Existence of Four Minimal Spheres in S^3 with a Bumpy Metric

In 1982, S. T. Yau conjectured that there exists at least four embedded minimal 2-spheres in the 3-sphere with an arbitrary metric. In this talk, we will show that this conjecture holds true for bumpy metrics and metrics with positive Ricci curvature.

This is a joint work with Zhichao Wang (Fudan University).