Grigory Perelman, Russian mathematician, was announced to be a recipient of Millennium Prize for his proof of Poincare conjunction.
      
      There are seven Millennium Prize Problems in mathematics, which were stated by Clay Mathematics Institute in 2000. As for today, only one of them was solved – the Poincare conjunction was officially proven by Grigory Perelman in 2003.
      
      The mathematician received Field Prize for his proof, but declined it. The Millennium Prize went to Perelman on March 18, 2010, however, no one still knows whether the scientist would accept the award.
      
      In topology, a sphere with a two-dimensional surface is essentially characterized by the fact that it is simply connected. It is also true that every 2-dimensional surface which is both compact and simply connected is topologically a sphere. The Poincaré conjecture is that this is also true for spheres with three-dimensional surfaces. The question had long been solved for all dimensions above three. Solving it for three is central to the problem of classifying 3-manifolds.
      
      Sources: Science & Technologies
      Wikipedia