Washington Post: A reclusive Russian mathematician, Grigori Perelman, who three months ago was awarded the Clay Mathematics Institute Millennium Prize for proving the Poincaré conjecture, yesterday turned down the award and the $1 million prize. Perelman, who quit his job at the Steklov Institute and lives with his elderly mother in St. Petersburg, has in the past turned down a number of other mathematics awards, including the most prestigious of all, the Fields medal.