Obtaining PhD from Rutgers University, his research concentrates on geometric topology. He studies low dimensional topology, including knot theory, 3- and 4-dimensional topology, with a special attention to exotic smooth structures on 4-manifolds. He also works on symplectic and contact topology. Gauge theoretic invariants (such as Seiberg-Witten and Heegaard Floer invariants) play crucial roles in these studies.