Imagine solving one of the hardest puzzles in the history of mathematics, and then simply turning around and going back to ordinary life. No interviews, no prizes, no publicity. This is the story of Grigori Perelman, the Russian mathematician who proved the Poincaré conjecture and turned down a million dollars.
Who is Grigori Perelman?
Grigori Perelman was born in 1966 in Leningrad (today Saint Petersburg). Even as a teenager he showed remarkable talent: in 1982 he won a gold medal at the International Mathematical Olympiad with a perfect score. He later worked at the Steklov Institute, focusing on geometry and topology.
His greatest achievement came in the early 2000s. In 2002 and 2003 he published a series of preprints on ArXiv in which he proved the Poincaré conjecture, a problem formulated in 1904 by Henri Poincaré.
What exactly did Perelman solve?
The Poincaré conjecture concerned three-dimensional shapes (three-dimensional manifolds). Put simply, it said that if a space is “simple” like a sphere (every loop in it can be shrunk to a point), then it is topologically a sphere. Sounds abstract? Imagine a balloon: you can squash it in many ways, but its basic “shapeness” stays the same. Perelman showed how this works in three dimensions.
His proof was built on Richard Hamilton’s theory of Ricci flow. It works like sending a “wave of heat” through a shape, smoothing it out and helping us understand its structure. Perelman added the key elements that made it possible to solve the problem.
His work was so groundbreaking that it also proved the broader Thurston geometrization conjecture.
Why did he refuse a million dollars?
In 2010 the Clay Mathematics Institute awarded him the Millennium Prize, a million dollars for solving one of the seven hardest problems in mathematics. Perelman simply… refused. He did not appear at the ceremony in Paris.
He said his contribution was no greater than Hamilton’s, and that the committee’s decision was unfair. He did not want to take part in a “system” that, in his view, rewards spectacle rather than pure science. Earlier he had also turned down the Fields Medal, the mathematical equivalent of the Nobel Prize.
It was not poverty or eccentricity for show. Perelman simply valued mathematics for its own sake. “I have everything I need,” he reportedly said.
Life away from the spotlight
Today Perelman leads a very quiet life in Saint Petersburg. He looks after his mother, avoids the media and has not given interviews for many years. From time to time there are reports that he is interested in other problems, such as the Navier-Stokes equations.
