MADRID -- A reclusive Russian genius won the Fields Medal, the math world's highest honor, yesterday for work toward resolving a 100-year-old brain-twister about three-dimensional space. But he shunned the ceremony and stayed out of the spotlight.
Grigory Perelman, a 40-year-old native of St. Petersburg, was cited for solving the Poincaré conjecture, a conundrum concerning the nature of three-dimensional space that scientists say might help determine the shape of the universe.
Three other scholars who won Fields Medals, which carry a $13,400 stipend each and are often described as math's equivalent of the Nobel Prize, accepted their prizes from Spain's King Juan Carlos amid rapturous applause at the International Congress of Mathematicians in Madrid.
But Perelman stayed home, said Alexander Abramov, a member of the Russian Education Academy and one of the few people in contact with the scientist .
Serge Rukshin, Perelman's former teacher and scientific supervisor, said Perelman apparently has no interest in medals or money -- only in knowledge.
``Grigory is a devoted scientist in the pure sense of the word. He believes that the most important thing is that the problem is solved," Rukshin said in an interview in St. Petersburg.
Colleagues say Perelman also seems uninterested in a separate $1 million prize he could eventually win for proving the Poincaré conjecture, a theory that has fascinated, and defeated, some of the world's most brilliant minds since it was proposed in 1904.
Perelman could not be reached for comment. Acquaintances said he did not want to talk to the media.
Abramov said in Moscow that he spoke to Perelman by phone and got the impression he may completely give up on math.
``Now I'm most worried about how he feels and what will happen to him. He is a brilliant mathematician. Such talents should not go away," Abramov said.
John Ball, president of the International Mathematical Union, which is holding the convention in Madrid, said Perelman is still considered a Fields medalist.
``I regret that Dr. Perelman has declined to accept the medal," he said.
Ball said later that he met with Perelman in St. Petersburg in June to tell him he had won a Fields Medal and to try to persuade him to accept it. But Perelman said he felt isolated from the mathematics community and would refuse the medal because ``he does not want to be seen as its figurehead," Ball said.
Ball said he asked Perelman whether he would accept the $1 million that goes with the other prize. Perelman said that if he won, he would talk to the Clay Mathematics Institute, a private foundation in Cambridge, Mass., that is offering the prize .
The Fields Medal, which is awarded every four years, was founded in 1936 and named after Canadian mathematician John Charles Fields. This year's three other winners were Andrei Okounkov of Russia, Wendelin Werner of France, and Terence Tao, an Australian.
In 2000, the Clay Mathematics Institute announced bounties for seven historic, unsolved math problems, including the Poincaré conjecture. If his proof stands the test of time, Perelman will win all or part of the $1 million prize money. That prize should be announced in about two years. Until then, academics can challenge Perelman's work.
That work draws heavily from a technique developed by another mathematician, Richard Hamilton of Columbia University. The Clay Mathematics Institute says the two men could conceivably share the Poincaré money.
The Poincaré conjecture is key to the field of topology, which studies shapes. It basically says that in three dimensions a doughnut shape cannot be transformed into a sphere without ripping it, although any shape without a hole can be stretched or shrunk into a sphere.
Perelman spent eight years wrestling with the problem. He left the first of three short papers with what he called proof on an Internet archive in November 2002, and gave a lecture tour on it at top American universities. He returned to Russia and all but vanished, sitting back to let the math world sink its teeth into his work.
Since then, mathematicians have been scrutinizing the proof papers. The review continues -- but no one has found a serious flaw, the International Mathematical Union said.