The Long Slow Road to a $1 Million Millennium Prize
In 2006, the journal Science named the solution to the century-old Poincaré Conjecture as its "breakthrough of the year." Three years later, the Clay Mathematics Institute, which had pledged to award $1 million to the person who solves this or any of six others of its Millennium Prize Problems, has yet to name a winner. The delay sheds light on the onerous process of vetting solutions to mathematics' toughest problems.
