"Survivors of a Dying Era": Cédric Villani on AI, the Navier–Stokes Announcements, and the Future of Mathematics

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Overview

In a conversation recorded in France, Takahiro Anno asked Fields Medal–winning mathematician Cédric Villani what the recent wave of AI results in mathematics means, especially the September 8 announcements from Anthropic and OpenAI on the Navier–Stokes problem. Villani's position is that mathematics has gone, within a single year, from the science least affected by AI to the one most affected. He calls the AI results technically remarkable. He also sees the companies' motives as advertising and power, and the consequences for authorship, students, and academic independence as deeply worrying. He says nobody, including himself, knows where this is heading.

21 min read
10:39

Why the big companies invest in science

Villani began by saying the debate about AI in science cannot be separated from the wider debate about culture and society. He argued that the large AI companies do not invest enormous sums in science for direct return on investment. Their first motive, in his view, is advertising: "we solve the science problem, so we are so good." He pointed to how, after the Navier–Stokes announcement, the whole planet was talking about OpenAI solving a mathematics problem. Their second motive is training: working on very hard scientific problems forces the company to become very good at everything else.

He backed this up with a story from a friend at one of these companies. The friend works on a large scientific program in meteorology, using AI to forecast tornadoes and other events, and Villani described the work as genuinely good. According to the friend, the company's priority is always publicity. When he requests computing time, it goes first to publicity projects, and he gets access only when some capacity is left over. Villani granted that these companies have a scientific culture, since many engineers and scientists joined them as a second career. But he argued that "the love of science" is not the driving force. The primary goal is money and power. He recommended Karen Hao's book Empire of AI, which he described as an investigation into how the CEOs of large AI companies see the world and into their thirst for power.

13:07

From least affected to most affected in one year

Villani's second point was about speed. Had they met a year earlier, he said, he would have told Anno that mathematics was probably the science least affected by AI. Now he would say it is probably the most affected.

His explanation was that the first wave of AI was dominated by statistics: gather as much data as possible. Empirical knowledge was therefore what AI "ate up" first. Mathematics is largely about rules, so it was relatively protected. Mathematicians do some empirical work, but far less than physicists, chemists, or doctors. A year ago, he would have named medicine as the most affected science, because so much of it is empirical. A treatment works without anyone knowing why, perhaps because of a patient's ancestry or some other factor, with no understandable rule behind it. Now that AI can understand and incorporate rules, mathematics is very strongly affected.

14:42

Proof search, Lean, and a hundredfold speedup

Villani described AI proof generation as combining two mechanisms. The first explores possibilities of reasoning: drafting, trying combinations, and pulling bits of reasoning from many papers. The second checks the proof for consistency.

For the checking side, he gave historical background. Computer scientists and mathematicians, especially in France, worked for a long time on formal ways of verifying mathematics. The system was originally called Coq and has since been renamed (Rocq). A system in the same spirit, Lean, took over in the last few years. Villani called it a revamped version of an approach that began 20 or 30 years ago, and said it now has a huge community. Lean is the tool that verifies a line of reasoning is completely correct, and mathematics, by its nature, makes this kind of verification possible.

Villani said that over the past year alone, the speed of turning a mathematical statement into a Lean statement had increased by a factor of at least 100. His evidence was a conversation from the previous year with one of the main mathematician-developers working on formalizing Fermat's Last Theorem. That developer, "working like hell," estimated it would take him about two years just to formalize Wiles's famous paper, which is only one step of the full proof. Then, Villani said, Anthropic recently announced a formalization of the full proof completed in under two weeks. That comparison is where his figure of at least 100 comes from.

He added that this has caused resentment in the Lean community. He said something similar had already happened during the formalization of Maryna Viazovska's theorem. Lean contributors had worked openly with the goal of helping the community and empowering mathematicians. Now they see their tool being used very efficiently by giant companies to move faster than the mathematicians themselves. According to Villani, they "really feel they have been robbed."

17:48

The 2026 calendar: a month-by-month race

Villani then laid out a timeline. He said the first significant mathematical contributions from AI came in spring 2026. After that came a contest with roughly one new step each month. So far, he said, only two companies have really been in that league, OpenAI and Anthropic. Anthropic made the first move, OpenAI a bigger one, Anthropic a bigger one still, and so on.

The first result that people truly felt was on the unit distance problem: place n points in the plane and ask, asymptotically, how many pairs can be at distance exactly one. There was a conjecture about the maximum, and AI disproved it by finding families of configurations with very good asymptotic behavior. Villani said several people who had worked on the problem were surprised by the results.

In July, a conjecture he referred to as the Jacobian conjecture was disproved by AI, again on a problem many people had worked on.

In early August, just after the International Congress of Mathematicians, OpenAI announced ten fairly significant contributions. Villani praised the presentation. OpenAI did not just hand over raw proofs. Good mathematicians curated the results, explained why each was interesting, and provided summaries and complete checks. He called it "well done."

Then came Anthropic's announcement of the formalization of Fermat's Last Theorem, followed by September 8.

20:27

September 8: Anthropic, OpenAI, and Navier–Stokes

Villani told the story of that day from his own vantage point. Early in the morning, a friend messaged him that there would be a big announcement. The mathematician involved was Tristan Buckmaster, an Australian whom Villani knows well and describes as a very bright young specialist in fluid equations. Buckmaster was collaborating with Anthropic on significant progress toward the regularity problem. It was not the full Navier–Stokes problem but particular cases and related equations. Villani found it notable that Buckmaster's collaborator on the Anthropic side was not a fluid mechanics specialist at all. He was a Turkish mathematician specializing in algebraic geometry, a completely different field, but an expert in both mathematics and AI.

Villani said that when people at OpenAI heard about the work, they tried to lure Buckmaster to their team, proposing that he make the announcement with them and share credit for Navier–Stokes later. His friend was outraged. In Villani's account, the Anthropic side felt forced to publish immediately because of the OpenAI team's actions. The publication appeared about an hour after Villani got the message.

Shortly afterward, Terence Tao posted about it on his blog, calling it exciting news. Villani described Tao as super bright and dynamic. He received his Fields Medal very young and has been enthusiastic about AI in mathematics for years. Villani noted that Tao has a personal connection to this problem. His adviser was Stein, and he was very close to Charles Fefferman, who wrote the Navier–Stokes problem into the list of Clay Millennium Prize problems. Tao's post said the new result gave hope that the full Navier–Stokes problem might be solved later, though many difficulties remained. Villani also spoke with Buckmaster by phone, and Buckmaster explained the principle of the work to him.

A few hours later, OpenAI released its own contribution. Villani believes it had been ready beforehand. In his interpretation, OpenAI was continuing to improve it until forced to publish, then released it the same day to counter Anthropic. And it went much further: OpenAI claimed a full solution of the Clay Millennium problem, along with many other new results. Villani said it will take the community a long time to digest. He believes the project was done in a hurry with the clear aim of scooping Anthropic, and said that OpenAI succeeded.

24:36

The Euler result, which Villani considers more striking

Villani offered his own view of which result matters most. As a mathematician, he thinks the most significant part of OpenAI's announcement is not the Navier–Stokes result but the one on the Euler equations, the equations without viscosity. They were announced at the same time but were not part of the Clay prize. The technical reason he gave is that the Navier–Stokes result uses a particular forcing, while the Euler result needs no forcing. He described it as the solution to an implicit problem that has existed since the time of Euler himself, and called it "very, very striking."

He also noted that the result did not come from nowhere. Both the Anthropic and OpenAI teams built on an initial idea from a pair of researchers he named, somewhat tentatively, as Córdoba and Martínez. The AI work developed that idea and showed how far it could be pushed.

25:14

Priority disputes and the Fields medalists' statement

After September 8 came a priority dispute. People working with Anthropic voiced suspicion that the other side had taken part of their work. Villani said they even worried the other side might have had access to what they were doing through the software. He placed this in a pattern: over the past year there have been five priority disputes between humans and AI, each with someone claiming that work had been stolen or done earlier. He sees the rising number of these "paternity" cases as a sign of growing confusion over authorship.

Villani said he is working on a joint statement among Fields medalists. More than half of the living Fields medalists have signed a text warning of a "severe misalignment between the AI and the science." The statement raises concerns about authorship and the arrival of big money. On money, he gave a concrete comparison. The Clay Institute offered $1 million for the Navier–Stokes problem, and he believes the companies spent at least ten times, probably a hundred times, that amount on that single problem. Universities cannot compete with that. If staying at the top of research means signing large contracts with these companies, he asked, what happens to academic freedom?

27:12

"How do we motivate students to do a PhD now?"

Villani said that he personally does not use these tools, as a matter of principle, though he knows many people who do, including some very good mathematicians. He then relayed a message from a former student who is now a highly respected professor at Cambridge. According to that student, OpenAI's public model, not the private one used for the Navier–Stokes work, can automatically solve within a few hours any problem one would give at the start of a PhD, or even in the middle, roughly the level of the first two years. The former student's question was how to motivate students to do a PhD now. Villani's answer: "This is where we are."

He said mathematicians have been exchanging remarks like "we are like survivors of a dying era." He found it striking that the usual generational pattern is reversed. With most new technologies, young people are the ones eager to try them. Here, he sees older mathematicians saying it is fun to play with the tools, while young mathematicians react with alarm: this is big money, this is a war, what do we do now? He said he has heard of students literally crying at the thought that their whole career path is disappearing. In his summary, the mood shifted within roughly one or two months from "very exciting times" to "very threatening times."

29:39

Exponential or sigmoid?

Anno asked whether the explosion of AI-generated proofs would keep going or saturate. Villani said: "Absolutely nobody knows." Nobody knows whether the curve is exponential or sigmoid.

He outlined two possibilities held by colleagues. One, held by some physicist colleagues, is that within a relatively short time AI will be able to answer any question a human mathematician might ask. The profession would then shift from solving problems to asking them. Villani noted that asking the right, relevant questions was always part of research, but it would become the core. The other view is that there will be a phase in which AI solves everything reachable by assembling and developing existing ideas, and only after that would new development become possible again. He tied this to the Navier–Stokes case, where both teams built on a pre-existing idea rather than starting from zero.

31:51

Fewer students, and Villani's own new ones

Anno compared the situation to software, where people, including at Mistral, are saying junior engineers are no longer being hired, and asked whether mathematics jobs will be hit the same way. Villani said nobody knows. He then described a conversation right after the Navier–Stokes announcements with a famous French mathematician, slightly younger than him and an internationally recognized expert in fluid mechanics. She told him she will not take any new PhD students, because she cannot guarantee them a future. She also said she might change fields, because she does not want to use "those crazy tools," and mentioned philosophy as a possibility. Villani stressed that this came from a very senior professor, and that while there is no consensus, some mathematicians are already thinking this way.

His own situation runs the other way, for now. He stopped research for more than a decade, resumed a couple of years ago "by a series of fortunate events," and has results he is proud of. On the day of the interview, he was meeting two new PhD students for the first time. One is doing pure mathematics. The other is in a cooperation with industry and a chemistry professor, and is very expert at using AI. Villani said both are very bright and that he hopes they will find their way.

Still, he expects a tendency to take far fewer students, making the field more elite. That comes on top of an existing shortage. He teaches master's courses at two large universities, in Lyon and Rennes, and his master's classes have between five and ten students, never more. By contrast, he teaches Lebesgue integration to about 100 students at the undergraduate level. He compared the risk to demography: many professors and very few students eventually leads to collapse. He said the whole community feels that 2026 will be remembered as a turning point for mathematics, and that open questions abound. How do prizes work? Who gets to claim one? How do you evaluate a PhD if a student receives a topic, comes back a week later having solved everything, and hands in a 100-page paper?

36:14

Schools, PISA, and the hidden instruction

Villani said things may be even worse in schools than in universities. He cited France's very poor PISA results and described a worldwide collapse in student evaluations, which he called an unprecedented loss in reading, focus, calculation, and logic skills, "very frightening."

He told a story from the previous year. A French secondary-school teacher noticed his students suddenly seemed very good and decided to test them. He emailed them an essay assignment containing a secret instruction written in white text on a white background, telling them to quote Albert Einstein and Maurice Ravel (the second name is unclear in the recording). About two-thirds of the students included both quotations.

To those who say students might still be progressing, Villani replied that it is like doing sports with an exoskeleton: you will not build muscle that way. He said several studies have already found that students who do not use AI end up cleverer than those who do. He compared it to the debate over drugs and creativity, mentioning a claim he attributed to Bill Gates. Perhaps such things can help adults, he said, but with children, who are still building basic skills, one must be very cautious.

38:40

"No AI during the PhD"

Some mathematicians, Villani said, are already telling their students: no AI assistance during the PhD, and afterward they can do what they like. He compared it to a drinking age, "no drinking before 18," after which you are grown up and decide for yourself. His principle: training time requires that you do the training, "not the algorithm."

39:16

The irony of free labor, and André Gorz

Asked what role universities will play when solving or even finding problems may require large sums for tokens, Villani first pointed to what he called an extraordinary irony. Over the past year, many brilliant mathematicians have worked for free, or even paid, to help improve Anthropic's and OpenAI's tools, instead of the companies paying them well for that help.

He connected this to André Gorz, a French philosopher and economist of Marxist inspiration, well known in ecological circles, for a new edition of whose work Villani recently wrote a foreword. Gorz's last book, from the early 2000s, was L'Immatériel (The Immaterial). As Villani described it, the book reflects on how capitalism would find ways to make big money from things with no explicit value in theory, such as culture, ideas, and creativity. The internet came with a promise of freely sharing this personal richness, and Gorz argued capitalism would find ways to rebuild monopolies because it could not tolerate so much value circulating for free. Villani said this is in a way what is happening now. He considers the Marxist habit of asking who is dominant and who is dominated in the economy very appropriate for these times.

41:38

The university as a place for "the ancient art of reasoning"

On the future of university mathematics, Villani offered tentative possibilities, each prefaced with "maybe." The university might become a place to learn to use AI, with basic training in prompting and ethics. Or it might become something like a department of ancient languages, a place to cultivate oneself and "learn the ancient art of reasoning like a human being." Or it might be where a few people cultivate a certain taste, feel, and touch for the things that humans continue to do better.

Villani gave his reasoning about what humans might still contribute. Whenever a result can be evaluated, such as the outcome of a game, the machine eventually beats the biological mind. But he believes the biological mind has two advantages. First, it feels: it has non-logical representations, almost physical, made of emotions and the like. Second, it has a history.

On the first point, he suggested that physically based rather than logic-based intuition might still be better for some problems. These might be the very top-level problems, the most vaguely posed ones, or work aimed at defining a new concept rather than proving a new theorem. Mathematicians like to say you can become famous by finding the right proofs, the right definitions, or the right problems. Perhaps, he said, it will now be more about the definitions and the problems.

On the second point, he used himself as an example. His return to research after a decade away is a particular story, and it matters to people who might want to work with him, in a way that working with an algorithm does not. He compared this to artists who deliberately use old-fashioned cameras because it is part of their narrative.

45:00

Closing exchange

Near the end, Villani brought up widely circulated images of a Japanese figure facing computer programs; the name is unclear in the recording. Anno said he knows the man personally, that the experience was by the man's own account very good for him and made him think, and that he later became president and CEO of the Japanese publisher Kadokawa. As time ran out, Villani promised to send Anno a copy of his book.

The interview ended without a resolution to the questions Villani had raised: whether AI progress in mathematics is exponential or will level off, how authorship and prizes will work, how PhDs can be evaluated, and whether there will still be students. His own answer to most of them was that nobody knows yet.