# The Clay Mathematics Institute

The call for nominations for 2017 Clay Research Fellowships is open. Research Fellows are selected for their research achievements and their potential to become leaders in research mathematics. All are recent PhDs, and most are selected as they complete their thesis work. The fellowships provide generous salary and research expenses, and can be held at any university in the world.

Closing date for nominations: November 16

## Millennium Problems

In 1904 the French mathematician Henri Poincaré asked if the three dimensional sphere is characterized as the unique simply connected three manifold. This question, the Poincaré conjecture, was a special case of Thurston's geometrization conjecture. Perelman's proof tells us that every three manifold is built from a set of standard pieces, each with one of eight well-understood geometries.