Perelman 2003
Perelman 2003
Every simply connected, closed 3-manifold is homeomorphic to the 3-sphere. Settled by Perelman (2002–03) via Ricci flow with surgery, entropy monotonicity, and no collapsing.
Poincaré —opens→ Perelman 2003
Entropy functional —implies→ Perelman 2003
Surgery —implies→ Perelman 2003
Ricci flow —implies→ Perelman 2003