn’t have a rigorous understanding of how those particles behaved in the in-between state — those moments between cracking a gas canister and when the cloud spreads to fill the whole room. Villani showed just how the randomness, or entropy, of particles increases, and then created formulas for tracking that increase. Later, he even found a key exception to Boltzmann’s rule — showing how a plasma, where particles don’t collide, can move to evenly fill a space without increasing its entropy.

But whether his mathematical prowess says anything about his ability to handle the challenges of political life remains to be seen.

entropy
A gas cloud will fill a whole space, even though its individual particles behave randomly.

He’s made it pretty clear that his skills extend beyond the acadmic bubble. Even before running for office, Villani had largely left full-time research. He directs the Institut Henri Poincaré, a mathematical research institute, and spends his time trying to serve as an ambassador for mathematics to the public. His book, Birth of a Theorem: A Mathematical Adventure, explains the process of developing a deep mathematical insight. He also gave a TED Talk in 2016, during which he argued, with some success, to his audience that math is “sexy.”

In interviews, Villani has said that he was not interested in politics before running for office. But Macron’s pro-Europe, pro-science platform appealed to him, and he joined En Marche! as a candidate in the hope of bringing “scientific expertise” to governance.

En Marche!, a brand new party in the French political landscape, took home a landslide victory in the June elections, securing 308 of 577 seats in the legislature. So Villani, Macron and co. will have an opportunity to put that expertise to the test.

Photos via Greg via Wikimedia Commons, CedricVillani.com